An electrically powered total artificial heart. Over 1 year survival in the calf.
An electric motor driven orthotopic artificial heart was implanted in a 110 kg female Holstein calf as part of a series of 12 such implants intended to demonstrate the in vivo durability and compatibility of the device. The device uses pusher plates set into motion by a reversing brushless DC motor and roller screw to alternately eject two cylindrical sac type blood pumps. The pumps use Bjork-Shiley Delrindisc convexo-concave or monostrut valves. The left pump provides an 88-90 ml dynamic stroke volume. Woven Dacron grafts and polyurethane coated Dacron/Lycra cuffs are used to attach the device to the major arteries and atria, respectively. A polyurethane conduit and anchoring skin button bring motor wires percutaneously to an extracorporeal controller. The controller provides balanced cardiac output sensitive to atrial or aortic pressures, without operator intervention. The system is hermetically sealed and uses a simple compliance sac to maintain thoracic pressure between the pumps. The calf recovered uneventfully from surgery and thrived thereafter. She was killed on the 388th post-operative day because of worsening cardiac insufficiency. The previous three operative survivors in this series lived 131, 134, and 204 days. These results indicate the device's good potential for durability and body compatibility.