Anomalous origin of the left coronary artery from the pulmonary artery: A clinical spectrum

Five cases of an anomalous left coronary artery originating from the pulmonary artery have been presented. These illustrate different phases in the clinical spectrum of this anomaly. Two patients who presented with congestive failure and classic signs of myocardial infarction in early infancy underwent surgical ligation of the anomalous vessel. One survived and one died postoperatively, possibly with secondary residual mitral insufficiency as a contributory factor. Congestive failure and a clinical picture of mitral insufficiency developed in one other child at 1 year of age, and she died 10 months later with unremitting failure. Two children who were in failure in infancy, 1 with evidence of myocardial ischemia, have had a benign clinical course since that time. The clinical course and appropriate management of a patient would appear to depend upon the degree of development of the coronary collateral circulation. Some of the factors influencing the adequacy of these collateral vessels are postulated, including the presence of collateral channels at birth and the stimulation of new vessels by ischemia as the pulmonary arterial pressure falls. In those patients in whom the collateral circulation is adequate enough to allow survival, the clinical picture may be dominated by mitral regurgitation resulting from endocardial fibrosis with dilatation of the mitral valve ring.