Vertebral Artery Insufficiency

Complex MONDO:0001631 Pathograph 27 Show in embeddings browser Vascular insufficiency disorder Arterial disorder Transient ischemic attack

Vertebral artery insufficiency is a posterior-circulation vascular disorder in which vertebral or vertebrobasilar stenosis, occlusion, dissection, injury, hypoplasia with superimposed stenosis or limited collateral reserve, or extrinsic bony compression compromises perfusion or generates embolic ischemia in the brainstem, cerebellar, thalamic, or occipital circulation. Clinical presentations overlap with vertebrobasilar insufficiency, symptomatic vertebrobasilar disease, posterior-circulation transient ischemic attack, and posterior-circulation ischemic stroke.

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11
Pathophys.
10
Phenotypes
27
Pathograph
5
Medical Actions
2
Trials
14
References
1
Deep Research
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Pathophysiology

11
Atherosclerotic vertebral artery stenosis
Atherosclerotic narrowing of extracranial or intracranial vertebral arteries is a major substrate for symptomatic vertebrobasilar disease. Percentage stenosis alone does not predict vertebral flow loss; severe bilateral or tandem disease, a small residual lumen, contralateral occlusion or hypoplasia, and limited collateral reserve can create hemodynamic compromise.
endothelial cell CL:0000115 Cell Ontology (CL) Relation: this pathophysiological event involves this cell type This pathophysiological event involves endothelial cell (CL:0000115). CL:0000115 is a cell type from the Cell Ontology. vascular smooth muscle cell CL:0000192 Cell Ontology (CL) Relation: this pathophysiological event involves this cell type This pathophysiological event involves vascular smooth muscle cell, annotated with smooth muscle cell (CL:0000192). CL:0000192 is a cell type from the Cell Ontology.
vertebral artery UBERON:0001535 Uberon multi-species anatomy ontology (UBERON) Relation: this pathophysiological event occurs in this anatomical location This pathophysiological event occurs in vertebral artery (UBERON:0001535). UBERON:0001535 is an anatomical location from the Uberon multi-species anatomy ontology.
Downstream
Posterior circulation hypoperfusion Severe vertebral stenosis can contribute to distal hypoperfusion when residual lumen and compensatory inflow or collateral capacity are inadequate.
Vertebrobasilar thromboembolism Atherosclerotic stenosis can produce a low-flow state that promotes local thrombus formation.
Show evidence (3 references)
PMID:21050408 SUPPORT Human Clinical
"Over one-third of ischaemic strokes occur in the posterior circulation, and a leading cause is atherosclerotic vertebrobasilar disease."
This identifies atherosclerotic disease encompassing vertebral lesions as a leading posterior-circulation ischemic stroke cause.
PMID:25977279 SUPPORT Human Clinical
"Patients with recent vertebrobasilar transient ischemic attack or stroke and ≥50% atherosclerotic stenosis or occlusion in vertebral or basilar arteries (BA) were enrolled."
The VERiTAS cohort explicitly included symptomatic atherosclerotic vertebral stenosis.
PMID:25977279 SUPPORT Human Clinical
"The correlation between flow and the residual diameter at the site of stenosis was more robust and evident both in the BA (rho=0.65, p<0.01 for BA) and VA (rho=0.62, p<0.01) (Figure 1)."
Residual vertebral lumen, rather than percentage stenosis alone, is associated with local vertebral flow; this only partially supports the broader disease node.
Atherosclerotic vertebral artery occlusion
Atherosclerotic vertebral artery occlusion is modeled separately from stenosis so interventions supported only for stenotic lesions do not export to chronic total occlusion. Occlusion can cause posterior-circulation ischemia, while its hemodynamic impact depends on the opposite vertebral artery and collateral circulation.
vertebral artery UBERON:0001535 Uberon multi-species anatomy ontology (UBERON) Relation: this pathophysiological event occurs in this anatomical location This pathophysiological event occurs in vertebral artery (UBERON:0001535). UBERON:0001535 is an anatomical location from the Uberon multi-species anatomy ontology.
Downstream
Posterior circulation ischemia Vertebral artery occlusion can cause medullary or cerebellar ischemia and transient ischemic attacks.
Show evidence (2 references)
PMID:25977279 SUPPORT Human Clinical
"Patients with recent vertebrobasilar transient ischemic attack or stroke and ≥50% atherosclerotic stenosis or occlusion in vertebral or basilar arteries (BA) were enrolled."
The adjudicated atherosclerotic cohort included symptomatic vertebral artery occlusion.
PMID:35301953 SUPPORT Human Clinical
"Occlusion of the extracranial V.A. causes ischemia in the medulla and/or cerebellum and usually manifests as brief TIAs."
Establishes the posterior-circulation ischemic consequence of extracranial vertebral occlusion.
Atherosclerotic basilar artery stenosis or occlusion
Atherosclerotic narrowing or occlusion of the basilar artery is a distinct vertebrobasilar lesion that can reduce basilar and distal posterior-circulation flow. It is modeled separately so vertebral-artery interventions are not generalized to basilar disease.
endothelial cell CL:0000115 Cell Ontology (CL) Relation: this pathophysiological event involves this cell type This pathophysiological event involves endothelial cell (CL:0000115). CL:0000115 is a cell type from the Cell Ontology. vascular smooth muscle cell CL:0000192 Cell Ontology (CL) Relation: this pathophysiological event involves this cell type This pathophysiological event involves vascular smooth muscle cell, annotated with smooth muscle cell (CL:0000192). CL:0000192 is a cell type from the Cell Ontology.
basilar artery UBERON:0001633 Uberon multi-species anatomy ontology (UBERON) Relation: this pathophysiological event occurs in this anatomical location This pathophysiological event occurs in basilar artery (UBERON:0001633). UBERON:0001633 is an anatomical location from the Uberon multi-species anatomy ontology.
Downstream
Posterior circulation hypoperfusion Severe basilar artery stenosis or occlusion can reduce distal posterior-circulation flow.
Show evidence (2 references)
PMID:25977279 SUPPORT Human Clinical
"Patients with recent vertebrobasilar transient ischemic attack or stroke and ≥50% atherosclerotic stenosis or occlusion in vertebral or basilar arteries (BA) were enrolled."
The VERiTAS cohort explicitly included symptomatic atherosclerotic basilar stenosis or occlusion.
PMID:25977279 SUPPORT Human Clinical
"For the BA, the largest and most statistically significant drop in vessel flow was first encountered at a threshold of 80% stenosis (p=0.02)"
Quantifies basilar-artery flow loss at severe stenosis.
Posterior circulation hypoperfusion
Low vertebrobasilar flow can impair perfusion reserve in posterior circulation territories. Quantitative magnetic resonance angiography (QMRA) is used in VERiTAS-style assessments to distinguish low from normal distal flow and to evaluate risk beyond anatomic stenosis alone.
brainstem UBERON:0002298 Uberon multi-species anatomy ontology (UBERON) Relation: this pathophysiological event occurs in this anatomical location This pathophysiological event occurs in brainstem (UBERON:0002298). UBERON:0002298 is an anatomical location from the Uberon multi-species anatomy ontology. cerebellum UBERON:0002037 Uberon multi-species anatomy ontology (UBERON) Relation: this pathophysiological event occurs in this anatomical location This pathophysiological event occurs in cerebellum (UBERON:0002037). UBERON:0002037 is an anatomical location from the Uberon multi-species anatomy ontology. occipital lobe UBERON:0002021 Uberon multi-species anatomy ontology (UBERON) Relation: this pathophysiological event occurs in this anatomical location This pathophysiological event occurs in occipital lobe (UBERON:0002021). UBERON:0002021 is an anatomical location from the Uberon multi-species anatomy ontology.
Downstream
Posterior circulation ischemia Sustained or recurrent low flow can culminate in posterior-circulation TIA or infarction.
Show evidence (2 references)
PMID:21050408 SUPPORT Human Clinical
"Preliminary studies indicate that stroke risk in vertebrobasilar disease is strongly related to haemodynamic compromise, which can be measured noninvasively using quantitative magnetic resonance angiography."
This supports hemodynamic compromise as an upstream risk mechanism measurable with QMRA.
PMID:25977279 SUPPORT Human Clinical
"Flow in stenotic posterior circulation vessels correlates with residual diameter and drops significantly with tandem disease."
This directly supports reduced flow downstream of posterior-circulation stenotic disease.
Vertebrobasilar thromboembolism
Vertebrobasilar atherostenosis can produce ischemia by thromboembolism as well as by flow failure. Hypoperfusion may also reduce embolus washout and promote local thrombus formation at diseased arterial segments.
endothelial cell CL:0000115 Cell Ontology (CL) Relation: this pathophysiological event involves this cell type This pathophysiological event involves endothelial cell (CL:0000115). CL:0000115 is a cell type from the Cell Ontology. platelet CL:0000233 Cell Ontology (CL) Relation: this pathophysiological event involves this cell type This pathophysiological event involves platelet (CL:0000233). CL:0000233 is a cell type from the Cell Ontology.
blood coagulation GO:0007596 Gene Ontology (GO) Relation: this pathophysiological event involves this biological process This pathophysiological event involves increased blood coagulation (GO:0007596). GO:0007596 is a biological process from the Gene Ontology. ↑ INCREASED
Downstream
Posterior circulation ischemia Emboli or local thrombosis can occlude posterior-circulation branches and cause transient or completed ischemia.
Show evidence (1 reference)
PMID:21050408 SUPPORT Human Clinical
"Furthermore, both embolic and flow processes can synergize to increase stroke risk; a proposed mechanism is the reduced wash-out of emboli from the distal circulation in hypoperfused regions (6, 7). Low flow may also promote local thrombus formation at the site of disease, with resultant stroke (3)."
This supports mixed embolic and flow-mediated mechanisms linking vertebrobasilar disease to stroke.
Vertebral artery dissection
Vertebral artery dissection begins with a wall tear and mural blood entry and can compromise the lumen through stenosis, occlusion, or thrombosis. It is modeled separately from other traumatic vertebral injuries because the headache and neck-pain evidence is specific to dissection.
vertebral artery UBERON:0001535 Uberon multi-species anatomy ontology (UBERON) Relation: this pathophysiological event occurs in this anatomical location This pathophysiological event occurs in vertebral artery (UBERON:0001535). UBERON:0001535 is an anatomical location from the Uberon multi-species anatomy ontology.
Downstream
Posterior circulation ischemia Vertebral artery dissection can cause posterior-circulation TIA or stroke through thrombosis or stenosis-driven hypoperfusion.
Headache Vertebral artery dissection can directly present with headache.
Neck pain Vertebral artery dissection can directly present with neck pain.
Show evidence (1 reference)
DOI:10.1186/s41983-024-00893-x SUPPORT Human Clinical
"Vertebral artery dissection occurs due to a tear in the vertebral artery wall, which results in blood flow entering the blood vessel wall."
This supports mural dissection as a vertebral artery mechanism that can lead to insufficiency or ischemia.
Traumatic vertebral artery injury
Blunt or penetrating cervical trauma can injure the vertebral artery and is associated with posterior-circulation stroke. The available meta-analysis quantifies that outcome but does not establish a direct transition, so vascular luminal compromise and thromboembolism remain known omitted intermediates.
vertebral artery UBERON:0001535 Uberon multi-species anatomy ontology (UBERON) Relation: this pathophysiological event occurs in this anatomical location This pathophysiological event occurs in vertebral artery (UBERON:0001535). UBERON:0001535 is an anatomical location from the Uberon multi-species anatomy ontology.
Downstream
Posterior circulation ischemia Traumatic vertebral artery injury is associated with posterior stroke through omitted vascular-lesion and thromboembolic mechanisms.
Show evidence (1 reference)
PMID:37924280 SUPPORT Human Clinical
"VAI in cervical spine trauma has an approximate posterior circulation stroke risk of 9%."
This meta-analysis quantifies posterior-circulation stroke risk after traumatic vertebral artery injury.
Extrinsic bony compression of the vertebral artery
Mechanical compression of the vertebral artery by adjacent bone is a non-atherosclerotic, structural route to vertebral artery stenosis. Because the vessel traverses the cervical transverse foramina, osteophytes and other bony encroachment can narrow the lumen. The cited review establishes bony compression as one of several non-atherosclerotic stenosis etiologies; it does not characterize position-dependent or rotational compression, so no dynamic-compression claim is asserted here.
vertebral artery UBERON:0001535 Uberon multi-species anatomy ontology (UBERON) Relation: this pathophysiological event occurs in this anatomical location This pathophysiological event occurs in vertebral artery (UBERON:0001535). UBERON:0001535 is an anatomical location from the Uberon multi-species anatomy ontology.
Downstream
Posterior circulation hypoperfusion Bony encroachment can cause vertebral stenosis, which is the known omitted intermediate through which distal posterior-circulation flow may fall.
Show evidence (2 references)
PMID:36127977 SUPPORT Human Clinical
"Mechanical compression of the vertebral artery by bone can also cause stenosis of the vertebral artery."
This review establishes bony compression as a distinct, non-atherosclerotic cause of vertebral artery stenosis.
PMID:36127977 SUPPORT Human Clinical
"There are several causes of vertebral artery stenosis, including atherosclerosis, calcification, dissections, fibromuscular dysplasia, giant cell arteritis, neurofibromatosis type 1, and bony compressions."
This enumerates bony compression alongside atherosclerosis and dissection as a recognized stenosis etiology, supporting it as a separate mechanism node.
Vertebral artery hypoplasia
Congenital hypoplasia produces a smaller-caliber vertebral artery. It is not itself sufficient to cause vertebrobasilar insufficiency, but a superimposed stenosis leaves a smaller residual lumen in a hypoplastic artery than the same percentage stenosis in a dominant artery.
vertebral artery UBERON:0001535 Uberon multi-species anatomy ontology (UBERON) Relation: this pathophysiological event occurs in this anatomical location This pathophysiological event occurs in vertebral artery (UBERON:0001535). UBERON:0001535 is an anatomical location from the Uberon multi-species anatomy ontology.
Downstream
Posterior circulation hypoperfusion With superimposed stenosis, a hypoplastic vertebral artery has a smaller residual lumen; stenosis and residual-lumen restriction are known intermediates between the congenital caliber variant and distal flow loss.
Show evidence (3 references)
PMID:12870261 SUPPORT Human Clinical
"Angiography revealed hypoplasia of left vertebral artery (VA) and remarkable stenosis of the proximal right VA with inadequate collateral flow from the anterior circulation."
This documents contralateral hypoplasia plus inadequate anterior-circulation collateral flow as the anatomical context in which unilateral stenosis became symptomatic; case-level evidence only.
PMID:40951011 SUPPORT Human Clinical
"CTA revealed severe stenosis of the left vertebral artery V4 segment, with a hypoplastic right vertebral artery."
A second case pairing a hypoplastic contralateral vertebral artery with symptomatic stenosis, supporting reduced collateral reserve as a modifying substrate; case-level evidence only.
PMID:25977279 SUPPORT Human Clinical
"the same % stenosis leads to a markedly smaller residual diameter in a hypoplastic 2 mm vertebral compared to a dominant 5 mm VA"
Directly distinguishes the smaller residual lumen produced when stenosis affects a hypoplastic rather than dominant vertebral artery.
Limited posterior-circulation collateral capacity
Limited compensatory supply through contralateral vertebral and posterior-circulation collateral pathways can leave distal flow low despite similar local stenosis severity. This regional hemodynamic state is distinct from vertebral artery hypoplasia and from the local stenotic lesion.
vertebral artery UBERON:0001535 Uberon multi-species anatomy ontology (UBERON) Relation: this pathophysiological event occurs in this anatomical location This pathophysiological event occurs in vertebral artery (UBERON:0001535). UBERON:0001535 is an anatomical location from the Uberon multi-species anatomy ontology. basilar artery UBERON:0001633 Uberon multi-species anatomy ontology (UBERON) Relation: this pathophysiological event occurs in this anatomical location This pathophysiological event occurs in basilar artery (UBERON:0001633). UBERON:0001633 is an anatomical location from the Uberon multi-species anatomy ontology.
Downstream
Posterior circulation hypoperfusion Inadequate collateral contribution is a determinant of low regional distal flow.
Show evidence (2 references)
PMID:12870261 SUPPORT Human Clinical
"Angiography revealed hypoplasia of left vertebral artery (VA) and remarkable stenosis of the proximal right VA with inadequate collateral flow from the anterior circulation."
Case-level evidence documents inadequate anterior-circulation collateral flow separately from the vertebral lesions.
PMID:25977279 SUPPORT Human Clinical
"hemodynamic assessment of the distal flow status in the posterior circulation, which incorporates the contribution of any large vessel collateral flow, is not well predicted by either the severity or location of the disease"
Establishes collateral-integrated distal flow as a regional hemodynamic property distinct from local stenosis severity and location.
Posterior circulation ischemia
Final common ischemic injury occurs when hemodynamic compromise or thromboembolism reduces oxygen delivery to brainstem, cerebellar, thalamic, or occipital territories, causing transient ischemic attacks, ischemic stroke, or recurrent posterior-circulation symptoms.
brainstem UBERON:0002298 Uberon multi-species anatomy ontology (UBERON) Relation: this pathophysiological event occurs in this anatomical location This pathophysiological event occurs in brainstem (UBERON:0002298). UBERON:0002298 is an anatomical location from the Uberon multi-species anatomy ontology. cerebellum UBERON:0002037 Uberon multi-species anatomy ontology (UBERON) Relation: this pathophysiological event occurs in this anatomical location This pathophysiological event occurs in cerebellum (UBERON:0002037). UBERON:0002037 is an anatomical location from the Uberon multi-species anatomy ontology. occipital lobe UBERON:0002021 Uberon multi-species anatomy ontology (UBERON) Relation: this pathophysiological event occurs in this anatomical location This pathophysiological event occurs in occipital lobe (UBERON:0002021). UBERON:0002021 is an anatomical location from the Uberon multi-species anatomy ontology.
Downstream
Vertigo Posterior-circulation ischemia can manifest clinically as vertigo.
Transient ischemic attack Transient posterior-circulation ischemia manifests as vertebrobasilar TIA.
Ataxia Cerebellar or brainstem ischemia can manifest as ataxia.
Diplopia Posterior-circulation ischemia involving ocular motor pathways can manifest as diplopia.
Dysarthria Posterior-circulation neurologic dysfunction can manifest as dysarthria.
Dysphagia Brainstem or lower cranial nerve dysfunction from posterior-circulation ischemia can manifest as dysphagia.
Ischemic stroke Persistent posterior-circulation ischemia can culminate in ischemic stroke.
Show evidence (1 reference)
PMID:35301953 SUPPORT Human Clinical
"Patients with posterior circulation ischemia due to vertebral artery stenosis account for 20 to 25% of ischemic strokes and have an increased risk of recurrent stroke."
This directly links vertebral artery stenosis to posterior-circulation ischemia and ischemic stroke burden.
⬡

Pathograph

Use the checkboxes to hide or show graph categories. Hover nodes for evidence and cross-linked metadata.
Pathograph: causal mechanism network for Vertebral Artery Insufficiency Interactive directed graph showing how pathophysiology mechanisms, phenotypes, genetic factors and variants, experimental models, environmental triggers, and treatments relate through causal and linked edges.
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Phenotypes

10
Cardiovascular 1
Ischemic stroke HP:0002140 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is ischemic stroke (HP:0002140). HP:0002140 is a phenotype from the Human Phenotype Ontology.
Show evidence (2 references)
PMID:35301953 SUPPORT Human Clinical
"Patients with posterior circulation ischemia due to vertebral artery stenosis account for 20 to 25% of ischemic strokes and have an increased risk of recurrent stroke."
This directly links vertebral artery stenosis-related posterior circulation ischemia to ischemic stroke burden.
PMID:37924280 SUPPORT Human Clinical
"From the 16 studies which reported data on outcomes, 8.87% (95% CI 5.34- 12.99) of patients with VAI had a posterior stroke."
This meta-analysis supports posterior stroke as an outcome in trauma-associated vertebral artery injury.
Digestive 1
Dysphagia HP:0002015 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is dysphagia (HP:0002015). HP:0002015 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:12870261 SUPPORT Human Clinical
"A 69-year-old man was admitted because of dysarthria and dysphagia. Angiography revealed hypoplasia of left vertebral artery (VA) and remarkable stenosis of the proximal right VA with inadequate collateral flow from the anterior circulation."
This vertebral artery origin stenosis case supports dysphagia as a posterior-circulation symptom, but the evidence is case-level.
Ear 1
Vertigo HP:0002321 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is vertigo (HP:0002321), qualified as temporality recurrent. HP:0002321 is a phenotype from the Human Phenotype Ontology.
Temporal: RECURRENT
Show evidence (2 references)
PMID:40148099 SUPPORT Human Clinical
"Vertigo was the most common reported symptom, within a total of 37 different symptoms reported either in isolation or combination."
This systematic review supports vertigo as the most common reported symptom in atherosclerotic VBI cases.
PMID:40951011 SUPPORT Human Clinical
"This case emphasizes that recurrent atypical vertigo and brief syncope may be warning signs of vertebrobasilar insufficiency, especially in the context of vertebral artery stenosis with limited collateral flow."
This case report supports recurrent vertigo as a warning symptom in a vertebral stenosis and hypoplastic collateral-flow presentation, but case-level evidence is indirect for population frequency.
Eye 1
Diplopia HP:0000651 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is diplopia (HP:0000651). HP:0000651 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:28680502 SUPPORT Human Clinical
"Dizziness, vertigo, headaches, vomit, diplopia, blindness, ataxia, imbalance, and weakness in both sides of the body are the most common symptoms."
This review identifies diplopia as a common symptom of vertebrobasilar insufficiency.
Nervous System 3
Ataxia HP:0001251 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is ataxia (HP:0001251). HP:0001251 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:28680502 SUPPORT Human Clinical
"Dizziness, vertigo, headaches, vomit, diplopia, blindness, ataxia, imbalance, and weakness in both sides of the body are the most common symptoms."
This review identifies ataxia as a common symptom of vertebrobasilar insufficiency.
Dysarthria HP:0001260 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is dysarthria (HP:0001260). HP:0001260 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:12870261 SUPPORT Human Clinical
"A 69-year-old man was admitted because of dysarthria and dysphagia. Angiography revealed hypoplasia of left vertebral artery (VA) and remarkable stenosis of the proximal right VA with inadequate collateral flow from the anterior circulation."
This vertebral artery origin stenosis case supports dysarthria as a posterior-circulation symptom, but the evidence is case-level.
Headache HP:0002315 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is headache (HP:0002315). HP:0002315 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
DOI:10.1186/s41983-024-00893-x SUPPORT Human Clinical
"The most frequent clinical manifestations include stroke, transient ischemic attack, neck pain, headaches, and vertigo."
This review supports headache as a frequent manifestation in vertebral artery dissection.
Other 3
Abnormal vertebral artery morphology HP:0030321 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is abnormal vertebral artery morphology (HP:0030321). HP:0030321 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:12870261 SUPPORT Human Clinical
"Angiography revealed hypoplasia of left vertebral artery (VA) and remarkable stenosis of the proximal right VA with inadequate collateral flow from the anterior circulation."
Case-level angiography directly documents hypoplasia and stenosis of the vertebral arteries; basilar lesions and collateral flow are not classified as vertebral morphology here.
Transient ischemic attack HP:0002326 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is transient ischemic attack (HP:0002326), qualified as temporality transient. HP:0002326 is a phenotype from the Human Phenotype Ontology.
Temporal: TRANSIENT
Show evidence (2 references)
PMID:25977279 SUPPORT Human Clinical
"METHODS: Patients with recent vertebrobasilar transient ischemic attack or stroke and ≥50% atherosclerotic stenosis or occlusion in vertebral or basilar arteries (BA) were enrolled."
This directly identifies recent vertebrobasilar TIA as a qualifying clinical presentation in symptomatic vertebrobasilar stenosis or occlusion.
DOI:10.1186/s41983-024-00893-x SUPPORT Human Clinical
"The most frequent clinical manifestations include stroke, transient ischemic attack, neck pain, headaches, and vertigo."
This supports TIA among common manifestations in dissection-associated vertebral artery disease.
Neck pain HP:0030833 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is neck pain (HP:0030833). HP:0030833 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
DOI:10.1186/s41983-024-00893-x SUPPORT Human Clinical
"The most frequent clinical manifestations include stroke, transient ischemic attack, neck pain, headaches, and vertigo."
This review supports neck pain as a frequent manifestation in vertebral artery dissection.
💊

