With the approval by the Food and Drug Administration in 2003 of electrically powered ventricular assist systems as destination therapy (i.e., as an alternative to cardiac transplantation), the number of patients with implanted electrically powered devices in the general population is going to steadily increase. While patients are now required to carry a spare primary battery with them at all times, patient compliance will likely become a concern of increasing importance, particularly as more elderly patients receive these implants. The goal for this program is the development of a power adapter that permits ventricular assist device (VAD) and total artificial heart (TAH) systems to safely draw power from the electrical system of most motor vehicles. The power adapter can be used as an emergency backup to normal power sources and/or as a convenience during long car trips. The power adapter is to be factory configurable to meet the power requirements of most, perhaps all, ventricular assist and total artificial heart systems.