AbstractA 3-year-old patient is described with an unusual form of co-arctation due to hypoplasia of the
transverse arch and fibromuscular dysplasia involving a long segment of the thoracic aorta. Surgical repair required resection of the aorta from the distal transverse arch to the mid-descending thoracic aorta, and replacement with a 16-mm Dacron interposition graft. This case demonstrates the importance of preoperative evaluation of the entire aorta in the presence of co-arctation due to fibromuscular dysplasia.