Complete Interruption of the Aortic Arch.

A LOCALIZED NARROWING of the IAJL aorta at or distal to the ductus arteriosus (coaretation of the adult type) is one of the most comnlon congenital nmalformations of the great vessels. A narrowing of the aorta proximal to a patent ductus arteriosus (coaretation of the infantile type) is less commoni, while complete interruption of the aorta proximal to the ductus is quite rare, and interruption distal to the ductus has not been recorded. Interruption of the aortic arch, also termed absence, interruption, or atresia of the isthmus of the aorta, functionally corresponds to the most severe form of the infantile type of coaretation. The adult type of coaretation of the aorta is relatively easily recognized by clinical neans and the results of surgical treatment are, in general, good. The diagnosis of complete interruption of the aorta, on the other hand, has rarely been made before death or exploratory operation and, although it too is amenable to surgical correction or palliation, few attempts at operative treatment have been made. Three patients with complete interruption of the aortic arch have been studied at the National Heart Institute. In the present report the clinical, hemodynamie, angiographic, and pathologic findings in these patients are described and the information derived from 52 previously reported patients is reviewed. Embryology A pathologic classification used by Celoria and Pattonll of aortic arch interruption, based on the sites of origin of the branches of the aortic arch, has been found applicable in the present study. The embryologic mechanisms