A pediatric heart transplant procedure pioneered by Canadian doctors—once deemed impossible—has been shown to be at least as effective as the traditional approach, according to in The Lancet Child & Adolescent Health.
was developed in the mid-1990s, after a Canadian transplant team led by realized that infants under the age of two have immature immune systems that would allow them to accept life-saving replacements for their defective hearts from donors with incompatible blood types.
“It’s really important to see it has not only helped these very sick babies to get transplants faster, but also to live as long, with no more rejections, and better outcomes with regards to infections, as children who received a matched blood group heart,” said principal investigator Simon Urschel, associate professor of pediatrics in the 黑料不打烊’s Faculty of Medicine & Dentistry, director of pediatric cardiac transplantation at the and member of the
ABO-incompatible heart transplantation is now routinely carried out in Canada and some other countries, but not everywhere. That should change thanks to these new study results, Urschel said.
“For example, (the agency responsible for transplants in eight European countries) still considers it an inferior option to be used with caution,” he said. “That concern will probably be relieved in those last places that were reluctant to do it, now that we have shown it is safe.”
About 50 per cent of the population is born with type O blood, while 35 per cent has A type and 15 per cent has B or AB type blood. Organs from a donor with type O blood can be accepted by anyone, but adult type O patients can receive only type O organs. The development of ABO-incompatible pediatric heart transplantation meant that twice as many organs would be available to type O infants born with heart defects.
Faster surgery, fewer complications
Urschel and his team analyzed data from more than 2,200 infant transplant recipients in Canada, the United Kingdom and the United States from 1999 to 2018. The records were from the registry, an international research collaboration that collects data from 58 transplant centres. This resulted in more than 11,000 cumulative patient-years of observation, by far the largest study of its kind.
Three hundred sixty-four of the babies received ABO-incompatible transplants, while 1,842 received ABO-compatible hearts. “We wanted to compare apples with apples, so the children were matched by characteristics such as their underlying disease and the age at which they underwent surgery,” Urschel said.
The researchers found the survival rate was the same between the two groups, as were the rates of acute and chronic organ rejection and the risk of developing leukemia after transplant. They also examined the rates of post-transplant bacterial, viral and fungal infections, which they were concerned might be higher among the ABO-incompatible transplant recipients.
“Interestingly, we found that there were fewer of the infections that we were worried about in the ABO-incompatible patients,” Urschel said.
Earlier showed that wait times for these patients were significantly shortened, with the average time to transplant being about 50 per cent shorter thanks to the innovative transplant technique.
“It’s easier and faster to find a heart for these patients, which is crucial because they are extremely sick, often on mechanical heart support devices or on ventilators in