Home / Deep Research / Coronary Arterial Fistulas

Coronary Arterial Fistulas

1. Disease Information

2026-05-05
Falcon MONDO:0016081 Model: Edison Scientific Literature 24 citations

1. Disease Information

1.1 Concise overview and definition

CAF is defined as a “direct communication of the epicardial coronary artery with one of the four chambers or the major vessels of the heart or chest” (review text) (kumar2023coronaryarteryfistula pages 1-2). A closely aligned CT-imaging definition states: “Coronary artery fistulas (CAFs) are abnormal connections of the coronary arteries that bypass the myocardial capillary bed and terminate into chambers of the heart or major blood vessels.” (li2020coronaryarteryfistulas pages 1-2).

Synonyms / alternative names (used variably in the literature): - Coronary artery fistula; coronary arterial fistula (kumar2023coronaryarteryfistula pages 1-2, tabib2023longtermoutcomeof pages 1-2) - Coronary arteriovenous fistula (CAVF) (li2020coronaryarteryfistulas pages 1-2) - Coronary-cameral fistula (CCF; fistula to a cardiac chamber) (li2020coronaryarteryfistulas pages 1-2) - Coronary–pulmonary artery fistula (a common drainage pattern) (li2020coronaryarteryfistulas pages 1-2)

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

The provided full texts did not include standardized identifiers (OMIM, Orphanet, ICD-10/ICD-11, MeSH, MONDO). Therefore, identifiers cannot be asserted from the evidence gathered in this run.

1.3 Evidence source type

The evidence synthesized here is largely aggregated from: - Narrative review(s) and imaging review(s) (kumar2023coronaryarteryfistula pages 1-2, li2020coronaryarteryfistulas pages 1-2) - Registry/observational cohorts (angiography registry, closure cohorts, CT series) (podolec2019presenceandcharacteristics pages 2-3, tabib2023longtermoutcomeof pages 2-4, sang2024thefunctionalimpact pages 1-2, wei2024outcomesoftranscatheter pages 1-3)

2. Etiology

2.1 Primary causes

Congenital developmental mechanism. A common mechanistic explanation is persistence/failure of regression of embryonic myocardial sinusoids that normally transform into the capillary network. The review states: “Failure of the regression of the sinusoids leads to fistulous communication between the coronary arteries and the cardiac chambers” (kumar2023coronaryarteryfistula pages 1-2). A CT-focused review similarly notes that if the embryologic sinusoidal spaces persist, “CAF will be formed.” (li2020coronaryarteryfistulas pages 1-2).

Acquired/iatrogenic causes. CAFs can be congenital or acquired. The review notes that acquired/sporadic causes (≈10%) are increasingly recognized with rising percutaneous coronary intervention (PCI), coronary artery bypass grafting (CABG), and chest radiation; it also lists myocardial infarction and vasculitis as causes during healing (kumar2023coronaryarteryfistula pages 1-2). A clinical cohort similarly notes acquisition after chest trauma, myectomy, coronary angioplasty, or bypass surgery (tabib2023longtermoutcomeof pages 1-2).

2.2 Risk factors

Evidence in the retrieved corpus supports contextual risk factors rather than genetic susceptibility loci: - Iatrogenic exposure (PCI/CABG/radiation) and prior myocardial injury/inflammation (MI, vasculitis) (kumar2023coronaryarteryfistula pages 1-2) - Association with other congenital cardiac abnormalities: In one interventional cohort, 17.1% had concurrent congenital abnormalities (e.g., PFO, ASD, single coronary ostium, repaired Tetralogy of Fallot) (tabib2023longtermoutcomeof pages 2-4).

2.3 Protective factors / gene–environment interactions

No evidence for genetic protective factors, environmental protective factors, or formal gene–environment interaction studies was found in the retrieved texts.

3. Phenotypes (clinical presentation)

3.1 Common phenotypes and characteristics

CAF presentation ranges from incidental/asymptomatic to complications driven by shunt size, anatomy, and steal physiology.

