Congenital fistulas are the most common of the coronary arterial malformations and with the widespread use of selective coronary arteriography are being recognized with increasing frequency. Twenty-eight patients with congenital coronary fistulas have been evaluated at the Duke University Medical Center between 1960 and 1981. An additional 258 patients have previously been reported in the literature, making a total of 286 available for review. The right coronary artery is most commonly involved, and the fistulous communication is most often to the right ventricle, right atrium or pulmonary artery. Slightly more than half of the patients with coronary fistulas are symptomatic at the time the diagnosis is made. Surgical correction is strongly recommended to prevent the development of congestive heart failure, angina, subacute bacterial endocarditis, myocardial infarction, and pulmonary hypertension, as well as coronary aneurysm formation, with subsequent rupture or embolization. There were no operative or late deaths in the patients who underwent operations. Moreover, there have been no recurrent fistulas during a mean follow-up period of ten years. The risks of operative correction appear to be considerably less than the potential for development of serious and potentially fatal complications, even in asymptomatic patients.