Calculation of mass of necrosis developing in the necrotic period of a myocardial infarct

: A method is proposed for the estimation of intravital necrotic weight in myocardial infarction (MI) that permits the assessment of necrotic weight at any hour of the necrotic MI stage. It is based on a mathematical model of nonlinear diffusion of a biochemical enzyme into the blood from necrotized tissue, followed by nonlinear enzyme washing out of the blood, with an adjustment for enzyme deactivation. The estimated values showed good correlation to autopsy findings. A formula for necrotic weight determination at any time of the necrotic MI stage is derived on the basis of variation in blood MB CPK level. Mean necrotic weight increment rate was 3 +/- 0.1 g/hour in the necrotic stage of myocardial infarction.