Spontaneous increase in EVAHEART® pump flow at a constant pump speed during exercise examination

Abstract

Purpose: 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 EVA- HEART® 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. Patients and methods: 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 VO2), pre exercise pump flow, and peak velocity. Results: Pump flow significantly increased from 4.1 ± 0.5 liters per minute (L/min) to 7.2 ± 1.8 L/min during exercise. VO2 increased from 4.0 ± 0.7 milliliters per kilogram per minute (ml/kg/min) to 14.7 ± 3.3 ml/kg/min. Conclusion: 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. © 2012 The Editorial Committee of Annals of Thoracic and Cardiovascular Surgery. All rights reserved.