Size of the Major Epicardial Coronary Arteries at Necropsy

Measurements at necropsy on 401 men indicate that variations in the original, presclerotic size of large epicardial coronary arteries may play a significant role in vulnerability to myocardial infarction and suggest that angiographic measurements of these vessels during life might detect susceptible individuals. Infarcts are seldom found in hearts with large coronary arteries (more than 7 sq cm external surface area per 100 gm heart weight) but are common when these arteries are small (less than 6 sq cm/100 gm). They are, in fact, seven times as frequent in the latter groups as in the former. Unlike large elastic arteries, the coronaries do not enlarge with advancing age. They increase only slightly in size in hypertrophied hearts and do not shrink in size in atrophic ones.