Yoran C, Yellin E L, Becker R M, Gabbay S, Frater R W, Sonnenblick E H
Am J Cardiol. 1979 Apr;43(4):773-7. doi: 10.1016/0002-9149(79)90077-8.
Acute mitral regurgitation was produced in six open chest dogs by excising a portion of the anterior valve leaflet. Electromagnetic flow probes were placed in the left atrium around the mitral anulus and in the ascending aorta to determine phasic left ventricular filling volume, regurgitant volume and stroke volume. The systolic pressure gradient was calculated from simultaneously measured high fidelity left atrial and left ventricular pressures. The effective mitral regurgitant orifice area was calculated from Gorlin's hydraulic equation. Infusion of nitroprusside resulted in a significant reduction in mitral regurgitation. No significant change occurred in the systolic pressure gradient between the left ventricle and the left atrium because both peak left ventricular pressure and left atrial pressure were reduced. The reduction of mitral regurgitation was largely due to reduction in the size of the mitral regurgitant orifice. Reduction of ventricular volume rather than the traditional concept of reduction of impedance of left ventricular ejection may explain the effects of vasodilators in reducing mitral regurgitation.
通过切除部分二尖瓣前叶，在6只开胸犬身上制造出急性二尖瓣反流。将电磁血流探头置于二尖瓣环周围的左心房以及升主动脉内，以测定左心室的阶段性充盈量、反流量和每搏输出量。收缩压梯度由同时测量的高保真左心房和左心室压力计算得出。有效二尖瓣反流口面积根据戈林水力学方程计算得出。输注硝普钠可使二尖瓣反流显著减少。左心室与左心房之间的收缩压梯度无显著变化，因为左心室峰值压力和左心房压力均降低。二尖瓣反流的减少主要是由于二尖瓣反流口大小减小。心室容积的减少而非传统的左心室射血阻抗降低的概念，可能解释了血管扩张剂减少二尖瓣反流的作用机制。
