Waiting list and post-transplant outcome in Sweden after national centralization of heart transplant surgery

Abstract

BackgroundPrevious studies have demonstrated an association between the annual transplantation rate per center and post-operative mortality after heart transplantation. In 2011, Sweden centralized heart transplants and waiting lists, reducing the number of centers from three to two. This study aimed to assess the active waiting time and pre- and post-transplant mortality rates before and after centralization. MethodsHeart transplantations performed in Sweden between January 1, 2001, and December 31, 2020, were included. Background and donor organ supply data were collected from national registries (Scandiatransplant, STRAX, and SWEDEHEART) and Scandiatransplant, respectively. The Fine and Gray methods were applied to visualize cumulative incidence curves and conduct competing risk regressions. A Cox model was used to adjust for factors influencing time to post-transplant death across eras. ResultsWhen comparing the 10 years before and after centralization, the median active waiting time increased from 54 to 71 days (p=0.015). A decreased risk of mortality on the waiting list was observed in the later era compared to the first (SHR 0.43; [95% CI 0.25-0.74]; p=0.002). The total number of heart transplantation procedures (including pediatric patients) increased by 53% from 377 (mean, 38/year) to 577 (mean, 58/year) in the second era. There was a statistically significant difference in organ utilization between the time eras (p=0.033; Chi2-test). The 30-day and 1-year survival post-transplant rates for adults increased from 90.8% to 97.8% (p<0.001) and from 87.9% to 94.6% (p<0.001), respectively. An adjusted Cox-regression analysis showed a 63% reduction in 1-year mortality between eras (HR 0.37 95%CI 0.22-0.61). ConclusionsThis nationwide retrospective registry study examined patients listed for and undergoing heart transplantation before and after centralization of waiting lists and surgeries in Sweden. Waiting list mortality decreased, and 1-year post-transplantation survival rates improved.