( he said. The other challenges pertain t...)Implantable pumps extend lives of patients too sick for transplant

"Like most new technologies, we're limited by our power supply," Rogers said, "We need to develop a battery that is not only small enough and powerful enough to be safely implanted into the human body, but one that could be recharged through the skin without burning the skin. That way there would be no external parts, which would greatly reduce the incidence of infection."

Another technological challenge involves the pump itself, Rogers said. The Novacor device is a pulsatile pump which contains blood in a polyurethane sack. The blood is then propelled out of the pump between two pusher plates. However, because of its size, it cannot be used in children or comfortably in small women. Rogers said that numerous pump designs are being tested that are smaller and lighter. Durability will also be an issue, he said, since replacing an LVAD entails just as substantial and involved a surgical procedure as the initial placement.

Duke is currently participating in a number of different trials testing different device models and pumps designs.