Abstract

Three patients with angina pectoris are reported in whom occlusion of the left main coronary artery was found at coronary arteriography. In these three patients left ventricular function was well preserved. In all three the right coronary artery was dominant and there were prominent epicardial and septal collateral vessels to the territories normally supplied by the left anterior descending and circumflex arteries. It seems reasonable to suggest that this coronary artery anatomy and collateral vessel formation accounted for the preservation of the left ventricular myocardium in these patients.