No abstract

SUMMARY A postmortem investigation was carried out of 19 heart specimens with transposition of the great arteries, ventricular septal defect, and congenital subvalvular pulmonary stenosis. Certain types of obstruction appeared to be closely related to other features of the hearts.In (Elliott et al., 1963;Shaher et al., 1967aShaher et al., , 1967b Daicoffet al., 1969;Rastelli et al, 1969;Fisher et al., 1970;Imamura et al., 1971;Quero-Jimenez et al., 1973;Shaher, 1973;Quero-Jimenez and Perez Martinez, 1974;Lancelin et al., 1975; QueroJimenez et al., 1975;Shrivastava et al., 1976; Buihlmeyer et al., 1977; Quero-Jimenez etcal., 1977;Van Praagh, 1977).If we exclude cases with other malformations, nonvalvular pulmonary stenosis in transposition of the great arteries with ventricular septal defect in the published reports is described in about 7 to 25 per cent of cases of transposition coming to necropsy (Lev et al., 1961;Elliott et al., 1963;Shaher et al., 1967b;Paul et al., 1968;Imamura et a!., 1971;Quero-Jimenez et al., 1973;Shaher, 1973;Van Praagh, 1977).Received for publication 1 August 1977 In our collection of 150 heart-lung specimens with d-transposition of the great arteries, there were 19 specimens with the combination transposition of the great arteries, ventricular septal defect, and clinical subvalvular pulmonary stenosis. In this paper a detailed description is given of the various structures, causing the subvalvular stenosis. DefinitionsTransposition of the great arteries is said to occur when the aorta arises from the morphologically right ventricle and the pulmonary trunk arises from the morphologically left ventricle. The infundibular septum is the structure interposing between two semilunar valves (Lev, 1972;Anderson et al., 1977), and in normal hearts it is incorporated on top of the ventricular septum; in the case of a malorientation of the infundibular septum a malalignment ventricular septal defect may result (Fig. la, 2a). The anterolateral muscle bundle of the left ventricle separates the anterior leaflet of the mitral valve from the anterior border of the left ventricle. It borders on the left sumilunar cusp and extends into the anterolateral wall of the left ventricle (Fig. lb, 2b) 494