完全磁悬浮心室辅助装置的体外模拟循环系统实验研究

目的研究我国自主研发的第3代完全磁悬浮心室辅助装置(CH-VAD)对于心衰患者的循环辅助效果。方法建立一套体外模拟循环系统(mock circulatory system,MCS)。该系统能够模拟人体健康休息状态以及心力衰竭状态,并与CH-VAD协同工作,测试CH-VAD在连续流状态下的辅助效果。另外,对CH-VAD的搏动流控制方法进行测试,该模式采用正弦波速度波形,使CH-VAD的运行与MCS心室周期同步。结果 CH-VAD在正常连续流状态下能够使心衰状态的血流动力学参数(动脉压、心排量)恢复到正常范围。初步的搏动流测试结果显示,当前的速度搏动幅值对血流动力学影响较小,搏动流状态下与连续流状态所对应的平均动脉压、动脉脉压、平均心排量与心排量波形等差异不大。结论 CH-VAD能够通过搏动控制器产生一定程度的速度搏动,提供足够的心室辅助,并可以进一步改良优化,提供符合生理条件的搏动血流。所研制的MCS能够提供心室辅助装置以及其他机械循环辅助装置一个有效、可控的体外测试平台,是机械循环辅助装置设计、优化和验证的重要工具。

In vitro simulation experimental study of a fully magnetically levitated ventricular assist device based on mock circulatory system

Objective To investigate the circulatory supporting effect of the third generation fully magnetically levitated China Heart ventricular assist device (CH-VAD) under heart failure (HF) condition. Methods An in vitro mock circulatory system (MCS) was developed. This system could simulate a healthy adult under resting state and a patient with heart failure, and incorporate the CH-VAD to evaluate the assisting performance under continuous flow mode. Furthermore, CH-VAD was equipped with a pulsatile flow controller and its initial performance was accessed. The pulsatile mode was obtained by using sinusoidal velocity waveform of the pump which synchronized the CH-VAD with the ventricle simulator of the MCS. Results CH-VAD under continuous flow mode could recover the hemodynamic parameters (arterial pressure and cardiac output) under HF condition to normal range. Preliminary pulsatile test results showed that amplitude of current pulse speed had a minor influence on the hemodynamic performance. CH-VAD under continuous flow and pulsatile flow mode could obtain comparable mean arterial pressure, systolic arterial pressure, diastolic arterial pressure and mean flow. Conclusions CH-VAD can generate a certain degree of speed pulse via appropriate pulsatility control, so as to provide sufficient support on ventricular function. Further optimization on pulsatile controller of CH-VAD is required to conform to natural physiology. The developed MCS can be utilized as an effective and controllable in vitro platform for design, optimization and verification of VADs or other mechanical circulatory support devices.