Effects of coronary heart disease risk factors on atherosclerosis of selected regions of the aorta and right coronary artery

We examined topographic distributions of atherosclerosis and their relation to risk factors for adult coronary heart disease in right coronary arterie s and abdominal aortas of more than 2000 autopsied persons 15 through 34 ye ars of age. We digitized images of Sudan IV-stained fatty streaks and of ma nually outlined raised lesions and computed the percent surface area involv ed, by each lesion in each of 6 regions of each artery. In abdominal aortas of 15- to 24-year-old persons, fatty streaks involve an elongated oval are a on the dorsolateral intimal surface and another oval area in the middle t hird of the ventral surface. Raised lesions in 25- to 34-year-old persons i nvolve an oval area in the distal third of the dorsolateral intimal surface . Tn other areas of the abdominal aortas of older persons, fatty streaks oc cur but raised lesions are rare. In the right coronary arteries of 15- to 2 4-year-old persons, fatty streaks are most frequent on the myocardial aspec t of the first 2 cm. Raised lesions follow a similar pattern in 25- to 34-y ear-old persons, High non-HDL cholesterol and low HDL cholesterol concentra tions are associated with more extensive fatty streaks and raised lesions i n, all regions of both arteries. Smoking is associated with more extensive fatty streaks and raised lesions of the abdominal aorta, particularly in th e dorsolateral region of the distal third of the abdominal aorta. Hypertens ion is not associated with fatty streaks in whites or blacks but is associa ted with more extensive raised lesions in blacks. Risk factor effects on ar terial regions that are vulnerable to lesions are approximate to 25% greate r than risk. factor effects assessed over entire arterial segments. These r isk factor effects on vulnerable sites emphasize the need for risk factor c ontrol during adolescence and young adulthood to prevent or delay the progr ession of atherosclerosis.