Medical Actions

5
Aggressive medical secondary prevention
Action: PharmacotherapyNCI Thesaurus (NCIT) Relation: this treatment is this clinical intervention This treatment is Pharmacotherapy (NCIT:C15986). NCIT:C15986 is a clinical intervention from the NCI Thesaurus. NCIT:C15986
Agent: aspirin CHEBI:15365 Chemical Entities of Biological Interest (CHEBI) Relation: this treatment uses this therapeutic agent This treatment uses aspirin, annotated with acetylsalicylic acid (CHEBI:15365). CHEBI:15365 is a therapeutic agent from Chemical Entities of Biological Interest. statin CHEBI:87631 Chemical Entities of Biological Interest (CHEBI) Relation: this treatment uses this therapeutic agent This treatment uses statin (CHEBI:87631). CHEBI:87631 is a therapeutic agent from Chemical Entities of Biological Interest.
Standard medical management focuses on antithrombotic therapy, statins, and intensive cerebrovascular risk-factor control. For high-risk minor posterior circulation stroke or TIA, short-term dual antiplatelet therapy may be used before transition to monotherapy.
Target Phenotypes: transient ischemic attack HP:0002326 Human Phenotype Ontology (HP) Relation: this treatment targets this phenotype This treatment targets transient ischemic attack (HP:0002326). HP:0002326 is a phenotype from the Human Phenotype Ontology. ischemic stroke HP:0002140 Human Phenotype Ontology (HP) Relation: this treatment targets this phenotype This treatment targets ischemic stroke (HP:0002140). HP:0002140 is a phenotype from the Human Phenotype Ontology.
Show evidence (2 references)
PMID:21050408 SUPPORT Human Clinical
"The patients are prospectively followed for a minimum of one year on current standard medical regimen including vascular risk factor modification, statins and antithrombotic therapy, and evaluated for recurrent ischemic events."
This supports vascular risk-factor modification, statins, and antithrombotic therapy as standard medical management in symptomatic vertebrobasilar disease.
PMID:35658624 SUPPORT Human Clinical
"Secondary prevention of posterior circulation strokes includes aggressive treatment of cerebrovascular risk factors with both drugs and lifestyle interventions and short-term dual anti-platelet therapy."
This supports aggressive medical secondary prevention and short-term dual antiplatelet therapy for posterior-circulation stroke contexts.
Vertebral artery angioplasty and stenting
Action: placement of a stentNCI Thesaurus (NCIT) Relation: this treatment is this clinical intervention This treatment is placement of a stent, annotated with Stenting (NCIT:C71316). NCIT:C71316 is a clinical intervention from the NCI Thesaurus. Ontology label: Stenting NCIT:C71316
Endovascular angioplasty and stenting can restore vertebral artery patency in selected symptomatic extracranial vertebral stenosis, especially with recurrent symptoms despite medical therapy, but trial evidence has not conclusively shown superiority over medical therapy and intracranial stenting carries higher procedural risk.
Mechanism Target:
RESTORES Atherosclerotic vertebral artery stenosis — Stenting attempts to restore arterial lumen and improve flow across stenotic vertebral artery segments.
Show evidence (1 reference)
PMID:35301953 SUPPORT Human Clinical
"Percutaneous transluminal angioplasty and stenting of symptomatic vertebral artery stenosis are promising options widely used in clinical practice with good technical results; however, the improved clinical outcome has been examined in various clinical trials without a sufficient sample size to..."
Supports the intervention acting on the stenosis node with good technical result, while preserving the unresolved outcome question.
Show evidence (2 references)
PMID:35301953 SUPPORT Human Clinical
"Percutaneous transluminal angioplasty and stenting of symptomatic vertebral artery stenosis are promising options widely used in clinical practice with good technical results; however, the improved clinical outcome has been examined in various clinical trials without a sufficient sample size to..."
This supports clinical use of angioplasty/stenting but preserves uncertainty about outcome superiority over medical therapy.
PMID:40951011 SUPPORT Human Clinical
"Given refractory symptoms despite dual antiplatelet therapy and permissive hypertension, urgent intracranial balloon angioplasty and balloon-mounted drug-eluting stent placement was performed."
This case report supports stenting as an intervention for refractory vertebrobasilar insufficiency from vertebral artery stenosis, but evidence remains case-level.
Microsurgical vertebral artery revascularization
Action: surgical procedure on vascular systemNCI Thesaurus (NCIT) Relation: this treatment is this clinical intervention This treatment is surgical procedure on vascular system, annotated with Vascular Surgical Procedure (NCIT:C157725). NCIT:C157725 is a clinical intervention from the NCI Thesaurus. Ontology label: Vascular Surgical Procedure NCIT:C157725
Vertebral endarterectomy, artery transposition, hybrid surgery, or related microsurgical reconstruction may be considered for selected proximal vertebral artery stenosis or occlusion when endovascular treatment is unsuitable, fails, or restenosis occurs.
Mechanism Target:
RESTORES Atherosclerotic vertebral artery stenosis — Microsurgical reconstruction attempts to restore vertebral artery inflow or bypass obstructive anatomy.
Show evidence (2 references)
PMID:39673653 SUPPORT Human Clinical
"Postoperative imaging examinations in the 34 patients (Males: 79.4%; Mean age: 66.7 ± 9.6 years) revealed patent vertebral and supplying arteries."
Post-operative vessel patency is the direct imaging readout that this link's restored-inflow claim asserts.
PMID:37483445 SUPPORT Human Clinical
"Microsurgical reconstruction is an alternative option that can effectively treat refractory proximal VASO disease and in-stent stenosis, with a high rate of postoperative vascular recirculation."
Restored vascular recirculation is the mechanism by which this intervention acts on vertebral stenosis.
RESTORES Atherosclerotic vertebral artery occlusion — Selected microsurgical reconstructions can restore vertebral inflow or bypass proximal occlusive anatomy.
Show evidence (1 reference)
PMID:37483445 SUPPORT Human Clinical
"Microsurgical reconstruction is an alternative option that can effectively treat refractory proximal VASO disease and in-stent stenosis, with a high rate of postoperative vascular recirculation."
The VASO cohort includes proximal vertebral occlusive disease and reports restoration of vascular recirculation after reconstruction.
Show evidence (2 references)
PMID:37483445 SUPPORT Human Clinical
"Microsurgical reconstruction is an alternative option that can effectively treat refractory proximal VASO disease and in-stent stenosis, with a high rate of postoperative vascular recirculation."
This supports microsurgical reconstruction for refractory proximal vertebral artery stenosis/occlusion and in-stent stenosis.
PMID:39673653 SUPPORT Human Clinical
"Microsurgical surgery for patients with proximal vertebral artery stenosis, when endovascular treatment is unsuitable, demonstrates good clinical efficacy and a low incidence of complications, offering a viable surgical treatment option."
This supports microsurgical surgery in selected proximal vertebral stenosis patients unsuitable for endovascular treatment.
Acute posterior circulation thrombolysis
Action: PharmacotherapyNCI Thesaurus (NCIT) Relation: this treatment is this clinical intervention This treatment is Pharmacotherapy (NCIT:C15986). NCIT:C15986 is a clinical intervention from the NCI Thesaurus. NCIT:C15986
When vertebral artery insufficiency progresses to posterior-circulation ischemic stroke, intravenous thrombolysis may be considered according to acute stroke eligibility.
Target Phenotypes: ischemic stroke HP:0002140 Human Phenotype Ontology (HP) Relation: this treatment targets this phenotype This treatment targets ischemic stroke (HP:0002140). HP:0002140 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:35658624 SUPPORT Human Clinical
"Thrombolysis seems to have similar benefits and lower hemorrhage risks than in the anterior circulation. The recent ATTENTION and BAOCHE trials have demonstrated that thrombectomy benefits strokes with basilar artery occlusion, but its effect on other posterior occlusion sites remains uncertain."
This supports thrombolysis as an acute reperfusion treatment for posterior-circulation stroke.
Basilar artery mechanical thrombectomy
Action: thrombectomyNCI Thesaurus (NCIT) Relation: this treatment is this clinical intervention This treatment is thrombectomy (NCIT:C52003). NCIT:C52003 is a clinical intervention from the NCI Thesaurus. Ontology label: Thrombectomy NCIT:C52003
Mechanical thrombectomy is relevant when posterior-circulation ischemic stroke involves basilar artery occlusion, while evidence for other posterior occlusion sites remains less certain.
Target Phenotypes: ischemic stroke HP:0002140 Human Phenotype Ontology (HP) Relation: this treatment targets this phenotype This treatment targets ischemic stroke (HP:0002140). HP:0002140 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:35658624 SUPPORT Human Clinical
"Thrombolysis seems to have similar benefits and lower hemorrhage risks than in the anterior circulation. The recent ATTENTION and BAOCHE trials have demonstrated that thrombectomy benefits strokes with basilar artery occlusion, but its effect on other posterior occlusion sites remains uncertain."
This supports thrombectomy for basilar artery occlusion while preserving uncertainty for other posterior-circulation occlusion sites.
🌍

Environmental Factors

2
Atherosclerotic vascular risk factor burden
Symptomatic vertebrobasilar disease cohorts have a high prevalence of conventional vascular risk factors, especially hypertension and hyperlipidemia; smoking, diabetes, coronary disease, obesity, and other vascular risk factors are tracked and treated as part of risk-factor management.
Show evidence (2 references)
PMID:25977279 SUPPORT Human Clinical
"The cohort (n=72; 44% women) had a mean age of 65.6 years; 72% presented with ischemic stroke. Hypertension (93%) and hyperlipidemia (81%) were the most prevalent vascular risk factors."
This prospective cohort documents high prevalence of hypertension and hyperlipidemia in symptomatic vertebrobasilar disease.
PMID:21050408 SUPPORT Human Clinical
"The nature and frequency of cerebral ischemic events is recorded Medications at the time of enrollment and specific data regarding vascular risk factors are gathered including age, gender, race, hypertension, diabetes mellitus, lipid disorder, coronary disease, smoking, alcohol consumption, and..."
VERiTAS explicitly collected these as vascular risk factors in symptomatic vertebrobasilar disease.
Mechanism Target:
PREDISPOSES Atherosclerotic vertebral artery stenosis — Conventional vascular risk-factor burden predisposes to atherosclerotic vertebral artery disease, but this aggregate clinical evidence does not establish a uniform directness or intermediate sequence.
Show evidence (1 reference)
PMID:35301953 SUPPORT Human Clinical
"In addition, therapies are targeted at reducing atherosclerotic risk factors, such as hypertension, hyperlipidaemia, smoking, diabetes mellitus, and other lifestyle modifications are recommended for all patients with V.A. disease."
Identifies modifiable atherosclerotic risk factors in vertebral artery disease but does not directly observe the omitted plaque-development sequence.
PREDISPOSES Atherosclerotic basilar artery stenosis or occlusion — Conventional vascular risk-factor burden is associated with atherosclerotic basilar artery disease, but the mixed-cohort evidence does not establish site-specific causal directness.
Show evidence (1 reference)
PMID:25977279 SUPPORT Human Clinical
"The cohort (n=72; 44% women) had a mean age of 65.6 years; 72% presented with ischemic stroke. Hypertension (93%) and hyperlipidemia (81%) were the most prevalent vascular risk factors."
The selected mixed vertebral/basilar cohort documents high risk-factor prevalence but has no comparator and does not isolate a basilar causal effect.
PREDISPOSES Atherosclerotic vertebral artery occlusion — Conventional vascular risk-factor burden can predispose to atherosclerotic vertebral occlusion, but this aggregate evidence does not establish a uniform causal sequence to occlusion.
Show evidence (1 reference)
PMID:35301953 SUPPORT Human Clinical
"In addition, therapies are targeted at reducing atherosclerotic risk factors, such as hypertension, hyperlipidaemia, smoking, diabetes mellitus, and other lifestyle modifications are recommended for all patients with V.A. disease."
Identifies modifiable atherosclerotic risk factors in vertebral artery disease but does not directly observe progression from plaque to occlusion.
Cervical spine trauma
Cervical spine trauma can cause vertebral artery injury, which may lead to posterior-circulation stroke and can require conservative, antithrombotic, endovascular, or surgical management.
Show evidence (1 reference)
PMID:37924280 SUPPORT Human Clinical
"20-studies (n = 503) included data on trauma type; 75.5% (n = 380) suffered blunt trauma and 24.5% (n = 123) penetrating."
This supports trauma as an extrinsic cause category for vertebral artery injury.
Mechanism Target:
TRIGGERS Traumatic vertebral artery injury — Blunt or penetrating cervical trauma is the initiating exposure for traumatic vertebral artery injury.
Show evidence (1 reference)
PMID:37924280 SUPPORT Human Clinical
"20-studies (n = 503) included data on trauma type; 75.5% (n = 380) suffered blunt trauma and 24.5% (n = 123) penetrating."
The meta-analysis directly characterizes blunt and penetrating trauma among traumatic vertebral artery injury cases.
🔬

Diagnosis

3
Color Doppler duplex ultrasonography screening
Color Doppler or duplex ultrasonography is a noninvasive screening method for detecting and quantifying proximal vertebral artery stenosis, with positive or intervention-relevant findings typically requiring confirmatory angiographic imaging.
ultrasound imaging NCIT:C17230 NCI Thesaurus (NCIT)
Show evidence (2 references)
PMID:11385214 SUPPORT Human Clinical
"CONCLUSION: Duplex sonography should be proposed first in VB attacks or stroke to detect and quantify vertebral artery stenoses for surgery and angioplasty."
This directly supports duplex sonography as an early diagnostic test for vertebral artery stenosis in vertebrobasilar attacks or stroke.
PMID:36127977 SUPPORT Human Clinical
"Digital subtraction angiography (DSA) is considered the current gold standard in diagnosing vertebral artery stenosis; however, its associated morbidity and mortality have led to increased use of non-invasive techniques such as duplex ultrasonography (DUS), computed tomography angiography (CTA),..."
This review supports DUS as a noninvasive diagnostic technique used for vertebral artery stenosis.
Quantitative magnetic resonance angiography
QMRA can noninvasively measure large-vessel vertebrobasilar flow and help classify distal flow compromise in symptomatic vertebrobasilar disease.
magnetic resonance angiography procedure NCIT:C190557 NCI Thesaurus (NCIT)
Show evidence (1 reference)
PMID:21050408 SUPPORT Human Clinical
"The Vertebrobasilar Flow Evaluation and Risk of Transient Ischaemic Attack and Stroke (VERiTAS) study, a prospective multicentre NIH-funded observational study of symptomatic vertebrobasilar stenosis (≥50%) or occlusion, is designed to test the hypothesis that patients demonstrating compromised..."
This supports QMRA as a hemodynamic assessment tool for symptomatic vertebrobasilar stenosis or occlusion.
CT angiography and catheter angiography confirmation
CTA or conventional catheter angiography can confirm extracranial or intracranial vertebrobasilar stenosis or occlusion for clinical diagnosis or study eligibility.
contrast angiography procedure NCIT:C20080 NCI Thesaurus (NCIT)
Show evidence (1 reference)
PMID:21050408 SUPPORT Human Clinical
"Diagnostic evaluation is performed at the discretion of the treating physicians, but commonly includes: MRA, CT angiography (CTA), TCD or conventional angiography."
This supports CTA, MRA, TCD, and conventional angiography as diagnostic evaluations for suspected vertebrobasilar ischemia.
🔬

Clinical Trials

2
NCT05885932 NOT_APPLICABLE RECRUITING
Randomized multicenter trial of drug-eluting stenting plus best medical treatment versus best medical treatment alone for 70-99% extracranial vertebral artery stenosis causing recent stroke or TIA.
Target Phenotypes: transient ischemic attack HP:0002326 Human Phenotype Ontology (HP) Relation: this clinical trial targets this phenotype This clinical trial targets transient ischemic attack (HP:0002326). HP:0002326 is a phenotype from the Human Phenotype Ontology. ischemic stroke HP:0002140 Human Phenotype Ontology (HP) Relation: this clinical trial targets this phenotype This clinical trial targets ischemic stroke (HP:0002140). HP:0002140 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
clinicaltrials:NCT05885932 SUPPORT Human Clinical
"Patients will be randomized (1:1) to best medical treatment alone or medical treatment plus stenting."
This trial summary directly supports randomized comparison of medical therapy alone versus stenting plus medical therapy.
NCT03201432 NOT_APPLICABLE COMPLETED
Randomized trial comparing drug-eluting stents versus bare metal stents for symptomatic extracranial vertebral artery stenosis, focused on restenosis prevention after vertebral artery reconstruction.
Target Phenotypes: ischemic stroke HP:0002140 Human Phenotype Ontology (HP) Relation: this clinical trial targets this phenotype This clinical trial targets ischemic stroke (HP:0002140). HP:0002140 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
clinicaltrials:NCT03201432 SUPPORT Human Clinical
"Previous systematic review had suggested that the drug eluting stent might reduce the incidence of restenosis of vertebral artery."
This trial summary supports evaluation of stent type for restenosis prevention in symptomatic extracranial vertebral artery stenosis.
{ }

