[Morphologic changes in the myocardium outside the zone of an experimental infarct]

By means of histological and electron-microscopic methods of investigation it was established that in the areas of the myocardium remote from the zone of the ligated coronary artery at early periods of the experiment there were noted impairment of the circulation and also dystrophic and necrobiotic changes in myocytes. Therefore the extra-infarction regions of the myocardium may not be considered as intact. An important role in the development of changes in the contractile elements of the myocardium was played by impairment of the circulation in the areas of the cardiac muscle remote from infarction, their acute functional overloading and also activation of the sympathoadrenal system.