Structural and metabolic changes in cardiac conducting system during massive pulmonary embolism.

We studied structural and metabolic changes in ventricular conducting cardiomyocytes during the acute phase of massive pulmonary embolism complicated or uncomplicated by cardiac insufficiency. During massive pulmonary embolism without cardiac insufficiency, glycolysis in conducting cardiomyocytes of both ventricles was activated, and its contribution to energy formation increased. Massive pulmonary embolism complicated by cardiac insufficiency was accompanied by inhibition of glycolytic enzymes and damages to conducting cardiomyocytes of the left and right ventricles. Our findings indicate that the development of cardiac insufficiency during the acute phase of massive pulmonary embolism provides structural and morphological basis for impairment of electrophysiological properties of the myocardium.