Pediatric Heart Transplantation in France Since the Implementation of the New Allocation System

Purpose Donor-recipient age matching has been introduced into the new French allocation system launched on January 2018. The allocation score is currently weighted by the age difference between the donor and the candidate. The score decreases for candidates 15 to 40 years older than the donor from 100% to 0%. The aim of this study was to evaluate the effect of the new system on pediatric heart transplantation. Methods The study included all new pediatric candidates added to the French waiting list between January 2014 and March 2019 (n=179). The profile and waitlist outcomes of the candidates registered before (2014-2017, n=128) and after (January 2018- March 2019, n=51) the introduction of the new system were compared. The main outcomes were 3-month cumulative incidence (CI) of transplantation, and of waitlist mortality or delisting for worsening medical condition. The CI were estimated using the competing risk analyses and were compared using the Gray's test. Results The medical characteristics of the patients were similar between the 2 periods except for mechanical ventilation which tended to be more frequent in the first cohort (33% vs 18%, p=0.05). The number of new registrations per year increased by 28% in the second period. Donor heart donations decreased in 2018-2019 period but pediatric donor hearts were more often allocated to pediatric candidates (63% vs 48%). The 3-month CI of transplantation was similar between the 2 periods (53% vs 54%, p=0.41). The 3-month waitlist mortality or delisting for worsening medical condition tended to be lower in 2018-2019 (8% vs 17%, p=0.09). Conclusion While access to transplantation remains unchanged, a non-significant decrease in 3-month waitlist mortality has been observed since the implementation of the new system.