[Anatomical and biochemical methods of determining the extent of myocardial infarct]

Twenty patients who died in the acute (necrotic) period of myocardial infarction were examined. The activity of MB creatinephosphate kinase was tested in all of them every 4 hours till the activity of the enzyme was normal. The boundaries of the lesion were determined. The boundaries of the lesion were determined during post-mortem examination by the method of nitroblue tetrazole stain, and the mass of the lesion was measured after excision of the necrotic myocardium. A high degree of correlation between the true mass of necrotized myocardium and the biochemical measure of necrosis was found (r = 0.698), which enabled the authors to derive a regression equation for determining the true mass of the affected myocardium (in g) in the live patient.