Congenital coronary artery fistula as a cause of angina pectoris.

Coronary arteriovenous fistula is an uncommon anomaly, representing an incidental finding in 0.1% to 0.2% of coronary angiograms. A 46-year-old man presented with a five-month history of palpitation and atypical stabbing chest pain on exertion and/or at rest. The electrocardiogram showed normal sinus rhythm, incomplete right bundle branch block with normal axis, and borderline left atrial abnormality. Echocardiography showed normal left ventricular function, mild left ventricular hypertrophy, moderate left atrial enlargement with mild mitral insufficiency, and moderate right atrial enlargement with mild-moderate tricuspid valve regurgitation. During exercise test, frequent ventricular ectopic beats were noted and the patient complained of atypical chest pain. Scintigraphy showed an ischemic defect in the inferior wall of the left ventricle. On coronary angiography, the right coronary artery and left anterior descending artery were normal, but the circumflex coronary artery was connected to the pulmonary artery through a congenital fistula. The patient refused any further intervention for fistula closure.