Anomalous Origin of the Left Coronary Artery: The Physiologic Defect and Suggested Surgical Treatment

The majority of infants born with an anomalous origin of the left coronary artery from the pulmonary artery die within the first year of life. This malformation produces a clinical picture of episodes of sweating, cyanosis and pallor usually following feeding. Associated findings are gross cardiac enlargement and electrocardiographic evidence of myocardial ischemia. Perfusion studies at necropsy indicate that extensive anastomoses allow free passage of blood from the normal right coronary artery to the left. There now appears evidence that flow through the anomalous left coronary artery is into the pulmonary artery rather than away from it. Thus although there is oxygenated blood in the left coronary artery, it does not reach the myocardium but passes instead to the low-resistance circuit of the pulmonary artery. Ligation of the aberrant vessel at its origin would prevent retrograde flow and allow perfusion of the left ventricle by blood supplied through the anastomoses from the right coronary artery. This would in effect convert the anomaly into that of a single coronary artery arising from the aorta, which situation is usually compatible with a normal life expectancy. Preliminary experience with this suggested surgical treatment appears encouraging in one of the cases reported.