EFFECT OF AGE, RACE, BODY-SURFACE AREA, HEART-WEIGHT AND ATHEROSCLEROSIS ON CORONARY-ARTERY DIMENSIONS IN YOUNG MALES

Compensatory arterial enlargement in response to atherosclerosis has b een demonstrated for the left main coronary artery. Only limited data is available on the interaction of patient characteristics and atheros clerosis with coronary artery dimensions. The purpose of the present s tudy was to evaluate the influence of age, race, body habitus, heart w eight and atherosclerosis on coronary artery dimensions of young males . Hearts from 137 young men (age 32 +/- 8 years; 78 black, 59 white) w ith unnatural deaths (homicide, suicide, accident, drug overdose) were perfusion-fixed, and histologic sections were obtained from the left main, proximal left anterior descending and left circumflex coronary a rteries. Computerized planimetry was performed on Movat stained sectio ns. Multiple regression analysis was used to evaluate the relative con tribution of plaque size, age, race, heart weight and body surface are a on coronary dimensions and compensatory enlargement in response to a therosclerosis. In the left anterior descending and left main coronary arteries, black race, body surface area and age were independent pred ictors of increased lumen area. In the left circumflex, age was a pred ictor of lumen area. Plaque area, black race and body surface area ind ependently predicted increased area enclosed by the internal elastic l amina area. There was compensatory enlargement of internal elastic lam ina with increasing plaque size in both races in the three arteries, b ut the percent luminal stenosis was greater in whites due to smaller a rtery size. Luminal narrowing did not develop until plaques occupied 3 0% of internal elastic lamina area. Among a population of young men wi th non-cardiac deaths, blacks have larger lumen and area enclosed by i nternal elastic lamina than whites. Age and body surface area are majo r determinants of lumen areas, and compensatory arterial enlargement w as seen in all examined arteries in the present study.