Increasing Donor-Recipient Weight Mismatch in Infant Heart Transplantation: Waitlist Benefits and Equal Outcomes

Infants awaiting pediatric heart transplantation (PHT) have long waitlist duration and high mortality due to donor shortage. This study examined whether increased donor-recipient weight ratio (DRWR) higher than 2.0, the recommended cutoff, resulted in adverse outcomes. 1,392 infants undergoing PHT between 2007 and 2020 were included. They were divided into three groups: A (DRWR ≤ 1.0, n = 239); B (DRWR 1.0–2.0, n = 947; C (DRWR > 2, n = 206). DRWR ranged from 0.5 to 4.1 and other variables were comparable between groups. Patients in group C were more likely to be ventilated, receive an ABO blood group-incompatible heart, and have longer donor ischemia times. The DRWR group was not associated with operative death in either congenital or cardiomyopathy patients. Infants in group C had shorter waitlist durations and no demonstrable increase in adverse outcomes.