Heart Retransplantation Under the 2018 Adult Heart Allocation Policy.

BACKGROUND: The purpose of the present study was to characterize the impact of the 2018 adult heart allocation policy change on waitlist and post-transplant outcomes of heart retransplantation in the United States.

METHODS: All adults listed for heart retransplantation from May 2015 to June 2022 were identified using the United Network for Organ Sharing database. Patients were stratified into eras (era 1 and era 2) based on the heart allocation change on October 18, 2018. Competing risks regressions and Cox proportional-hazards models were used to assess differences across eras in waitlist outcomes and 1-year post-transplant survival, respectively.

RESULTS: Overall, 356 repeat heart transplant recipients were included in analysis, with 207 (58%) retransplanted during era 2. Patients retransplanted in era 2 were more commonly bridged with ECMO (21% vs 8%, P<0.01) and IABP (29% vs 13%, P<0.001) and had a lower likelihood of death/deterioration on the waitlist (subdistribution hazard ratio 0.52, 95% CI 0.33-0.82) compared to those in era 1. Rates of 30-day mortality (7% vs 7%, P=0.99) and 1-year survival (82% vs 87%, P=0.27) were not significantly different among retransplantation recipients across eras. Following adjustment, retransplantation in era 2 was not associated with an increased hazard of mortality (adjusted hazard ratio 1.13, 95% CI 0.55-2.30). The gap in 1-year mortality between primary transplant and retransplant recipients increased from era 1 to 2.

CONCLUSIONS: Heart retransplantation candidates have experienced improved waitlist outcomes following the 2018 adult heart allocation policy without significant changes to post-transplant survival.