Three-hundred and thirty-five patients without left main stenosis or recent acute myocardial infarction underwent isolated aortocoronary bypass grafting during 1974 and 1975. The hospital mortality was 2 per cent for the four-year predicted survival is 94 per cent. Neither the preoperative presence or absence of a progressive or unstable angina pattern, the extent of coronary artery disease, nor the left ventricular ejection fraction predicted postoperative survival. None of the 25 patients whose ejection fraction was 0.30 or less died in the perioperative period, and no late deaths occurred in this subgroup until after 36 months of follow-up, giving a predicted four-year survival rate of 82 per cent. With only one exception, patients in this subgroup were operated on because of angina, which was unstable in three-quarters of them. We believe that this study shows that patients with a severely reduced ejection fraction should not be refused aortocoronary bypass grafting if symptoms of angina are severe and predominate over symptoms of heart failure.