Source YAML

click to show 
name: Vertebral Artery Insufficiency
creation_date: "2026-05-06T19:00:20Z"
description: >-
  Vertebral artery insufficiency is a posterior-circulation vascular disorder in
  which vertebral or vertebrobasilar stenosis, occlusion, dissection, injury,
  hypoplasia with superimposed stenosis or limited collateral reserve, or
  extrinsic bony compression compromises perfusion or generates embolic ischemia
  in the brainstem, cerebellar, thalamic, or occipital circulation.
  Clinical presentations overlap with vertebrobasilar insufficiency,
  symptomatic vertebrobasilar disease, posterior-circulation transient ischemic
  attack, and posterior-circulation ischemic stroke.
category: Complex
disease_term:
  preferred_term: vertebral artery insufficiency
  term:
    id: MONDO:0001631
    label: vertebral artery insufficiency
parents:
- Vascular insufficiency disorder
- Arterial disorder
- Transient ischemic attack
synonyms:
- Vertebrobasilar insufficiency
- Vertebrobasilar disease
- Symptomatic vertebral artery stenosis
- Vertebral artery stenosis and occlusion
- Vertebral artery occlusive disease
- Posterior circulation ischemia due to vertebral artery disease
references:
- reference: PMID:35301953
  title: "Vertebral Artery Interventions: A Comprehensive Updated Review."
  found_in:
  - Vertebral_Artery_Insufficiency-deep-research-falcon.md
- reference: DOI:10.1111/j.1747-4949.2010.00528.x
  title: "Vertebrobasilar Flow Evaluation and Risk of Transient Ischaemic Attack and Stroke Study (Veritas): Rationale and Design"
  found_in:
  - Vertebral_Artery_Insufficiency-deep-research-falcon.md
- reference: DOI:10.3389/fneur.2023.1202565
  title: "Microsurgical revascularization of a symptomatic proximal vertebral artery: pilot experiences from a single center"
  found_in:
  - Vertebral_Artery_Insufficiency-deep-research-falcon.md
- reference: DOI:10.1177/17474930221107500
  title: "Treatment of posterior circulation stroke: Acute management and secondary prevention"
  found_in:
  - Vertebral_Artery_Insufficiency-deep-research-falcon.md
- reference: DOI:10.1161/str.0000000000000475
  title: "2024 Guideline for the Primary Prevention of Stroke: A Guideline From the American Heart Association/American Stroke Association"
  found_in:
  - Vertebral_Artery_Insufficiency-deep-research-falcon.md
- reference: DOI:10.1186/s12883-023-03110-z
  title: In-stent restenosis and stented-territory infarction after carotid and vertebrobasilar artery stenting
  found_in:
  - Vertebral_Artery_Insufficiency-deep-research-falcon.md
- reference: DOI:10.1007/s10143-024-03153-x
  title: "Application of microsurgical surgery in patients with proximal vertebral artery stenosis unsuited for endovascular treatment: a single-center retrospective study"
  found_in:
  - Vertebral_Artery_Insufficiency-deep-research-falcon.md
- reference: DOI:10.1177/21925682231209631
  title: A Systematic Review and Meta-Analysis of Vertebral Artery Injury After Cervical Spine Trauma
  found_in:
  - Vertebral_Artery_Insufficiency-deep-research-falcon.md
- reference: DOI:10.1186/s41983-024-00893-x
  title: "Vertebral artery dissection from etiopathogenesis to management therapy: a narrative review with neuroimaging's case illustration"
  found_in:
  - Vertebral_Artery_Insufficiency-deep-research-falcon.md
- reference: DOI:10.1161/strokeaha.115.009215
  title: Hemodynamic Features of Symptomatic Vertebrobasilar Disease
  found_in:
  - Vertebral_Artery_Insufficiency-deep-research-falcon.md
- reference: PMID:28680502
  title: "Pathophysiology and Diagnosis of Vertebrobasilar Insufficiency: A Review of the Literature."
- reference: PMID:11385214
  title: Accuracy of color-Doppler in the quantification of proximal vertebral artery stenoses.
- reference: PMID:36127977
  title: "Vertebral Artery Stenosis: A Narrative Review."
- reference: PMID:12870261
  title: "A case of intimal hyperplasia induced by stenting for vertebral artery origin stenosis: assessed on intravascular ultrasound."
pathophysiology:
- name: Atherosclerotic vertebral artery stenosis
  description: >-
    Atherosclerotic narrowing of extracranial or intracranial vertebral arteries
    is a major substrate for symptomatic vertebrobasilar disease. Percentage
    stenosis alone does not predict vertebral flow loss; severe bilateral or
    tandem disease, a small residual lumen, contralateral occlusion or
    hypoplasia, and limited collateral reserve can create hemodynamic compromise.
  biological_scale: TISSUE
  locations:
  - preferred_term: vertebral artery
    term:
      id: UBERON:0001535
      label: vertebral artery
  cell_types:
  - preferred_term: endothelial cell
    term:
      id: CL:0000115
      label: endothelial cell
  - preferred_term: vascular smooth muscle cell
    term:
      id: CL:0000192
      label: smooth muscle cell
  evidence:
  - reference: PMID:21050408
    reference_title: "Vertebrobasilar Flow Evaluation and Risk of Transient Ischaemic Attack and Stroke study (VERiTAS): rationale and design."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Over one-third of ischaemic strokes occur in the posterior circulation, and a leading cause is atherosclerotic vertebrobasilar disease.
    explanation: This identifies atherosclerotic disease encompassing vertebral lesions as a leading posterior-circulation ischemic stroke cause.
  - reference: PMID:25977279
    reference_title: Hemodynamic Features of Symptomatic Vertebrobasilar Disease.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Patients with recent vertebrobasilar transient ischemic attack or stroke and ≥50% atherosclerotic stenosis or occlusion in vertebral or basilar arteries (BA) were enrolled.
    explanation: The VERiTAS cohort explicitly included symptomatic atherosclerotic vertebral stenosis.
  - reference: PMID:25977279
    reference_title: Hemodynamic Features of Symptomatic Vertebrobasilar Disease.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The correlation between flow and the residual diameter at the site of stenosis was more robust and evident both in the BA (rho=0.65, p<0.01 for BA) and VA (rho=0.62, p<0.01) (Figure 1).
    explanation: Residual vertebral lumen, rather than percentage stenosis alone, is associated with local vertebral flow; this only partially supports the broader disease node.
  downstream:
  - target: Posterior circulation hypoperfusion
    description: Severe vertebral stenosis can contribute to distal hypoperfusion when residual lumen and compensatory inflow or collateral capacity are inadequate.
    causal_link_type: INDIRECT_KNOWN_INTERMEDIATES
    intermediate_mechanisms:
    - Reduced residual vertebral artery lumen
    - Bilateral or tandem vertebrobasilar disease
    - Contralateral occlusion or hypoplasia
    - Limited collateral reserve
    evidence:
    - reference: PMID:25977279
      reference_title: Hemodynamic Features of Symptomatic Vertebrobasilar Disease.
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        Tandem disease also had a significant impact on downstream flow: 43 ml/min in multifocal disease (concomitant BA and VA) compared to 71 ml/min in the patients with only BA or only VA disease (p=0.01).
      explanation: Supports reduced downstream flow in tandem disease but does not establish an unqualified vertebral-stenosis effect, so the link is indirect and partial.
    - reference: PMID:28680502
      reference_title: "Pathophysiology and Diagnosis of Vertebrobasilar Insufficiency: A Review of the Literature."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        The most frequent cause of the hemodynamic changes leading to VBI is atherosclerosis.
      explanation: Names atherosclerosis as a cause of hemodynamic compromise but does not isolate vertebral percentage stenosis or the omitted compensatory factors.
  - target: Vertebrobasilar thromboembolism
    description: Atherosclerotic stenosis can produce a low-flow state that promotes local thrombus formation.
    causal_link_type: INDIRECT_KNOWN_INTERMEDIATES
    intermediate_mechanisms:
    - Posterior-circulation low-flow state
    evidence:
    - reference: PMID:21050408
      reference_title: "Vertebrobasilar Flow Evaluation and Risk of Transient Ischaemic Attack and Stroke study (VERiTAS): rationale and design."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        Low flow may also promote local thrombus formation at the site of disease, with resultant stroke (3).
      explanation: >-
        Establishes low flow as the known intermediate between stenotic disease and
        local thrombosis; no direct plaque-embolism claim is made by this edge.
- name: Atherosclerotic vertebral artery occlusion
  description: >-
    Atherosclerotic vertebral artery occlusion is modeled separately from
    stenosis so interventions supported only for stenotic lesions do not export
    to chronic total occlusion. Occlusion can cause posterior-circulation
    ischemia, while its hemodynamic impact depends on the opposite vertebral
    artery and collateral circulation.
  biological_scale: TISSUE
  locations:
  - preferred_term: vertebral artery
    term:
      id: UBERON:0001535
      label: vertebral artery
  evidence:
  - reference: PMID:25977279
    reference_title: Hemodynamic Features of Symptomatic Vertebrobasilar Disease.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Patients with recent vertebrobasilar transient ischemic attack or stroke and ≥50% atherosclerotic stenosis or occlusion in vertebral or basilar arteries (BA) were enrolled.
    explanation: The adjudicated atherosclerotic cohort included symptomatic vertebral artery occlusion.
  - reference: PMID:35301953
    reference_title: "Vertebral Artery Interventions: A Comprehensive Updated Review."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Occlusion of the extracranial V.A. causes ischemia in the medulla and/or cerebellum and usually manifests as brief TIAs.
    explanation: Establishes the posterior-circulation ischemic consequence of extracranial vertebral occlusion.
  downstream:
  - target: Posterior circulation ischemia
    description: Vertebral artery occlusion can cause medullary or cerebellar ischemia and transient ischemic attacks.
    causal_link_type: DIRECT
    evidence:
    - reference: PMID:35301953
      reference_title: "Vertebral Artery Interventions: A Comprehensive Updated Review."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        Occlusion of the extracranial V.A. causes ischemia in the medulla and/or cerebellum and usually manifests as brief TIAs.
      explanation: Directly supports the occlusion-to-posterior-ischemia edge.
- name: Atherosclerotic basilar artery stenosis or occlusion
  description: >-
    Atherosclerotic narrowing or occlusion of the basilar artery is a distinct
    vertebrobasilar lesion that can reduce basilar and distal
    posterior-circulation flow. It is modeled separately so vertebral-artery
    interventions are not generalized to basilar disease.
  biological_scale: TISSUE
  locations:
  - preferred_term: basilar artery
    term:
      id: UBERON:0001633
      label: basilar artery
  cell_types:
  - preferred_term: endothelial cell
    term:
      id: CL:0000115
      label: endothelial cell
  - preferred_term: vascular smooth muscle cell
    term:
      id: CL:0000192
      label: smooth muscle cell
  evidence:
  - reference: PMID:25977279
    reference_title: Hemodynamic Features of Symptomatic Vertebrobasilar Disease.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Patients with recent vertebrobasilar transient ischemic attack or stroke and ≥50% atherosclerotic stenosis or occlusion in vertebral or basilar arteries (BA) were enrolled.
    explanation: The VERiTAS cohort explicitly included symptomatic atherosclerotic basilar stenosis or occlusion.
  - reference: PMID:25977279
    reference_title: Hemodynamic Features of Symptomatic Vertebrobasilar Disease.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      For the BA, the largest and most statistically significant drop in vessel flow was first encountered at a threshold of 80% stenosis (p=0.02)
    explanation: Quantifies basilar-artery flow loss at severe stenosis.
  downstream:
  - target: Posterior circulation hypoperfusion
    description: Severe basilar artery stenosis or occlusion can reduce distal posterior-circulation flow.
    causal_link_type: DIRECT
    evidence:
    - reference: PMID:25977279
      reference_title: Hemodynamic Features of Symptomatic Vertebrobasilar Disease.
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        BA flows correlated negatively with percentage stenosis in the affected vessel and positively to the minimal diameter at the stenosis site (P<0.01).
      explanation: Directly quantifies the basilar-stenosis-to-flow relationship represented by this edge.
- name: Posterior circulation hypoperfusion
  description: >-
    Low vertebrobasilar flow can impair perfusion reserve in posterior
    circulation territories. Quantitative magnetic resonance angiography (QMRA)
    is used in VERiTAS-style assessments to distinguish low from normal distal
    flow and to evaluate risk beyond anatomic stenosis alone.
  biological_scale: TISSUE
  locations:
  - preferred_term: brainstem
    term:
      id: UBERON:0002298
      label: brainstem
  - preferred_term: cerebellum
    term:
      id: UBERON:0002037
      label: cerebellum
  - preferred_term: occipital lobe
    term:
      id: UBERON:0002021
      label: occipital lobe
  evidence:
  - reference: PMID:21050408
    reference_title: "Vertebrobasilar Flow Evaluation and Risk of Transient Ischaemic Attack and Stroke study (VERiTAS): rationale and design."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Preliminary studies indicate that stroke risk in vertebrobasilar disease is strongly related to haemodynamic compromise, which can be measured noninvasively using quantitative magnetic resonance angiography.
    explanation: This supports hemodynamic compromise as an upstream risk mechanism measurable with QMRA.
  - reference: PMID:25977279
    reference_title: Hemodynamic Features of Symptomatic Vertebrobasilar Disease.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Flow in stenotic posterior circulation vessels correlates with residual diameter and drops significantly with tandem disease.
    explanation: This directly supports reduced flow downstream of posterior-circulation stenotic disease.
  downstream:
  - target: Posterior circulation ischemia
    description: Sustained or recurrent low flow can culminate in posterior-circulation TIA or infarction.
    causal_link_type: DIRECT
    evidence:
    - reference: PMID:21050408
      reference_title: "Vertebrobasilar Flow Evaluation and Risk of Transient Ischaemic Attack and Stroke study (VERiTAS): rationale and design."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        Preliminary studies indicate that stroke risk in vertebrobasilar disease is strongly related to haemodynamic compromise, which can be measured noninvasively using quantitative magnetic resonance angiography.
      explanation: Ties haemodynamic compromise to downstream stroke risk, which is the claim this edge makes.
- name: Vertebrobasilar thromboembolism
  description: >-
    Vertebrobasilar atherostenosis can produce ischemia by thromboembolism as
    well as by flow failure. Hypoperfusion may also reduce embolus washout and
    promote local thrombus formation at diseased arterial segments.
  biological_scale: TISSUE
  biological_processes:
  - preferred_term: blood coagulation
    modifier: INCREASED
    term:
      id: GO:0007596
      label: blood coagulation
  cell_types:
  - preferred_term: endothelial cell
    term:
      id: CL:0000115
      label: endothelial cell
  - preferred_term: platelet
    term:
      id: CL:0000233
      label: platelet
  evidence:
  - reference: PMID:21050408
    reference_title: "Vertebrobasilar Flow Evaluation and Risk of Transient Ischaemic Attack and Stroke study (VERiTAS): rationale and design."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Furthermore, both embolic and flow processes can synergize to increase stroke risk; a proposed mechanism is the reduced wash-out of emboli from the distal circulation in hypoperfused regions (6, 7). Low flow may also promote local thrombus formation at the site of disease, with resultant stroke (3).
    explanation: This supports mixed embolic and flow-mediated mechanisms linking vertebrobasilar disease to stroke.
  downstream:
  - target: Posterior circulation ischemia
    description: Emboli or local thrombosis can occlude posterior-circulation branches and cause transient or completed ischemia.
    causal_link_type: DIRECT
    evidence:
    - reference: PMID:21050408
      reference_title: "Vertebrobasilar Flow Evaluation and Risk of Transient Ischaemic Attack and Stroke study (VERiTAS): rationale and design."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        Furthermore, both embolic and flow processes can synergize to increase stroke risk; a proposed mechanism is the reduced wash-out of emboli from the distal circulation in hypoperfused regions (6, 7).
      explanation: Supports embolic processes culminating in posterior-circulation stroke, including synergy with hypoperfusion.
- name: Vertebral artery dissection
  description: >-
    Vertebral artery dissection begins with a wall tear and mural blood entry
    and can compromise the lumen through stenosis, occlusion, or thrombosis.
    It is modeled separately from other traumatic vertebral injuries because
    the headache and neck-pain evidence is specific to dissection.
  biological_scale: TISSUE
  locations:
  - preferred_term: vertebral artery
    term:
      id: UBERON:0001535
      label: vertebral artery
  evidence:
  - reference: DOI:10.1186/s41983-024-00893-x
    reference_title: "Vertebral artery dissection from etiopathogenesis to management therapy: a narrative review with neuroimaging’s case illustration"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Vertebral artery dissection occurs due to a tear in the vertebral artery wall, which results in blood flow entering the blood vessel wall.
    explanation: This supports mural dissection as a vertebral artery mechanism that can lead to insufficiency or ischemia.
  downstream:
  - target: Posterior circulation ischemia
    description: Vertebral artery dissection can cause posterior-circulation TIA or stroke through thrombosis or stenosis-driven hypoperfusion.
    causal_link_type: INDIRECT_KNOWN_INTERMEDIATES
    intermediate_mechanisms:
    - Dissection-associated thrombosis or thromboembolism
    - Stenosis-associated hypoperfusion
    evidence:
    - reference: DOI:10.1186/s41983-024-00893-x
      reference_title: "Vertebral artery dissection from etiopathogenesis to management therapy: a narrative review with neuroimaging’s case illustration"
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        Thrombosis between the arteries is the most common cause of stroke-like symptoms in VAD, followed by hypoperfusion due to stenosis.
      explanation: Names the two known intermediate routes by which dissection reaches the ischemia node.
  - target: Headache
    description: Vertebral artery dissection can directly present with headache.
    causal_link_type: DIRECT
    evidence:
    - reference: DOI:10.1186/s41983-024-00893-x
      reference_title: "Vertebral artery dissection from etiopathogenesis to management therapy: a narrative review with neuroimaging’s case illustration"
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        The most frequent clinical manifestations include stroke, transient ischemic attack, neck pain, headaches, and vertigo.
      explanation: Links the dissection mechanism to its headache manifestation.
  - target: Neck pain
    description: Vertebral artery dissection can directly present with neck pain.
    causal_link_type: DIRECT
    evidence:
    - reference: DOI:10.1186/s41983-024-00893-x
      reference_title: "Vertebral artery dissection from etiopathogenesis to management therapy: a narrative review with neuroimaging’s case illustration"
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        The most frequent clinical manifestations include stroke, transient ischemic attack, neck pain, headaches, and vertigo.
      explanation: Links the dissection mechanism to its neck-pain manifestation.
- name: Traumatic vertebral artery injury
  description: >-
    Blunt or penetrating cervical trauma can injure the vertebral artery and is
    associated with posterior-circulation stroke. The available meta-analysis
    quantifies that outcome but does not establish a direct transition, so
    vascular luminal compromise and thromboembolism remain known omitted
    intermediates.
  biological_scale: TISSUE
  locations:
  - preferred_term: vertebral artery
    term:
      id: UBERON:0001535
      label: vertebral artery
  evidence:
  - reference: PMID:37924280
    reference_title: A Systematic Review and Meta-Analysis of Vertebral Artery Injury After Cervical Spine Trauma.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      VAI in cervical spine trauma has an approximate posterior circulation stroke risk of 9%.
    explanation: This meta-analysis quantifies posterior-circulation stroke risk after traumatic vertebral artery injury.
  downstream:
  - target: Posterior circulation ischemia
    description: Traumatic vertebral artery injury is associated with posterior stroke through omitted vascular-lesion and thromboembolic mechanisms.
    causal_link_type: INDIRECT_KNOWN_INTERMEDIATES
    intermediate_mechanisms:
    - Trauma-induced vertebral artery stenosis or occlusion
    - Thromboembolism
    evidence:
    - reference: PMID:37924280
      reference_title: A Systematic Review and Meta-Analysis of Vertebral Artery Injury After Cervical Spine Trauma.
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        From the 16 studies which reported data on outcomes, 8.87% (95% CI 5.34- 12.99) of patients with VAI had a posterior stroke.
      explanation: Quantifies the injury-stroke association but does not establish the omitted intermediate sequence, so support is partial.
- name: Extrinsic bony compression of the vertebral artery
  description: >-
    Mechanical compression of the vertebral artery by adjacent bone is a
    non-atherosclerotic, structural route to vertebral artery stenosis. Because
    the vessel traverses the cervical transverse foramina, osteophytes and other
    bony encroachment can narrow the lumen. The cited review establishes bony
    compression as one of several
    non-atherosclerotic stenosis etiologies; it does not characterize
    position-dependent or rotational compression, so no dynamic-compression
    claim is asserted here.
  biological_scale: TISSUE
  locations:
  - preferred_term: vertebral artery
    term:
      id: UBERON:0001535
      label: vertebral artery
  evidence:
  - reference: PMID:36127977
    reference_title: "Vertebral Artery Stenosis: A Narrative Review."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Mechanical compression of the vertebral artery by bone can also cause stenosis of the vertebral artery.
    explanation: This review establishes bony compression as a distinct, non-atherosclerotic cause of vertebral artery stenosis.
  - reference: PMID:36127977
    reference_title: "Vertebral Artery Stenosis: A Narrative Review."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      There are several causes of vertebral artery stenosis, including atherosclerosis, calcification, dissections, fibromuscular dysplasia, giant cell arteritis, neurofibromatosis type 1, and bony compressions.
    explanation: This enumerates bony compression alongside atherosclerosis and dissection as a recognized stenosis etiology, supporting it as a separate mechanism node.
  downstream:
  - target: Posterior circulation hypoperfusion
    description: >-
      Bony encroachment can cause vertebral stenosis, which is the known omitted
      intermediate through which distal posterior-circulation flow may fall.
    causal_link_type: INDIRECT_KNOWN_INTERMEDIATES
    intermediate_mechanisms:
    - Compression-induced vertebral artery stenosis
    evidence:
    - reference: PMID:36127977
      reference_title: "Vertebral Artery Stenosis: A Narrative Review."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        Mechanical compression of the vertebral artery by bone can also cause stenosis of the vertebral artery.
      explanation: >-
        Establishes compression-induced stenosis as the known intermediate; the
        source does not itself establish a direct compression-to-flow transition.
- name: Vertebral artery hypoplasia
  description: >-
    Congenital hypoplasia produces a smaller-caliber vertebral artery. It is not
    itself sufficient to cause vertebrobasilar insufficiency, but a superimposed
    stenosis leaves a smaller residual lumen in a hypoplastic artery than the same
    percentage stenosis in a dominant artery.
  biological_scale: TISSUE
  locations:
  - preferred_term: vertebral artery
    term:
      id: UBERON:0001535
      label: vertebral artery
  evidence:
  - reference: PMID:12870261
    reference_title: "A case of intimal hyperplasia induced by stenting for vertebral artery origin stenosis: assessed on intravascular ultrasound."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Angiography revealed hypoplasia of left vertebral artery (VA) and remarkable stenosis of the proximal right VA with inadequate collateral flow from the anterior circulation.
    explanation: This documents contralateral hypoplasia plus inadequate anterior-circulation collateral flow as the anatomical context in which unilateral stenosis became symptomatic; case-level evidence only.
  - reference: PMID:40951011
    reference_title: "Critical Vertebrobasilar Insufficiency From Left Intracranial Vertebral Artery Stenosis With Contralateral Hypoplasia Presenting as Recurring Vertigo: Urgent Stenting to Prevent the Progression of a Posterior Circulation Stroke."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      CTA revealed severe stenosis of the left vertebral artery V4 segment, with a hypoplastic right vertebral artery.
    explanation: A second case pairing a hypoplastic contralateral vertebral artery with symptomatic stenosis, supporting reduced collateral reserve as a modifying substrate; case-level evidence only.
  - reference: PMID:25977279
    reference_title: Hemodynamic Features of Symptomatic Vertebrobasilar Disease.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      the same % stenosis leads to a markedly smaller residual diameter in a hypoplastic 2 mm vertebral compared to a dominant 5 mm VA
    explanation: Directly distinguishes the smaller residual lumen produced when stenosis affects a hypoplastic rather than dominant vertebral artery.
  downstream:
  - target: Posterior circulation hypoperfusion
    description: >-
      With superimposed stenosis, a hypoplastic vertebral artery has a smaller
      residual lumen; stenosis and residual-lumen restriction are known
      intermediates between the congenital caliber variant and distal flow loss.
    causal_link_type: INDIRECT_KNOWN_INTERMEDIATES
    intermediate_mechanisms:
    - Superimposed vertebral artery stenosis
    - Reduced residual lumen
    evidence:
    - reference: PMID:25977279
      reference_title: Hemodynamic Features of Symptomatic Vertebrobasilar Disease.
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        the same % stenosis leads to a markedly smaller residual diameter in a hypoplastic 2 mm vertebral compared to a dominant 5 mm VA
      explanation: >-
        Supports the residual-lumen intermediate but not hypoplasia as a sufficient
        direct cause of distal hypoperfusion, so the edge remains partial and indirect.
- name: Limited posterior-circulation collateral capacity
  description: >-
    Limited compensatory supply through contralateral vertebral and
    posterior-circulation collateral pathways can leave distal flow low despite
    similar local stenosis severity. This regional hemodynamic state is distinct
    from vertebral artery hypoplasia and from the local stenotic lesion.
  biological_scale: TISSUE
  locations:
  - preferred_term: vertebral artery
    term:
      id: UBERON:0001535
      label: vertebral artery
  - preferred_term: basilar artery
    term:
      id: UBERON:0001633
      label: basilar artery
  evidence:
  - reference: PMID:12870261
    reference_title: "A case of intimal hyperplasia induced by stenting for vertebral artery origin stenosis: assessed on intravascular ultrasound."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Angiography revealed hypoplasia of left vertebral artery (VA) and remarkable stenosis of the proximal right VA with inadequate collateral flow from the anterior circulation.
    explanation: Case-level evidence documents inadequate anterior-circulation collateral flow separately from the vertebral lesions.
  - reference: PMID:25977279
    reference_title: Hemodynamic Features of Symptomatic Vertebrobasilar Disease.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      hemodynamic assessment of the distal flow status in the posterior circulation, which incorporates the contribution of any large vessel collateral flow, is not well predicted by either the severity or location of the disease
    explanation: Establishes collateral-integrated distal flow as a regional hemodynamic property distinct from local stenosis severity and location.
  downstream:
  - target: Posterior circulation hypoperfusion
    description: Inadequate collateral contribution is a determinant of low regional distal flow.
    causal_link_type: DIRECT
    evidence:
    - reference: PMID:25977279
      reference_title: Hemodynamic Features of Symptomatic Vertebrobasilar Disease.
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        Conceptually, the algorithm incorporates any sources of collateral flow (e.g. via the posterior communicating arteries) by their effect on the blood flow within these distal vessels.
      explanation: Directly states that collateral sources affect distal-vessel blood flow, the relationship represented by this edge.
- name: Posterior circulation ischemia
  description: >-
    Final common ischemic injury occurs when hemodynamic compromise or
    thromboembolism reduces oxygen delivery to brainstem, cerebellar, thalamic,
    or occipital territories, causing transient ischemic attacks, ischemic
    stroke, or recurrent posterior-circulation symptoms.
  biological_scale: TISSUE
  locations:
  - preferred_term: brainstem
    term:
      id: UBERON:0002298
      label: brainstem
  - preferred_term: cerebellum
    term:
      id: UBERON:0002037
      label: cerebellum
  - preferred_term: occipital lobe
    term:
      id: UBERON:0002021
      label: occipital lobe
  evidence:
  - reference: PMID:35301953
    reference_title: "Vertebral Artery Interventions: A Comprehensive Updated Review."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Patients with posterior circulation ischemia due to vertebral artery stenosis account for 20 to 25% of ischemic strokes and have an increased risk of recurrent stroke.
    explanation: This directly links vertebral artery stenosis to posterior-circulation ischemia and ischemic stroke burden.
  downstream:
  - target: Vertigo
    description: Posterior-circulation ischemia can manifest clinically as vertigo.
    causal_link_type: DIRECT
    evidence:
    - reference: PMID:40148099
      reference_title: "Signs and symptoms of vertebrobasilar insufficiency secondary to atherosclerosis: a systematic review."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        Vertigo was the most common reported symptom, within a total of 37 different symptoms reported either in isolation or combination.
      explanation: Links vertebrobasilar insufficiency to the curated vertigo phenotype.
  - target: Transient ischemic attack
    description: Transient posterior-circulation ischemia manifests as vertebrobasilar TIA.
    causal_link_type: DIRECT
    evidence:
    - reference: PMID:25977279
      reference_title: Hemodynamic Features of Symptomatic Vertebrobasilar Disease.
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        METHODS: Patients with recent vertebrobasilar transient ischemic attack or stroke and ≥50% atherosclerotic stenosis or occlusion in vertebral or basilar arteries (BA) were enrolled.
      explanation: Links symptomatic vertebrobasilar ischemia to the TIA phenotype.
  - target: Ataxia
    description: Cerebellar or brainstem ischemia can manifest as ataxia.
    causal_link_type: DIRECT
    evidence:
    - reference: PMID:28680502
      reference_title: "Pathophysiology and Diagnosis of Vertebrobasilar Insufficiency: A Review of the Literature."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        Dizziness, vertigo, headaches, vomit, diplopia, blindness, ataxia, imbalance, and weakness in both sides of the body are the most common symptoms.
      explanation: Links vertebrobasilar insufficiency to the curated ataxia phenotype.
  - target: Diplopia
    description: Posterior-circulation ischemia involving ocular motor pathways can manifest as diplopia.
    causal_link_type: DIRECT
    evidence:
    - reference: PMID:28680502
      reference_title: "Pathophysiology and Diagnosis of Vertebrobasilar Insufficiency: A Review of the Literature."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        Dizziness, vertigo, headaches, vomit, diplopia, blindness, ataxia, imbalance, and weakness in both sides of the body are the most common symptoms.
      explanation: Links vertebrobasilar insufficiency to the curated diplopia phenotype.
  - target: Dysarthria
    description: Posterior-circulation neurologic dysfunction can manifest as dysarthria.
    causal_link_type: DIRECT
    evidence:
    - reference: PMID:12870261
      reference_title: "A case of intimal hyperplasia induced by stenting for vertebral artery origin stenosis: assessed on intravascular ultrasound."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        A 69-year-old man was admitted because of dysarthria and dysphagia. Angiography revealed hypoplasia of left vertebral artery (VA) and remarkable stenosis of the proximal right VA with inadequate collateral flow from the anterior circulation.