Age-related symptom emergence (natural history signal). The review reports that fistulas are often asymptomatic early but become symptomatic with age: “for age <20 years, only one-fifth of the fistulas are symptomatic, while more than two-thirds of the fistulas are symptomatic after the age of 60 years.” (kumar2023coronaryarteryfistula pages 2-4).

Symptoms/signs and complications described in reviews and cohorts include: - Dyspnea, fatigue, chest discomfort/angina; dizziness/syncope (kumar2023coronaryarteryfistula pages 2-4) - Heart failure / pulmonary congestion and myocardial infarction depending on shunt/steal (kumar2023coronaryarteryfistula pages 2-4) - Arrhythmias/conduction abnormalities; endocarditis; valvular regurgitation/papillary muscle dysfunction; rare hemopericardium/cardiac rupture (kumar2023coronaryarteryfistula pages 2-4) - Volume overload (72.6% in a pediatric interventional cohort), pulmonary hypertension (17.2%) and coronary aneurysm findings (LMCA aneurysm 6.8%; RCA aneurysm 3.4%) (tabib2023longtermoutcomeof pages 2-4)

3.2 Suggested HPO terms (examples)

Because HPO codes were not directly provided in the texts, terms below are suggested based on the described phenotypes: - Chest pain/angina: HP:0100749 (Chest pain) - Dyspnea on exertion: HP:0002875 (Dyspnea on exertion) - Heart failure: HP:0001635 (Congestive heart failure) - Myocardial ischemia: HP:0001709 (Myocardial ischemia) - Myocardial infarction: HP:0001658 (Myocardial infarction) - Arrhythmia: HP:0011675 (Arrhythmia) - Infective endocarditis: HP:0100587 (Endocarditis) - Pulmonary hypertension: HP:0002092 (Pulmonary hypertension) - Continuous murmur (when present): HP:0030048 (Continuous murmur) - Coronary artery aneurysm: HP:0032300 (Coronary artery aneurysm)

3.3 Quality of life impact

The retrieved texts did not report validated QoL instruments (e.g., SF-36, EQ-5D, PROMIS). Impact is inferred clinically via symptoms (angina/dyspnea/heart failure) but cannot be quantified here.

4. Genetic/Molecular Information

4.1 Causal genes and pathogenic variants

No causal genes, pathogenic variants, inheritance patterns, or recurrent syndromic gene associations were reported in the retrieved sources.

4.2 Mechanistic developmental biology (molecular-level proxy)

The literature in this run supports a developmental morphogenesis failure model (persistence of embryologic sinusoids), but it does not identify specific gene programs (kumar2023coronaryarteryfistula pages 1-2, li2020coronaryarteryfistulas pages 1-2).

4.3 Epigenetics, modifier genes, chromosomal abnormalities

No evidence was identified in the retrieved texts.

5. Mechanism / Pathophysiology

5.1 Causal chain (hemodynamic mechanism)

A central mechanism is diversion of high-pressure coronary flow into a low-resistance receiving chamber/vessel, bypassing the myocardial microcirculation. The review states: “The main pathophysiology of CAF is the drainage of high-pressure blood in the arteries into a low-resistance venous system through a channel that bypasses the natural low-pressure small arteriolar and capillary network in the myocardium.” (kumar2023coronaryarteryfistula pages 1-2). This can reduce distal myocardial perfusion (“steal phenomenon”), contributing to exertional angina/ischemia and, with larger shunts, volume overload and pulmonary hypertension/heart failure (kumar2023coronaryarteryfistula pages 2-4, sang2024thefunctionalimpact pages 1-2).

Physiologic evidence (2024): A QFR-based study showed that donor vessels supplying medium CAFs had lower baseline QFR than those supplying small CAFs (0.93±0.10 vs 0.98±0.03) and that QFR significantly improved after occlusion for medium CAFs (0.99±0.01 vs 0.93±0.10 pre-closure; p=0.01), supporting a functional steal effect reversible by closure (sang2024thefunctionalimpact pages 1-2).

