The irreversible ischaemic lesion of human myocardium. Comparison with the experimental animal model

The autolytic ultrastructural changes of the human myocardium were studied in 25 specimens taken 30 min to 18 h post mortem. Damage to the mitochondrial membranes and the appearance of mitochondrial armorphous densities characterized the irreversible lesions of the autolytic myocardium. The development of these changes was observed in consecutive samples. At 30 min, few small densities were noticed inconsistently, and they progressively increased in size and number over the next 90 min. The development of these changes was unrelated to the cause of death. Comparison of the ischaemic heart lesions of animals with those of humans shows a similarity of the mitochondrial amorphous densities. The best analogy was found to exist between the autolytic changes of the human myocardium and the irreversible ischaemic heart lesions of dogs.