      explanation: Case-level evidence links symptomatic vertebral-artery flow compromise to dysarthria.
  - target: Dysphagia
    description: Brainstem or lower cranial nerve dysfunction from posterior-circulation ischemia can manifest as dysphagia.
    causal_link_type: DIRECT
    evidence:
    - reference: PMID:12870261
      reference_title: "A case of intimal hyperplasia induced by stenting for vertebral artery origin stenosis: assessed on intravascular ultrasound."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        A 69-year-old man was admitted because of dysarthria and dysphagia. Angiography revealed hypoplasia of left vertebral artery (VA) and remarkable stenosis of the proximal right VA with inadequate collateral flow from the anterior circulation.
      explanation: Case-level evidence links symptomatic vertebral-artery flow compromise to dysphagia.
  - target: Ischemic stroke
    description: Persistent posterior-circulation ischemia can culminate in ischemic stroke.
    causal_link_type: DIRECT
    evidence:
    - reference: PMID:35301953
      reference_title: "Vertebral Artery Interventions: A Comprehensive Updated Review."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        Patients with posterior circulation ischemia due to vertebral artery stenosis account for 20 to 25% of ischemic strokes and have an increased risk of recurrent stroke.
      explanation: Directly links posterior-circulation ischemia to the ischemic-stroke phenotype.
phenotypes:
- category: Cardiovascular
  name: Abnormal vertebral artery morphology
  diagnostic: true
  description: >-
    Structural or luminal vertebral artery abnormalities, including stenosis,
    occlusion, dissection, traumatic injury, or hypoplasia, are defining vascular
    abnormalities. Collateral flow is a separate hemodynamic state, not a
    vertebral-artery morphology.
  phenotype_term:
    preferred_term: abnormal vertebral artery morphology
    term:
      id: HP:0030321
      label: Abnormal vertebral artery morphology
  evidence:
  - reference: PMID:12870261
    reference_title: "A case of intimal hyperplasia induced by stenting for vertebral artery origin stenosis: assessed on intravascular ultrasound."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Angiography revealed hypoplasia of left vertebral artery (VA) and remarkable stenosis of the proximal right VA with inadequate collateral flow from the anterior circulation.
    explanation: Case-level angiography directly documents hypoplasia and stenosis of the vertebral arteries; basilar lesions and collateral flow are not classified as vertebral morphology here.
- category: Neurological
  name: Vertigo
  description: >-
    Vertigo is a common symptom of atherosclerotic vertebrobasilar
    insufficiency and can present as recurrent episodic vertigo when vertebral
    artery stenosis and limited collateral flow threaten the posterior
    circulation.
  phenotype_term:
    preferred_term: vertigo
    term:
      id: HP:0002321
      label: Vertigo
    temporality: RECURRENT
  evidence:
  - reference: PMID:40148099
    reference_title: "Signs and symptoms of vertebrobasilar insufficiency secondary to atherosclerosis: a systematic review."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Vertigo was the most common reported symptom, within a total of 37 different symptoms reported either in isolation or combination.
    explanation: This systematic review supports vertigo as the most common reported symptom in atherosclerotic VBI cases.
  - reference: PMID:40951011
    reference_title: "Critical Vertebrobasilar Insufficiency From Left Intracranial Vertebral Artery Stenosis With Contralateral Hypoplasia Presenting as Recurring Vertigo: Urgent Stenting to Prevent the Progression of a Posterior Circulation Stroke."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      This case emphasizes that recurrent atypical vertigo and brief syncope may be warning signs of vertebrobasilar insufficiency, especially in the context of vertebral artery stenosis with limited collateral flow.
    explanation: This case report supports recurrent vertigo as a warning symptom in a vertebral stenosis and hypoplastic collateral-flow presentation, but case-level evidence is indirect for population frequency.
- category: Neurological
  name: Transient ischemic attack
  description: >-
    Reversible posterior-circulation neurologic deficits can occur when
    vertebrobasilar flow or embolic protection is transiently inadequate.
  phenotype_term:
    preferred_term: transient ischemic attack
    term:
      id: HP:0002326
      label: Transient ischemic attack
    temporality: TRANSIENT
  evidence:
  - reference: PMID:25977279
    reference_title: Hemodynamic Features of Symptomatic Vertebrobasilar Disease.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      METHODS: Patients with recent vertebrobasilar transient ischemic attack or stroke and ≥50% atherosclerotic stenosis or occlusion in vertebral or basilar arteries (BA) were enrolled.
    explanation: This directly identifies recent vertebrobasilar TIA as a qualifying clinical presentation in symptomatic vertebrobasilar stenosis or occlusion.
  - reference: DOI:10.1186/s41983-024-00893-x
    reference_title: "Vertebral artery dissection from etiopathogenesis to management therapy: a narrative review with neuroimaging’s case illustration"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The most frequent clinical manifestations include stroke, transient ischemic attack, neck pain, headaches, and vertigo.
    explanation: This supports TIA among common manifestations in dissection-associated vertebral artery disease.
- category: Neurological
  name: Ataxia
  description: >-
    Cerebellar or brainstem ischemia in vertebrobasilar insufficiency can
    manifest as impaired coordination or imbalance.
  phenotype_term:
    preferred_term: ataxia
    term:
      id: HP:0001251
      label: Ataxia
  evidence:
  - reference: PMID:28680502
    reference_title: "Pathophysiology and Diagnosis of Vertebrobasilar Insufficiency: A Review of the Literature."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Dizziness, vertigo, headaches, vomit, diplopia, blindness, ataxia, imbalance, and weakness in both sides of the body are the most common symptoms.
    explanation: This review identifies ataxia as a common symptom of vertebrobasilar insufficiency.
- category: Neurological
  name: Diplopia
  description: >-
    Posterior-circulation ischemia can affect ocular motor pathways and present
    with double vision.
  phenotype_term:
    preferred_term: diplopia
    term:
      id: HP:0000651
      label: Diplopia
  evidence:
  - reference: PMID:28680502
    reference_title: "Pathophysiology and Diagnosis of Vertebrobasilar Insufficiency: A Review of the Literature."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Dizziness, vertigo, headaches, vomit, diplopia, blindness, ataxia, imbalance, and weakness in both sides of the body are the most common symptoms.
    explanation: This review identifies diplopia as a common symptom of vertebrobasilar insufficiency.
- category: Neurological
  name: Dysarthria
  description: >-
    Vertebral artery stenosis with inadequate collateral flow can produce
    posterior-circulation neurologic deficits including impaired articulation.
  phenotype_term:
    preferred_term: dysarthria
    term:
      id: HP:0001260
      label: Dysarthria
  evidence:
  - reference: PMID:12870261
    reference_title: "A case of intimal hyperplasia induced by stenting for vertebral artery origin stenosis: assessed on intravascular ultrasound."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      A 69-year-old man was admitted because of dysarthria and dysphagia. Angiography revealed hypoplasia of left vertebral artery (VA) and remarkable stenosis of the proximal right VA with inadequate collateral flow from the anterior circulation.
    explanation: This vertebral artery origin stenosis case supports dysarthria as a posterior-circulation symptom, but the evidence is case-level.
- category: Neurological
  name: Dysphagia
  description: >-
    Brainstem or lower cranial nerve involvement in vertebrobasilar ischemia can
    present with impaired swallowing.
  phenotype_term:
    preferred_term: dysphagia
    term:
      id: HP:0002015
      label: Dysphagia
  evidence:
  - reference: PMID:12870261
    reference_title: "A case of intimal hyperplasia induced by stenting for vertebral artery origin stenosis: assessed on intravascular ultrasound."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      A 69-year-old man was admitted because of dysarthria and dysphagia. Angiography revealed hypoplasia of left vertebral artery (VA) and remarkable stenosis of the proximal right VA with inadequate collateral flow from the anterior circulation.
    explanation: This vertebral artery origin stenosis case supports dysphagia as a posterior-circulation symptom, but the evidence is case-level.
- category: Neurological
  name: Ischemic stroke
  description: >-
    Persistent posterior-circulation ischemia can cause infarction in
    vertebrobasilar territories and carries substantial early recurrence risk.
  phenotype_term:
    preferred_term: ischemic stroke
    term:
      id: HP:0002140
      label: Ischemic stroke
  evidence:
  - reference: PMID:35301953
    reference_title: "Vertebral Artery Interventions: A Comprehensive Updated Review."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Patients with posterior circulation ischemia due to vertebral artery stenosis account for 20 to 25% of ischemic strokes and have an increased risk of recurrent stroke.
    explanation: This directly links vertebral artery stenosis-related posterior circulation ischemia to ischemic stroke burden.
  - reference: PMID:37924280
    reference_title: A Systematic Review and Meta-Analysis of Vertebral Artery Injury After Cervical Spine Trauma.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      From the 16 studies which reported data on outcomes, 8.87% (95% CI 5.34- 12.99) of patients with VAI had a posterior stroke.
    explanation: This meta-analysis supports posterior stroke as an outcome in trauma-associated vertebral artery injury.
- category: Neurological
  name: Headache
  description: >-
    Headache can occur in dissection-associated vertebral artery presentations,
    particularly alongside neck pain, vertigo, TIA, or stroke.
  phenotype_term:
    preferred_term: headache
    term:
      id: HP:0002315
      label: Headache
  evidence:
  - reference: DOI:10.1186/s41983-024-00893-x
    reference_title: "Vertebral artery dissection from etiopathogenesis to management therapy: a narrative review with neuroimaging’s case illustration"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The most frequent clinical manifestations include stroke, transient ischemic attack, neck pain, headaches, and vertigo.
    explanation: This review supports headache as a frequent manifestation in vertebral artery dissection.
- category: Musculoskeletal
  name: Neck pain
  description: >-
    Neck pain is a common symptom in dissection-associated vertebral artery
    disease and can accompany posterior-circulation ischemic events.
  phenotype_term:
    preferred_term: neck pain
    term:
      id: HP:0030833
      label: Neck pain
  evidence:
  - reference: DOI:10.1186/s41983-024-00893-x
    reference_title: "Vertebral artery dissection from etiopathogenesis to management therapy: a narrative review with neuroimaging’s case illustration"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The most frequent clinical manifestations include stroke, transient ischemic attack, neck pain, headaches, and vertigo.
    explanation: This review supports neck pain as a frequent manifestation in vertebral artery dissection.
environmental:
- name: Atherosclerotic vascular risk factor burden
  description: >-
    Symptomatic vertebrobasilar disease cohorts have a high prevalence of
    conventional vascular risk factors, especially hypertension and
    hyperlipidemia; smoking, diabetes, coronary disease, obesity, and other
    vascular risk factors are tracked and treated as part of risk-factor
    management.
  influences_mechanisms:
  - target: Atherosclerotic vertebral artery stenosis
    environmental_effect: PREDISPOSES
    causal_link_type: UNKNOWN
    description: Conventional vascular risk-factor burden predisposes to atherosclerotic vertebral artery disease, but this aggregate clinical evidence does not establish a uniform directness or intermediate sequence.
    evidence:
    - reference: PMID:35301953
      reference_title: "Vertebral Artery Interventions: A Comprehensive Updated Review."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        In addition, therapies are targeted at reducing atherosclerotic risk factors, such as hypertension, hyperlipidaemia, smoking, diabetes mellitus, and other lifestyle modifications are recommended for all patients with V.A. disease.
      explanation: Identifies modifiable atherosclerotic risk factors in vertebral artery disease but does not directly observe the omitted plaque-development sequence.
  - target: Atherosclerotic basilar artery stenosis or occlusion
    environmental_effect: PREDISPOSES
    causal_link_type: UNKNOWN
    description: Conventional vascular risk-factor burden is associated with atherosclerotic basilar artery disease, but the mixed-cohort evidence does not establish site-specific causal directness.
    evidence:
    - reference: PMID:25977279
      reference_title: Hemodynamic Features of Symptomatic Vertebrobasilar Disease.
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        The cohort (n=72; 44% women) had a mean age of 65.6 years; 72% presented with ischemic stroke. Hypertension (93%) and hyperlipidemia (81%) were the most prevalent vascular risk factors.
      explanation: The selected mixed vertebral/basilar cohort documents high risk-factor prevalence but has no comparator and does not isolate a basilar causal effect.
  - target: Atherosclerotic vertebral artery occlusion
    environmental_effect: PREDISPOSES
    causal_link_type: UNKNOWN
    description: Conventional vascular risk-factor burden can predispose to atherosclerotic vertebral occlusion, but this aggregate evidence does not establish a uniform causal sequence to occlusion.
    evidence:
    - reference: PMID:35301953
      reference_title: "Vertebral Artery Interventions: A Comprehensive Updated Review."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        In addition, therapies are targeted at reducing atherosclerotic risk factors, such as hypertension, hyperlipidaemia, smoking, diabetes mellitus, and other lifestyle modifications are recommended for all patients with V.A. disease.
      explanation: Identifies modifiable atherosclerotic risk factors in vertebral artery disease but does not directly observe progression from plaque to occlusion.
  evidence:
  - reference: PMID:25977279
    reference_title: Hemodynamic Features of Symptomatic Vertebrobasilar Disease.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The cohort (n=72; 44% women) had a mean age of 65.6 years; 72% presented with ischemic stroke. Hypertension (93%) and hyperlipidemia (81%) were the most prevalent vascular risk factors.
    explanation: This prospective cohort documents high prevalence of hypertension and hyperlipidemia in symptomatic vertebrobasilar disease.
  - reference: PMID:21050408
    reference_title: "Vertebrobasilar Flow Evaluation and Risk of Transient Ischaemic Attack and Stroke study (VERiTAS): rationale and design."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The nature and frequency of cerebral ischemic events is recorded Medications at the time of enrollment and specific data regarding vascular risk factors are gathered including age, gender, race, hypertension, diabetes mellitus, lipid disorder, coronary disease, smoking, alcohol consumption, and parental death from stroke.
    explanation: VERiTAS explicitly collected these as vascular risk factors in symptomatic vertebrobasilar disease.
- name: Cervical spine trauma
  description: >-
    Cervical spine trauma can cause vertebral artery injury, which may lead to
    posterior-circulation stroke and can require conservative, antithrombotic,
    endovascular, or surgical management.
  influences_mechanisms:
  - target: Traumatic vertebral artery injury
    environmental_effect: TRIGGERS
    causal_link_type: DIRECT
    description: Blunt or penetrating cervical trauma is the initiating exposure for traumatic vertebral artery injury.
    evidence:
    - reference: PMID:37924280
      reference_title: A Systematic Review and Meta-Analysis of Vertebral Artery Injury After Cervical Spine Trauma.
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        20-studies (n = 503) included data on trauma type; 75.5% (n = 380) suffered blunt trauma and 24.5% (n = 123) penetrating.
      explanation: The meta-analysis directly characterizes blunt and penetrating trauma among traumatic vertebral artery injury cases.
  evidence:
  - reference: PMID:37924280
    reference_title: A Systematic Review and Meta-Analysis of Vertebral Artery Injury After Cervical Spine Trauma.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      20-studies (n = 503) included data on trauma type; 75.5% (n = 380) suffered blunt trauma and 24.5% (n = 123) penetrating.
    explanation: This supports trauma as an extrinsic cause category for vertebral artery injury.
diagnosis:
- name: Color Doppler duplex ultrasonography screening
  diagnosis_term:
    preferred_term: ultrasound imaging
    term:
      id: NCIT:C17230
      label: Ultrasound Imaging
  description: >-
    Color Doppler or duplex ultrasonography is a noninvasive screening method
    for detecting and quantifying proximal vertebral artery stenosis, with
    positive or intervention-relevant findings typically requiring confirmatory
    angiographic imaging.
  evidence:
  - reference: PMID:11385214
    reference_title: Accuracy of color-Doppler in the quantification of proximal vertebral artery stenoses.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      CONCLUSION: Duplex sonography should be proposed first in VB attacks or stroke to detect and quantify vertebral artery stenoses for surgery and angioplasty.
    explanation: This directly supports duplex sonography as an early diagnostic test for vertebral artery stenosis in vertebrobasilar attacks or stroke.
  - reference: PMID:36127977
    reference_title: "Vertebral Artery Stenosis: A Narrative Review."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Digital subtraction angiography (DSA) is considered the current gold standard in diagnosing vertebral artery stenosis; however, its associated morbidity and mortality have led to increased use of non-invasive techniques such as duplex ultrasonography (DUS), computed tomography angiography (CTA), and magnetic resonance angiography (MRA).
    explanation: This review supports DUS as a noninvasive diagnostic technique used for vertebral artery stenosis.
- name: Quantitative magnetic resonance angiography
  diagnosis_term:
    preferred_term: magnetic resonance angiography procedure
    term:
      id: NCIT:C190557
      label: Magnetic Resonance Angiography
  description: >-
    QMRA can noninvasively measure large-vessel vertebrobasilar flow and help
    classify distal flow compromise in symptomatic vertebrobasilar disease.
  evidence:
  - reference: PMID:21050408
    reference_title: "Vertebrobasilar Flow Evaluation and Risk of Transient Ischaemic Attack and Stroke study (VERiTAS): rationale and design."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The Vertebrobasilar Flow Evaluation and Risk of Transient Ischaemic Attack and Stroke (VERiTAS) study, a prospective multicentre NIH-funded observational study of symptomatic vertebrobasilar stenosis (≥50%) or occlusion, is designed to test the hypothesis that patients demonstrating compromised blood flow as assessed by quantitative magnetic resonance angiography are at higher stroke risk.
    explanation: This supports QMRA as a hemodynamic assessment tool for symptomatic vertebrobasilar stenosis or occlusion.
- name: CT angiography and catheter angiography confirmation
  diagnosis_term:
    preferred_term: contrast angiography procedure
    term:
      id: NCIT:C20080
      label: X-ray Angiography
  description: >-
    CTA or conventional catheter angiography can confirm extracranial or
    intracranial vertebrobasilar stenosis or occlusion for clinical diagnosis
    or study eligibility.
  evidence:
  - reference: PMID:21050408
    reference_title: "Vertebrobasilar Flow Evaluation and Risk of Transient Ischaemic Attack and Stroke study (VERiTAS): rationale and design."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Diagnostic evaluation is performed at the discretion of the treating physicians, but commonly includes: MRA, CT angiography (CTA), TCD or conventional angiography.
    explanation: This supports CTA, MRA, TCD, and conventional angiography as diagnostic evaluations for suspected vertebrobasilar ischemia.
treatments:
- name: Aggressive medical secondary prevention
  description: >-
    Standard medical management focuses on antithrombotic therapy, statins, and
    intensive cerebrovascular risk-factor control. For high-risk minor posterior
    circulation stroke or TIA, short-term dual antiplatelet therapy may be used
    before transition to monotherapy.
  treatment_term:
    preferred_term: Pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
    therapeutic_agent:
    - preferred_term: aspirin
      term:
        id: CHEBI:15365
        label: acetylsalicylic acid
    - preferred_term: statin
      term:
        id: CHEBI:87631
        label: statin
  target_phenotypes:
  - preferred_term: transient ischemic attack
    term:
      id: HP:0002326
      label: Transient ischemic attack
  - preferred_term: ischemic stroke
    term:
      id: HP:0002140
      label: Ischemic stroke
  evidence:
  - reference: PMID:21050408
    reference_title: "Vertebrobasilar Flow Evaluation and Risk of Transient Ischaemic Attack and Stroke study (VERiTAS): rationale and design."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The patients are prospectively followed for a minimum of one year on current standard medical regimen including vascular risk factor modification, statins and antithrombotic therapy, and evaluated for recurrent ischemic events.
    explanation: This supports vascular risk-factor modification, statins, and antithrombotic therapy as standard medical management in symptomatic vertebrobasilar disease.
  - reference: PMID:35658624
    reference_title: "Treatment of posterior circulation stroke: Acute management and secondary prevention."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Secondary prevention of posterior circulation strokes includes aggressive treatment of cerebrovascular risk factors with both drugs and lifestyle interventions and short-term dual anti-platelet therapy.
    explanation: This supports aggressive medical secondary prevention and short-term dual antiplatelet therapy for posterior-circulation stroke contexts.
- name: Vertebral artery angioplasty and stenting
  description: >-
    Endovascular angioplasty and stenting can restore vertebral artery patency
    in selected symptomatic extracranial vertebral stenosis, especially with
    recurrent symptoms despite medical therapy, but trial evidence has not
    conclusively shown superiority over medical therapy and intracranial
    stenting carries higher procedural risk.
  treatment_term:
    preferred_term: placement of a stent
    term:
      id: NCIT:C71316
      label: Stenting
  target_mechanisms:
  - target: Atherosclerotic vertebral artery stenosis
    treatment_effect: RESTORES
    description: Stenting attempts to restore arterial lumen and improve flow across stenotic vertebral artery segments.
    evidence:
    - reference: PMID:35301953
      reference_title: "Vertebral Artery Interventions: A Comprehensive Updated Review."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        Percutaneous transluminal angioplasty and stenting of symptomatic vertebral artery stenosis are promising options widely used in clinical practice with good technical results; however, the improved clinical outcome has been examined in various clinical trials without a sufficient sample size to conclusively determine whether stenting is better than medical therapy.
      explanation: Supports the intervention acting on the stenosis node with good technical result, while preserving the unresolved outcome question.
  evidence:
  - reference: PMID:35301953
    reference_title: "Vertebral Artery Interventions: A Comprehensive Updated Review."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Percutaneous transluminal angioplasty and stenting of symptomatic vertebral artery stenosis are promising options widely used in clinical practice with good technical results; however, the improved clinical outcome has been examined in various clinical trials without a sufficient sample size to conclusively determine whether stenting is better than medical therapy.
    explanation: This supports clinical use of angioplasty/stenting but preserves uncertainty about outcome superiority over medical therapy.
  - reference: PMID:40951011
    reference_title: "Critical Vertebrobasilar Insufficiency From Left Intracranial Vertebral Artery Stenosis With Contralateral Hypoplasia Presenting as Recurring Vertigo: Urgent Stenting to Prevent the Progression of a Posterior Circulation Stroke."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Given refractory symptoms despite dual antiplatelet therapy and permissive hypertension, urgent intracranial balloon angioplasty and balloon-mounted drug-eluting stent placement was performed.
    explanation: This case report supports stenting as an intervention for refractory vertebrobasilar insufficiency from vertebral artery stenosis, but evidence remains case-level.
- name: Microsurgical vertebral artery revascularization
  description: >-
    Vertebral endarterectomy, artery transposition, hybrid surgery, or related
    microsurgical reconstruction may be considered for selected proximal
    vertebral artery stenosis or occlusion when endovascular treatment is
    unsuitable, fails, or restenosis occurs.
  treatment_term:
    preferred_term: surgical procedure on vascular system
    term:
      id: NCIT:C157725
      label: Vascular Surgical Procedure
  target_mechanisms:
  - target: Atherosclerotic vertebral artery stenosis
    treatment_effect: RESTORES
    description: Microsurgical reconstruction attempts to restore vertebral artery inflow or bypass obstructive anatomy.
    evidence:
    - reference: PMID:39673653
      reference_title: "Application of microsurgical surgery in patients with proximal vertebral artery stenosis unsuited for endovascular treatment: a single-center retrospective study."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        Postoperative imaging examinations in the 34 patients (Males: 79.4%; Mean age: 66.7 ± 9.6 years) revealed patent vertebral and supplying arteries.
      explanation: Post-operative vessel patency is the direct imaging readout that this link's restored-inflow claim asserts.
    - reference: PMID:37483445
      reference_title: "Microsurgical revascularization of a symptomatic proximal vertebral artery: pilot experiences from a single center."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        Microsurgical reconstruction is an alternative option that can effectively treat refractory proximal VASO disease and in-stent stenosis, with a high rate of postoperative vascular recirculation.
      explanation: Restored vascular recirculation is the mechanism by which this intervention acts on vertebral stenosis.
  - target: Atherosclerotic vertebral artery occlusion
    treatment_effect: RESTORES
    description: Selected microsurgical reconstructions can restore vertebral inflow or bypass proximal occlusive anatomy.
    evidence:
    - reference: PMID:37483445
      reference_title: "Microsurgical revascularization of a symptomatic proximal vertebral artery: pilot experiences from a single center."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        Microsurgical reconstruction is an alternative option that can effectively treat refractory proximal VASO disease and in-stent stenosis, with a high rate of postoperative vascular recirculation.
      explanation: The VASO cohort includes proximal vertebral occlusive disease and reports restoration of vascular recirculation after reconstruction.
  evidence:
  - reference: PMID:37483445
    reference_title: "Microsurgical revascularization of a symptomatic proximal vertebral artery: pilot experiences from a single center."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Microsurgical reconstruction is an alternative option that can effectively treat refractory proximal VASO disease and in-stent stenosis, with a high rate of postoperative vascular recirculation.
    explanation: This supports microsurgical reconstruction for refractory proximal vertebral artery stenosis/occlusion and in-stent stenosis.
  - reference: PMID:39673653
    reference_title: "Application of microsurgical surgery in patients with proximal vertebral artery stenosis unsuited for endovascular treatment: a single-center retrospective study."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Microsurgical surgery for patients with proximal vertebral artery stenosis, when endovascular treatment is unsuitable, demonstrates good clinical efficacy and a low incidence of complications, offering a viable surgical treatment option.
    explanation: This supports microsurgical surgery in selected proximal vertebral stenosis patients unsuitable for endovascular treatment.
- name: Acute posterior circulation thrombolysis
  description: >-
    When vertebral artery insufficiency progresses to posterior-circulation
    ischemic stroke, intravenous thrombolysis may be considered according to
    acute stroke eligibility.
  treatment_term:
    preferred_term: Pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
  target_phenotypes:
  - preferred_term: ischemic stroke
    term:
      id: HP:0002140
      label: Ischemic stroke
  evidence:
  - reference: PMID:35658624
    reference_title: "Treatment of posterior circulation stroke: Acute management and secondary prevention."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Thrombolysis seems to have similar benefits and lower hemorrhage risks than in the anterior circulation. The recent ATTENTION and BAOCHE trials have demonstrated that thrombectomy benefits strokes with basilar artery occlusion, but its effect on other posterior occlusion sites remains uncertain.
    explanation: This supports thrombolysis as an acute reperfusion treatment for posterior-circulation stroke.
- name: Basilar artery mechanical thrombectomy
  description: >-
    Mechanical thrombectomy is relevant when posterior-circulation ischemic
    stroke involves basilar artery occlusion, while evidence for other posterior
    occlusion sites remains less certain.
  treatment_term:
    preferred_term: thrombectomy
    term:
      id: NCIT:C52003
      label: Thrombectomy
  target_phenotypes:
  - preferred_term: ischemic stroke
    term:
      id: HP:0002140
      label: Ischemic stroke
  evidence:
  - reference: PMID:35658624
    reference_title: "Treatment of posterior circulation stroke: Acute management and secondary prevention."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Thrombolysis seems to have similar benefits and lower hemorrhage risks than in the anterior circulation. The recent ATTENTION and BAOCHE trials have demonstrated that thrombectomy benefits strokes with basilar artery occlusion, but its effect on other posterior occlusion sites remains uncertain.
    explanation: This supports thrombectomy for basilar artery occlusion while preserving uncertainty for other posterior-circulation occlusion sites.
clinical_trials:
- name: NCT05885932
  phase: NOT_APPLICABLE
  status: RECRUITING
  description: >-
    Randomized multicenter trial of drug-eluting stenting plus best medical
    treatment versus best medical treatment alone for 70-99% extracranial
    vertebral artery stenosis causing recent stroke or TIA.
  target_phenotypes:
  - preferred_term: transient ischemic attack
    term:
      id: HP:0002326
      label: Transient ischemic attack
  - preferred_term: ischemic stroke
    term:
      id: HP:0002140
      label: Ischemic stroke
  evidence:
  - reference: clinicaltrials:NCT05885932
    reference_title: "Drug-eluting Stenting Versus Medical Treatment Alone for Patients With Extracranial Vertebral Artery Stenosis: The VISTA Trial"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Patients will be randomized (1:1) to best medical treatment alone or medical treatment plus stenting.
    explanation: This trial summary directly supports randomized comparison of medical therapy alone versus stenting plus medical therapy.
- name: NCT03201432
  phase: NOT_APPLICABLE
  status: COMPLETED
  description: >-
    Randomized trial comparing drug-eluting stents versus bare metal stents for
    symptomatic extracranial vertebral artery stenosis, focused on restenosis
    prevention after vertebral artery reconstruction.
  target_phenotypes:
  - preferred_term: ischemic stroke
    term:
      id: HP:0002140
      label: Ischemic stroke
  evidence:
  - reference: clinicaltrials:NCT03201432
    reference_title: "A Randomized Trial for Treatment of Symptomatic Extracranial Vertebral Artery Stenosis: Drug Eluting Stents Versus Bare Metal Stents"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Previous systematic review had suggested that the drug eluting stent might reduce the incidence of restenosis of vertebral artery.
    explanation: This trial summary supports evaluation of stent type for restenosis prevention in symptomatic extracranial vertebral artery stenosis.
📚

