A morphological study of dissecting aneurysm of aorta in old individuals over 50 years of age.
The authors have investigated the pathogenesis of dissecting aneurysms morphologically in 49 cases over 50 years of age, using 93 cases of other diseases in the same age group as control cases. All cases were autopsied at the Tokyo-to Medical Examiner Office. The dissecting aneurysms were divided into two types: one type occurred chiefly at the ascending aorta where atherosclerosis was missing or slight, and the other type chiefly at the descending aorta with severe atherosclerosis of the intima. In the former type, intimal tears were recognized in all cases and microscopically in the neighboring area of the cleft of aortic wall vacuolous large cyst without accumulation of metachromatic ground substance. Near the cyst, elastic lamellae were destroyed and the vasa vasorum was generally thickened, and multiple dissecting hemorrhages were observed. In the latter type, even when the intimal tears were not obvious, microscope revealed crumbled atheroma and bleeding in the intima or bleeding within the atheroma. The dissecting bleeding continued from it. Moreover, since enlargement of heart was observed in most cases, hypertension was thought to be an important factor among the predisposing factors in the pathogenesis of dissecting bleeding of the aorta.
D000367:Age Factors; D000368:Aged; D000784:Aortic Dissection / Q000473:pathology*; D001011:Aorta / Q000473:pathology; D001014:Aortic Aneurysm / Q000473:pathology*; D001161:Arteriosclerosis / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged