Four patients are described with an anomalous origin of the left coronary artery from the pulmonary artery. Three were treated by ligation of the abnormal left coronary artery at its anomalous origin; one of them died during surgery. One patient was treated with reimplantation of the left coronary artery into the aorta. Of the survivors 2 are in normal health, but 1 developed aortic valve incompetence after reimplantation of the left coronary artery into the aorta and 1 had persistent left ventricular wall motion abnormalities and developed mitral valve prolapse. The third survivor has impaired health with diffuse left ventricular wall motion abnormality. Careful follow-up after surgery for an anomalous left coronary artery arising from the pulmonary artery is necessary for secondary prevention of problems due to incomplete recovery of myocardium or problems as a consequence of surgical therapy.