As in every other arena, advances in technology pave the way for smaller, sleeker, more efficient artificial hearts. Natural as it may seem, xenotransplantation is equally fraught with scientific quandaries, ethical dilemmas and bad publicity.
Xenotransplantation is the use of animal organs in humans.
In 1964, doctors first placed a chimpanzee's heart into a human being. The organ functioned for only two hours before the recipient's immune system rejected it, a complication even in human to human transplants. But recent developments in genetic engineering might present the solution scientists have been looking for since 1905. Primates like chimpanzees and baboons are the animals most closely related to humans. That makes them the best and the worst possible organ donors.