Complete Transposition of the Great Vessels

Abstract

This paper is based on a study of specimens of the heart that were obtained in 60 cases of complete transposition of the great vessels. The external relationship of the aorta and pulmonary trunk usually differed from the classic description of the aorta lying directly anterior to the pulmonary trunk (type III). This relationship was present in only two of the 60 cases. In 39 cases, the relationship of the great vessels was oblique (type I). In 19 of the 60 cases, the relationship of the great vessels was side-to-side (type II). There were two main patterns of origin of the coronary arteries. One had a tendency to be associated with the oblique (type I) relationship of the great vessels, which was most common; the other had a tendency to be associated with the side-to-side (type II) relationship of the great vessels, which was the second most common type. A ventricular septal defect was present in 22 (37 per cent) of the 60 cases. The anatomic characteristics of these defects were the same as occur in cases of an isolated defect in the ventricular septum. It was of particular interest that a left ventricular-right atrial communication was observed in three cases. Miscellaneous conditions observed include congenital obstruction of the aortic arch (eight cases), a right aortic arch in association with a ventricular septal defect and pulmonary stenosis (two cases), and juxtaposition of the atrial appendages (two cases). The atrioventricular valves resembled the homolateral valves of normal hearts. An Ebstein-like malformation of the mitral valve was present in one case.