Spontaneous Increase in EVAHEART® Pump Flow at a Constant Pump Speed during Exercise Examination

Abstract

Ventricular assist devices have been used for the treatment of severe heart failure. Recently, many types of blood pumps have been developed to reduce major adverse events. EVAHEART® (Sun Medical Technology Research Corporation, Nagano, Japan) is an implantable centrifugal blood pump. In laboratory animal studies, the pump flow of EVAHEART® increases spontaneously during exercise with no changes in pump control parameters. However, this has not been confirmed clinically. The aim of this study was to analyze EVAHEART® performance during exercise. Four male patients were implanted with an EVAHEART®. We evaluated the performance of the EVAHEART® during exercise. Fixed pump speeds were maintained during each test. Measurements during exercise were peak load, peak oxygen consumption (peak VO(2)), pre exercise pump flow, and peak velocity. Pump flow significantly increased from 4.1 ± 0.5 liters per minute (L/min) to 7.2 ± 1.8 L/min during exercise. VO(2) increased from 4.0 ± 0.7 milliliters per kilogram per minute (ml/kg/min) to 14.7 ± 3.3 ml/kg/min. These results indicate that EVAHEART® may support severe heart failure patients not only under static but also under dynamic conditions. Pump flow spontaneously increased during exercise at a constant pump speed.