References & Deep Research

References

14
PMID:35301953
Vertebral Artery Interventions: A Comprehensive Updated Review.
No top-level findings curated for this source.
DOI:10.1111/j.1747-4949.2010.00528.x
Vertebrobasilar Flow Evaluation and Risk of Transient Ischaemic Attack and Stroke Study (Veritas): Rationale and Design
No top-level findings curated for this source.
DOI:10.3389/fneur.2023.1202565
Microsurgical revascularization of a symptomatic proximal vertebral artery: pilot experiences from a single center
No top-level findings curated for this source.
DOI:10.1177/17474930221107500
Treatment of posterior circulation stroke: Acute management and secondary prevention
No top-level findings curated for this source.
DOI:10.1161/str.0000000000000475
2024 Guideline for the Primary Prevention of Stroke: A Guideline From the American Heart Association/American Stroke Association
No top-level findings curated for this source.
DOI:10.1186/s12883-023-03110-z
In-stent restenosis and stented-territory infarction after carotid and vertebrobasilar artery stenting
No top-level findings curated for this source.
DOI:10.1007/s10143-024-03153-x
Application of microsurgical surgery in patients with proximal vertebral artery stenosis unsuited for endovascular treatment: a single-center retrospective study
No top-level findings curated for this source.
DOI:10.1177/21925682231209631
A Systematic Review and Meta-Analysis of Vertebral Artery Injury After Cervical Spine Trauma
No top-level findings curated for this source.
DOI:10.1186/s41983-024-00893-x
Vertebral artery dissection from etiopathogenesis to management therapy: a narrative review with neuroimaging's case illustration
No top-level findings curated for this source.
DOI:10.1161/strokeaha.115.009215
Hemodynamic Features of Symptomatic Vertebrobasilar Disease
No top-level findings curated for this source.
PMID:28680502
Pathophysiology and Diagnosis of Vertebrobasilar Insufficiency: A Review of the Literature.
No top-level findings curated for this source.
PMID:11385214
Accuracy of color-Doppler in the quantification of proximal vertebral artery stenoses.
No top-level findings curated for this source.
PMID:36127977
Vertebral Artery Stenosis: A Narrative Review.
No top-level findings curated for this source.
PMID:12870261
A case of intimal hyperplasia induced by stenting for vertebral artery origin stenosis: assessed on intravascular ultrasound.
No top-level findings curated for this source.

Deep Research

1
Falcon ▸
Disease Characteristics Research Template
Edison Scientific Literature 43 citations 2026-05-06T15:23:52.718460

Question: You are an expert researcher providing comprehensive, well-cited information.

Provide detailed information focusing on: 1. Key concepts and definitions with current understanding 2. Recent developments and latest research (prioritize 2023-2024 sources) 3. Current applications and real-world implementations 4. Expert opinions and analysis from authoritative sources 5. Relevant statistics and data from recent studies

Format as a comprehensive research report with proper citations. Include URLs and publication dates where available. Always prioritize recent, authoritative sources and provide specific citations for all major claims.

Disease Characteristics Research Template

Target Disease

  • Disease Name: Vertebral Artery Insufficiency
  • MONDO ID: (if available)
  • Category: Complex

Research Objectives

Please provide a comprehensive research report on Vertebral Artery Insufficiency covering all of the disease characteristics listed below. This report will be used to populate a disease knowledge base entry. Be thorough and cite primary literature (PMID preferred) for all claims.

For each section, suggested databases/resources are listed. These are the first places you should search for information on each topic.

1. Disease Information

Search first: OMIM, Orphanet, ICD-10/ICD-11, MeSH, PubMed

  • What is the disease? Provide a concise overview.
  • What are the key identifiers? (OMIM, Orphanet, ICD-10/ICD-11, MeSH, Mondo)
  • What are the common synonyms and alternative names?
  • Is the information derived from individual patients (e.g., EHR) or aggregated disease-level resources?

2. Etiology

  • Disease Causal Factors: What are the primary causes? (genetic, environmental, infectious, mechanistic)
  • Risk Factors:

    Search first: PubMed, Cochrane Library, UpToDate, clinical guidelines, ClinVar, ClinGen, GWAS Catalog, PheGenI, CTD, CDC, WHO, epidemiological databases

  • Genetic risk factors (causal variants, susceptibility loci, modifier genes)
  • Environmental risk factors (toxins, lifestyle, occupational exposures, age, sex, family history)
  • Protective Factors:

    Search first: PubMed, Cochrane Library, clinical trial databases, GWAS Catalog, gnomAD, WHO, CDC, nutrition databases

  • Genetic protective factors (protective variants, modifier alleles)
  • Environmental protective factors (diet, lifestyle, exposures that reduce risk)
  • Gene-Environment Interactions: How do genetic and environmental factors interact to influence disease?

    Search first: CTD, PubMed, PheGenI, GxE databases

3. Phenotypes

Search first: HPO (Human Phenotype Ontology), OMIM, Orphanet, PubMed, clinicaltrials.gov, MedDRA, SNOMED CT, DECIPHER, LOINC

For each phenotype, provide: - Phenotype type: symptoms, clinical signs, physical manifestations, behavioral changes, or laboratory abnormalities

For symptoms/signs: HPO, OMIM, Orphanet, PubMed For behavioral changes: HPO, DSM, RDoC (Research Domain Criteria), PubMed For laboratory abnormalities: LOINC, SNOMED CT, LabTests Online, PubMed - Phenotype characteristics: Search first: OMIM, Orphanet, HPO, PubMed - Age of symptom onset (neonatal, childhood, adult-onset, late-onset) - Symptom severity (mild, moderate, severe, variable) - Symptom progression (stable, progressive, episodic, fluctuating) - Frequency among affected individuals (percentage or qualitative) - Quality of life impact: Effects on daily functioning and well-being (per-phenotype when possible) Search first: EQ-5D database, SF-36, WHO QOL databases, PubMed - Suggest HPO (Human Phenotype Ontology) terms for each phenotype

4. Genetic/Molecular Information

  • Causal Genes: Gene mutations or chromosomal abnormalities responsible for disease (gene symbols, OMIM IDs)

    Search first: OMIM, ClinVar, HGMD, Ensembl, NCBI Gene

  • Pathogenic Variants:
  • Affected genes (gene symbols, HGNC IDs) > Search first: OMIM, NCBI Gene, Ensembl, HGNC, UniProt, GeneCards
  • Variant classification (pathogenic, likely pathogenic, VUS per ACMG/AMP guidelines) > Search first: ClinVar, ClinGen, ACMG/AMP guidelines, VarSome
  • Variant type/class (missense, frameshift, nonsense, splice-site, structural)
  • Allele frequency in population databases > Search first: gnomAD, 1000 Genomes, ExAC, TOPMed, dbSNP
  • Somatic vs germline origin > Search first: COSMIC (somatic), ClinVar, ICGC, TCGA
  • Functional consequences (loss of function, gain of function, dominant negative)
  • Modifier Genes: Genes that modify disease severity or expression
  • Epigenetic Information: DNA methylation, histone modifications, chromatin changes affecting disease

    Search first: ENCODE, Roadmap Epigenomics, MethBase, DiseaseMeth

  • Chromosomal Abnormalities: Large-scale genetic changes (aneuploidy, translocations, inversions)

    Search first: DECIPHER, ClinVar, ECARUCA, UCSC Genome Browser

5. Environmental Information

  • Environmental Factors: Non-genetic contributing factors (toxins, radiation, pollution, occupational exposure)

    Search first: CTD (Comparative Toxicogenomics Database), TOXNET, PubMed, EPA databases

  • Lifestyle Factors: Behavioral factors (smoking, diet, exercise, alcohol consumption)

    Search first: CDC databases, WHO, PubMed, NHANES

  • Infectious Agents: If applicable, pathogens causing or triggering disease (bacteria, viruses, fungi, parasites)

    Search first: NCBI Taxonomy, ViPR, BV-BRC, MicrobeDB, GIDEON

6. Mechanism / Pathophysiology

  • Molecular Pathways: Specific signaling cascades or biochemical pathways involved (Wnt, MAPK, mTOR, PI3K-AKT, etc.)

    Search first: KEGG, Reactome, WikiPathways, PathBank, BioCyc

  • Cellular Processes: Cell-level mechanisms (apoptosis, autophagy, cell cycle dysregulation, inflammation, etc.)

    Search first: Gene Ontology (GO), Reactome, KEGG, PubMed

  • Protein Dysfunction: How protein structure or function is altered (misfolding, aggregation, loss of function, gain of function)

    Search first: UniProt, PDB (Protein Data Bank), InterPro, Pfam, AlphaFold

  • Metabolic Changes: Alterations in metabolic processes (energy metabolism, lipid metabolism, amino acid metabolism)

    Search first: KEGG, BioCyc, HMDB (Human Metabolome Database), BRENDA

  • Immune System Involvement: Role of immune response (autoimmunity, immunodeficiency, chronic inflammation)

    Search first: ImmPort, Immunome Database, IEDB, Gene Ontology

  • Tissue Damage Mechanisms: How tissues/ are injured (oxidative stress, ischemia, fibrosis, necrosis)

    Search first: PubMed, Gene Ontology, Reactome

  • Biochemical Abnormalities: Specific molecular defects (enzyme deficiencies, receptor dysfunction, ion channel defects)

    Search first: BRENDA, UniProt, KEGG, OMIM, PubMed

  • Epigenetic Changes: DNA methylation, histone modifications affecting gene expression in disease

    Search first: ENCODE, Roadmap Epigenomics, MethBase, DiseaseMeth

  • Molecular Profiling (if available):
  • Transcriptomics/gene expression changes > Search first: GEO (Gene Expression Omnibus), ArrayExpress, GTEx, Human Cell Atlas, SRA
  • Proteomics findings > Search first: PRIDE, ProteomeXchange, Human Protein Atlas, STRING, BioGRID
  • Metabolomics signatures > Search first: MetaboLights, Metabolomics Workbench, HMDB, METLIN
  • Lipidomics alterations > Search first: LIPID MAPS, SwissLipids, LipidHome, Metabolomics Workbench
  • Genomic structural features > Search first: UCSC Genome Browser, Ensembl, NCBI, dbVar, DGV
  • Advanced Technologies (if applicable):
  • Single-cell analysis findings (cell-type specific mechanisms, cellular heterogeneity) > Search first: Human Cell Atlas, Single Cell Portal, GEO, CELLxGENE
  • Spatial transcriptomics findings > Search first: GEO, Spatial Research, Vizgen, 10x Genomics data
  • Multi-omics integration results > Search first: TCGA, ICGC, cBioPortal, LinkedOmics, PubMed
  • Functional genomics screens (CRISPR, RNAi) > Search first: DepMap, GenomeRNAi, PubMed, BioGRID ORCS

For each mechanism, describe: - The causal chain from initial trigger to clinical manifestation - Which mechanisms are upstream vs downstream - What cell types and biological processes are involved - Suggest GO terms for biological processes and CL terms for cell types

7. Anatomical Structures Affected

  • Organ Level:
  • Primary organs directly affected
  • Secondary organ involvement (complications, secondary effects)
  • Body systems involved (cardiovascular, nervous, digestive, respiratory, endocrine, etc.)

    Search first: Uberon, FMA (Foundational Model of Anatomy), OMIM, HPO, ICD-11, MeSH, SNOMED CT

  • Tissue and Cell Level:
  • Specific tissue types affected (epithelial, connective, muscle, nervous)
  • Specific cell populations targeted (with Cell Ontology terms)

    Search first: Uberon, Human Protein Atlas, Cell Ontology, Human Cell Atlas, CellMarker, PanglaoDB

  • Subcellular Level:
  • Cellular compartments involved (mitochondria, nucleus, ER, lysosomes) (with GO Cellular Component terms)

    Search first: Gene Ontology (Cellular Component), UniProt, Human Protein Atlas

  • Localization:
  • Specific anatomical sites (with UBERON terms) > Search first: FMA, Uberon, NeuroNames (for brain), SNOMED CT
  • Lateralization (unilateral, bilateral, asymmetric) > Search first: HPO, clinical literature, imaging databases

8. Temporal Development

  • Onset:
  • Typical age of onset (congenital, pediatric, adult, geriatric)
  • Onset pattern (acute, subacute, chronic, insidious)

    Search first: OMIM, Orphanet, HPO, PubMed

  • Progression:
  • Disease stages (early, intermediate, advanced, end-stage) > Search first: Cancer Staging Manual (AJCC), WHO classifications, PubMed
  • Progression rate (rapid, slow, variable)
  • Disease course pattern (episodic, relapsing-remitting, progressive, stable)
  • Disease duration (self-limited, chronic lifelong)

    Search first: Disease registries, longitudinal cohort databases, natural history studies, PubMed, Orphanet, OMIM

  • Patterns:
  • Remission patterns (spontaneous, treatment-induced) > Search first: Clinical trial databases, disease registries, PubMed
  • Critical periods (time windows of vulnerability or opportunity for intervention) > Search first: PubMed, developmental biology databases, clinical guidelines

9. Inheritance and Population

  • Epidemiology:
  • Prevalence (cases per 100,000 at given time)
  • Incidence (new cases per 100,000 per year)

    Search first: Orphanet, CDC, WHO, GBD (Global Burden of Disease), national registries, SEER, disease registries

  • For Genetic Etiology:
  • Inheritance pattern (AD, AR, X-linked, mitochondrial, multifactorial, polygenic) > Search first: OMIM, Orphanet, ClinVar, GTR (Genetic Testing Registry)
  • Penetrance (complete, incomplete, age-dependent) > Search first: ClinVar, OMIM, PubMed, ClinGen
  • Expressivity (variable, consistent) > Search first: OMIM, ClinVar, PubMed
  • Genetic anticipation (increasing severity in successive generations) > Search first: OMIM, PubMed (especially for repeat expansion disorders)
  • Germline mosaicism > Search first: ClinVar, OMIM, genetic counseling literature, PubMed
  • Founder effects (population-specific mutations) > Search first: gnomAD, population genetics databases, PubMed
  • Consanguinity role > Search first: OMIM, population studies, genetic counseling resources
  • Carrier frequency > Search first: gnomAD, carrier screening databases, GeneReviews, GTR
  • Population Demographics:
  • Affected populations (ethnic or demographic groups with higher prevalence) > Search first: gnomAD, 1000 Genomes, PAGE Study, PubMed, population registries
  • Geographic distribution (endemic areas, regional variation) > Search first: WHO, CDC, GBD, Orphanet, geographic epidemiology databases
  • Geographic distribution of specific variants
  • Sex ratio (male:female) > Search first: Disease registries, OMIM, PubMed, epidemiological databases
  • Age distribution of affected individuals > Search first: CDC, disease registries, SEER, Orphanet

