Management of Coronary Artery Fistulas

Definition and Epidemiology

Coronary artery fistulas (CAFs) have an incidence of 0.1% to 0.2% of all catheterized patients and represent the second most common coronary artery anomaly after anomalous coronary artery origins 1, 2
These fistulas typically arise from either the right coronary artery or left anterior descending artery, with drainage most commonly to the right atrium, right ventricle, or pulmonary artery 3, 4

Most patients with CAFs are asymptomatic, particularly in childhood, with increasing symptoms developing in adulthood 3, 4
Clinical manifestations can include thrombosis within the fistula, potentially causing myocardial infarction 3
Paroxysmal atrial fibrillation and ventricular arrhythmias can occur in patients with CAFs 3
Endarteritis is a potential complication of CAFs 2
Risk of rupture, particularly with increasing age and fistula size, is a concern in patients with CAFs 1, 2

A continuous murmur is often present and highly suggestive of CAF; its origin should be defined by imaging 1, 2
CT angiography or MRI is recommended for detailed anatomical evaluation of CAFs 1, 2
Transcatheter delineation of the CAF course and access to distal drainage should be performed in all patients with audible continuous murmur 1, 2

Large CAFs should be closed via transcatheter or surgical approach regardless of symptomatology 1, 2
Small to moderate CAFs with documented myocardial ischemia, arrhythmia, unexplained ventricular dysfunction or enlargement, or endarteritis should be closed via transcatheter or surgical approach 1, 2, 5
Symptomatic coronary artery fistulae require transcatheter occlusion 6, 7

Transcatheter closure is preferred for suitable anatomy due to less invasiveness, and can be performed with coils or other occluding devices 3, 4
Surgical intervention is indicated when transcatheter closure is not feasible or has failed, and should be performed by surgeons with training and expertise in congenital heart disease 1, 2

Patients with small, asymptomatic CAFs should have clinical follow-up with echocardiography every 3 to 5 years 1, 2
Patients with treated CAFs should have intermediate and long-term follow-up, as these patients may still have large, patulous epicardial conduits 5