無症候若年者の冠動脈病変について

Abstract

Microfocusing postmortem coronary angiography was used to detect early atherosclerotic lesions in young people with no known risk factors. Following isolation and saline washing, coronary artery specimens were placed on a special radiolucent board, which could be rotated along the long axis so that mild eccentric stenosis could be identified. Angiography was performed with microfocusing image using radiopaque Barium. Ring sections were obtained at stenotic sites and compared with the angiographic findings. Using this method, we were able to see trivial eccentric stenosis not normally observed during macrographic postmortem angiography or premortem coronary angiograms.One hundred twenty-one autopsy cases were studied. Cases with evidence of cardiovascular disease (chest pain, palpitation, hypertension, EKG abnormalities, cardiomegaly on chest X-Ray, etc.), diabetes mellitus, or hyperlipidemia were eliminated from this study.The cases were divided into two groups: 68 cases (Group A) were examined macro-and microscopically after the coronary arteries were cut open and fixed. 53 cases (Group B) were examined by the microfocusing method without opening the lumen of the coronary arteries.In group A, 27 cases (39.7%) had at least one significant atherosclerotic lesion. In group B, 42 cases (79.2%) had visible stenosis by angiography. In group B, 23 cases (43.4%) showed more than 50% stenosis, while 19 cases (35.8%) had lesions with less than 50% stenosis, including very mild eccentric stenosis that might not be detected by macrographic methods. In both groups the left anterior descending artery (LAD) had the highest incidence of stenosis and most of the cases with two or three vessel disease had at least one LAD lesion.The degree of stenosis on angiography was compatible with findings on ring sections. Histologically, severe stenosis was mostly associated with duplication of the internal elastic lamina, foam cell formation, and core necrosis. On the other hand, mild eccentric stenosis was mainly associated with focal intimal thickening without changes in the internal elastic lamina or foam cell formation. Cardiac weight, interventricular septum thickness, anterior and posterior ventricular wall thickness, and degree of obesity showed no correlation with incidence and severity of coronary atherosclerosis.Stratifying by race and sex, black males had significantly higher incidence and severity of coronary atherosclerosis than other groups. No positive correlation could be seen between severity of coronary stenosis and aortic atherosclerosis.