10. Diagnostics

  • Clinical Tests:
  • Laboratory tests (blood, urine, tissue chemistry, specific enzyme assays) > Search first: LOINC, LabTests Online, PubMed
  • Biomarkers (proteins, metabolites, genetic markers, circulating biomarkers) > Search first: FDA Biomarker List, BEST (Biomarkers, EndpointS, and other Tools), PubMed
  • Imaging studies (X-ray, CT, MRI, PET, ultrasound) > Search first: RadLex, DICOM, Radiopaedia, imaging databases
  • Functional tests (pulmonary function, cardiac stress tests) > Search first: LOINC, clinical guidelines, PubMed
  • Electrophysiology (EEG, EMG, ECG, nerve conduction studies) > Search first: LOINC, clinical neurophysiology databases, PubMed
  • Biopsy findings (histopathology, immunohistochemistry) > Search first: SNOMED CT, College of American Pathologists resources, PubMed
  • Pathology findings (microscopic examination) > Search first: SNOMED CT, Digital Pathology databases, PubMed
  • Genetic Testing:

    Search first: GTR (Genetic Testing Registry), GeneReviews, ClinGen

  • Overview of recommended genetic testing approach
  • Whole genome sequencing (WGS) utility > Search first: GTR, ClinVar, GEL (Genomics England), gnomAD
  • Whole exome sequencing (WES) utility > Search first: GTR, ClinVar, OMIM, GeneMatcher
  • Gene panels (which panels, which genes) > Search first: GTR, ClinVar, laboratory-specific databases
  • Single gene testing > Search first: GTR, ClinVar, OMIM, GeneReviews
  • Chromosomal microarray (CMA) > Search first: DECIPHER, ClinVar, dbVar, ECARUCA
  • Karyotyping > Search first: Chromosome Abnormality Database, ClinVar, cytogenetics resources
  • FISH > Search first: ClinVar, cytogenetics databases, PubMed
  • Mitochondrial DNA testing > Search first: MITOMAP, MSeqDR, ClinVar, GTR
  • Repeat expansion testing > Search first: GTR, ClinVar, repeat expansion databases, PubMed
  • Omics-Based Diagnostics (if applicable):
  • RNA sequencing / transcriptomics > Search first: GEO, ArrayExpress, GTEx, RNA-seq databases
  • Proteomics > Search first: PRIDE, ProteomeXchange, FDA Biomarker database
  • Metabolomics > Search first: MetaboLights, Metabolomics Workbench, HMDB
  • Epigenomics > Search first: GEO, ENCODE, Roadmap Epigenomics, MethBase
  • Liquid biopsy > Search first: COSMIC, ClinVar, liquid biopsy databases, PubMed
  • Clinical Criteria:
  • Standardized diagnostic criteria (DSM, ICD, society guidelines) > Search first: DSM-5, ICD-11, clinical society guidelines, UpToDate
  • Differential diagnosis (other conditions to rule out, with distinguishing features) > Search first: DynaMed, UpToDate, clinical decision support systems
  • Screening:
  • Screening methods for asymptomatic individuals (newborn screening, carrier screening, cascade screening) > Search first: ACMG recommendations, CDC newborn screening, GTR

11. Outcome/Prognosis

  • Survival and Mortality:
  • Survival rate (5-year, 10-year, overall) > Search first: SEER, cancer registries, disease-specific registries, PubMed
  • Life expectancy (with and without treatment if applicable) > Search first: Orphanet, disease registries, actuarial databases, PubMed
  • Mortality rate > Search first: CDC, WHO, GBD, national mortality databases
  • Disease-specific mortality (deaths directly attributable to disease) > Search first: Disease registries, CDC Wonder, GBD, PubMed
  • Morbidity and Function:
  • Morbidity (disease-related disability and health impacts) > Search first: GBD, WHO, disability databases, PubMed
  • Disability outcomes (long-term functional impairments) > Search first: ICF (International Classification of Functioning), disability registries
  • Quality of life measures (EQ-5D, SF-36, PROMIS, disease-specific tools) > Search first: EQ-5D database, SF-36, PROMIS, PubMed
  • Disease Course:
  • Complications (secondary problems: infections, organ failure, etc.) > Search first: ICD codes, disease registries, clinical databases, PubMed
  • Recovery potential (likelihood and extent of recovery, with vs without treatment) > Search first: Natural history studies, rehabilitation databases, PubMed
  • Prediction:
  • Prognostic factors (age, disease severity, biomarkers, treatment response) > Search first: Prognostic models databases, clinical calculators, PubMed
  • Prognostic biomarkers (molecular markers predicting disease course) > Search first: FDA Biomarker database, PubMed, cancer prognostic databases

12. Treatment

  • Pharmacotherapy:
  • Pharmacological treatments (drug names, drug classes, mechanisms of action) > Search first: DrugBank, RxNorm, ATC classification, DailyMed, FDA databases
  • Pharmacogenomics (how genetic variants affect drug metabolism, efficacy, toxicity) > Search first: PharmGKB, CPIC (Clinical Pharmacogenetics), FDA Table of PGx Biomarkers
  • Advanced Therapeutics:
  • Gene therapy (viral vectors, CRISPR, gene replacement, gene editing) > Search first: ClinicalTrials.gov, FDA gene therapy database, ASGCT resources
  • Cell therapy (stem cell transplant, CAR-T, cellular therapeutics) > Search first: ClinicalTrials.gov, FDA cell therapy database, FACT standards
  • RNA-based therapies (ASOs, siRNA, mRNA therapies) > Search first: ClinicalTrials.gov, FDA approvals, PubMed
  • Targeted therapies (treatments directed at specific molecular targets) > Search first: My Cancer Genome, OncoKB, ClinicalTrials.gov, FDA approvals
  • Immunotherapies (checkpoint inhibitors, monoclonal antibodies) > Search first: Cancer Immunotherapy Database, FDA approvals, ClinicalTrials.gov
  • Surgical and Interventional:
  • Surgical interventions (types of surgery, timing, outcomes) > Search first: CPT codes, surgical registries, clinical guidelines, PubMed
  • Supportive and Rehabilitative:
  • Supportive care (symptom management, pain control, nutrition) > Search first: Clinical guidelines, Cochrane Library, PubMed
  • Rehabilitation (physical therapy, occupational therapy, speech therapy) > Search first: Rehabilitation medicine databases, clinical guidelines, PubMed
  • Experimental:
  • Experimental treatments in clinical trials (with NCT identifiers if available) > Search first: ClinicalTrials.gov, EU Clinical Trials Register, WHO ICTRP
  • Treatment Outcomes:
  • Treatment response rates > Search first: Clinical trial databases, FDA reviews, systematic reviews, PubMed
  • Side effects and adverse events > Search first: FDA Adverse Event Reporting System (FAERS), MedWatch, PubMed
  • Treatment Strategy:
  • Treatment algorithms (clinical pathways, decision trees) > Search first: Clinical practice guidelines, NCCN Guidelines, UpToDate
  • Combination therapies > Search first: ClinicalTrials.gov, treatment guidelines, PubMed
  • Personalized medicine approaches (genotype-guided treatment) > Search first: My Cancer Genome, CIViC, PharmGKB, precision medicine databases

For each treatment, suggest MAXO (Medical Action Ontology) terms where applicable.

13. Prevention

  • Prevention Levels:
  • Primary prevention (preventing disease occurrence: vaccination, risk factor modification) > Search first: CDC, WHO, USPSTF recommendations, Cochrane Library
  • Secondary prevention (early detection and treatment: screening programs, early intervention) > Search first: USPSTF, CDC screening guidelines, WHO
  • Tertiary prevention (preventing complications in those with disease) > Search first: Clinical guidelines, disease management protocols, PubMed
  • Immunization: Vaccine strategies (if applicable)

    Search first: CDC vaccine schedules, WHO immunization, FDA vaccine database

  • Screening and Early Detection:
  • Screening programs (population-based: newborn screening, cancer screening) > Search first: CDC screening programs, USPSTF, cancer screening databases
  • Genetic screening (carrier screening, preimplantation genetic diagnosis, prenatal testing) > Search first: ACMG recommendations, ACOG guidelines, GTR
  • Risk stratification (identifying high-risk individuals for targeted prevention) > Search first: Risk prediction models, clinical calculators, PubMed
  • Behavioral Interventions: Lifestyle modifications to reduce risk

    Search first: CDC, WHO, behavioral intervention databases, Cochrane Library

  • Counseling: Genetic counseling (risk assessment, family planning guidance)

    Search first: NSGC resources, ACMG guidelines, GeneReviews

  • Public Health:
  • Public health interventions (sanitation, vector control, health education) > Search first: CDC, WHO, public health databases, PubMed
  • Environmental interventions (reducing environmental risk factors) > Search first: EPA databases, WHO environmental health, PubMed
  • Prophylaxis: Preventive medications or procedures

    Search first: Clinical guidelines, FDA approvals, PubMed

14. Other Species / Natural Disease

  • Taxonomy: Species affected (with NCBI Taxon identifiers)

    Search first: NCBI Taxonomy

  • Breed: Specific breeds affected (with VBO identifiers if applicable)

    Search first: VBO (Vertebrate Breed Ontology)

  • Gene: Orthologous genes in other species (with NCBI Gene IDs)

    Search first: NCBI Gene

  • Natural Disease:
  • Naturally occurring disease in other species (companion animals, wildlife) > Search first: OMIA (Online Mendelian Inheritance in Animals), VetCompass, PubMed
  • Veterinary relevance and importance in animal health > Search first: OMIA, veterinary databases, PubMed
  • Comparative Biology:
  • Comparative pathology (similarities and differences across species) > Search first: OMIA, comparative pathology databases, PubMed
  • Evolutionary conservation of disease mechanisms > Search first: HomoloGene, OrthoMCL, Alliance of Genome Resources
  • Transmission (if applicable):
  • Zoonotic potential > Search first: CDC zoonotic diseases, WHO zoonoses, GIDEON
  • Cross-species susceptibility > Search first: NCBI Taxonomy, veterinary databases, PubMed

15. Model Organisms

  • Model Types:
  • Model organism type (mammalian, invertebrate, cellular, in vitro) > Search first: Alliance of Genome Resources, model organism databases
  • Specific model systems (mouse, rat, zebrafish, Drosophila, C. elegans, yeast, cell lines, organoids, iPSCs) > Search first: MGI, RGD, ZFIN, FlyBase, WormBase, SGD, ATCC, Cellosaurus
  • Induced models (drug treatment, surgical intervention, environmental manipulation) > Search first: MGI, model organism databases, PubMed
  • Genetic Models:
  • Types available (knockout, knock-in, transgenic, conditional, humanized) > Search first: MGI, IMPC, KOMP, EuMMCR, IMSR
  • Model Characteristics:
  • Phenotype recapitulation (how well model reproduces human disease features) > Search first: Model organism databases, comparative studies, PubMed
  • Model limitations (aspects of human disease not captured) > Search first: Model organism databases, PubMed, review articles
  • Applications:
  • Research applications (what aspects of disease can be studied) > Search first: Model organism databases, PubMed
  • Resources:
  • Model databases > Search first: MGI, RGD, ZFIN, FlyBase, WormBase, IMSR, EMMA, MMRRC

Citation Requirements

  • Cite primary literature (PMID preferred) for all mechanistic and clinical claims
  • Prioritize recent reviews and landmark papers
  • Include direct quotes from abstracts where possible to support key statements
  • Distinguish evidence source types: human clinical, model organism, in vitro, computational

Output Format

Structure your response as a comprehensive narrative organized by the sections above. For each section, provide: - Factual content with specific details (numbers, percentages, gene names, variant nomenclature) - Ontology term suggestions (HPO, GO, CL, UBERON, CHEBI, MAXO, MONDO) where applicable - Evidence citations with PMIDs - Direct quotes from abstracts to support key claims - Clear indication when information is not available or not applicable for this disease

This report will be used to populate a disease knowledge base entry with: - Pathophysiology descriptions with causal chains - Gene/protein annotations (HGNC, GO terms) - Phenotype associations (HP terms) with frequencies - Cell type involvement (CL terms) - Anatomical locations (UBERON terms) - Chemical entities (CHEBI terms) - Treatment annotations (MAXO terms) - Evidence items with PMIDs and exact abstract quotes - Epidemiology, prognosis, diagnostic, and prevention information - Animal model descriptions with phenotype recapitulation details

Comprehensive Research Report: Vertebral Artery Insufficiency (VAI) / Vertebrobasilar Insufficiency (VBI)

Executive summary (current understanding)

Vertebral artery insufficiency (often discussed clinically as vertebrobasilar insufficiency, vertebrobasilar disease, or symptomatic vertebral artery stenosis/occlusion) refers to transient ischemic attacks (TIA) or ischemic strokes attributable to pathology of the vertebral arteries and/or basilar artery, most commonly atherosclerotic stenosis/occlusion, but also dissection/trauma or other less common causes. These conditions contribute substantially to posterior-circulation ischemia and carry high early recurrence risk under medical therapy alone, motivating aggressive secondary prevention and selective revascularization in refractory cases. (bobmanuel2023vertebralarteryinterventions pages 1-2, aminhanjani2010vertebrobasilarflowevaluation pages 1-2)

1. Disease information

1.1 What is the disease?

In contemporary cerebrovascular literature, “vertebral artery insufficiency” is not consistently treated as a single discrete nosologic entity; rather it is typically operationalized as symptomatic posterior circulation ischemia due to vertebral artery (extracranial or intracranial) stenosis/occlusion and/or broader atherosclerotic vertebrobasilar disease. The VERiTAS study frames the clinical problem as symptomatic atherosclerotic vertebrobasilar disease causing posterior circulation stroke, emphasizing that recurrence risk is high and that hemodynamic compromise is a key determinant of risk. (aminhanjani2010vertebrobasilarflowevaluation pages 1-2)

A 2023 comprehensive review similarly uses overlapping terminology (VAS, vertebrobasilar ischemia/insufficiency) and describes vertebral artery stenosis as a driver of posterior circulation ischemia that may be asymptomatic or symptomatic. (bobmanuel2023vertebralarteryinterventions pages 4-5, bobmanuel2023vertebralarteryinterventions pages 2-3)

1.2 Key identifiers (OMIM/Orphanet/ICD/MeSH/MONDO)

Not available from the retrieved evidence set. The sourced papers and guideline excerpts used here do not provide definitive ICD-10/ICD-11, MeSH, OMIM, Orphanet, or MONDO identifiers specific to “vertebral artery insufficiency/vertebrobasilar insufficiency.” This report therefore focuses on evidence-based clinical characterization and management rather than coding/ontology assertions.

1.3 Synonyms and alternative names

Commonly used overlapping terms in the literature include: - Vertebrobasilar insufficiency (VBI) / vertebrobasilar ischemia (bobmanuel2023vertebralarteryinterventions pages 4-5, bobmanuel2023vertebralarteryinterventions pages 3-4) - Atherosclerotic vertebrobasilar disease (VBD) (aminhanjani2010vertebrobasilarflowevaluation pages 1-2) - Vertebral artery stenosis (VAS) / vertebral artery stenosis and occlusion (VASO) (zhang2023microsurgicalrevascularizationof pages 1-2) - Posterior circulation ischemia / posterior circulation stroke (markus2022treatmentofposterior pages 1-2)

1.4 Evidence source type

The information below is derived from aggregated disease-level evidence, including: - Peer-reviewed reviews and guideline documents (bobmanuel2023vertebralarteryinterventions pages 4-5, markus2022treatmentofposterior pages 1-2, bushnell20242024guidelinefor pages 25-26) - Prospective observational studies (VERiTAS rationale and analyses) (aminhanjani2010vertebrobasilarflowevaluation pages 1-2) - Retrospective real-world surgical/endovascular cohorts (ryu2023instentrestenosisand pages 2-4, liu2024applicationofmicrosurgical pages 1-2) - Systematic reviews/meta-analyses for traumatic vertebral artery injury (goyal2024asystematicreview pages 1-2)

2. Etiology

2.1 Disease causal factors

Primary causal substrate in typical VAI/VBI presentations: - Atherosclerotic stenosis/occlusion of vertebral artery segments (notably ostium/proximal segments) is described as the major mechanism in reviews. (bobmanuel2023vertebralarteryinterventions pages 1-2, bobmanuel2023vertebralarteryinterventions pages 2-3)

Other causes (less common, but clinically important): - Dissection (spontaneous or traumatic) (bobmanuel2023vertebralarteryinterventions pages 3-4, amran2024vertebralarterydissection pages 1-2) - Trauma-related vertebral artery injury (TVAI) after cervical spine trauma (goyal2024asystematicreview pages 1-2) - Congenital anomalies including vertebral artery hypoplasia/atresia (bobmanuel2023vertebralarteryinterventions pages 3-4) - Extrinsic compression and vasculitis (mentioned as less common causes) (bobmanuel2023vertebralarteryinterventions pages 2-3)

2.2 Risk factors

Atherosclerotic disease risk factors (vascular risk factor paradigm): AHA/ASA-aligned medical therapy guidance in vertebral artery disease emphasizes standard vascular risk factor modification (blood pressure management, diabetes control, smoking cessation) and intensive medical therapy for secondary prevention. (bobmanuel2023vertebralarteryinterventions pages 4-5)

Anatomic/structural risk factors: - Vertebral artery hypoplasia reported frequency 2–6% (autopsy/angiogram), and is noted as associated with symptomatic vertebrobasilar occlusive disease. (bobmanuel2023vertebralarteryinterventions pages 3-4)

Trauma-related risk factors (for traumatic VAI): - In cervical spine trauma, vertebral artery injury is associated with high-risk fracture patterns; evaluation uses modified Denver screening criteria in trauma literature and CTA-based screening. (goyal2024asystematicreview pages 1-2)

2.3 Protective factors

No specific protective genetic variants or protective environmental exposures were identified in the retrieved sources.

2.4 Gene–environment interactions

Not specifically addressed in the retrieved evidence set.

3. Phenotypes

3.1 Symptom and sign spectrum (with suggested HPO terms)

VAI/VBI phenotypes reflect the affected posterior circulation territory (brainstem, cerebellum, thalamus, occipital cortex, vestibular pathways). (bobmanuel2023vertebralarteryinterventions pages 3-4)

Common posterior circulation TIA/stroke symptom clusters used in VERiTAS baseline characterization include: - “Loss of balance, vertigo, unsteadiness or disequilibrium, diplopia, dysphagia, or dysarthria.” (aminhanjani2015hemodynamicfeaturesof pages 7-10) - Motor dysfunction (“weakness, paralysis, or clumsiness”) and sensory symptoms (“numbness, or paresthesia”). (aminhanjani2015hemodynamicfeaturesof pages 7-10) - Homonymous visual field loss. (aminhanjani2015hemodynamicfeaturesof pages 7-10)

Syndromic localization examples (review-level descriptions): - Intracranial vertebral occlusion → lateral medullary (Wallenberg) syndrome with “Horner’s syndrome, dysphagia, hoarse voice, limb ataxia, and decreased pain/ temperature sensation of the ipsilateral face and contralateral body.” (bobmanuel2023vertebralarteryinterventions pages 3-4) - Basilar artery occlusion → “Locked-In-Syndrome (the patient becomes quadriplegic and mute, but remains conscious)” (bobmanuel2023vertebralarteryinterventions pages 3-4) - Distal basilar occlusion prodrome: “vertigo, nausea, headache, neck pain, and transient lateralized motor weakness.” (bobmanuel2023vertebralarteryinterventions pages 3-4)

Vertebral artery dissection (VAD) phenotypes (2024 review): - “The most frequent clinical manifestations include stroke, transient ischemic attack, neck pain, headaches, and vertigo.” (amran2024vertebralarterydissection pages 1-2)

Suggested HPO mappings (non-exhaustive): - Vertigo: HP:0002321 (bobmanuel2023vertebralarteryinterventions pages 3-4, amran2024vertebralarterydissection pages 1-2, aminhanjani2015hemodynamicfeaturesof pages 7-10) - Ataxia / limb ataxia: HP:0001251 (bobmanuel2023vertebralarteryinterventions pages 3-4) - Dysphagia: HP:0002015 (bobmanuel2023vertebralarteryinterventions pages 3-4, aminhanjani2015hemodynamicfeaturesof pages 7-10) - Dysarthria: HP:0001260 (aminhanjani2015hemodynamicfeaturesof pages 7-10) - Diplopia: HP:0000651 (aminhanjani2015hemodynamicfeaturesof pages 7-10) - Visual field defect (homonymous hemianopia): HP:0000581 (aminhanjani2015hemodynamicfeaturesof pages 7-10) - Headache: HP:0002315 (bobmanuel2023vertebralarteryinterventions pages 3-4, amran2024vertebralarterydissection pages 1-2) - Neck pain: HP:0003302 (bobmanuel2023vertebralarteryinterventions pages 3-4, amran2024vertebralarterydissection pages 1-2) - Horner syndrome: HP:0000009 (bobmanuel2023vertebralarteryinterventions pages 3-4)

3.2 Phenotype characteristics and frequency data

Posterior circulation syndrome distribution in VERiTAS (selected): Among symptomatic vertebrobasilar disease patients, “Pontine syndrome” was common (e.g., 59% in basilar-only disease; 23% vertebral-only; 48% combined basilar+vertebral), while “Pure cerebellar” syndromes occurred at ~14–23% across groups. (aminhanjani2015hemodynamicfeaturesof pages 10-15)

Quality of life impact Not directly quantified with standardized QoL instruments (e.g., EQ-5D, PROMIS) in the retrieved sources; however, posterior circulation ischemic events are recognized to be disabling and associated with substantial morbidity/mortality, particularly for basilar occlusion and recurrent events. (zhang2023microsurgicalrevascularizationof pages 1-2, markus2022treatmentofposterior pages 3-4)

4. Genetic / molecular information

4.1 Causal genes and pathogenic variants

Typical atherosclerotic VAI/VBI: No monogenic causal genes/variants were identified in the retrieved sources.

Dissection-associated VAI: A 2024 VAD review lists “connective tissue disorders” as intrinsic contributors and states “Predisposing factors include connective tissue disorders… and the presence of infection or inflammation,” and later mentions “connective tissue diseases… and elastin insufficiency.” However, no named hereditary syndromes (e.g., Ehlers–Danlos, Marfan) or specific genes/variants were provided in the retrieved excerpts. (amran2024vertebralarterydissection pages 1-2, amran2024vertebralarterydissection pages 6-8)

4.2 Modifier genes / epigenetics / chromosomal abnormalities

Not addressed in the retrieved evidence set.

