Restrictive tissue in the area of perimembranous ventricular septal defect. Cross-sectional and Doppler echocardiographic study.

This study using pulsed and continuous wave Doppler echocardiography was designed to achieve a cross-sectional echocardiographic categorization of the fibrous tissues in the environs of perimembranous ventricular septal defects, to determine the mechanism involved in its formation and for qualitative and quantitative evaluation of the anomalies associated with the entity. A total of 67 patients was studied, 23 presented cross-sectional echocardiographic evidence of perimembranous ventricular septal defect in isolation, 12 associated with tissue 'tags' and 32 combined with 'restrictive' tissue in the area of the defect. Four echocardiographic features of the 'restrictive' tissue were observed. In 23 of these 32 patients, it was possible to identify the exact anatomic origin of the 'restrictive' tissue (in seven complete and, in 15, partial involvement of the septal leaflet of the tricuspid valve; in one, prolapse of the aortic valve with a partial involvement of the tricuspid septal leaflet) while in nine the origin remained undetermined. In 20, the 'restrictive' tissue simultaneously protruded into the right atrium and ventricle; only in 12 did it extend exclusively into the right ventricle. Tricuspid insufficiency was detected by pulsed Doppler in 78% of the patients with 'restrictive' tissue and in 23% of the remaining patients. Tricuspid incompetence was severe in only two patients of the first group. Three patients with 'restrictive' tissue (9%) had obstruction to the outlet of the right ventricle and four (13%) patients presented aortic insufficiency. Five patients (16%) with 'restrictive' tissue closing the defect did not present pulsed Doppler evidence of a shunt at the ventricular level.(ABSTRACT TRUNCATED AT 250 WORDS)