Doctors at the University of Maryland, where the experimental procedure was carried out, came to the conclusion that the man who had the pig heart transplant this year, a ground-breaking one, died from heart failure.
David Bennett, 57, had the experimental procedure in January 2022.
His heart had been replaced during the treatment with one from a gene-edited pig.
Bennett died on March 8th, at the University of Maryland Medical Center, after his condition had deteriorated for many days.
Although doctors have now determined that Bennett died from heart failure, they are still looking into the causes, according to The Baltimore Sun.
Dr. Muhammad M. Mohiuddin, co-leader of the pig heart study, professor of surgery, and director of the cardiac xenotransplantation program at the medical school, said, “We are still trying to figure out what went wrong; we don’t have a single answer.”
In the weeks following the operation, Bennett was able to get out of bed, start his rehabilitation, and spend time with his family, according to the doctors, making the surgery a success.
An autopsy revealed that there were no indications of heart rejection in his body.
Rather, physicians discovered a thickening and subsequent stiffness of the heart muscle, possibly as a response to a medicine intended to prevent infection and rejection, which prevented the heart muscle from relaxing and properly filling with blood.
According to reports, Revivicor, a biotech company, grew the pig whose heart was transplanted into Mr. Bennet and altered the pig’s genome to lower the likelihood of rejection.
An article from the MIT Technology Review from May of this year speculated that Bennett could have died from a pig virus called porcine cytomegalovirus, a preventable condition linked to catastrophic effects on transplants.
The US Food and Drug Administration (FDA) announced that in the future, such transplants will be taken into account on a “case by case basis.”
The FDA spokesperson was quoted by The Baltimore Sun as saying, “Overall, FDA will not allow an investigational product to be used unless it believes that such risks are appropriately minimized and acceptable for the clinical situation.”
“Because of the potentially serious public health risks of possible zoonotic infections, FDA has instituted policies such as long-term patient monitoring and prohibitions against blood donation to mitigate against the risk of infectious disease transmission.”
According to federal government data, there are around 110,000 Americans on the waiting list for an organ transplant, and more than 6,000 people pass away each year while they are on the list.