Repair of coarctation with persistent fifth arterial arch and atresia of the fourth aortic arch. Coarctation of the aorta with persistent fifth arterial arch and atresia of the fourth aortic arch between the left common carotid and left subclavian arteries was treated surgically in a two-month-old boy with transposition of the great arteries and double-outlet right ventricle. The aortic arch was repaired using side-to-side anastomosis of the left common carotid and left subclavian arteries, patch repair of the coarctated segment at the origin of the left subclavian artery, and ligation of the patent ductus arteriosus. Pulmonary arterial banding and balloon atrioseptostomy were performed for associated anomalies. 