Picture: A sitting baby 
The safety of blood-incompatible
heart transplants depends on
the age; © Hemera

The analysis, based on national data reported to the United Network for Organ Sharing (UNOS), found that transplanting infant hearts across incompatible blood group is as safe as transplantation with compatible blood group types.

“There was no difference in outcome between incompatible and compatible transplantation in these infants,” said Luca A. Vricella, M.D., senior author of the study and chief of pediatric heart transplantation at Johns Hopkins Medical Institutions in Baltimore, Md. “Survival between the two groups was similar at three years.”

Vricella said the impact of using incompatible donor hearts could significantly reduce the number of infants who die while on the waiting list to receive donor hearts. “Mortality could be reduced by at least 20 percent by using incompatible donors,” she said. Up to 40 percent of infants die while waiting for a donor heart. The average wait on the list exceeds two months.

The study examined data on infant heart transplant recipients reported to UNOS from 1999 to 2007. Of the 591 infants who underwent transplantation, 35 infants (6 percent) received hearts from ABO-incompatible donors. Two ABO-compatible infants died from hyperacute rejection, while no ABO- incompatible infants died from hyperacute rejection. ABO-incompatibility did not predict mortality. The statistical analysis was adjusted for the different size cohorts, assuring statistical significance.

Survival in both groups reached 75 percent at three years after transplantation. Infants with congenital heart disease (defects existing since birth) represent the predominant group requiring transplantation. Until age 12 to 14 months, infants have immature immune systems with little or no production of these antibodies. That means they will not have pre-formed antibodies against the donor heart, lowering the risk of rejection.

MEDICA.de; Source: American Heart Association