5.2 Suggested GO biological process terms (examples)

Based on the reported mechanisms: - GO:0001525 angiogenesis (developmental vascular formation relevant to anomalous communications) - GO:0001944 vasculature development - GO:0003015 heart process - GO:0008015 blood circulation - GO:0003013 circulatory system process - GO:0001666 response to hypoxia / GO:0001525 (downstream ischemia-related processes; not directly measured molecularly here)

5.3 Suggested Cell Ontology (CL) terms (examples)

CAF is primarily an anatomic vascular malformation; implicated cell types in vessel wall and downstream myocardium include: - CL:0002543 endothelial cell - CL:0000187 smooth muscle cell - CL:0000746 cardiomyocyte

6. Diagnostics

6.1 Imaging and diagnostic modalities (current understanding)

Echocardiography (TTE/TEE). The review emphasizes TTE’s importance, but notes limited anatomic delineation and states: “Despite this, the diagnostic accuracy is still 35–50%.” (kumar2023coronaryarteryfistula pages 2-4). A closure cohort uses TTE for diagnosis and follow-up and lists typical echo findings (dilated/tortuous coronaries, enlarged chambers, regurgitant flows, diastolic flow reversal in aorta, reduced function) (tabib2023longtermoutcomeof pages 1-2).

Invasive angiography (IA). Traditionally a gold standard for defining origin/course and providing hemodynamics; often the initial modality where CAF is found incidentally (kumar2023coronaryarteryfistula pages 2-4).

CT coronary angiography (CTCA). The review explicitly states: “CTCA has become the gold standard diagnostic evaluation tool for CAF because of the higher temporal and spatial resolution compared with other imaging modalities.” (kumar2023coronaryarteryfistula pages 2-4). A CT series documents higher detection and detailed 3D anatomic depiction, with more incidental/asymptomatic CAFs found as CT use expands (li2020coronaryarteryfistulas pages 1-2).

MRI/CMR. The review notes MRI can delineate anatomy (including 3D MR angiography) but has lower spatial resolution and longer acquisition time than CTCA (kumar2023coronaryarteryfistula pages 2-4).

Figure evidence (imaging modalities): Extracted imaging figure panels from the 2023 review illustrate invasive angiography, CTCA confirmation, and MR angiography views for CAF diagnosis (kumar2023coronaryarteryfistula media bbccd634).

6.2 Differential diagnosis

The retrieved texts did not provide an explicit differential diagnosis list. In practice, differentials for continuous murmurs/abnormal coronary flow include PDA, arteriovenous malformations, ruptured sinus of Valsalva, anomalous coronary origins with collateralization, and other shunt lesions; however, these cannot be asserted from the evidence collected here.

7. Epidemiology, demographics, and prognosis

7.1 Incidence/prevalence (recently cited statistics)

CAF epidemiology varies by ascertainment method. - Review-reported estimates: “incidence is only 0.002% in the general population and 0.1% in all cardiac catheterisation patients” (kumar2023coronaryarteryfistula pages 1-2). - Large angiography registry (Poland; 298,558 angiograms): CAF prevalence 0.087% (261 cases) (podolec2019presenceandcharacteristics pages 2-3). - CT angiography series (21,966 CTCA studies): 73 CAFs (incidence 0.33%) and a summary of modality-dependent incidence ranges (0.05–0.30% invasive angiography; 0.17–0.9% CTCA cohorts; 0.002% general population) (li2020coronaryarteryfistulas pages 1-2).

7.2 Anatomy distribution (origin and drainage)

7.3 Outcomes / prognosis

Prognosis is heterogeneous and anatomy-dependent; modern cohorts support generally favorable procedural safety for selected patients undergoing transcatheter closure. - Interventional cohort (children; 29 cases, mean follow-up 3.3 years): no deaths; complications in 4 patients, all managed without sequelae; significant residual shunts after first procedure occurred in 17.2% but were closed successfully later; no recurrences reported (tabib2023longtermoutcomeof pages 2-4). - LCX-CAF transcatheter closure series (adult/predominantly adult, follow-up ~62 months): post-closure myocardial infarction 4.5% (1/22), recanalization 9.1% (2/22) (wei2024outcomesoftranscatheter pages 1-3).

