Evaluating piezoelectric hydraulic pumps as drivers for pulsatile pediatric ventricular assist devices

Abstract

Piezohydraulic pumps are high power density motors, which can be theoretically miniaturized with minimal loss in power output. The feasibility of using piezohydraulic pumps in pulsatile pediatric ventricular assist devices is presented in this study. A theoretical analysis is presented to calculate the piezohydraulic pump dimensions needed to meet flow and pressure requirements. In addition, an existing piezohydraulic pump was incorporated into a ventricular assist device driver to drive a pulsatile pediatric 30-mL stroke ventricular assist device as a proof of concept. The driver was tested at heart rates ranging from 50 to 110 beats per minute in an in vitro mock circulation to characterize its performance. The maximum drive pressure was 33 kPa with a peak flow rate of 6 L/min against a 10-kPa back pressure. The maximum mean flow rate from the ventricular assist device outlet was 3 L/min at 100 beats per minute operation. These results compare well to commercially available systems that output between 25 and 40 kPa drive pressure and flows between 0 and 10 L/min against 10–16 kPa pressures.