[Pulmonary artery stenosis with an intact interventricular septum].

15 hearts with pulmonary artery stenosis with an intact interventricular septum (PAS with IIVS) were studied morphologically and morphometrically. The results were evaluated separately according to the type of the defect: with a noncomplicated valvular stenosis of pulmonary artery (PA); with a combined valvular and infundibular stenosis of PA. Every of these types of PAS with IIVS has characteristic features of morphological structure and all possess common anatomical signs: constriction at one of the levels of circulation from the right ventricle to the lesser circulation, normal geometric structure of the cone and myocardial hypertrophy of the right ventricle. Leading cause of the obstruction of the right ventricle effluent part, regardless of the PAS with IIVS type, is a hypertrophy of the supraventricular crest and its parietal projection. As distinct from the defects on the conus-truncus, complex of PAS with IIVS is characterized by a normal spatial orientation of the supraventricular crest.