Bridging Adults to Heart Transplant: Temporary versus Durable Mechanical Circulatory Support and Post-Transplant Outcomes

BackgroundThe current United States donor heart allocation system prioritizes patients receiving temporary mechanical circulatory support over those with durable left ventricular assist devices (d-LVADs), but the impact on post-transplant survival remains unclear. ObjectivesTo evaluate post-transplant outcomes in patients bridged with d-LVAD versus t-LVAD before and after the 2018 United Network for Organ Sharing (UNOS) allocation policy change. MethodsUsing the UNOS database, we analyzed 24,795 adult first-time HT recipients from 2011-2023, stratified by device type at transplant: d-LVAD (43.3%), t-LVAD (6.4%), or no LVAD. Outcomes included survival at 30 days, 90 days, 1 year, and 2 years. Risk-adjusted analyses were performed using Cox proportional hazards models. Subgroup analysis examined time on LVAD and the impact of organ preservation on outcomes. ResultsCompared to t-LVAD and no-LVAD recipients, d-LVAD recipients had significantly higher adjusted mortality rates at all time points (hazard ratios ranged from 1.44 at 30 days to 1.18 at 2 years; p < 0.001). The mortality gap was more pronounced under the current allocation era. In patients with device duration data, [&ge;]2 years on LVAD was associated with a 39% higher 1-year mortality risk (HR 1.39, 95% CI 1.15-1.68). No significant differences in 1-year mortality were observed between DCD donor and machine-perfused donor transplant subgroups by LVAD status. ConclusionsPost-transplant survival is worse with d-LVAD bridging, particularly under current allocation rules, and prolonged LVAD support further elevates risk. These findings underscore the need to reevaluate LVAD strategy and transplant prioritization, considering evolving allocation policies. Condensed AbstractIn a UNOS analysis of 24,795 heart transplants (2011-2023), patients bridged with durable LVADs (43.3%) consistently experienced worse post-transplant survival than those with temporary LVADs (6.4%) or no device. Adjusted mortality was higher at all time points (HR 1.44 at 30 days to 1.18 at 2 years; p<0.001), with disparities becoming more pronounced after the 2018 allocation change. Prolonged LVAD use ([&ge;]2 years) further increased the risk. These findings highlight the need to reevaluate durable LVAD strategies and transplant prioritization. Preprint ServerNone