The first person in the world to receive a genetically modified pig heart has died, two months after the surgery.
David Bennett, 57, who had suffered terminal heart disease, received the organ in a last-ditch experimental transplant procedure at the University of Maryland Medical Center on 7 January.
The transplanted heart “performed very well for several weeks without any signs of rejection,” the hospital said, but he died on Tuesday. The cause of death was not confirmed.
In his final weeks, Mr Bennett was able to spend time with his relatives and tuned into the Super Bowl from his hospital bed.
His son David Bennett Jr thanked staff at the hospital for their “exhaustive efforts and energy”, adding: “We were able to spend some precious weeks together while he recovered from the transplant surgery, weeks we would not have had without this miraculous effort.
“We hope this story can be the beginning of hope and not the end. We also hope that what was learned from his surgery will benefit future patients and hopefully one day, end the organ shortage that costs so many lives each year.”
Mr Bennett had been deemed ineligible for a conventional human heart donation due to his complex condition.
He had been bedridden at the hospital since October 2021, reliant on a heart-lung bypass machine to remain alive. He agreed to the pig heart procedure with full knowledge that it was “experimental with unknown risks and benefits”.
Dr Bartley Griffith, who carried out the transplant, said: “We are devastated by the loss of Mr Bennett. He proved to be a brave and noble patient who fought all the way to the end. We extend our sincerest condolences to his family.
“Mr Bennett became known by millions of people around the world for his courage and steadfast will to live.”
Professor of surgery Muhammad Mohiuddin added: “We are grateful to Mr Bennett for his unique and historic role in helping to contribute to a vast array of knowledge to the field of xenotransplantation.
He said the procedure had shown that “the genetically modified pig heart can function well within the human body while the immune system is adequately suppressed. We remain optimistic and plan on continuing our work in future clinical trials.
“As with any first-in-the-world transplant surgery, this one led to valuable insights that will hopefully inform transplant surgeons to improve outcomes and potentially provide lifesaving benefits to future patients.”
The operation had been hailed by UK experts. Professor Sir Nilesh Samani, medical director at the British Heart Foundation, said after it took place: “The idea of using non-human hearts for transplantation for heart failure has been around for more than two decades and this is a remarkable milestone in this journey.
“It was made possible by major advances in genetic engineering to modify the donor pig heart so it is not immediately rejected.”
After the operation, it had emerged that Mr Bennett had previously served a six-year prison sentence after repeatedly stabbing a man during a 1988 bar fight, with his victim left paralysed from the waist down.