Background: The existing data on the morphological substrate of out-of-hospital sudden death due to ischemic (coronary) heart disease (IHD) and its relationship to other acute coronary syndromes are not sufficient and even controversial.
Material and methods: We analyzed clinical and pathological data from 170 men who died suddenly (within 6 h) of IHD out of hospital, as well as 54 men who died in hospital a documented acute myocardial infarction (AMI).
Results and conclusions: Majority (92,9%) of out-of-hospital sudden coronary deaths were due to AMI and 7,1%t - due to disseminated myocardial micronecroses. Death occurred mostly at early stages of AMI, and predominantly in the presence of morphological signs of acute left ventricular failure (alveolar pulmonary edema). Ruptures of atherosclerotic plaques or endothelial erosions with the intraplaque and superimposed luminal thrombosis were found in 88,8% of AMI cases. In 73,6% of cases plaque ruptures or erosions were located in 75% or greater stenoses mostly in proximal segments of coronary arteries. Acute coronary artery pathology could be identified by examination of serial histological sections, while early irreversible ischemic myocardial injury (early infarction) was detected by light and polarized light microscopy of histotopogrammes of the whole myocardium with due consideration of the complex of signs of cardiomyocyte alteration as well as early inflammatory reaction.