Genetically Modified Pig Heart Transplanted Into Human Patient

57-year-old David Bennett was ineligible for a human heart transplant, and this was the last available option to keep him alive.

In a medical first, doctors transplanted a pig heart into a patient in a last-ditch effort to save his life. A Maryland hospital said Monday he's doing well three days after the highly experimental surgery.

While it's too soon to know if the operation really will work, it marks a step in the decades-long quest to one day use animal organs for life-saving transplants. Doctors at the University of Maryland Medical Center say the transplant showed that a heart from a genetically modified animal can function in the human body without immediate rejection.

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