From pig hearts to brain dead people

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NYU Langone Health doctors have taken a step closer to making pig organs available for transplantation, successfully implanting pig hearts in two newly deceased people.

Brain-dead patients can be used to safely gather uncollected information about the living and provide physicians with the opportunity to practice before implanting genetically modified pig organs into living people. Deceased patients used in the procedures were declared brain dead and their family members donated their bodies to the research.

“In the recently deceased, the focus is on learning, studying, measuring and trying to really unravel what’s going on in this amazing new technology,” said transplant surgeon Dr. Robert Montgomery. at NYU Langone, in a Tuesday morning. press conference. “We’re able to look very intensively at tissue and blood samples and get a much deeper analysis of what’s going on.”

More than 100,000 people are on organ transplant lists, hoping that someone else’s tragedy will provide them with a kidney, heart, liver or lungs. Pork parts offer a possible alternative. Bioethicists generally support the idea of ​​xenotransplantation, although animal rights activists say they wouldn’t be needed if more people were organ donors.

“It’s amazing to see a pig’s heart beating in the chest of a human being,” said Montgomery, who is a heart transplant recipient himself and hopes to help people who otherwise wouldn’t live long enough to receive a transplant. . “It’s a great privilege for me to witness this in my lifetime.”

The only man who received a pig’s heart, in Maryland earlier this year, lived only two months after the transplant. Although the reason for his death isn’t entirely clear, the NYU Langone team tried to avoid some of the differences between the University of Maryland procedure and traditional human-to-human transplants.

The NYU Langone team didn’t use new immunosuppressive drugs, for example, or put the heart in a special infusion box during transport, which was necessary for the organ to work well in transplants. animal to animal, but may not be necessary. at people’s Place.

The team also extensively checked the porcine version of a virus called cytomegalovirus, which was found in the hearts of humans being treated at the University of Maryland. This pig had been checked for CMV before the transplant, but NYU used two more sensitive tests to make sure the pigs they used were not infected.

Pig hearts are much the same as human hearts, but NYU-Langone transplant surgeon Nader Moazami said he found crucial differences in the first transplant. The heart, from a 160-pound pig, was smaller than he would normally use in a 220-pound man, he said, and the size and length of the blood vessels were different from what he’s seen in nearly 1,000 humans. human transplants he performed.

“It’s not outside our skills, but it allowed us to learn what we need to do and look for to make the operation technically perfect,” Moazami said.

Nader Moazami, transplant surgeon at NYU-Langone, during a transplant procedure performed last week at NYU Langone.  A genetically modified pig's heart was placed in a recently deceased person.

In the second operation, on a 130 pound woman, the heart was a more appropriate size and he knew what to expect in terms of the lengths of the different vessels.

He and his team were able to perform the second transplant 50 minutes faster than the first, in 3 hours and 40 minutes, and he believes he can shave another 20 minutes or so off the procedure. The less time the heart spends outside the body, the less chance there is of damage from a lack of blood supply.

The pig hearts were left with the donors for 72 hours each to check for signs of early immune rejection and to make sure the heart was functioning properly. Moazami said that in both cases heart function was “completely normal, excellent.”

NYU Langone has permission to perform another heart transplant in a recently deceased person. Moazami’s goal is “to make sure we learn as much as possible before we do it in a clinical setting.” Right now, he said, “most of what is known is in non-humans.”

He said he was initially skeptical that the procedures would go smoothly, particularly because he chose to transport the heart on ice, as he would a human heart, rather than using the box. special infusion, necessary to flood the heart with fluids before transplantation. into baboons.

“I want to do what I always do,” he said, but feared before the operation that he might be too stubborn. “When the heart started beating and the blood pressure was good, it was a while.”

Montgomery has already performed two re-deceased pig kidney transplants and may do a third in which the kidney is left in the patient for more than three days.

The NYU Langone team, like a handful of others across the country, is working on clinical trials of pig organ transplants into living people. But the team intends to collect more information first, Montgomery said. “We want to go into phase 1 trials with as much information as possible.”

Researchers have spent decades figuring out how to edit pigs’ genes to avoid immediate rejection when their organs are placed on people.

The pigs used at NYU Langone have 10 modifications to their genes, four so-called knockouts to remove genes that could cause rejection or abnormal growth as well as six knockouts to improve compatibility between the animal and the human.

Lawrence Kelly and Alice Michael, who were partners for 33 years.  Kelly was the first to receive a genetically modified pig heart on June 16, 2022 at NYU Langone Health in New York, NY.

One of the heart recipients, Lawrence “Larry” Kelly, 72, of Hazleton, Pennsylvania, suffered a heart attack while driving alone in rural New York state. His brain was apparently deprived of oxygen for an extended period.

Kelly, who served in the US Navy in Vietnam, was a welder with a history of heart disease and two open-heart surgeries.

“He has had heart problems all his life and if he could have helped a lot of people through this research, he would have been proud to be part of it,” his longtime partner Alice Michael said at the press conference. of Tuesday.

“I didn’t even have to think about the decision (to donate),” she said. “I knew he would want to do it and I had to do it.”

Contact Karen Weintraub at [email protected]

Coverage of patient health and safety at USA TODAY is made possible in part by a grant from the Masimo Foundation for Ethics, Innovation and Competition in Healthcare. The Masimo Foundation does not provide editorial input.

A pig's heart arrives at NYU Langone for a transplant.
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