[Ultrastructural analysis of myocardial condition during cardioplegic protection in heart valve prosthesis].

The article deals with the results of ultrastructural study of the myocardium at three stages of cardiosurgical operations: preischemic, ischemic, and during reoxygenation. A statistically significant difference was revealed in the condition of the cardiomyocyte organelles in each of these stages, and the degree of their intraoperative destruction was determined. It is concluded that ischemia of more than 90 minutes redoubles the progress of irreparable changes of the cardiomyocytes, particularly in patients with severe damage to the myocardium in the preischemic stage. The search for means of cardioprotection for these patients must be continued.