David M. Lederman, who led the team of scientists that developed the first fully implantable artificial heart -- which, although it had limited success, prompted further advances in the treatment of late-stage heart disease -- died on Aug. 15 at his home in Marblehead, Mass. He was 68.
The cause was pancreatic cancer, his son, Jonathan, said.
Mr. Lederman, an aerospace engineer, founded a small company called Abiomed in 1981, with the hopes of extending lives while providing a greater degree of independence for gravely debilitated heart patients awaiting a transplant. Working with Robert Kung, the company's chief scientific officer, he brought together a research team (including other aerospace engineers) that designed the AbioCor.
A grapefruit-size device that completely replaces a diseased heart, the AbioCor has no wires or tubes passing through the skin. When it is implanted, a coil transfers power across the skin and recharges the device from the outside. An internal battery and a controller that monitors and regulates the heart rate are implanted in the abdomen.
The AbioCor differs greatly from the first total artificial heart, the Jarvik-7, designed by Robert Jarvik, which required tubes leading from the patient to a small refrigerator-size compressor when it was implanted in Barney Clark at the University of Utah in December 1982. That, too, is the distinction between the AbioCor and another artificial heart implant, the SynCardia, which is also air-driven by a compressor outside the body.
Only 14 of the AbioCor devices were implanted, during clinical trials from 2001 to 2004, with the longest-living recipient surviving 512 days. By comparison, the SynCardia, with its outside-the-body tether, has been implanted in more than 1,000 patients, with the longest-living surviving 1,374 days. One problem with the AbioCor is that it is too large to fit into many patients. Abiomed is currently developing AbioCor II, which is one-third smaller than the original and projected to last up to five years.
Still, the original device has had a significant impact on cardiology. "Despite the fact that the AbioCor was not used in a multitude of patients, it paved the way for further development of completely self-contained artificial heart technology," said Kathy Magliato, a spokeswoman for the American Heart Association and the director of women's cardiac services at the St. John's Health Center in Santa Monica, Calif.
According to the United Network for Organ Sharing, which manages the nation's transplant system, 3,254 patients are waiting for a new heart, and so far this year 1,045 hearts have been donated. It could not be determined how many of those patients waiting for a transplant are supported by devices that evolved from the AbioCor.
Mr. Lederman graduated from Cornell in 1966 with a degree in engineering, physics and mathematics. He went on to earn master's and doctoral degrees in aerospace engineering from Cornell.