US man is successfully transplanted animal heart for first time

A US man has become the first person in the world to get a heart transplant from a genetically-modified pig, BBC News reported.

David Bennett, 57, is doing well three days after the experimental seven-hour procedure in Baltimore, doctors say.

The transplant was considered the last hope of saving Bennett's life, though it is not yet clear what his long-term chances of survival are.

Doctors at the University of Maryland Medical Center were granted a special dispensation by the US medical regulator to carry out the procedure, on the basis that Bennett would otherwise have died.

He had been deemed ineligible for a human transplant, a decision that is often taken by doctors when the patient is in very poor health.

For the medical team who carried out the transplant, it marks the culmination of years of research and could change lives around the world.

Surgeon Bartley Griffith said the surgery would bring the world "one step closer to solving the organ shortage crisis," the University of Maryland School of Medicine said in a release.

The possibility of using animal organs for so-called xenotransplantation to meet the demand has long been considered, and using pig heart valves is already common.

Bennett is hoping his transplant will allow him to continue with his life. He was bedridden for six weeks leading up to the surgery, and attached to a machine which kept him alive after he was diagnosed with terminal heart disease.

On Monday, Bennett was reported to be breathing on his own while being carefully monitored.

But exactly what will happen next is unclear. The pig used in the transplant had been genetically modified to knock out several genes that would have led to the organ being rejected by Bennett's body, the AFP news agency reports.

Griffith said they were proceeding cautiously and carefully monitoring Bennett, while his son David Bennett Jr. told the Associated Press that the family were "in the unknown at this point."

But he added: "He realizes the magnitude of what was done and he really realizes the importance of it."

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