On Friday, January 7, 2022, surgeons at the University of Maryland Medical center successfully transplanted the heart of a genetically modified pig into a human. The life-saving operation is the first instance of a human receiving an animal heart, and if successful in the long term, heart transplants like these could save thousands of lives in the future.
On Monday, January 11, doctors reported that Dave Bennett, the 57-year-old patient who received the heart transplant, is currently recovering after the experimental surgery. He is breathing without a ventilator but is still on an ECMO machine which helps his new heart pump blood. The next few weeks will be critical in the patient’s recovery, and the outcome of the surgery is still uncertain.
Bennet had been deemed ineligible for a human heart transplant. Unfortunately, there are many people like him in the US that don’t make it on organ transplant waitlists, as well as around another 100,000 who are currently waiting for organ transplants. Sadly, thousands of people pass away every year due to the deficit of human organ donors, and the scientists who work in the field of animal-to-human transplantation, or xenotransplantation, hope to change that.
Bennett agreed to the life-saving surgery, hoping it would allow him to return to his Maryland home and see his family and dog once again - reports USA today. “This is nothing short of a miracle,” Dave Bennet’s son David stated on Sunday. “That’s what my dad needed, and that’s what I feel like he got.” The patient is a 57-year-old handyman whose only chance at recovery was the experimental transplant. "Regardless of what happens, I want to help other people," Bennett was quoted as saying to his son prior to the surgery.
The heart transplant surgery lasted 9 hours. The donor, a 1-year-old, 240-pound (109 kg) pig, was bred specifically for heart transplants, and its DNA was genetically manipulated in 10 places before birth. Since pig and human organs are quite similar and scientists have already seen a lot of success in transplanting pig heart valves into humans, these animals are the best choice. The researchers who raised the donor state that some of the pig’s heart genes were turned off and new human genes were added to reduce the risk of rejection by the recipient’s immune system. The size of the animal was also genetically edited, as a standard male pig’s heart would be too large for a human.
Dr. Muhammad Mohiuddin, co-author of The University of Maryland Medicine research team that has been working on xenotransplantation for years and previously tested these kinds of pig heart transplants in baboons, stated that they managed to keep the animals alive for up to 9 months.
The FDA granted emergency authorization for the experimental surgery, and it was conducted on January 7, 2022. According to a statement to The New York Times of Dr. Bartley Griffith, the surgeon who performed the transplant, the surgery went well. “We are thrilled, but we don’t know what tomorrow will bring us. This has never been done before.”
You can view a detailed video of the transplant published by the University of Maryland School of Medicine here - First-Ever Pig to Human Heart Transplant (Official Video).
Fair warning - it's not for the easily impressionable and faint-hearted.