[Hemodynamic mechanisms of the superior and inferior vena cava flow changes following experimental myocardial ischemia].

In acute experiments in anesthetized cats myocardial left ventricular ischemia caused the decreasing of the arterial pressure, cardiac output, superior and inferior vena cava flow and venous return. The diminishing of the superior vena cava flow was caused by the decreasing of the cardiac output, increasing of the vascular resistance and decreasing of the blood flow in the region of the brachiocephalica artery. The inferior vena cava flow decreased following the diminishing of the cardiac output and abdominal aorta blood flow, while vascular resistance in this region did not change. In acute experiments in anesthetized rabbits following myocardial ischemia after the blockade of N-cholinoreceptors the superior and inferior vena cava flow decreased in the same level as in control animals. Following myocardial ischemia after the blockade of α-adrenoreceptors the superior and inferior vena cava flow decreased more significant, than in control animals.