KUALA LUMPUR, Jan 11 – A 57-year-old man with terminal heart disease in the United States has become the first person in the world to get a heart transplant from a genetically modified pig.
David Bennett, who was deemed ineligible for a conventional heart transplant or an artificial heart pump due to his condition (heart failure and an irregular heartbeat), is doing well three days after the experimental seven-hour procedure at the University of Maryland Medicine Centre (UMMC).
Doctors at the UMMC were granted emergency authorisation for the surgery by the US Food and Drug Administration (FDA) on New Year’s Eve to carry out the procedure, on the basis that Bennett would have otherwise died.
“The FDA used our data and data on the experimental pig to authorise the transplant in an end-stage heart disease patient who had no other treatment options,” said Dr Muhammad Mohiuddin, who heads the university’s programme on xenotransplantation – transplanting animal organs into humans.
A day before the surgery was conducted, Bennett said “it was either die or do this transplant,” according to a release issued by the university. “I want to live. I know it’s a shot in the dark, but it’s my last choice,” said Bennett, a Maryland resident and handyman, who had been hospitalised and bedridden for six weeks leading up to the surgery.
On Monday, Bennett was breathing on his own while still connected to a heart-lung machine to help his new heart. The next few weeks are seen as critical as Bennett recovers from the surgery and doctors carefully monitor how his heart is faring.
Dr Bartley Griffith, who performed the surgery, said the breakthrough surgery would bring the world “one step closer to solving the organ shortage crisis”. “There are simply not enough donor human hearts available to meet the long list of potential recipients,” Dr Griffith said.
About 110,000 Americans are currently waiting for an organ transplant, and more than 6,000 patients die each year before getting one, according to the US’s organdonor.gov.
The pig used in the transplant had been genetically modified to remove several genes that would have led to the organ being rejected by Bennett’s body. This was the case in 1984 when a baboon heart was transplanted into a newborn known as “Baby Fae” who survived for only 20 days.
In the heart implanted in Bennett, three genes previously linked with organ rejection were “knocked out” of the donor pig, and six human genes linked with immune acceptance were inserted into the pig genome.
Today, pig heart valves are widely used in humans, and pig skin is grafted on human burn victims. Pigs make the ideal donors due to their size, their rapid growth and large litters, and that they are already raised as a food source.