Abstract 11117: Risks Associated with Allosensitization in Pediatric Heart Transplantation
Allosensitization among children considered for heart transplantation remains a great challenge. Controversy exists as to best approach for those with elevated panel reactive antibody (PRA) with some centers suggesting that such patients can undergo transplantation with satisfactory survival without the need for prospective crossmatching. To date, analysis of allosensitization in children has been limited to single center reports. We sought to define the association between elevated PRA and outcomes using data from the multi-institutional Pediatric Heart Transplant Study Group. Methods: Between 1/93 and 12/08 3016 pts (> 1mo of age) were listed for heart tx, PRA data were available for 2500 (83%) and 2237 underwent transplantation with pre-tx PRA data available for 1904 (85%). At listing 10.2% of pts had PRA >20%. Factors associated with high PRA were older age at listing, status 1 at listing, prior VAD, and prior Norwood procedure. An elevated PRA at listing was associated with longer time to tx (p <.001) and higher risk of death while waiting (p <.001). Of subjects with PRA >50%, only 48% had been transplanted by 1 yr on the waitlist, as compared to 74% of those with PRA <10%. Waitlist mortality for 12 mo reached 25% in those with PRA >50%. Survival to 1 yr following transplantation was significantly lower in those with PRA >50% vs PRA<10%, 73% vs. 91%, respectively, p<.001. Elevated PRA was also associated with a significantly higher risk of rejection (p=.04), but not associated with coronary allograft vasculopathy. Those subjects with elevated PRA who had a negative prospective crossmatch had no significant difference in survival when compared to those without allosensitization. Conclusions: Significant allosensitization is associated with 3x increased risk of death within the first transplant year. While prospective crossmatching may lead to longer waiting time and higher pre-transplant attrition, it does reduce the risk of allosensitization on post-transplant mortality. Hence, the decision to transplant the allosensitized child without prospective crossmatching should be made in light of these competing risks.
- © 2010 by American Heart Association, Inc.