ALCAPA with normal left coronary artery flow pattern and demonstration of flow reversal on oxygen inhalation

Anomalous left coronary artery from pulmonary artery (ALCAPA) is an uncommon congenital heart defect. In most of the cases it presents in early infancy when the pulmonary artery pressure decreases and pulmonary vascular resistance falls. ECG and chest X-ray help in diagnosing this condition, however, transthoracic echocardiography confirms the diagnosis in most of the cases. 2D echo shows origin of left coronary artery from pulmonary artery and on colour Doppler retrograde flow is seen in left main, left anterior descending and left circumflex coronary arteries. Antegrade flow in the left coronary artery has been described in past when ALCAPA was associated with a shunt lesion like a ventricular septal defect (VSD) or a patent ductus arteriosus (PDA). We are reporting a case of ALCAPA with severe left ventricular (LV) dysfunction with normal flow pattern in left coronary artery with no associated cardiac anomaly and demonstration of retrograde flow on oxygen inhalation.