The New French Heart Allocation System Has Improved Access to Transplantation in Adolescents

Abstract

<h3>Purpose</h3> The French allocation system launched on January 2018 introduced donor-recipient age matching. The allocation score decreases linearly from 100% to 0% for candidates 15 to 40 years older than the donor. The aim of this study was to evaluate the effect of the new system on waitlist outcomes in pediatric heart candidates. <h3>Methods</h3> All candidates registered on the national waiting list before 18 years old between January 2010 and December 2020 were included in this cohort study using the national registry Cristal. Waitlist outcomes of the candidates registered before (2010-2017, n=266) and after (2018-2020, n=99) implementation of the new system were compared. The main outcomes were cumulative incidences of transplantation and waitlist mortality or delisting for worsening medical condition. Cumulative incidences were estimated using competing risk analyses with transplantation and death or delisting for worsening medical condition as the competing events. <h3>Results</h3> During the study period 365 listings in 358 candidates resulted in 274 heart transplantations. Among the 365 transplant candidates (195 males, 11+ years n=175, cardiomyopathy n=221, congenital heart disease n=72, retransplantation n=13, other n=59) 179 were CMV-negative, 147 had HLA alloantibodies, 191 were on inotropic infusion, 67 on short-term mechanical circulatory support (MCS) and 41 on long-term MCS at listing. Overall, the 12-month cumulative incidence of transplantation and waitlist mortality was 77% [72-81] and 18% [14-22], respectively. In adolescents the cumulative incidence of transplantation increased after implementation of the new system while waitlist mortality did not change (Figures). In children 0-10 years of age no difference was observed between the 2 periods. <h3>Conclusion</h3> Since the implementation of the new allocation system, access to transplantation has improved in adolescents. Improvement in access to transplantation in younger children requires an expansion of the small children heart donor pool.