Anomalous left subclavian artery from the pulmonary artery in a neonate.

The presence of an isolated left subclavian artery arising from the pulmonary artery in a patient with d-transposition of the great arteries is exceedingly rare. Prior to undertaking repair of this congenital cardiac anomaly, identification of an isolated left subclavian artery originating from the pulmonary artery is imperative in order to plan the appropriate intervention to prevent the development of subclavian artery steal or vertebrobasilar insufficiency. We describe the case of a 5 day-old girl in whom an isolated left subclavian artery arising from the pulmonary artery was detected after surgical entry for repair of transposition of the great arteries.