Prevalence and characteristics of coronary artery fistula in adults: coronary angiographic analysis of 18,106 patients.

Aim    Coronary artery fistula (CAF) is a rarely encountered anomaly that is characterized by an abnormal connection between a coronary artery and a cardiac chamber or a great thoracic vessel. Its incidence has not been precisely established due to the large number of undiagnosed cases and it shows heterogeneity in its anatomic configuration and clinical consequences. We aimed to assess the frequency, imaging findings, and clinical features of CAF among patients in our tertiary medical center.Material and methods    The angiographic data of 18,106 consecutive adult patients who underwent coronary angiography between January 2011 and June 2013 were retrospectively analyzed.Results    CAF was detected in 22 patients (0.14 %). Of these, 5 patients had bilateral fistulas (23 %). 65 % of the fistulas originated from the left anterior descending coronary artery,and 53 % drained into the pulmonary artery. The left ventricle and left atrium were the only drainage sites for left-sided coronary artery fistulas. One patient with a CAF presented with non-ST elevated myocardial infarction in the absence of an evident thrombosis.Conclusion    Unlike previous reports, bilateral CAFs were more commonly encountered in this study. Contrary to most of the data in the literature, more than half of the CAFs originated from the left anterior descending coronary artery and most drained into the pulmonary artery. Rare anatomic types of CAFs were also detected.