5. Environmental information

5.1 Environmental/lifestyle contributors

For typical atherosclerotic vertebrobasilar disease, the key modifiable contributors are the standard vascular risk factors targeted by guideline-based prevention: blood pressure control, diabetes management, smoking cessation, lipid management, and lifestyle interventions. (bobmanuel2023vertebralarteryinterventions pages 4-5, markus2022treatmentofposterior pages 4-5)

5.2 Infectious agents

Not established as direct causes in the retrieved sources; infection/inflammation is mentioned only as a predisposing factor context for dissection. (amran2024vertebralarterydissection pages 1-2)

6. Mechanism / pathophysiology

6.1 Causal chain (from trigger to manifestations)

Atherosclerotic vertebrobasilar disease: 1) Atherosclerotic plaque/stenosis in vertebral/basilar arteries (often proximal/ostial vertebral artery) (bobmanuel2023vertebralarteryinterventions pages 1-2) 2) Reduced perfusion pressure and/or plaque-related thromboembolism (aminhanjani2010vertebrobasilarflowevaluation pages 1-2) 3) Distal territory hypoperfusion and/or embolic infarction in brainstem/cerebellum/occipital territories, yielding symptoms such as vertigo, ataxia, diplopia, dysarthria, dysphagia, and focal weakness/sensory loss. (aminhanjani2015hemodynamicfeaturesof pages 7-10, bobmanuel2023vertebralarteryinterventions pages 3-4)

Hemodynamic compromise as an upstream driver of risk: The VERiTAS rationale highlights that posterior circulation stroke risk is strongly related to hemodynamic compromise and that this can be measured noninvasively with quantitative MRA. (aminhanjani2010vertebrobasilarflowevaluation pages 1-2)

Mechanism heterogeneity (hemodynamic vs embolic): Infarct-pattern analyses within the VERiTAS cohort describe both hemodynamic and embolic/perforator-related patterns, implying mixed downstream mechanisms even in the same etiologic category. (aminhanjani2010vertebrobasilarflowevaluation pages 1-2)

6.2 Suggested GO biological process terms (hypothesis-driven)

Not directly measured in the retrieved evidence set; plausible GO terms for the biological processes involved include: - GO:0001525 angiogenesis (collateral adaptation context) - GO:0007596 blood coagulation / GO:0030193 regulation of blood coagulation (thromboembolism) - GO:0006928 movement of cell or subcellular component (platelet activation/aggregation context)

These are proposed mappings; no direct molecular profiling evidence was retrieved.

6.3 Suggested Cell Ontology (CL) terms

Primary implicated cell types (conceptual, not directly profiled in retrieved evidence): - Endothelial cell (CL:0000115) - Vascular smooth muscle cell (CL:0000192) - Platelet (CL:0000233)

7. Anatomical structures affected

7.1 Organ/system level

  • Cardiovascular system / cerebrovascular arterial system: vertebral arteries and basilar artery (aminhanjani2010vertebrobasilarflowevaluation pages 1-2)
  • Central nervous system: posterior circulation territories including brainstem, cerebellum, thalamus, occipital cortex (bobmanuel2023vertebralarteryinterventions pages 3-4)

7.2 Suggested UBERON terms (examples)

  • Vertebral artery: UBERON:0001643
  • Basilar artery: UBERON:0001642
  • Brainstem: UBERON:0002298
  • Cerebellum: UBERON:0002037
  • Occipital lobe (visual cortex region): UBERON:0001871

(UBERON IDs provided as standard anatomy mappings; not explicitly enumerated in retrieved texts.)

8. Temporal development

8.1 Onset patterns

  • Atherosclerotic VAI/VBI typically presents in older adults (implied by atherosclerotic risk factor management paradigms and interventional cohorts) and can present as TIA or stroke. (bobmanuel2023vertebralarteryinterventions pages 4-5, liu2024applicationofmicrosurgical pages 1-2)
  • Vertebral artery dissection is highlighted as a cause of stroke/TIA in younger adults; one review states it “usually occurs at an average age of 46.5 years.” (amran2024vertebralarterydissection pages 1-2)

8.2 Progression

Early recurrence risk is emphasized: in medically treated symptomatic vertebrobasilar disease, recurrence is particularly increased in the first weeks and annual stroke rates around 10–15% are repeatedly cited. (bobmanuel2023vertebralarteryinterventions pages 1-2, aminhanjani2010vertebrobasilarflowevaluation pages 1-2)

9. Inheritance and population

9.1 Epidemiology (key statistics)

  • Posterior-circulation ischemia due to vertebral artery disease accounts for ~20–25% of ischemic strokes. (bobmanuel2023vertebralarteryinterventions pages 1-2)
  • Symptomatic vertebrobasilar disease recurrence risk averages 10–15% per year. (bobmanuel2023vertebralarteryinterventions pages 1-2, aminhanjani2010vertebrobasilarflowevaluation pages 1-2)
  • Poor prognosis in obstructive vertebrobasilar disease managed medically: ~30% mortality at 2 years (review-cited). (bobmanuel2023vertebralarteryinterventions pages 1-2)
  • Vertebral artery stenosis/occlusion (VASO) “occurs in 5% of the normal population” (as reported in a 2023 surgical series background). (zhang2023microsurgicalrevascularizationof pages 1-2)
  • Vertebral artery hypoplasia frequency 2–6% (autopsy/angiogram). (bobmanuel2023vertebralarteryinterventions pages 3-4)

VAD incidence (relevant VAI subtype): - VAD contributes “around 1.0–1.1 per 100,000 population” (review). (amran2024vertebralarterydissection pages 1-2)

9.2 Inheritance pattern

Not established as a Mendelian disorder in typical atherosclerotic VAI/VBI. For VAD, connective tissue disease predisposition is discussed without specifying inheritance patterns or genes in retrieved text. (amran2024vertebralarterydissection pages 1-2)

10. Diagnostics

10.1 Imaging-based diagnostic strategy (real-world implementation)

A 2023 review states that Color duplex ultrasound (DUS) is used as a “first-line imaging strategy” in suspected vertebrobasilar ischemia and should be followed by CE-MRA or CTA before intervention decisions; DSA is the gold standard for defining lesions. (bobmanuel2023vertebralarteryinterventions pages 4-5)

10.2 Diagnostic performance metrics (selected)

From the same review: - Duplex criterion PSVr >2.2 for ≥50% proximal stenosis: 96% sensitivity / 89% specificity. (bobmanuel2023vertebralarteryinterventions pages 3-4) - CTA/MRA performance: reported sensitivity/specificity around 94–95%, and DSA carries 1–2% stroke risk. (bobmanuel2023vertebralarteryinterventions pages 3-4)

Traumatic vertebral artery injury (TVAI): - Pooled data: 91.7% underwent diagnostic CTA; 7.5% MRA; 3.0% DSA. (goyal2024asystematicreview pages 1-2) - One cited trauma study: CTA sensitivity ~98%, specificity ~100%; MRA sensitivity 47–60%. (goyal2024asystematicreview pages 5-7)

10.3 Hemodynamic assessment

VERiTAS emphasizes quantitative MRA (QMRA) for large-vessel flow measurement and risk stratification; symptom-based “hypoperfusion symptoms” poorly predict low/borderline flow (PPV 37.5%, NPV 65.5%). (aminhanjani2010vertebrobasilarflowevaluation pages 1-2, markus2022treatmentofposterior pages 4-5)

10.4 Differential diagnosis

Not systematically enumerated in the retrieved texts; practical differentials for posterior circulation symptoms include cardioembolic stroke, other intracranial stenoses, basilar artery occlusion, vestibular disorders, and nonvascular brainstem/cerebellar pathology.

11. Outcome / prognosis

11.1 Stroke recurrence and mortality

  • Annual stroke recurrence risk in symptomatic vertebrobasilar disease: ~10–15% per year (often cited). (bobmanuel2023vertebralarteryinterventions pages 1-2, aminhanjani2010vertebrobasilarflowevaluation pages 1-2)
  • Poor prognosis under medical therapy alone in obstructive vertebrobasilar disease: ~30% mortality at 2 years (review-cited). (bobmanuel2023vertebralarteryinterventions pages 1-2)

11.2 Post-procedural outcomes and complications (selected recent data)

  • Vertebrobasilar stenting cohort (VBS n=93): in-stent restenosis 12.9%; stented-territory infarction 22.6% over follow-up; diabetes and multiple stents strongly associated with long-term stented-territory infarction. (ryu2023instentrestenosisand pages 2-4, ryu2023instentrestenosisand pages 6-7)
  • Microsurgical series report clinical improvement with low perioperative stroke/death in selected cohorts, with cranial nerve complications (Horner’s syndrome, hoarseness) notable. (zhang2023microsurgicalrevascularizationof pages 1-2, liu2024applicationofmicrosurgical pages 1-2)

12. Treatment

12.1 Medical therapy (secondary prevention emphasis)

A 2023 review summarizes guideline-oriented management including risk factor modification and therapies such as antiplatelet and statins, with BP goals in that text of <140/90 mmHg (and diastolic <85 mmHg in diabetes). (bobmanuel2023vertebralarteryinterventions pages 4-5)

For posterior circulation stroke/TIA, a secondary-prevention review notes: - Short-term dual antiplatelet therapy after high-risk minor stroke/TIA is recommended by guidelines, with benefit mainly in the first ~3 weeks, then transition to monotherapy. (markus2022treatmentofposterior pages 4-5)

12.2 Acute reperfusion therapy (posterior circulation stroke)

  • IV thrombolysis appears to have similar benefit to anterior circulation and lower hemorrhage risk (meta-analysis estimates provided in review). (markus2022treatmentofposterior pages 2-3)
  • Mechanical thrombectomy has RCT-supported benefit for basilar artery occlusion, e.g., mRS 0–3 at 90 days 46% vs 22.8% in one RCT and 46.4% vs 24.3% in another. (markus2022treatmentofposterior pages 3-4)

12.3 Endovascular intervention for vertebral stenosis

Evidence remains mixed, with uncertainty about superiority over optimal medical therapy: - VAST: 30-day composite 5% (stent) vs 2% (OMT); 1-year territory stroke 9% vs 7%. (bobmanuel2023vertebralarteryinterventions pages 7-8) - VIST: stroke in 5 stent vs 12 medical; HR 0.40 (95% CI 0.14–1.13; p=0.08). (bobmanuel2023vertebralarteryinterventions pages 7-8)

Restenosis statistics: reported wide range 0–43% across studies; BMS 11–43%; meta-analysis cited DES 8.2% vs BMS 23.7% restenosis. (bobmanuel2023vertebralarteryinterventions pages 7-8, bobmanuel2023vertebralarteryinterventions pages 5-6)

12.4 Microsurgical / hybrid revascularization

Recent real-world data suggest microsurgical reconstruction is used when endovascular options are unsuitable or in restenosis: - Liu 2024 (n=34): postoperative arteries patent; no new in-hospital TIAs/events; mRS improved for 30 patients with all postoperative mRS <1; mean follow-up 10 months; one permanent Horner syndrome and one death from septic shock. (liu2024applicationofmicrosurgical pages 1-2) - Zhang 2023 (n=29): no perioperative stroke or death; mean follow-up 28.4 months; cranial nerve complications common; no target vessel restenosis reported. (zhang2023microsurgicalrevascularizationof pages 1-2, zhang2023microsurgicalrevascularizationof pages 4-5)

12.5 Relevant clinical trials (current applications)

  • NCT05885932: Drug-eluting stenting vs medical treatment for extracranial vertebral artery stenosis; recruiting; planned n=472. (bobmanuel2023vertebralarteryinterventions pages 7-8)
  • NCT03201432: Drug-eluting vs bare metal stents in symptomatic extracranial vertebral artery stenosis; completed; n=160. (bobmanuel2023vertebralarteryinterventions pages 7-8)

12.6 MAXO (Medical Action Ontology) term suggestions (examples)

(Provided as mappings; MAXO IDs not retrievable from the current evidence set.) - Antiplatelet therapy; dual antiplatelet therapy (markus2022treatmentofposterior pages 4-5) - Statin therapy / lipid-lowering therapy (bobmanuel2023vertebralarteryinterventions pages 4-5) - Blood pressure management (bobmanuel2023vertebralarteryinterventions pages 4-5) - CT angiography; MR angiography; digital subtraction angiography (bobmanuel2023vertebralarteryinterventions pages 3-4) - Endovascular stent placement (vertebral artery) (bobmanuel2023vertebralarteryinterventions pages 7-8) - Vertebral endarterectomy; artery transposition; bypass grafting (liu2024applicationofmicrosurgical pages 2-4)

13. Prevention

13.1 Primary prevention

A 2024 AHA/ASA primary prevention guideline explicitly states that for asymptomatic vertebral artery stenosis there are limited large-scale data and thus the guideline “cannot develop comprehensive, evidence-based recommendations,” focusing instead on asymptomatic carotid stenosis. This implies prevention is largely through general cardiovascular risk reduction rather than vertebral-specific screening/revascularization strategies. (bushnell20242024guidelinefor pages 25-26)

13.2 Secondary/tertiary prevention

Secondary prevention is centered on aggressive vascular risk factor treatment and antiplatelet therapy, with consideration of short-term DAPT after minor stroke/TIA. (markus2022treatmentofposterior pages 4-5, bobmanuel2023vertebralarteryinterventions pages 4-5)

14. Other species / natural disease

No evidence in the retrieved sources about naturally occurring vertebral artery insufficiency as a comparable veterinary disease entity.

15. Model organisms

No model organism or experimental induced model evidence was identified in the retrieved sources.

Recent developments and expert analysis (prioritizing 2023–2024)

1) Shift toward quantifying risk beyond symptoms: VERiTAS-related work emphasizes that symptom patterns alone may not reliably identify hemodynamic compromise; quantitative flow imaging is more directly linked to risk stratification. (aminhanjani2010vertebrobasilarflowevaluation pages 1-2, markus2022treatmentofposterior pages 4-5)

2) Interventional practice remains active but evidence-limited: Contemporary reviews characterize vertebral artery stenting as widely used with good technical success yet without definitive RCT proof of superiority over optimal medical therapy, especially for intracranial disease where peri-procedural risk is higher. (bobmanuel2023vertebralarteryinterventions pages 7-8, markus2022treatmentofposterior pages 5-8)

3) Real-world microsurgical revival in select niches (2023–2024): Single-center series report feasibility of vertebral endarterectomy/transposition/bypass in patients unsuited for endovascular therapy or with restenosis, with improved functional outcomes in selected cohorts but cranial nerve morbidity remains salient. (liu2024applicationofmicrosurgical pages 1-2, zhang2023microsurgicalrevascularizationof pages 4-5)

4) Device technology and restenosis surveillance: Observational data quantify clinically important rates of stented-territory infarction after vertebrobasilar stenting and identify predictors (e.g., diabetes, multiple stents, clopidogrel resistance). This supports individualized follow-up and antiplatelet optimization strategies in practice. (ryu2023instentrestenosisand pages 2-4, ryu2023instentrestenosisand pages 6-7)

Key abstract quotes (verbatim excerpts)

  • Bob-Manuel 2023 (Current Cardiology Reviews; 2023-01; https://doi.org/10.2174/1573403x18666220317093131): “Patients with posterior circulation ischemia due to vertebral artery stenosis account for 20 to 25% of ischemic strokes…” and “with an annual stroke rate of 10 to 15%.” (bobmanuel2023vertebralarteryinterventions pages 1-2)

  • Amin-Hanjani 2010 VERiTAS rationale (International Journal of Stroke; 2010-12; https://doi.org/10.1111/j.1747-4949.2010.00528.x): symptomatic vertebrobasilar disease carries a high recurrent stroke risk “averaging 10–15% per year.” (aminhanjani2010vertebrobasilarflowevaluation pages 1-2)

  • Bushnell 2024 AHA/ASA Primary Prevention of Stroke guideline (Stroke; 2024-12; https://doi.org/10.1161/str.0000000000000475): limited large-scale data for asymptomatic vertebral stenosis—authors “cannot develop comprehensive, evidence-based recommendations.” (bushnell20242024guidelinefor pages 25-26)

  • Goyal 2024 traumatic vertebral artery injury meta-analysis (Global Spine Journal; 2024-11; https://doi.org/10.1177/21925682231209631): pooled VAI incidence “.95% (95% CI 0.65-1.29)” and posterior stroke risk “8.87% (95% CI 5.34- 12.99).” (goyal2024asystematicreview pages 1-2)

Evidence map table

The following table consolidates the key quantitative findings, diagnostic metrics, mechanistic framing, and treatment evidence, including active clinical trials.

Domain Key findings Evidence type Citations
Definitions / nomenclature Vertebral artery insufficiency (VAI) is best understood as symptomatic posterior-circulation ischemia caused by reduced flow or embolic complications from vertebral artery pathology; in practice literature often uses vertebrobasilar insufficiency (VBI), vertebrobasilar disease (VBD), vertebral artery stenosis/occlusion (VAS/VASO), and posterior circulation ischemia with partial overlap. Reviews commonly discuss VAI/VBI under the broader umbrella of symptomatic vertebral or vertebrobasilar atherosclerotic disease rather than as a distinct monogenic disease entity. Narrative review, prospective study rationale (bobmanuel2023vertebralarteryinterventions pages 1-2, aminhanjani2010vertebrobasilarflowevaluation pages 1-2, bobmanuel2023vertebralarteryinterventions pages 2-3)
Epidemiology / prognosis Posterior-circulation ischemia due to vertebral artery disease accounts for about 20–25% of ischemic strokes; one review notes posterior-circulation strokes comprise about one-fifth of all strokes, while VERiTAS background cites up to 30–40% of ischemic strokes in the posterior circulation. Symptomatic vertebrobasilar disease has high early recurrence; medically treated patients have an annual stroke rate of 10–15%, with particularly high risk in the first weeks. Obstructive vertebrobasilar disease managed medically has about 30% mortality at 2 years. In one secondary-prevention review, 90-day recurrent stroke was 33% for basilar/intracranial vertebral stenosis versus 16% for extracranial vertebral stenosis. Review, prospective cohort/rationale (bobmanuel2023vertebralarteryinterventions pages 1-2, aminhanjani2010vertebrobasilarflowevaluation pages 1-2, markus2022treatmentofposterior pages 4-5)
Major mechanisms / pathophysiology Major etiologies include atherosclerotic stenosis/occlusion (dominant mechanism), with less common causes including dissection, trauma, congenital anomalies/hypoplasia, extrinsic compression, and vasculitis. Stroke mechanism is heterogeneous: VERiTAS-related work supports hemodynamic compromise as a strong predictor of future stroke, but infarct-pattern analysis shows both hemodynamic and embolic / perforator-plaque mechanisms occur. Traumatic vertebral artery injury/dissection is a separate but clinically relevant VAI mechanism, especially after cervical trauma. Review, observational cohort, systematic review/meta-analysis (aminhanjani2010vertebrobasilarflowevaluation pages 1-2, goyal2024asystematicreview pages 5-7, goyal2024asystematicreview pages 1-2, bobmanuel2023vertebralarteryinterventions pages 2-3)
Hemodynamic risk stratification In symptomatic vertebrobasilar disease, quantitative MRA (QMRA)-measured distal flow is more informative than symptom pattern alone. VERiTAS analyses found flow compromise robustly predicts subsequent stroke risk; by contrast, “hypoperfusion symptoms” alone had poor predictive value (PPV 37.5%, NPV 65.5%) for low/borderline flow and were not associated with stroke outcome. Prospective observational study / post hoc analysis (aminhanjani2010vertebrobasilarflowevaluation pages 1-2, markus2022treatmentofposterior pages 4-5)
Diagnostics: DUS / ultrasound Color duplex ultrasound (DUS) is commonly recommended as first-line screening in suspected vertebrobasilar ischemia, but positive studies usually require confirmatory CTA or CE-MRA before intervention decisions. Reported duplex criteria for proximal stenosis include PSVr >2.2 for ≥50% stenosis with 96% sensitivity / 89% specificity; other thresholds reported include PSV >108 cm/s, EDV >36 cm/s, EDVr >1.7. DUS has lower overall sensitivity than CTA/MRA but good specificity. Review / guideline-summary review (bobmanuel2023vertebralarteryinterventions pages 4-5, bobmanuel2023vertebralarteryinterventions pages 3-4)
Diagnostics: CTA / MRA / DSA CTA and CE-MRA/MRA are the main confirmatory noninvasive tests; review data cite sensitivity/specificity around 94–95%, with CE-MRA sometimes slightly outperforming CTA. DSA remains the gold standard for lesion definition but is invasive and carries a 1–2% stroke risk. In traumatic vertebral artery injury, CTA is the preferred acute screening test; pooled trauma data showed 91.7% CTA, 7.5% MRA, 3.0% DSA, and one cited study reported CTA sensitivity near 98% and specificity near 100%, while MRA sensitivity was lower (47–60%). Review, systematic review/meta-analysis (bobmanuel2023vertebralarteryinterventions pages 4-5, bobmanuel2023vertebralarteryinterventions pages 3-4, goyal2024asystematicreview pages 5-7, goyal2024asystematicreview pages 1-2)
Medical treatment / prevention Guideline-concordant therapy centers on aggressive vascular risk-factor control: antiplatelet therapy, statin therapy, BP control, diabetes management, smoking cessation, and lifestyle modification. AHA/ASA-aligned review text cites BP goal <140/90 mmHg (diastolic <85 mmHg in diabetes). For posterior-circulation minor stroke/TIA, reviews support short-term DAPT (aspirin + clopidogrel, or aspirin + ticagrelor in guideline frameworks) for the early high-risk period, with benefit concentrated in approximately the first 3 weeks, then transition to single antiplatelet therapy. For asymptomatic vertebral stenosis, high-quality evidence is limited; the 2024 primary-prevention guideline notes insufficient data to make comprehensive evidence-based recommendations specific to asymptomatic vertebral artery stenosis. Review, guideline, trial-informed secondary-prevention review (bobmanuel2023vertebralarteryinterventions pages 4-5, markus2022treatmentofposterior pages 4-5, bushnell20242024guidelinefor pages 25-26)
Acute posterior-circulation stroke care relevant to VAI/VBI For posterior-circulation stroke broadly, IV thrombolysis appears at least as effective as for anterior circulation and may have lower symptomatic ICH risk; mechanical thrombectomy now has convincing benefit for basilar artery occlusion (e.g., 90-day mRS 0–3 in 46% vs 22.8% in ATTENTION-like data, and 46.4% vs 24.3% in BAOCHE-like data). Evidence remains sparse for isolated vertebral artery occlusions. Review of RCTs/observational studies (markus2022treatmentofposterior pages 1-2, markus2022treatmentofposterior pages 2-3, markus2022treatmentofposterior pages 3-4)
Stenting vs medical therapy: overall interpretation Endovascular angioplasty/stenting is technically feasible and widely used, but superiority over best medical therapy remains unproven. Reviews note vertebral revascularization may be considered for symptomatic extracranial lesions ≥50% with recurrent ischemia despite optimal medical therapy (ESC Class IIb wording in review summary), while intracranial vertebral/basilar stenosis is generally better managed medically because peri-procedural risk is higher. Review / guideline-summary review / RCT synthesis (bobmanuel2023vertebralarteryinterventions pages 4-5, markus2022treatmentofposterior pages 1-2, markus2022treatmentofposterior pages 5-8)
Vertebral stenting trial data VAST: 30-day composite outcome 5% (3/57) in stenting vs 2% (1/58) in optimal medical therapy; 1-year vertebrobasilar-territory stroke 9% vs 7%. VIST: strokes in 5 stented vs 12 medical patients; HR 0.40 (95% CI 0.14–1.13; p=0.08), suggesting possible but unproven benefit, especially extracranially. For intracranial stenosis generally, SAMMPRIS showed 30-day stroke/death 14.7% with stenting vs 5.8% with medical therapy; basilar stenosis had particularly high peri-procedural risk (20.8% vs 6.7% in other arteries). RCTs summarized in reviews (bobmanuel2023vertebralarteryinterventions pages 7-8, markus2022treatmentofposterior pages 5-8)
Restenosis / post-stent outcomes Reported vertebral in-stent restenosis varies widely: 0–43% across studies; early bare-metal stent series reported 11–43% restenosis, while a meta-analysis cited 8.2% restenosis with drug-eluting stents vs 23.7% with bare-metal stents. In a 2023 vertebrobasilar-stenting cohort (n=93 VBS), in-stent restenosis was 12.9%, with cumulative rates 10.4%, 15.7%, 18.1% at 12/24/36 months; stented-territory infarction was 22.6% overall, higher than carotid stenting. Predictors included higher HbA1c, clopidogrel resistance / low platelet inhibition, diabetes, and use of ≥2 stents. Review, retrospective observational cohort (ryu2023instentrestenosisand pages 4-6, ryu2023instentrestenosisand pages 2-4, ryu2023instentrestenosisand pages 1-2, bobmanuel2023vertebralarteryinterventions pages 7-8, bobmanuel2023vertebralarteryinterventions pages 5-6)
Microsurgical / hybrid real-world implementations Zhang 2023: 29 symptomatic proximal vertebral lesions; techniques included endarterectomy, transposition, hybrid endarterectomy+stent; no perioperative stroke or death, mean follow-up 28.4 months, most improved clinically, no anastomotic stenosis on follow-up imaging. Liu 2024: 34 patients unsuitable for endovascular treatment; pre-op CTA/CTP/MRA, post-op vessels patent, 30/34 improved mRS with all postoperative mRS <1, mean follow-up 10 months; one death from septic shock unrelated to cerebrovascular event, one residual moderate restenosis, six temporary complications, one permanent Horner syndrome. These series support surgery as a niche option for refractory anatomy, restenosis, or endovascular-unsuitable disease. Single-center retrospective observational series (zhang2023microsurgicalrevascularizationof pages 4-5, zhang2023microsurgicalrevascularizationof pages 2-4, zhang2023microsurgicalrevascularizationof pages 5-6, liu2024applicationofmicrosurgical pages 1-2, liu2024applicationofmicrosurgical pages 2-4, zhang2023microsurgicalrevascularizationof pages 1-2, liu2024applicationofmicrosurgical pages 4-6)
Traumatic/dissection-associated vertebral insufficiency In cervical trauma, pooled incidence of vertebral artery injury was 0.95% (95% CI 0.65–1.29) and pooled posterior stroke risk among VAI cases was 8.87% (95% CI 5.34–12.99). Most were evaluated with CTA, and management varied across conservative care, antiplatelets, anticoagulation, combined therapy, and surgical/endovascular intervention. This is a clinically important VAI subtype but distinct from chronic atherosclerotic VBI. Systematic review/meta-analysis (goyal2024asystematicreview pages 5-7, goyal2024asystematicreview pages 1-2)
Real-world trials / implementations NCT05885932: recruiting randomized trial, Drug-eluting Stenting Versus Medical Treatment for Extracranial Vertebral Artery Stenosis, planned n=472. NCT03201432: completed phase 2/3 trial comparing drug-eluting vs bare-metal stents for symptomatic extracranial vertebral stenosis, n=160. Additional antiplatelet optimization after cerebrovascular stenting: NCT06301776 (post-BRIDGE dual antiplatelet/ticagrelor strategy, recruiting, n=560). These trials show ongoing real-world implementation emphasis on extracranial vertebral stenting technology and post-stent antiplatelet regimens rather than established routine use. Registered interventional clinical trials (bobmanuel2023vertebralarteryinterventions pages 7-8)