8. Treatment

8.1 Current applications and real-world implementations

Transcatheter closure (TCC) is widely implemented for suitable anatomy (e.g., single narrow drainage site, accessible donor vessel), using coils and occluder devices (e.g., PDA occluder-type devices, vascular plugs). The 2023 cohort reported coils in 79.3% and other occluders less commonly (tabib2023longtermoutcomeof pages 1-2). The 2024 QFR cohort primarily used coils (47/48) (sang2024thefunctionalimpact pages 2-3). The 2024 LCX-CAF series used occluders deployed via transarterial approach or arteriovenous loop (wei2024outcomesoftranscatheter pages 1-3).

Surgery remains important for complex anatomy, giant aneurysms, multiple/diffuse fistulas, or when catheter closure is not feasible; however, detailed comparative outcome statistics were not available in the retrieved 2023–2024 texts beyond noting that TCC is “a feasible and effective alternative to surgical repair, with comparable outcomes in selected patients” (wei2024outcomesoftranscatheter pages 1-3).

8.2 Indications and expert opinion (from authoritative reviews)

The 2023 review emphasizes individualized decision-making and notes that “Both surgical and percutaneous options are available for symptomatic patients or those with complications, while management of asymptomatic CAF remains a viable alternative.” (kumar2023coronaryarteryfistula pages 1-2). It also reports that antibiotic prophylaxis is recommended once diagnosed (kumar2023coronaryarteryfistula pages 2-4).

8.3 Recent data highlights (2023–2024)

  • Functional impact / ischemia physiology: Medium CAFs demonstrated significant donor-vessel QFR improvement after closure, supporting closure when medium lesions are physiologically important (sang2024thefunctionalimpact pages 1-2).
  • Long-term interventional outcomes (single center): Minimal residual shunts can close spontaneously; major coronary injury/dissection/ischemia were not observed in a 29-patient cohort (tabib2023longtermoutcomeof pages 2-4).
  • LCX-CAF outcomes: Feasibility 77.3% (22/25); no procedural complications; MI 4.5% and recanalization 9.1% over ~5 years of follow-up (wei2024outcomesoftranscatheter pages 1-3).

8.4 Suggested MAXO terms (examples)

  • Transcatheter embolization/occlusion: MAXO:0000517 (Embolization therapy) (suggested)
  • Cardiac catheterization procedure: MAXO:0000506 (Cardiac catheterization) (suggested)
  • Surgical ligation/repair of fistula: MAXO:0000127 (Surgical procedure) / MAXO:0000004 (Surgical repair) (suggested)
  • Antiplatelet/anticoagulation therapy (post-closure): MAXO:0000473 (Anticoagulant therapy) / MAXO:0000515 (Antiplatelet therapy) (suggested)

9. Prevention

9.1 Primary prevention

For congenital CAF, primary prevention is not established in the retrieved evidence.

9.2 Secondary/tertiary prevention (complication prevention)

Evidence supports surveillance and anatomy-guided management to prevent ischemia, heart failure, and endocarditis complications (kumar2023coronaryarteryfistula pages 1-2, kumar2023coronaryarteryfistula pages 2-4). For acquired CAF, reducing iatrogenic injury risk during PCI/CABG and monitoring after chest radiation/MI/vasculitis is implicated but not quantified (kumar2023coronaryarteryfistula pages 1-2).

10. Other species / natural disease & model organisms

No evidence regarding naturally occurring CAF in non-human species, nor dedicated model organisms, was identified in the retrieved texts.

11. Data gaps and limitations of this evidence synthesis

  • Administrative/ontology identifiers (MONDO/MeSH/ICD/OMIM/Orphanet) were not available in the retrieved full texts.
  • The retrieved 2023–2024 sources did not report genetics/variant-level associations.
  • Differential diagnosis and standardized diagnostic criteria were not explicitly enumerated in the retrieved texts.
  • QoL instruments and population-level prospective natural history data were not found in the accessed set.

