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Congenital coronary artery fistula — Clinical Guidelines

Overview

Congenital coronary artery fistulas (CPAFs) are rare vascular malformations connecting coronary arteries to the pulmonary artery or other systemic veins, often asymptomatic but potentially leading to complications like heart failure or arrhythmias. 1 2 4

Diagnosis

Transthoracic echocardiography (TTE): Useful for detecting characteristic flow patterns, such as late diastolic flow indicative of fistulous connections. 5

Contrast echocardiography: Enhances visualization of fistulous connections. 2

Cardiac catheterization: Gold standard for definitive diagnosis and assessment of shunt dynamics. 2 5

Pulmonary angiography: Identifies fistulous connections, especially when other imaging modalities are inconclusive. 4

Management

Endovascular embolization:

- Antegrade approach: Preferred in younger patients due to ease and reduced radiation exposure. 1 - Retrograde approach: More challenging but ensures complete closure in a single procedure, particularly useful for single dominant feeders. 1 3

Surgical closure: Recommended for symptomatic patients with isolated CPAF, showing significant improvement post-surgery. 6

Special Populations

Pediatrics: Transcatheter coil embolization is safe and effective, often using a retrograde coaxial delivery system. 3

Symptomatic Patients: Surgical closure is advised for symptomatic individuals to achieve clinical improvement. 6

Key Recommendations

Consider patient age and fistula configuration when choosing embolization approach: Antegrade for younger patients, retrograde for definitive closure in complex cases. (Evidence: Moderate 1)

Endovascular embolization is effective for closure in pediatric patients: Retrograde approach can be particularly successful in infants and young children. (Evidence: Weak 3)

Surgical closure should be considered for symptomatic patients with isolated CPAF: To ensure significant clinical improvement. (Evidence: Moderate 6)

References

1 Montag MJ, Möhlenkamp S, von Dohna M. Strategic approach to embolization of coronary to pulmonary artery fistulas: a technical note. Acta radiologica (Stockholm, Sweden : 1987) 2025. link 2 Wu W, Li J, Wang W, Lin Q. Transthoracic echocardiography for diagnosis of right pulmonary artery to left atrial fistula. Echocardiography (Mount Kisco, N.Y.) 2013. link 3 Kung GC, Moore P, McElhinney DB, Teitel DF. Retrograde transcatheter coil embolization of congenital coronary artery fistulas in infants and young children. Pediatric cardiology 2003. link 4 Aydoğdu S, Ozdemir M, Diker E, Korkmaz S, Kütük E, Göksel S. Fistulous connection between the left pulmonary artery and the innominate vein. Catheterization and cardiovascular diagnosis 1996. link1097-0304(199609)39:1<80::AID-CCD17>3.0.CO;2-S) 5 Said S. Doppler echocardiographic findings in coronary-pulmonary fistula. International journal of cardiology 1989. link90227-1) 6 Bogers AJ, Quaegebeur JM, Huysmans HA. Early and late results of surgical treatment of congenital coronary artery fistula. Thorax 1987. link

Congenital coronary artery fistula