Outcomes of Simultaneous Heart-Kidney Transplantation Using Donation After Circulatory Death Donors: A Propensity-Matched Analysis from the UNOS Registry.

INTRODUCTION Simultaneous heart-kidney transplantation (SHKT) has become an effective option for patients with end-stage heart and kidney failure; however, the shortage of donors remains a significant challenge. Since 2019, hearts donated after circulatory death (DCD) have been approved and increasingly used, but their safety in the context of SHKT has not been thoroughly studied. METHODS We conducted a retrospective cohort study using the UNOS database from January 2019 to December 2024, identifying 1,761 adults who were primary SHKT recipients. To adjust for baseline differences, we performed propensity score matching (2:1 nearest neighbor), resulting in 298 donation after brain death (DBD) and 149 DCD recipients. The endpoints assessed included 2-year overall survival, delayed graft function (DGF), and kidney graft survival. RESULTS After matching, both heart and kidney out-of-body times remained significantly longer in the DCD group compared to the DBD group (p < 0.001). DGF was more common in the DCD group (36% vs. 26%, p = 0.023). Two-year survival rates were 83.6% in the DCD group and 82.3% in the DBD group (p = 0.88). Robust Cox models showed no association between donor type and two-year mortality (Hazard Ratio: 0.78, 95% Confidence Interval: 0.43-1.44, p = 0.5) or kidney graft failure (HR: 0.61, 95% CI: 0.16-2.26, p = 0.5). CONCLUSION SHKT using DCD donor organs shows similar two-year survival and graft outcomes compared to those using DBD donors, supporting the safe and effective use of DCD organs to expand the donor pool.