Anomalous Origin of the Left Coronary Artery from the Pulmonary Trunk with Special Reference to the Occurrence of Mitral Insufficiency

Abstract

Nine cases of anomalous origin of the left coronary artery from the pulmonary trunk, involving patients ranging in age from 2 months to 7 years, have been reviewed. In six patients, mitral insufficiency was a prominent feature and, in three of these patients, mitral insufficiency presented the major problem, clinically. Of the five patients who died, necropsy was done in four. In each, healed infarction of the posterior papillary muscles of the left ventricle was demonstrated and, in two, the anterior papillary muscles were also involved. The clinical picture was that of an acyanotic patient with nonspecific respiratory complaints and retardation of growth. In five patients, there were symptoms (although a presenting complaint in only one) which are considered classic for this anomaly. These symptoms included episodes of pallor, dyspnea, and perspiration. Eight patients experienced cardiac failure in infancy and response to digitalis was effective in each. In this study, endocardial fibroelastosis, without associated cardiac malformations other than mitral insufficiency, presented difficulty in the differential diagnosis. The vectorcardiogram in the horizontal plane was most helpful in the diagnosis of anomalous origin of the left coronary from the pulmonary trunk. The QRS sÊ loop in the horizontal plane in this anomaly was oriented posteriorly to the left and its direction was clockwise, in contrast to the counterclockwise direction of the loop in endocardial fibroelastosis. Selective ascending aortography or selective right coronary arteriography established the diagnosis in seven cases.