Ruptured and Stable Atherosclerotic Lesions A Structural Analysis With Histopathological Correlation

Background. Although rupture of an atherosclerotic plaque is considered to be the cause of most acute coronary syndromes, the mechanism of plaque rupture is controversial. Methods and Results. To test the hypothesis that plaque rupture occurs at sites of high circumferential stress in the diseased vessel, the distribution of stress was analyzed in 24 coronary artery lesions. Histological specimens from 12 coronary artery lesions that caused lethal myocardial infarction were compared with those from 12 stable control lesions. A finite element model was used to calculate the stress distributions at a mean intraluminal pressure of 110 mm Hg. The maximum circumferential stress in plaques that ruptured was significantly higher than maximum stress in stable specimens (4,091± 1,199