目的 为调节左心室辅助设备（left ventricular assist device, LVAD）和自然心脏的能量分配，将LVAD输出能量与心血管系统的总能量之比定义为血流辅助指数，并将其作为控制对象设计血泵控制算法。方法 将血流辅助指数作为控制对象设计基于非参数模型自适应控制算法的血泵控制算法。该算法通过调节实际测量得到的血流辅助指数来跟踪期望血流辅助指数。在心衰、轻微运动和心功能恢复的情况下，利用心血管系统的数学模型验证控制算法的可行性。结果 仿真结果表明：此控制算法能够自动提高泵速来响应外周阻力的减少（5 500 r/min vs. 6 000 r/min）。当将Emax（心肌收缩能力）从80提高到240 Pa/mL来模拟左心室恢复时，血流速自动从5增加到8 L/min。结论 本文提出的控制算法可以通过调节泵的转速来调节LVAD和自然心脏之间的能量分配，有利于促进左心室逆重构。

Objective A blood assist index (BAI), defined as ratio of the output power of LVAD (left ventricular assist device) to the total input power of circulatory system, was proposed in this paper to regulate the energy distribution between LVAD and natural heart. Methods A control strategy based on model free adaptive control (MFAC) algorithm was designed by using BAI as the control variable. The algorithm could track the desired BAI by regulating the pump speed to maintain the measured BAI. A mathematic model of cardiovascular system was used to verify the feasibility of the controller in presence of heart failure, slight physical active and recovery of cardiac function. Results The simulating results demonstrated that the proposed controller could automatically regulate the pump to respond to the reduced peripheral resistance (5 500 r/min vs. 6 000 r/min). When Emax increased from 80 to 240 Pa/mL to simulate the heart recovery, the blood flow rate could increase accordingly from 5 to 8 L/min.Conclusions The proposed control strategy can provide an adjustable and accurate energy distribution between LVAD and native heart by regulating the pump speed, which would be of benefit to promoting left ventricle reverse remodeling.

国家自然科学基金资助项目（11072012，10872013,31070754）