About 700,000 Americans annually die of heart failure. About half die suddenly, with no chance for therapy. Heart transplantation is the best hope for most of the others, but only about 2,000 organs are available each year, Lederman said. He estimated that about 100,000 Americans annually could prolong their lives with a proven, reliable mechanical heart. There are internal mechanical valves that mimic the action of the natural heart's pump system.
Power comes from a battery pack worn outside the body.
A coil sends power through the skin to an implanted coil that then carries the power to an implanted control package and backup, short-term battery. The external battery pack must be recharged every four hours, but the patient can wear a spare package. The internal battery is kept charged and can operate the heart for about 30 minutes without the external battery. Sensors command the mechanical heart to pump faster when the body is exercising and muscles need more oxygen, Kung said. The pump, implanted in the chest, and its support devices, implanted in the abdominal cavity, weigh a total of 3 pounds.