[Changes in the ultrastructure of the myocardium after fibrillation and in the process of autolysis].

Ultrastructure of the myocardium in the experiment was studied just after the heart ventricular fibrillation and 3 h after the animal death; the results were compared to those obtained by studying ultrastructure of human myocardium in patients dying from myocardial infarction complicated by ventricular fibrillation. The similarity of ultrastructural and autolytic changes was revealed in both series of observation. Overcontraction of myofibrils and redistribution of the mitochondria in cardiomyocytes, increase of the sarcoplasmic reticulum vesiculation, oedema of sarcoplasm, structural alterations of intercalative discs, later appearance of the symptoms of the irreversibility of lesions in the mitochondria and early penetration of colloidal lanthanum particles in rigor cells may serve ultrastructural diagnostic symptom of ventricular fibrillation. A better preservation of Purkinje's cells as compared to the contractile cardiomyocytes is also demonstrated.