Table: This table condenses definitions, mechanisms, diagnostics, prognosis, treatments, and active implementation examples for vertebral artery insufficiency / vertebrobasilar insufficiency. It is designed as a compact evidence map for rapid use in a disease knowledge base.

References

  1. (bobmanuel2023vertebralarteryinterventions pages 1-2): Tamunoinemi Bob-Manuel, Oscar Maitas, Justin Price, Abdullah Noor, Koyenum Obi, Nelson Okoh, Kiran Garikapati, Jeong Kim, Sanjida Jahan, and James S. Jenkins. Vertebral artery interventions: a comprehensive updated review. Current Cardiology Reviews, Jan 2023. URL: https://doi.org/10.2174/1573403x18666220317093131, doi:10.2174/1573403x18666220317093131. This article has 21 citations.

  2. (aminhanjani2010vertebrobasilarflowevaluation pages 1-2): Sepideh Amin-Hanjani, Linda Rose-Finnell, DeJuran Richardson, Sean Ruland, Dilip Pandey, Keith R. Thulborn, David S. Liebeskind, Gregory J. Zipfel, Mitchell S. V. Elkind, Jeffrey Kramer, Frank L. Silver, Scott E. Kasner, Louis R. Caplan, Colin P. Derdeyn, Philip B. Gorelick, and Fady T. Charbel. Vertebrobasilar flow evaluation and risk of transient ischaemic attack and stroke study (veritas): rationale and design. International Journal of Stroke, 5:499-505, Dec 2010. URL: https://doi.org/10.1111/j.1747-4949.2010.00528.x, doi:10.1111/j.1747-4949.2010.00528.x. This article has 59 citations and is from a peer-reviewed journal.

  3. (bobmanuel2023vertebralarteryinterventions pages 4-5): Tamunoinemi Bob-Manuel, Oscar Maitas, Justin Price, Abdullah Noor, Koyenum Obi, Nelson Okoh, Kiran Garikapati, Jeong Kim, Sanjida Jahan, and James S. Jenkins. Vertebral artery interventions: a comprehensive updated review. Current Cardiology Reviews, Jan 2023. URL: https://doi.org/10.2174/1573403x18666220317093131, doi:10.2174/1573403x18666220317093131. This article has 21 citations.

  4. (bobmanuel2023vertebralarteryinterventions pages 2-3): Tamunoinemi Bob-Manuel, Oscar Maitas, Justin Price, Abdullah Noor, Koyenum Obi, Nelson Okoh, Kiran Garikapati, Jeong Kim, Sanjida Jahan, and James S. Jenkins. Vertebral artery interventions: a comprehensive updated review. Current Cardiology Reviews, Jan 2023. URL: https://doi.org/10.2174/1573403x18666220317093131, doi:10.2174/1573403x18666220317093131. This article has 21 citations.

  5. (bobmanuel2023vertebralarteryinterventions pages 3-4): Tamunoinemi Bob-Manuel, Oscar Maitas, Justin Price, Abdullah Noor, Koyenum Obi, Nelson Okoh, Kiran Garikapati, Jeong Kim, Sanjida Jahan, and James S. Jenkins. Vertebral artery interventions: a comprehensive updated review. Current Cardiology Reviews, Jan 2023. URL: https://doi.org/10.2174/1573403x18666220317093131, doi:10.2174/1573403x18666220317093131. This article has 21 citations.

  6. (zhang2023microsurgicalrevascularizationof pages 1-2): Tongfu Zhang, Donglin Zhou, Yangyang Xu, Maogui Li, Jianfeng Zhuang, Hai Wang, Weiying Zhong, Chao Chen, Hong Kuang, Donghai Wang, and Yunyan Wang. Microsurgical revascularization of a symptomatic proximal vertebral artery: pilot experiences from a single center. Frontiers in Neurology, Jul 2023. URL: https://doi.org/10.3389/fneur.2023.1202565, doi:10.3389/fneur.2023.1202565. This article has 3 citations and is from a peer-reviewed journal.

  7. (markus2022treatmentofposterior pages 1-2): Hugh S Markus and Patrik Michel. Treatment of posterior circulation stroke: acute management and secondary prevention. International Journal of Stroke, 17:723-732, Jun 2022. URL: https://doi.org/10.1177/17474930221107500, doi:10.1177/17474930221107500. This article has 95 citations and is from a peer-reviewed journal.

  8. (bushnell20242024guidelinefor pages 25-26): Cheryl Bushnell, Walter N. Kernan, Anjail Z. Sharrief, Seemant Chaturvedi, John W. Cole, William K. Cornwell, Christine Cosby-Gaither, Sarah Doyle, Larry B. Goldstein, Olive Lennon, Deborah A. Levine, Mary Love, Eliza Miller, Mai Nguyen-Huynh, Jennifer Rasmussen-Winkler, Kathryn M. Rexrode, Nicole Rosendale, Satyam Sarma, Daichi Shimbo, Alexis N. Simpkins, Erica S. Spatz, Lisa R. Sun, Vin Tangpricha, Dawn Turnage, Gabriela Velazquez, and Paul K. Whelton. 2024 guideline for the primary prevention of stroke: a guideline from the american heart association/american stroke association. Stroke, Dec 2024. URL: https://doi.org/10.1161/str.0000000000000475, doi:10.1161/str.0000000000000475. This article has 333 citations and is from a highest quality peer-reviewed journal.

  9. (ryu2023instentrestenosisand pages 2-4): Jae-Chan Ryu, Jae-Han Bae, Sang Hee Ha, Boseong Kwon, Yunsun Song, Deok Hee Lee, Jun Young Chang, Dong-Wha Kang, Sun U. Kwon, Jong S. Kim, and Bum Joon Kim. In-stent restenosis and stented-territory infarction after carotid and vertebrobasilar artery stenting. BMC Neurology, Feb 2023. URL: https://doi.org/10.1186/s12883-023-03110-z, doi:10.1186/s12883-023-03110-z. This article has 11 citations and is from a peer-reviewed journal.

  10. (liu2024applicationofmicrosurgical pages 1-2): Mingyuan Liu, Peiguang Yan, Mingxin Wang, Jia Guo, Wei Liu, Ganchun Wu, Lufei Wang, Jingjing Liu, and Li Li. Application of microsurgical surgery in patients with proximal vertebral artery stenosis unsuited for endovascular treatment: a single-center retrospective study. Neurosurgical Review, Dec 2024. URL: https://doi.org/10.1007/s10143-024-03153-x, doi:10.1007/s10143-024-03153-x. This article has 1 citations and is from a peer-reviewed journal.

  11. (goyal2024asystematicreview pages 1-2): Kartik Goyal, Jesvin T. Sunny, Conor S. Gillespie, Martin Wilby, Simon R. Clark, Radek Kaiser, Michael G. Fehlings, and Nisaharan Srikandarajah. A systematic review and meta-analysis of vertebral artery injury after cervical spine trauma. Global Spine Journal, 14:1356-1368, Nov 2024. URL: https://doi.org/10.1177/21925682231209631, doi:10.1177/21925682231209631. This article has 21 citations and is from a peer-reviewed journal.

  12. (amran2024vertebralarterydissection pages 1-2): Muhammad Yunus Amran, Irbab Hawari, Fitri Jafani La’biran, Siti Giranti Ardilia Gunadi, and Lisa Tenriesa Muslich. Vertebral artery dissection from etiopathogenesis to management therapy: a narrative review with neuroimaging’s case illustration. The Egyptian Journal of Neurology, Psychiatry and Neurosurgery, Sep 2024. URL: https://doi.org/10.1186/s41983-024-00893-x, doi:10.1186/s41983-024-00893-x. This article has 6 citations.

  13. (aminhanjani2015hemodynamicfeaturesof pages 7-10): Sepideh Amin-Hanjani, Xinjian Du, Linda Rose-Finnell, Dilip K. Pandey, DeJuran Richardson, Keith R. Thulborn, Mitchell S.V. Elkind, Gregory J. Zipfel, David S. Liebeskind, Frank L. Silver, Scott E. Kasner, Victor A. Aletich, Louis R. Caplan, Colin P. Derdeyn, Philip B. Gorelick, Fady T. Charbel, Hui Xie, Michael P. Flannery, Hagai Ganin, Sean Ruland, Rebecca Grysiewicz, Aslam Khaja, Laura Pedelty, Fernando Testai, Archie Ong, Noam Epstein, Hurmina Muqtadar, Karriem Watson, Nada Mlinarevich, Maureen Hillmann, Joy Hirsch, Stephen Dashnaw, Philip M. Meyers, Josh Z. Willey, Edwina McNeill-Simaan, Veronica Perez, Alberto Canaan, Wayna Paulino-Hernandez, Katie Vo, Glenn Foster, Andria Ford, Abdullah Nassief, Abbie Bradley, Jannie Serna-Northway, Kristi Kraus, Lina Shiwani, Nancy Hantler, Jeffrey Alger, Sergio Godinez, Jeffrey L. Saver, Latisha Ali, Doojin Kim, Matthew Tenser, Michael Froehler, Radoslav Raychev, Sarah Song, Bruce Ovbiagele, Hermelinda Abcede, Peter Adamczyk, Neal Rao, Anil Yallapragada, Royya Modir, Jason Hinman, Aaron Tansy, Mateo Calderon-Arnulphi, Sunil Sheth, Alireza Noorian, Kwan Ng, Conrad Liang, Jignesh Gadhia, Hannah Smith, Gilda Avila, Johanna Avelar, David Mikulis, Jorn Fierstra, Eugen Hlasny, Leanne K. Casaubon, Mervyn Vergouwen, J.C. Martin del Campo, Cheryl S. Jaigobin, Cherissa Astorga, Libby Kalman, Jeffrey Kramer, Susan Vaughan, Laura Owens, Brett Kissela, Tanya N. Turan, Tom P. Jacobs, and Scott Janis. Hemodynamic features of symptomatic vertebrobasilar disease. Stroke, 46:1850–1856, Jul 2015. URL: https://doi.org/10.1161/strokeaha.115.009215, doi:10.1161/strokeaha.115.009215. This article has 66 citations and is from a highest quality peer-reviewed journal.

  14. (aminhanjani2015hemodynamicfeaturesof pages 10-15): Sepideh Amin-Hanjani, Xinjian Du, Linda Rose-Finnell, Dilip K. Pandey, DeJuran Richardson, Keith R. Thulborn, Mitchell S.V. Elkind, Gregory J. Zipfel, David S. Liebeskind, Frank L. Silver, Scott E. Kasner, Victor A. Aletich, Louis R. Caplan, Colin P. Derdeyn, Philip B. Gorelick, Fady T. Charbel, Hui Xie, Michael P. Flannery, Hagai Ganin, Sean Ruland, Rebecca Grysiewicz, Aslam Khaja, Laura Pedelty, Fernando Testai, Archie Ong, Noam Epstein, Hurmina Muqtadar, Karriem Watson, Nada Mlinarevich, Maureen Hillmann, Joy Hirsch, Stephen Dashnaw, Philip M. Meyers, Josh Z. Willey, Edwina McNeill-Simaan, Veronica Perez, Alberto Canaan, Wayna Paulino-Hernandez, Katie Vo, Glenn Foster, Andria Ford, Abdullah Nassief, Abbie Bradley, Jannie Serna-Northway, Kristi Kraus, Lina Shiwani, Nancy Hantler, Jeffrey Alger, Sergio Godinez, Jeffrey L. Saver, Latisha Ali, Doojin Kim, Matthew Tenser, Michael Froehler, Radoslav Raychev, Sarah Song, Bruce Ovbiagele, Hermelinda Abcede, Peter Adamczyk, Neal Rao, Anil Yallapragada, Royya Modir, Jason Hinman, Aaron Tansy, Mateo Calderon-Arnulphi, Sunil Sheth, Alireza Noorian, Kwan Ng, Conrad Liang, Jignesh Gadhia, Hannah Smith, Gilda Avila, Johanna Avelar, David Mikulis, Jorn Fierstra, Eugen Hlasny, Leanne K. Casaubon, Mervyn Vergouwen, J.C. Martin del Campo, Cheryl S. Jaigobin, Cherissa Astorga, Libby Kalman, Jeffrey Kramer, Susan Vaughan, Laura Owens, Brett Kissela, Tanya N. Turan, Tom P. Jacobs, and Scott Janis. Hemodynamic features of symptomatic vertebrobasilar disease. Stroke, 46:1850–1856, Jul 2015. URL: https://doi.org/10.1161/strokeaha.115.009215, doi:10.1161/strokeaha.115.009215. This article has 66 citations and is from a highest quality peer-reviewed journal.

  15. (markus2022treatmentofposterior pages 3-4): Hugh S Markus and Patrik Michel. Treatment of posterior circulation stroke: acute management and secondary prevention. International Journal of Stroke, 17:723-732, Jun 2022. URL: https://doi.org/10.1177/17474930221107500, doi:10.1177/17474930221107500. This article has 95 citations and is from a peer-reviewed journal.

  16. (amran2024vertebralarterydissection pages 6-8): Muhammad Yunus Amran, Irbab Hawari, Fitri Jafani La’biran, Siti Giranti Ardilia Gunadi, and Lisa Tenriesa Muslich. Vertebral artery dissection from etiopathogenesis to management therapy: a narrative review with neuroimaging’s case illustration. The Egyptian Journal of Neurology, Psychiatry and Neurosurgery, Sep 2024. URL: https://doi.org/10.1186/s41983-024-00893-x, doi:10.1186/s41983-024-00893-x. This article has 6 citations.

  17. (markus2022treatmentofposterior pages 4-5): Hugh S Markus and Patrik Michel. Treatment of posterior circulation stroke: acute management and secondary prevention. International Journal of Stroke, 17:723-732, Jun 2022. URL: https://doi.org/10.1177/17474930221107500, doi:10.1177/17474930221107500. This article has 95 citations and is from a peer-reviewed journal.

  18. (goyal2024asystematicreview pages 5-7): Kartik Goyal, Jesvin T. Sunny, Conor S. Gillespie, Martin Wilby, Simon R. Clark, Radek Kaiser, Michael G. Fehlings, and Nisaharan Srikandarajah. A systematic review and meta-analysis of vertebral artery injury after cervical spine trauma. Global Spine Journal, 14:1356-1368, Nov 2024. URL: https://doi.org/10.1177/21925682231209631, doi:10.1177/21925682231209631. This article has 21 citations and is from a peer-reviewed journal.

  19. (ryu2023instentrestenosisand pages 6-7): Jae-Chan Ryu, Jae-Han Bae, Sang Hee Ha, Boseong Kwon, Yunsun Song, Deok Hee Lee, Jun Young Chang, Dong-Wha Kang, Sun U. Kwon, Jong S. Kim, and Bum Joon Kim. In-stent restenosis and stented-territory infarction after carotid and vertebrobasilar artery stenting. BMC Neurology, Feb 2023. URL: https://doi.org/10.1186/s12883-023-03110-z, doi:10.1186/s12883-023-03110-z. This article has 11 citations and is from a peer-reviewed journal.

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  22. (bobmanuel2023vertebralarteryinterventions pages 5-6): Tamunoinemi Bob-Manuel, Oscar Maitas, Justin Price, Abdullah Noor, Koyenum Obi, Nelson Okoh, Kiran Garikapati, Jeong Kim, Sanjida Jahan, and James S. Jenkins. Vertebral artery interventions: a comprehensive updated review. Current Cardiology Reviews, Jan 2023. URL: https://doi.org/10.2174/1573403x18666220317093131, doi:10.2174/1573403x18666220317093131. This article has 21 citations.

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  24. (liu2024applicationofmicrosurgical pages 2-4): Mingyuan Liu, Peiguang Yan, Mingxin Wang, Jia Guo, Wei Liu, Ganchun Wu, Lufei Wang, Jingjing Liu, and Li Li. Application of microsurgical surgery in patients with proximal vertebral artery stenosis unsuited for endovascular treatment: a single-center retrospective study. Neurosurgical Review, Dec 2024. URL: https://doi.org/10.1007/s10143-024-03153-x, doi:10.1007/s10143-024-03153-x. This article has 1 citations and is from a peer-reviewed journal.

  25. (markus2022treatmentofposterior pages 5-8): Hugh S Markus and Patrik Michel. Treatment of posterior circulation stroke: acute management and secondary prevention. International Journal of Stroke, 17:723-732, Jun 2022. URL: https://doi.org/10.1177/17474930221107500, doi:10.1177/17474930221107500. This article has 95 citations and is from a peer-reviewed journal.

  26. (ryu2023instentrestenosisand pages 4-6): Jae-Chan Ryu, Jae-Han Bae, Sang Hee Ha, Boseong Kwon, Yunsun Song, Deok Hee Lee, Jun Young Chang, Dong-Wha Kang, Sun U. Kwon, Jong S. Kim, and Bum Joon Kim. In-stent restenosis and stented-territory infarction after carotid and vertebrobasilar artery stenting. BMC Neurology, Feb 2023. URL: https://doi.org/10.1186/s12883-023-03110-z, doi:10.1186/s12883-023-03110-z. This article has 11 citations and is from a peer-reviewed journal.

  27. (ryu2023instentrestenosisand pages 1-2): Jae-Chan Ryu, Jae-Han Bae, Sang Hee Ha, Boseong Kwon, Yunsun Song, Deok Hee Lee, Jun Young Chang, Dong-Wha Kang, Sun U. Kwon, Jong S. Kim, and Bum Joon Kim. In-stent restenosis and stented-territory infarction after carotid and vertebrobasilar artery stenting. BMC Neurology, Feb 2023. URL: https://doi.org/10.1186/s12883-023-03110-z, doi:10.1186/s12883-023-03110-z. This article has 11 citations and is from a peer-reviewed journal.

  28. (zhang2023microsurgicalrevascularizationof pages 2-4): Tongfu Zhang, Donglin Zhou, Yangyang Xu, Maogui Li, Jianfeng Zhuang, Hai Wang, Weiying Zhong, Chao Chen, Hong Kuang, Donghai Wang, and Yunyan Wang. Microsurgical revascularization of a symptomatic proximal vertebral artery: pilot experiences from a single center. Frontiers in Neurology, Jul 2023. URL: https://doi.org/10.3389/fneur.2023.1202565, doi:10.3389/fneur.2023.1202565. This article has 3 citations and is from a peer-reviewed journal.

  29. (zhang2023microsurgicalrevascularizationof pages 5-6): Tongfu Zhang, Donglin Zhou, Yangyang Xu, Maogui Li, Jianfeng Zhuang, Hai Wang, Weiying Zhong, Chao Chen, Hong Kuang, Donghai Wang, and Yunyan Wang. Microsurgical revascularization of a symptomatic proximal vertebral artery: pilot experiences from a single center. Frontiers in Neurology, Jul 2023. URL: https://doi.org/10.3389/fneur.2023.1202565, doi:10.3389/fneur.2023.1202565. This article has 3 citations and is from a peer-reviewed journal.

  30. (liu2024applicationofmicrosurgical pages 4-6): Mingyuan Liu, Peiguang Yan, Mingxin Wang, Jia Guo, Wei Liu, Ganchun Wu, Lufei Wang, Jingjing Liu, and Li Li. Application of microsurgical surgery in patients with proximal vertebral artery stenosis unsuited for endovascular treatment: a single-center retrospective study. Neurosurgical Review, Dec 2024. URL: https://doi.org/10.1007/s10143-024-03153-x, doi:10.1007/s10143-024-03153-x. This article has 1 citations and is from a peer-reviewed journal.