Doctors at Duke University Hospital have performed the country's first-ever adult heart transplant through a process called donation after circulatory death (DCD), and one of the surgeons involved says the process could expand the heart transplant donor pool by as much as 30%.
How the process works
Typically, heart transplants "depen[d] on a declaration of brain death," according to a Duke release. By contrast, DCD transplants occur after circulatory death and rely on hearts that have stopped beating, when the patient is not technically brain dead but has been declared dead. Jacob Schroder, one of the doctors who led the procedure, said, "Although [donors] are not technically brain-dead, their chance of recovery is zero."
DCD is routinely used in the United States for transplants of organs besides the heart, and DCD heart transplants have been done in Europe and Australia, according to the Duke release.
For the DCD transplant at Duke, doctors reanimated the heart using the TransMedics Organ Care System, a warm perfusion pump approved by FDA for clinical trials at five medical centers, including Duke, in the United States, according to CNN.
After the donor's heart stopped, doctors waited five minutes for the patient to be pronounced dead, CNN reports. They then perfused the heart with a cold solution and gathered other organs that were to be donated.
Then, the doctors placed the heart into the TransMedics Organ Care System where it was transfused with warm blood and resumed beating. The heart stayed on the system until the recipient was ready for transplant, and once the recipient was, "the heart was put back to 'sleep' and implanted through a standard heart transplant," CNN reports.
According to Duke, the recipient of the heart transplant is doing well.
According to Schroder, the ability to perform DCD heart transplants in the United States could expand the heart transplant donor pool by up to 30%.
"Currently, a conservative estimate would be that there are 250,000 people with end-stage heart failure who could theoretically qualify for a heart transplant," Schroder said. "Due to the extreme lack of suitable donors, we only do 2,500-3,500 transplants per year using donation after brain death donors."
Schroder said that there is currently "a huge disparity between the number of people who need a transplant and those who get one." He explained, "The reason for that is a lack of suitable donors, and so doing things like … donation after circulatory death is going to have a major impact."
Pedro Catarino, director of transplantation at Royal Papworth Hospital in the United Kingdom, which has performed 74 successful DCD transplants, said that often DCD hearts could be better than hearts following brain death because of the donor.
"Consider the alternatives of a 50-year-old standard lady donor who died of a brain hemorrhage (often related to high blood pressure, which can also affect the heart). All her measures of heart function are good, and she is to all intents and purposes a 'standard' and good donor—picked up quickly by any center in the USA," he said. "In comparison, you may have a 20-year-old man who had a severe unrecoverable brain injury after an overdose but is not brain dead. Even after 30 minutes of injury, the younger, larger (male vs. female) heart is likely to produce more 'power' than the former."
Meanwhile, Ashish Shah, chair of cardiac surgery at Vanderbilt University Medical Center, who was not involved in the Duke procedure, noted the operation isn't without its risks. "The major concern is that there is a period of time when the heart has no blood or oxygen getting to it prior to infusing it with the preservation solution and ice," he said. "This period can vary considerably and may injure the heart permanently. That injury may not be seen until later, but it's the one worry about using these organs."
Shah said he believes the impact of DCD heart transplants will be limited. "Certainly it will increase the number of donors, but there are still logistical things that will make this more difficult for smaller centers, and there will be a need for more expertise among the recovery teams," he said. "We have used these type of donors for lung transplants for several years in the US and haven't seen a dramatic increase in such donors" (Kim, CNN, 12/3; Bote, USA Today, 12/4; Eanes, Raleigh News & Observer, 12/4; Duke release, 12/4).