I. Without Pulmonary Stenosis

AMONG the congenital malformations in t& which an abnormal relationship exists between the aorta and pulmonary trunk is that in which both of these vessels arise from the right ventricle. The only outlet for the left ventricle is a ventricular septal defect. Right ventricular infundibular stenosis may or may not be associated. These cases apparently are extremely rare,1-3 and only a few have been reported in the last 25 years.4-7 A few cases were documented in the last century.1 3 Many terms have been used for this malformation, including " partial transposition, 2 "double-outlet right ventricle, ' '7 and "origin of both great vessels from the right ventricle. ' '8 Witham,7 in 1957, summarized six cases reported in detail in the literature and added four cases. He divided these cases into two groups and called them the "Fallot type " and the " Eisenmenger type," depending on the presence or absence of pulmonary stenosis. One of the patients in his study was seen at the Mayo Clinic.9 This case was not included in the present analysis because additional multiple intracardiac malformations were present, and it appeared to us that different embryologic as well as hemodynamic problems were involved. In a study of the pathologic and clinical material from the Mayo Clinic, we found 14 cases in which both great vessels originated from the right ventricle. Three main categories of this malformation occurred as follows: (1) without pulmonary stenosis (eight cases); (2) with pulmonary stenosis