Development of an electrohydraulic totally implantable artificial heart system

研制了电液压全人工心脏(EHTAH)系统。该系统包括隔膜式椭圆形血泵和由蓄热式无泵直流电机组件组成的电液执行器，以及带有经皮能量转移(TET)和光学遥测(TOT)系统的电子系统。基于磁共振成像的计算机图形学证实了抽油机与人体胸腔的良好解剖匹配。能量转换器，往复式液压油，通过灵活的管道替代血泵，将放置在腹部区域，以最大限度地减少解剖限制。在这台第2次迭代的抽油机中，最大输出功率超过10 L/min，在5L/min输出时，能耗约为10W，能效约为12%。该抽油机被植入一只62公斤重的小牛体内，并由外部控制器成功地驱动了10天。在实验中，动物的环路…EHTAH稳定地维持了更多的运动，保持了足够的左右平衡。从该装置产生和散热也是可以接受的。然而，发生了几起机械故障，包括导致设备故障的轴承故障。该装置在尸检中显示出良好的解剖适合性，而不会损害大血管和邻近组织。因此，EHTAH抽油机被证明具有足够的活体基本性能，尽管针对检测到的机械问题需要采取适当的措施。TET和TOT系统在慢性动物研究中进行了评估。由一对环形线圈组成的TET系统在40天内显示了大约80%的DC/DC效率，当20瓦的能量最终被转移到模拟负载中时。TOT系统在19,200bps的信号传输速率下允许高达12 mm的失调。基于这些有利的结果，正在开发第三代系统，以获得更长的耐久性和更高的可靠性。较少

An electrohydraulic total artificial heart (EHTAH) system is has been developed. The system comprises of diaphragm-type ellipsoidal blood pumps and an electrohydraulic actuator consisting of a regenerative pumprushless DC motor assembly, and an electronics system with transcutaneous energy transfer (TET) and optical telemetry (TOT) systems. Excellent anatomic fit of the pumping unit to the human chest cavity was confirmed by computer graphics based on magnetic resonance imaging. The energy converter, reciprocating hydraulic oil to alternate blood pumps through flexible conduits, is to be placed in the abdominal region for minimizing anatomic constraints. In this 2nd iteration pumping unit, the maximum output was over 10 L/min, and the energy consumptin and energy efficiency were around 10 W and 12% at 5L/min output, respectively. The pumping unit was implanted in a 62 kg calf, and was successfully actuated by an external controller for 10days. During the experiment, the animal's circul … More ation was stably maintained by the EHTAH with an adequate left-right balance. Generation and dissipation of heat from the device was also acceptable. There occurred, however, several mechanical failures including bearing breakdown resulting in device malfunction. The device demonstrated good anatomic fit at autopsy without compromising the great vessels and adjacent tissues. Thus, the EHTAH pumping unit was proved to have a sufficient in vivo basic performance, although appropriate measures are to be implemented aginst the mechanical problems detected. The TET and TOT systems were evaluated in chronic animal studies. The TET system consisting of a pair of annular coils demonstrated around 80% of DC/DC efficiency over 40 days when 20 watts of energy was finally transferred into a simulated load. The TOT system at 19,200 bps of signal transmission rate allowed up to 12 mm of misalignment. Based on these favorable results, the 3rd iteration system is being developed to acquire longer durability and higher reliability. Less