Mr. David Bennett, the recipient of the very first pig heart transplant to human beings, passed away on the afternoon of March 8, 2022. This comes two months after the groundbreaking operation was successfully completed.
Dr. Bartley P. Griffith, the heart surgeon who conducted the historic procedure, said that “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 the family.”
Days before Mr. Bennett passed away, his physical condition had already been deteriorating. There was nothing that could be done medically anymore to improve his health. Because of this, the medical team and his family members decided to proceed with compassionate palliative care. In the hours before his passing, he was still able to communicate with his loved ones.
“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,” Dr. Muhammad M. Mohiuddin added. He is the Director of the Cardiac Xenotransplantation Program at the University of Maryland School of Medicine.
What is the Purpose of Xenotransplantation?
Xenotransplantation is the “transplantation, implantation, or infusion” of cells, organs, or tissues obtained from an animal into a human recipient. The field has gained traction because there is an imbalance between the demand for human organs and the supply of them. It serves as an effective medical treatment for individuals who have end-stage organ failure with no other viable interventions.
According to the German Organ Transplantation Foundation, around 8,500 people in the country were on the waiting list for an organ transplant in 2021.
The First Pig Heart Transplant to Human Beings Was Done in January
Last year, Mr. Bennett was admitted to the University of Maryland Medical Center (UMMC). At that time, he had terminal heart disease and was connected to an extracorporeal membrane oxygenation (ECMO) machine.
The ECMO machine is used as a life support device for patients with various life-threatening conditions related to the heart and lungs. At the same time, it is indicated as a temporary intervention while awaiting organ transplant. It allows the two bodily systems of a patient to rest for a while since their supposed functions are performed by the machine instead. Blood flow is redirected to a tube that is connected to the ECMO machine. Then, oxygen is added to and carbon dioxide is removed from the blood that passes through it. After this, the temperature of the blood is regulated to normal body temperature before being pumped back into the patient.
Mr. Bennett needed a heart transplant to continue living. However, he was not medically cleared to undergo a conventional heart transplant at the hospital. Other health institutions also had a similar medical evaluation of him. The other alternative, an artificial heart pump, was also contraindicated for him because of his arrhythmia.
“Either Die or Do”
But not all hope was lost in this situation. Good news came in the form of a genetically-modified heart of a pig. Emergency authorization for the conduct of the surgical procedure was granted by the U.S. Food and Drug Administration on the eve of the new year.
The surgery was the first of its kind. Although experimental and without established risks and benefits, Mr. Bennett consented to the operation after being given all the information needed to make a decision. He said that “It was either die or do this transplant. I want to live. I know it’s a shot in the dark, but it’s my last choice. I look forward to getting out of bed after I recover.” This comes after being in the hospital and confined to bed for months.
At the same time, new drugs were used to ensure that the body would not reject the newly introduced organ.
Dr. Bert W. O’Malley, the President and CEO of UMMC, said that “this is truly a historic, monumental step forward. While we have long been at the forefront of research driving progress toward the promise of xenotransplantation as a viable solution to the organ crisis, many believed this breakthrough would be well into the future. I couldn’t be more proud to say the future is now.”
After the first pig heart transplant to human beings was successfully completed, Mr. Bennett was monitored during the weeks after. The results had been promising since he had shown no signs indicating that his body had rejected the foreign heart. He was able to spend more of his days with his family and even got to watch the Super Bowl. At the same time, he underwent physical therapy for the improvement of his strength.
“Gained Invaluable Insights”
Despite his untimely death, Mr. Bennett still lives on in the unequaled contribution he made in the field of xenotransplantation.
“We have gained invaluable insights learning 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,” said Dr. Mohiuddin. He is the Director of the Cardiac Xenotransplantation Program at the University of Maryland School of Medicine (UMSOM).
Similarly, Dr. Griffith added that “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 work of medical doctors and researchers does not end there. There will be more efforts after the first pig heart transplant to human beings. They will move forward, but this time armed with a deeper knowledge and understanding of xenotransplantation so that more lives can be saved.
German Scientists Follow Suit
With the xenotransplantation research done by the team in the USA, a group of German scientists at Ludwig-Maximilians University (LMU) are breeding pigs that have been genetically modified. This will be done for the purpose of increasing the availability of heart donors for humans.
Eckhard Wolf, one of the research proponents, said that “our concept is to proceed with a simpler model, namely with five genetic modifications” of the Auckland Island breed of pigs. The hearts harvested from the pigs would first be tested on baboons. After this, the team plans to conduct human clinical trials by 2025.