搏动辅助血泵专用的蝴蝶瓣离体性能测试

In Vitro Study of a Newly Designed Bicuspid Valve (Butterfly Valve) for Pulsatile Ventricular Assist Device

目的 对已设计制成的低成本搏动血泵专用瓣膜蝴蝶瓣 (butterfly valve ,B- Y)按 ISO5 840进行国际规范化的离体性能测试。 方法 先对 B- Y瓣进行物理性能测试 ,然后根据 ISO5 840的要求用特殊仪器对 3枚 B- Y瓣作静态及动态性能测试 ,其均值与进行同样测试的 2种美国进口植入型瓣膜 Bjork- Shiley(B- S)瓣和 Medtronic- Hall(M- H)瓣作比较。 结果 B- Y瓣的物理性能符合临床要求 ,在静态测试中 2枚 B- Y瓣膜片过薄 ,在 12 0 mm Hg(1k Pa=7.5 mm Hg)水压下有下凹内翻产生较多静止泄漏量。动态测试方面无搏动流中 B- Y瓣的跨瓣压力落差及搏动流时跨瓣正压压力阶差均较 B- S瓣和 M- H瓣膜略高 ,但其关闭回流量远较 B- S瓣与 M- H瓣为低 ,其舒张泄漏量与B- S瓣相仿 ,而明显低于 M- H瓣。 结论 B- Y瓣的水流阻力较进口瓣膜为高 ,但在临床允许范围以内。其总反流量(关闭回流量、舒张泄漏量 )明显低于进口瓣膜 ,保证了瓣膜的效率和耐用性 ,潜在溶血程度亦因而轻微。 B- Y瓣由于结构简单 ,成本低廉 ,却有与进口植入型瓣膜相仿的功能 ,是其主要特点 。

Objective To evaluate the in vitro performance of a simple bicuspid valve (butterfly valve) for pulsatile ventricular assist device according to the protocol of ISO5840. Methods A comparative study between the butterfly valve(B Y) and 2 reference valves[Bjork Shiley(B S) and Medtronic Hall(M H) valve] were conducted with different test devices. Results In static leakage test, the leakage was prominent in 2 of the B Y valves at a static water pressure of 120 mmHg as a result of faulty fabrication technic of the membrane. The pressure drop and mean transvalvular positive pressure gradiant of B Y valve in steady flow and pulsatile flow test respectively were higher than those of B S and M H valves. Its closing volume, however, was much lower than those of B S and M H valves, and the diastolic leakage, while approximating the B S valve, was again lower than that of the M H valve. Conclusion The bit higher resistance of B Y valve is acceptable for clinical application. The total regurgitation volume (closing volume and diastolic leakage) was substantially lower than that of the 2 imported valves, denoting that B Y valve was more durable and the potential of hemolysis was thus lessened. The cost of B Y valve could be surprisingly reduced owing to its simple structure. It could be effectively used in short term ventricular assist.