[Histopathological findings of coronary arteries in cases with acute coronary syndromes]

Abstract

A histopathological study of coronary arteries in patients with acute coronary syndromes was carried out. The results of this study are as follows: 1. A high incidence of thrombus formation, corresponding to the site of the infarction, was observed in cases with acute myocardial infarction. 2. Coronary thrombi containing plaque components such as foam cells, cholesterol clefts, and fractured intimal collagen fibers were detected. 3. Patients who succumbed suddenly after coronary attack had ruptured atheromatous plaque only, but not a thrombus. As these patients showed severe stenosis with recanalization in 2 of the 3 main coronary arteries, the rupture of the plaque caused significant occlusion of the remaining coronary artery. 4. Increase of intra-plaque pressure resulting from a honeycomb-like accumulation of foam cells, cholesterin clefts, and blood infiltration from lumen to plaque through the injured endothelial cells is the cause of rupture of the atheromatous plaque. This rupture into the lumen might precede, and be responsible for formation of the thrombus and onset of acute coronary syndromes.