Ventricular assist devices have been used since the 1990's.
The devices, known as L.V.A.D.'s, for left ventricular assist devices, can help failing hearts pump.
Dr. Gray said he had implanted more than 200 assist devices.
Mechanical hearts, known as ventricular assist devices, are now used as temporary bridges to transplants at Columbia and other hospitals.
The AbioCor, a self-contained total artificial heart, replaces the heart; assist devices leave the heart in place.
The pumps are partial artificial hearts known as ventricular assist devices, and they come in various models.
At Hackensack, his responsibilities included implanting left ventricular assist devices, used to aid patients whose hearts are failing.
Ventricular assist devices aroused notable interests.
The machines are called left ventricular assist devices and help a weak heart pump blood.
Thoratec grossed 60% of its $235 million in revenue from its ventricular assist devices last year.
The use of assist devices, such as crutches or walker, was provided to aid in ambulation.
