DEVELOPMENTAL OF VENTRICLE ASSIST DEVICE (VAD) ACTUATOR

第二阶段计划的目标是设计和开发一种创新的新型驱动器，结合FMT的“磁螺”和“磁弹簧”概念，生产一种高效、长寿命、紧凑的致动系统，优化心室辅助装置（vad）。磁螺钉已经在全人工心脏驱动器中成功演示，作为植入血泵的驱动器具有许多优点；即紧凑，减少磨损和疲劳，以及几乎无损的旋转运动转换为平移驱动。磁簧的添加是特定于VAD应用程序的。由于只有一个泵腔，执行器的返回行程用于将能量存储在磁簧中，从而减小了执行器的物理尺寸和电机功率损耗。magspring概念在第一阶段成功验证，并产生了坚固，高效的VAD。第二阶段的具体目标是：1)构建一个最终的、优化的VAD设计，集成磁螺/磁弹簧执行器和CCF生物血泵；2)开发VAD系统的原型控制器；3)进行VAD系统的体外耐力测试；4)在犊牛身上进行VAD系统的体内试验。拟议的商业应用：作为这项研究成果的结果，一种寿命非常长、可靠的VAD——直径108毫米、厚度58毫米、重量950克——将进入永久植入物市场。根据医学研究所1991年发表的一份报告，这个市场估计每年有3万名候选人。一个足够安全、有效的VAD每年的市场可能高达20万例。

The goal of this Phase II program is to design and develop an innovative, new actuator, combining FMT's concepts of the "magscrew" and "magspring" to produce a highly efficient, long-lived, compact actuating system optimized for ventricle assist devices (VADs). The magscrew, which has already been successfully demonstrated in a total artificial heart actuator, offers many advantages as a driver for implanted blood pumps; namely compactness, reduced wear and fatigue, and nearly lossless conversion of rotational motion to translational actuation. The addition of the magspring is specific to VAD applications. With only one pumping chamber, the return stroke of the actuator is used to store energy in a magspring and, thus, reduce the physical size and motor power losses of the actuator. The magspring concept was successfully validated in Phase I, and results in a rugged, efficient VAD. The Phase II specific aims are to: 1) construct a final, optimized VAD design integrating the magscrew/magspring actuator and a CCF biolized blood pump, 2) develop a prototype controller for the VAD system, 3) perform in vitro endurance tests of the VAD system; and 4) perform in vivo tests of the VAD system in calves. PROPOSED COMMERCIAL APPLICATIONS: As a consequence of this research effort, a very long-lived, reliable VAD - one with a 108-mm diameter, a 58-mm thickness, and a 950-g weight - will be available to the permanent implant market. This market has been estimated to include 30,000 candidates per year, according to a 1991 report published by the Institute of Medicine. A sufficiently safe, effective VAD could have a market as large as 200,000 cases per year.