Prevalence and Impact of Recurrent Rejection on Pediatric Heart Transplant Recipients: A PHTS Multi-Institutional...

Studies evaluating the prevalence and impact of recurrent rejection (RR) in pediatric heart transplant (HT) are sparse.

The purpose of this study was to describe prevalence and impact of RR on cardiac allograft vasculopathy (CAV) and graft loss after pediatric HT.

Data on HT from January 1, 2000, to June 30, 2020, in the Pediatric Heart Transplant Society database were included. Freedom from RR (≥2 rejection episodes) was compared by era (early: 2000-2009; current: 2010-2020). Outcomes for children experiencing RR were compared with those experiencing 0 or 1 rejection episodes and by type of RR (antibody-mediated rejection [AMR], acute cellular rejection [ACR], mixed [ACR/AMR]).

Of 6,342 HT recipients, 1,035 (17%) experienced RR. In the current era, pediatric HT recipients were less likely to experience RR (P < 0.001). Freedom from CAV was similar for those experiencing RR to those experiencing 0 or 1 episode (96.6% vs 95.3% vs 96.6%); and similar regardless of the type of RR (AMR, ACR, or mixed) (65.5% vs 82.9% vs 100%) (P > 0.05). Freedom from graft loss was significantly lower for those experiencing RR to those experiencing 0 or 1 episode (56.3% vs 72.3% vs 82.3%) and lower for those experiencing recurrent mixed rejection or recurrent AMR compared with those experiencing recurrent ACR (65.3% vs 50% vs 81.8%). Black children experiencing RR subsequently had lower freedom from CAV and graft loss than White children (P < 0.05 for all).

Although prevalence of RR has decreased, children experiencing RR are at greatly increased risk for losing their graft, particularly those who have recurrent mixed or antibody-mediated rejection.