The Contribution of Blood Momentum to Left Ventricular Ejection in the Dog
The Contribution of Blood Momentum to Left Ventricular Ejection in the Dog
复制标题
血液动量对狗左心室射血的贡献
作者：
M. Noble
在5只清醒犬和2只麻醉犬上，用高保真微压计测量了左心室与升主动脉之间的压力梯度。左心室压力在射血期的前30%至50%超过主动脉压力。在射血期的剩余时间内，主动脉压超过左心室压。这些差异的幅度从5到20毫米汞柱不等。在收缩晚期的这一发现意味着此时血液在其自身的动量下流出心室，并且主动脉是心室的压力源。五只狗的升主动脉突然闭塞，以验证这一假设。当射血期的最后三分之一发生阻塞时，左心室压力突然下降，显然证实了动量假说。
In five conscious dogs and two anesthetized dogs, the pressure gradient between the left ventricle and the ascending aorta was measured with high fidelity micromanometers. Left ventricular pressure exceeded aortic pressure in the first 30 to 50% of the ejection period. Aortic pressure exceeded left ventricular pressure during the remainder of the ejection period. The magnitude of these differences varied from 5 to 20 mm Hg. This finding in late systole implies that at this time blood is flowing out of the ventricle under its own momentum and that the aorta is a pressure source for the ventricle. The ascending aorta was suddenly occluded in five dogs to verify this hypothesis. When occlusion occurred in the last third of the ejection period, there was an abrupt fall of left ventricular pressure, apparently confirming the momentum hypothesis.