Status of implantable energy systems to actuate and control ventricular assist devices.

A major goal of the Devices and Technology Branch of the National Heart, Lung, and Blood Institute (NHLBI) is the development of a family of devices that can be effectively used in the rehabilitation of patients with advanced heart disease. The development of implantable circulatory assist and total heart replacement devices forms a major portion of this goal. A miniature, implantable energy converter is a key to the development of a tether-free, implantable ventricular assist system. This paper defines the energy system design requirements, identifies key subsystems, briefly reviews NHLBI-sponsored research activities, defines the current research status, and identifies current problem areas and research issues.