Biopsy-diagnosed antibody-mediated rejection based on the proposed International Society for Heart and Lung Transplantation working formulation is associated with adverse cardiovascular outcomes after pediatric heart transplant

Biopsy findings of AMR (pAMR 2 or higher) are common after pediatric HT. Like cellular rejection, biopsy grading of AMR seems important to delineate those at risk of adverse events. Our results suggest that pAMR 3 is associated with worse CV outcomes. Widespread surveillance for pAMR with a uniform grading system is an important next step to further validate these findings in the pediatric HT population.