Coronary artery fistulas emptying into left heart chambers

We present three cases of coronary artery fistulas entering into the left heart chambers. Coronary arteriography in one showed aneurysmal dilatation of the main left coronary artery and a fistulous communication with a large left atrium. Exploration during repair revealed an anomalous branch of the left circumflex emptying into the left atrium. In the second case the proximal left circumflex gave rise to a branch supplying a hemangioma which emptied into the left atrium. Coronary arteriograms of the third patient showed an enlarged left anterior descending artery with an anomalous branch emptying into the left ventricle. Shunt flow was estimated with hydrogen as a tracer in the last two cases and was two thirds and one third of the left coronary inflow, respectively. Review of the literature shows 32 previously reported cases of a fistula draining into the left side of the heart.