Chandran K B, Lee C S, Shipkowitz T, Chen L D, Yu L S, Wurzel D
Department of Biomedical Engineering, University of Iowa, Iowa City 52242.
Artif Organs. 1991 Oct;15(5):420-6.
An in vitro fluid dynamic study was performed to compare the hemodynamic characteristics of a rigid and a flexible total artificial heart. The artificial ventricles were incorporated into a mock circulatory system, and pressure signals within the ventricular chamber, proximal to the inflow valve and distal to the outflow valve, were obtained. The instantaneous flow rate through the inflow and outflow valves was measured with electromagnetic flow probes. Flow visualization studies performed on the flexible ventricle suggested a vortical motion within the chamber with a smooth washout of fluid in the next pumping phase, but flow disturbances were observed near the wall of the ventricle as well as near the outflow valve. The rate of pressure increase (dP/dt) was smaller in the flexible ventricle as compared with the rigid ventricle for comparable flows and heart rates. The results of the present study indicated that the flexible ventricle with polyurethane valves, having the advantage of ease of implantation and cost savings, can be a viable alternative as a bridge to transplant.
进行了一项体外流体动力学研究，以比较刚性和柔性全人工心脏的血流动力学特征。将人工心室纳入模拟循环系统，并获取心室腔内、流入阀近端和流出阀远端的压力信号。用电磁流量探头测量通过流入阀和流出阀的瞬时流速。对柔性心室进行的流动可视化研究表明，心室内存在涡旋运动，在下一个泵血阶段液体可顺利排出，但在心室壁附近以及流出阀附近观察到了流动干扰。在可比的流量和心率条件下，柔性心室的压力上升速率（dP/dt）比刚性心室小。本研究结果表明，带有聚氨酯瓣膜的柔性心室具有易于植入和节省成本的优点，可作为移植桥梁的可行替代方案。
