Double outlet right ventricle {S,D,L} with subaortic ventricular septal defect and pulmonary stenosis. Report of six cases

The clinical, hemodynamic, angiocardiographic and pathologic findings are presented in an infrequent but surgically correctable type of double outlet right ventricle. This study is based on six cases, one with autopsy confirmation. In all, the viscera and atria were in situs solitus (S). A ventricular d-loop was present (D). There was l-malposition of the great arteries, the aorta being to the left of, and anterior to, the pulmonary artery (L). Hence, this anomaly may conveniently be represented as double outlet right ventricle {S,D,L}. The ventricular septal defect was subaortic because the aorta was anterior and leftward, adjacent to the ventricular septum. A bilateral conus was present beneath both the aortic and pulmonary valves, preventing any semilunar-atrioventricular fibrous continuity. The subpulmonary conus was poorly expanded, resulting in pulmonary infundibular and valvular (annular) stenosis. The clinical features were those of cyanosis, clubbing and accentuation of the second heart sound in the pulmonary area (related to aortic valve closure). There was a systolic ejection murmur along the upper left sternal border, related to pulmonary outflow tract stenosis. Selective right and left ventricular angiocardiography was diagnostic. Relatively early surgical correction is suggested to minimize the progression of pulmonary infundibular stenosis and to avoid acquired atresia. In this malformation, pulmonary outflow tract reconstruction is more difficult than in tetralogy of Fallot because of the rather posterior location of the pulmonary outflow tract, and because the right coronary artery crosses the stenotic pulmonary outflow tract in front of the pulmonary valve.