Variations with age and serum cholesterol level in the topographic distribution of macroscopic aortic atherosclerotic lesions as assessed by image analysis methods

Abstract

The topographic distribution of macroscopic atherosclerotic lesions in the aorta was studied by image analysis of aortas taken at autopsy from 155 males aged 10 to 54 yr. In both the thoracic and abdominal aorta, fatty streaks (FS) appear before raised lesions (RL) affecting preferential areas located longitudinally along the intercostal ostia, at the aorta bifurcation, and surrounding the points of origin of branches of the abdominal aorta. Later RL appear in the same areas of the aortic intima affected by FS at younger ages. As for the effect of serum total cholesterol (TC) in the progression of atherosclerosis, the prevalent involvement areas by FS and RL were similarly distributed as indicated by our analyses. However, areas showing frequent occurrence of FS and RL in each aortic segment were distributed more extensively at identical areas in the higher serum TC groups than in the lower TC level group. Thus, it can be concluded that FS are the precursor lesions of RL in the aorta and that the serum TC promotes the progression of atherosclerosis.