Development of an electrohydraulic totally implantable artificial heart system

研制了一种电液全人工心脏系统。该系统包括隔膜式椭球形血泵和由再生式无泵直流电机组件组成的电液致动器，以及具有经皮能量传递（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配合。能量转换器，往复液压油交替血泵通过柔性导管，将放置在腹部区域，以尽量减少解剖限制。第二次迭代抽油机，最大输出大于10l /min，输出5L/min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，并通过外部控制器成功启动了10天。在实验过程中，EHTAH以适当的左右平衡稳定地维持了动物的循环…设备产生和散发的热量也是可以接受的。然而，发生了一些机械故障，包括轴承故障导致设备故障。该装置在尸检中表现出良好的解剖适应性，没有损害大血管和邻近组织。因此，EHTAH抽油机被证明具有足够的体内基本性能，尽管需要对检测到的机械问题实施适当的措施。在慢性动物实验中对TET和TOT系统进行了评估。当20瓦的能量最终转移到模拟负载时，由一对环形线圈组成的TET系统在40天内显示出约80%的DC/DC效率。TOT系统在19,200 bps的信号传输速率下允许高达12毫米的偏差。基于这些良好的结果，正在开发第三次迭代系统，以获得更长的耐久性和更高的可靠性。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