Impella 5.5 versus intra-aortic balloon pump for bridging dual organ heart-kidney transplants: Analysis of the UNOS database

Background: There has been an exponential increase in the utilization of temporary mechanical support devices for bridging Status 2 heart transplant candidates. The aim of our study is to determine outcomes in dual organ heart/kidney recipients for patients bridged with an Impella 5.5 versus IABP. Methods: We evaluated the UNOS database and analyzed Status 2 patients who underwent dual organ heart/kidney transplantation after being bridged with an Impella 5.5 or IABP from October 2019 (time of Impella 5.5 FDA approval) until March 2024. Results: A total of 457 patients who underwent Heart/Kidney transplant (HKT) were identified, of which 73% (334/457) were bridged with an IABP and 27% (123/457) with an Impella 5.5. Within the IABP cohort, 37% (122/334) were on dialysis pre-transplant compared to 43% (53/123) in the Impella group ( p = 0.409). Patients in the Impella group had worse functional status, liver function, and filling pressures. There was no difference in the need for dialysis post-transplant (32% vs 29%, p = 0.613). Survival at 30, 180, and 360 days and the rates of primary graft dysfunction, acute, and chronic rejection were similar between the two groups. Conclusion: Both IABP and Impella appear to be safe for bridging dual organ heart and kidney transplant candidates, with comparable post-transplant heart and kidney graft function, complications, and survival up to 2 years. Patients receiving Impella 5.5 appear to be sicker and as a result, this percutaneous temporary mechanical circulatory support device may confer some advantages, especially for patients with dual organ failure who undergo transplantation.