犬左心房至主动脉旁路机械性左心室辅助的评估。

Evaluation of mechanical left ventricular assistance with left atrium to aorta bypass in dogs.

作者信息

Sato N, Kagawa Y, Nitta S, Mohri H, Horiuchi T

出版信息

Tohoku J Exp Med. 1981 Aug;134(4):375-84. doi: 10.1620/tjem.134.375.

DOI:10.1620/tjem.134.375

Abstract

Effects of the left heart bypass (LHB) by the left atrium (LA) to the aorta (AO) shunt on the heart were evaluated by measuring such parameters as tension time index (TTI), diastolic pressure time index (DPTI), DPTI/TTI ratio, coronary blood flow and myocardial oxygen consumption (MVO2) in open-chest dogs. A pneumatically driven bypass pump made of polyurethane was utilized in this study. No significant change of MVO2 was observed with surgical maneuver to connect the LA-AO LHB pump to experimental animals. During synchronous pumping of LHB, TTI decreased by 35%, MVO2 decreased by 56% of the control and DPTI/TTI ratio increased by 79%. However, coronary flow decreased by 35%, presumably due to autoregulation mechanism of the coronary circulatory system. Both synchronous and asynchronous LHB demonstrated the same level of effect in volume unloading. However, significant diastolic augmentation was noted only in the former. LA-AO LHB, which has a sufficient supporting effect and does not damage the ventricular wall, was considered to be very useful for temporary support for the failing heart, especially for postoperative low output state.

摘要

通过测量开胸犬的张力时间指数（TTI）、舒张压时间指数（DPTI）、DPTI/TTI 比值、冠状动脉血流量和心肌耗氧量（MVO2）等参数，评估经左心房（LA）至主动脉（AO）分流的左心旁路（LHB）对心脏的影响。本研究使用了由聚氨酯制成的气动驱动旁路泵。将 LA-AO LHB 泵连接至实验动物的手术操作未观察到 MVO2 有显著变化。在 LHB 同步泵血期间，TTI 降低了 35%，MVO2 降至对照组的 56%，DPTI/TTI 比值增加了 79%。然而，冠状动脉血流量减少了 35%，推测是由于冠状动脉循环系统的自身调节机制所致。同步和非同步 LHB 在容量卸载方面显示出相同程度的效果。然而，仅在前者中观察到显著的舒张期增强。LA-AO LHB 具有足够的支持作用且不损伤心室壁，被认为对衰竭心脏的临时支持非常有用，尤其是对于术后低心排血量状态。