Mortality is high in untreated infants and only a few survive to an older age.
An asymptomatic 15 year old male was evaluated for an incidentally detected continuous murmur over the left third intercostal space parasternally. Clinical examination was otherwise unremarkable. The chest x-ray and electrocardiogram were normal. Colour doppler echocardiography revealed an anomalous LCA draining into the pulmonary artery with left to right shunting. Surgery was performed under cardiopulmonary bypass.