Different morphological types of myocardial cell death in man.

The evolutive histological stages, the frequency, and the eventual association of the different types of myocardial cell death have been studied in the following human material: acute infarction, sudden "coronary" death, accidental death, pheochromocytoma, transplanted hearts, "stone" heart syndrome, thrombotic thrombocytopenic purpura, and alcoholic cardiomyopathy. Three distinct main histological types of myocardial cell death are recognizable: Coagulation necrosis, the fundamental lesion in infarcts in which the myocardial cell loses its capability to contract and dies in an atonic state with overdistension due to the intraventricular pressure. No early myofibrillar damage is seen. Coagulative myocytolysis, found in all the present cases, always seen in the outer zone of an early infarct and in the surrounding normal myocardium at any stage of the repair process in most of the acute infarcts and in most cases of sudden death. The myocardial cell dies in a hypercontracted state, with early myofibrillar rhexis, and anomalous irregular cross-band formations. This tetanic death is similar to that seen in pheochromocytoma and in experimental catecholamine-induced necrosis. Colliquative myocytolysis, in which edematous vacuolization with dissolution of myofibrils is the main early finding, without hypercontraction, anomalous bands, and myofibrillar rhexis. This pattern, likely related to the low-output syndrome, was often seen in the preserved subendocardial and perivascular muscle fibers of acute infarct cases, in some transplanted hearts, and in all the alcoholic hearts. The different clear-cut morphological patterns of these three types of myocardial necrosis suggest a different pathogenesis and that different pathogenetic mechanisms may act in the same disease.