Anomalous left coronary artery from the pulmonary artery with a large patent ductus arteriosus: aversion of a catastrophe.

We present an infant who had an anomalous left coronary artery arising from the pulmonary artery (ALCAPA) and a large patent ductus arteriosus (PDA), who was diagnosed before a potentially catastrophic closure of PDA. In the presence of normal left ventricular function and the absence of coronary artery collaterals, it is difficult to diagnose ALCAPA. A disproportionate degree of left ventricular dilation and severity of mitral valve regurgitation relative to the degree of PDA shunt, and echogenic papillary muscles on an echocardiogram should raise a suspicion of coronary artery anomalies. The infant underwent surgical ligation of PDA with translocation of coronary arteries and had an uneventful recovery.