Appendix: Key quoted abstract/text statements (verbatim)

  • “Coronary artery fistula (CAF) is a false vascular channel; that is, a direct communication of the epicardial coronary artery with one of the four chambers or the major vessels of the heart or chest.” (kumar2023coronaryarteryfistula pages 1-2)
  • “CTCA has become the gold standard diagnostic evaluation tool for CAF because of the higher temporal and spatial resolution compared with other imaging modalities.” (kumar2023coronaryarteryfistula pages 2-4)
  • “Despite this, the diagnostic accuracy is still 35–50%.” (echocardiography accuracy statement) (kumar2023coronaryarteryfistula pages 2-4)
  • “Coronary artery fistulas (CAFs) are abnormal connections of the coronary arteries that bypass the myocardial capillary bed and terminate into chambers of the heart or major blood vessels.” (li2020coronaryarteryfistulas pages 1-2)
  • QFR study conclusion: “A small residual shunt has no significant impact on the effectiveness of CAFs occlusion in enhancing donor blood flow.” (sang2024thefunctionalimpact pages 1-2)

References

  1. (kumar2023coronaryarteryfistula pages 1-2): Rajesh Kumar, Jathinder Kumar, Cormac O’Connor, Ihsan Ullah, Benjamin Tyrell, Ian Pearson, Sajjad Matiullah, and Kevin Bainey. Coronary artery fistula: a diagnostic dilemma. Interventional Cardiology: Reviews, Research, Resources, Nov 2023. URL: https://doi.org/10.15420/icr.2022.34, doi:10.15420/icr.2022.34. This article has 31 citations.

  2. (li2020coronaryarteryfistulas pages 1-2): Ning Li, Peng Zhao, Dawei Wu, and Changhu Liang. Coronary artery fistulas detected with coronary ct angiography: a pictorial review of 73 cases. The British journal of radiology, 93:20190523, Apr 2020. URL: https://doi.org/10.1259/bjr.20190523, doi:10.1259/bjr.20190523. This article has 29 citations.

  3. (kumar2023coronaryarteryfistula pages 2-4): Rajesh Kumar, Jathinder Kumar, Cormac O’Connor, Ihsan Ullah, Benjamin Tyrell, Ian Pearson, Sajjad Matiullah, and Kevin Bainey. Coronary artery fistula: a diagnostic dilemma. Interventional Cardiology: Reviews, Research, Resources, Nov 2023. URL: https://doi.org/10.15420/icr.2022.34, doi:10.15420/icr.2022.34. This article has 31 citations.

  4. (tabib2023longtermoutcomeof pages 1-2): Avisa Tabib, Hojjat Mortezaeian, Mohammad Mahdavi, Yasaman Khalili, Nikolaus A. Haas, and Sepideh Mohammadhoseini. Long-term outcome of interventional approaches for treatment of coronary artery fistulas: a retrospective cohort study in a great referral center. The Egyptian Heart Journal, Mar 2023. URL: https://doi.org/10.1186/s43044-023-00339-4, doi:10.1186/s43044-023-00339-4. This article has 2 citations.

  5. (tabib2023longtermoutcomeof pages 2-4): Avisa Tabib, Hojjat Mortezaeian, Mohammad Mahdavi, Yasaman Khalili, Nikolaus A. Haas, and Sepideh Mohammadhoseini. Long-term outcome of interventional approaches for treatment of coronary artery fistulas: a retrospective cohort study in a great referral center. The Egyptian Heart Journal, Mar 2023. URL: https://doi.org/10.1186/s43044-023-00339-4, doi:10.1186/s43044-023-00339-4. This article has 2 citations.

  6. (sang2024thefunctionalimpact pages 3-5): Zhenchi Sang, Qingqi Ji, Huan Tong, Linghong Shen, Xiaolong Wang, and Ben He. The functional impact on donor vessel following transcatheter closure of coronary artery fistulas—a retrospective study using qfr analysis. Frontiers in Cardiovascular Medicine, Jul 2024. URL: https://doi.org/10.3389/fcvm.2024.1435025, doi:10.3389/fcvm.2024.1435025. This article has 1 citations and is from a peer-reviewed journal.

