An anatomopathologic study of membranous septum aneurysms and significanceof their surgical treatment

The purpose of the study: We analyzed 14 patients with menbranous septal an eurysms presenting with a left-to-right communication, by comparing the ang iographic, operative and pathological findings. We decided to use medical t reatment on two patients and operated on the rest (12 cases), Basic methods: The mean age of the patients was 19 +/- 9 yr; nine were fema le, five were male. Cine-angiography of all patients revealed a saccular ab normality protruding into the right ventricle at the uppermost part of the interventricular septum, just below the aortic valve. The sac had the appea rance of a glove finger, a cauliflower, a diverticulum, or it was dome-shap ed on angiography, Principal findings: Perioperative exploration revealed a perforated true an eurysmal sac in seven patients. In three patients, the perimembranous tissu es were severely fibrotic, thickened or had more than one perforation. Two patients had a defect under the septal leaflet of the tricuspid valve at th e postero-inferior part of the septum, hidden between the chordae of the va lve. Conclusions: Defining the membranous septal abnormalities clearly is not al ways possible by cine-angiography, Echocardiography provides additional inf ormation, Pathological examination of the resected specimens showed almost total loss of elastic fibers and extensive accumulation of mucopolysacchari des. (C) 2000 The International Society for Cardiovascular Surgery, Publish ed by Elsevier Science Ltd. All rights reserved.