Infants Less Likely To Reject Transplanted Hearts

Babies younger than age 1 can receive heart transplants from donors with different blood types without risk of organ rejection, according to a new study.

This finding means that infants who need a heart transplant have a better chance of getting a heart and surviving, say researchers.

The Study

Researchers in Toronto say that a heart from a donor who has Type A blood could be successfully transplanted into a baby who has Type O blood Unlike adults and older children, babies do not yet have the antibodies that would cause rejection of a donor organ from a person who has a different blood type.

"The baby's body educates itself to accept the organ and become tolerant of the blood type," says study co-author Dr. Lori West, a pediatric cardiologist at the Hospital for Sick Children.

She notes that a recipient's tolerance of a donor organ has been one of the major challenges of transplant medicine. It was accepted knowledge that a recipient's body would always reject an organ from a donor who had a different blood type.

"The medical community has been trained that you just don't cross that blood group barrier. For the first time, we have shown that the immune systems of human infants can tolerate intentional induction of a different blood type, West says.

This suggests that more babies will survive congenital heart defects and go on to live fulfilling lives with a donor heart.

"We can use this knowledge to decrease the amount of time a patient must wait for a new heart-we'll be able to use donor organs more efficiently and perform increasingly successful transplants," West says.