ABO-incompatible heart transplantation in infants: analysis of the united network for organ sharing database

ABO-incompatible heart transplantation, traditionally contraindicated because of the risk of hyperacute rejection, has been used selectively in recent years. Infants have limited production of isohemagglutinins, which may lower the risk of hyperacute rejection. A large national database was used to analyze the effect of ABO incompatibility on outcomes after heart transplantation in infants.

Heart transplant recipients aged younger than 1 year reported to the United Network for Organ Sharing from 1999 to 2007 were divided according to donor-recipient ABO incompatibility or compatibility. Outcomes included Kaplan-Meier survival and hyperacute rejection. Propensity-adjusted Cox regression modeling was used to identify predictors of mortality.

Of 591 infants that underwent heart transplantation, 35 (6%) received allografts from ABO-incompatible donors. ABO-incompatible recipients trended toward more congenital heart disease (71% vs 66%; p = 0.06) and were less likely to have dilated cardiomyopathy (11% vs 29%; p = 0.02). One ABO-incompatible infant had hyperacute rejection requiring retransplantation. No ABO-incompatible infant and 2 ABO-compatible infants died from hyperacute rejection. Survival was similar at 3 years. Propensity-adjusted Cox regression analysis demonstrated that ABO-incompatibility did not predict mortality (hazard ratio, 3.61; 95% confidence interval, 0.26-49.0; p = 0.33).

ABO-incompatible heart transplantation can be performed safely in infants without greater incidence of hyperacute rejection. ABO-incompatible heart transplantation should be strongly considered in infants to maximize donor organ utilization and reduce waiting-list mortality.