  7. (sang2024thefunctionalimpact pages 2-3): Zhenchi Sang, Qingqi Ji, Huan Tong, Linghong Shen, Xiaolong Wang, and Ben He. The functional impact on donor vessel following transcatheter closure of coronary artery fistulas—a retrospective study using qfr analysis. Frontiers in Cardiovascular Medicine, Jul 2024. URL: https://doi.org/10.3389/fcvm.2024.1435025, doi:10.3389/fcvm.2024.1435025. This article has 1 citations and is from a peer-reviewed journal.

  8. (sang2024thefunctionalimpact pages 1-2): Zhenchi Sang, Qingqi Ji, Huan Tong, Linghong Shen, Xiaolong Wang, and Ben He. The functional impact on donor vessel following transcatheter closure of coronary artery fistulas—a retrospective study using qfr analysis. Frontiers in Cardiovascular Medicine, Jul 2024. URL: https://doi.org/10.3389/fcvm.2024.1435025, doi:10.3389/fcvm.2024.1435025. This article has 1 citations and is from a peer-reviewed journal.

  9. (sang2024thefunctionalimpact pages 7-8): Zhenchi Sang, Qingqi Ji, Huan Tong, Linghong Shen, Xiaolong Wang, and Ben He. The functional impact on donor vessel following transcatheter closure of coronary artery fistulas—a retrospective study using qfr analysis. Frontiers in Cardiovascular Medicine, Jul 2024. URL: https://doi.org/10.3389/fcvm.2024.1435025, doi:10.3389/fcvm.2024.1435025. This article has 1 citations and is from a peer-reviewed journal.

  10. (wei2024outcomesoftranscatheter pages 1-3): Peijian Wei, Fang Fang, Fengwen Zhang, Yihang Li, Pengxu Kong, Shuyi Feng, Zhongying Xu, Liang Xu, Junyi Wan, Gejun Zhang, and Xiangbin Pan. Outcomes of transcatheter closure of congenital left circumflex coronary artery fistula. Circulation Journal, 88:1383-1390, Aug 2024. URL: https://doi.org/10.1253/circj.cj-23-0800, doi:10.1253/circj.cj-23-0800. This article has 4 citations and is from a peer-reviewed journal.

  11. (podolec2019presenceandcharacteristics pages 1-2): Jakub Podolec, Łukasz Wiewiórka, Zbigniew Siudak, Krzysztof Malinowski, Krzysztof Bartuś, Dariusz Dudek, Krzysztof Żmudka, and Jacek Legutko. Presence and characteristics of coronary artery fistulas among patients undergoing coronary angiography. Kardiologia Polska, 77:1034-1039, Nov 2019. URL: https://doi.org/10.33963/kp.14963, doi:10.33963/kp.14963. This article has 18 citations and is from a peer-reviewed journal.

  12. (podolec2019presenceandcharacteristics pages 2-3): Jakub Podolec, Łukasz Wiewiórka, Zbigniew Siudak, Krzysztof Malinowski, Krzysztof Bartuś, Dariusz Dudek, Krzysztof Żmudka, and Jacek Legutko. Presence and characteristics of coronary artery fistulas among patients undergoing coronary angiography. Kardiologia Polska, 77:1034-1039, Nov 2019. URL: https://doi.org/10.33963/kp.14963, doi:10.33963/kp.14963. This article has 18 citations and is from a peer-reviewed journal.

  13. (kumar2023coronaryarteryfistula media bbccd634): Rajesh Kumar, Jathinder Kumar, Cormac O’Connor, Ihsan Ullah, Benjamin Tyrell, Ian Pearson, Sajjad Matiullah, and Kevin Bainey. Coronary artery fistula: a diagnostic dilemma. Interventional Cardiology: Reviews, Research, Resources, Nov 2023. URL: https://doi.org/10.15420/icr.2022.34, doi:10.15420/icr.2022.34. This article has 31 citations.