Chronic left ventricular support with a vented electric assist device.

Based on the success of the pneumatically powered HeartMate (Thermo Cardiosystems Inc, Woburn, MA) left ventricular assist device, researchers at the Texas Heart Institute have begun conducting clinical studies of the vented electric model in bridge-to-transplantation procedures. Like the pneumatic device, the electric device is implanted intraperitoneally, but the blood pump is powered through a percutaneous lead that is connected to two rechargeable batteries. The batteries are worn in a shoulder holster; thus, patients are not tethered to a control console and are fully mobile. Two patients are currently undergoing left ventricular support with the vented electric HeartMate (duration of support, 315 days and 112 days) as they await cardiac transplantation, and they seem to be medically fit for outpatient care and follow-up. This technology may eventually allow selected patients to receive long-term support as a substitute for cardiac transplantation.