Role of Variations li Pilmoiary and Cardiac Hemodyiamics li the Reduction of the Venous Return during Experimental Ischemia of the Left Ventricular Myocardium

摘要

During left-ventricular myocardial ischemia, the decrease in the venous return is determined by reduction of cardiac output, which results from heart rate deceleration and decrease in left-ventricular stroke volume. The latter is related to a decrease in myocardial contractility and blood storage in the pulmonary circuit. Blood accumulation in the lungs is not observed during stimulation of the vagus nerve or treatment with propranolol (against the background of the same values of the negative chronotropic and inotropic effects as during myocardial ischemia). The left-ventricular stroke volume increases, while the cardiac output and venous return decrease to a lesser extent under these conditions.