国产气动搏动性心室辅助装置的体外流体力学及动物实验观察

Study of hydrodynamic in vitro and animal experiment of a homebred pneumatic pulsatile ventricular assist device

目的对我国自主研发气动搏动性心室辅助装置进行体外流体力学检验及活体动物应用实验,检验其是否满足临床心室辅助装置要求。方法通过体外模拟循环实验台,30%甘油水溶液作为循环介质,接入心室辅助装置,测定不同模式下血泵的后负荷和流量,以此检测装置的流体力学效果。对6只实验犬应用心室辅助装置左心辅助模式1 h,之后药物KCl诱颤心脏,5 min后除颤。监测心室辅助装置对实验犬的心率、血压支持效果。结果心室辅助装置流体力学实验后负荷100 mm Hg条件下,流量可达到4 L/min以上。实验犬经左室安装辅助装置后,各时间点心率无明显变化。辅助后即刻与辅助前相比收缩压升高约30 mm Hg,舒张压升高约19 mm Hg。辅助过程中未见明显血压波动。诱颤后可维持收缩压60 mm Hg,除颤后撤除装置存活良好。结论该心室辅助装置所产生的流体压力可基本满足临床心室辅助要求,短期应用于实验犬有效、安全、稳定,长期使用效果尚需进一步实验证明。

Objective To study in vitro hydrodynamics of a pneumatic pulsatile ventricular assist device developed ex-clusively by China, and establish an animal model for the detection by the device. Methods The hydromechanics experi-ment was performed on an in vitro test loop using MEDOS-System to drive the ventricular assist device, and lycerl-water so-lution was used as circulating medium. The changes of afterload pressure and the output of the pump were monitored, and theimpermeability and stability were also assessed after the experiment. Six adult dogs were used as the experimental animals.The device worked in the left heart assistance mode for 1 hour then the ventricular fibrillation was induced by potassiumchloride, and then defibrillated after 5 min while the device remained working. The hemodynamics data were monitored con-secutively during the trial. Results The ventricular assist device worked stably and reliably during the hemodynamic exper-iment. The pump can generate more than 4 L/min flow against the afterload pressure of 100 mm Hg. There were no significantchanges in heart rate at different time points in experimental dogs after left ventricular assist. Comparison between after auxil-iary immediately and former auxiliary, the diastolic blood pressure of dogs increased 30 mm Hg with the ventricular assist,and the diastolic pressure increased 19 mm Hg. No obvious fluctuation in blood pressure was found during the auxiliary pro-cess. The diastolic blood pressure stayed at 60 mm Hg when the heart was in ventricular fibrillation, and returned to normalafter electrical defibrillation. Conclusion The ventricular assist device works stably in vitro test, and the pump can meetthe need of adult＇s ventricular assist. It is effective and security to dogs in short term. The effects of long-term use need tobe future proved.