Feasibility of using piezohydraulic pumps as motors for pediatric ventricular assist devices

The feasibility of using piezohydraulic pumps in drivers for pediatric ventricular assist devices is presented in this article. In this study a 0.5 kg piezohydraulic pump is incorporated into a ventricular assist device driver to drive a pulsatile pediatric 30 mL stroke ventricular assist device (VAD). The driver consists of a piezoelectric-hydraulic hybrid actuator and volume amplification section. Mechanical tests were performed on the pump and the hybrid actuator and a maximum power output of 5.4 W and 1.6 W were recorded respectively. The driver was tested running at multiple heart rates from 50-80 beats per minute (BPM) in an in-vitro bench top mock circulation to characterize the performance of the driver under a circulatory load. The maximum drive pressure output by the driver was 35 kPa. Peak flow rate from the VAD driven by the new driver was 6 L/min against a 10 kPa back pressure. Mean flow rate from the VAD outlet was 2.35 L/min for 80 BPM operation.