Extracorporeal membrane oxygenation liberation before heart transplantation in the modern allocation era: Predictors and one-year outcomes from the National OPTN/UNOS Registry.

Background: The clinical significance of ECMO liberation before heart transplantation remains poorly defined. Objectives: To identify predictors of pre-transplant ECMO liberation and evaluate its association with 1-year post-transplant survival. Methods: We conducted a retrospective cohort study using the national OPTN/UNOS registry, including adult isolated heart transplant recipients supported with ECMO at listing between October 18, 2018 and March 31, 2026. Predictors of pre-transplant ECMO liberation were evaluated using multivariable logistic regression, and the association between ECMO liberation and one-year post-transplant survival was assessed using Kaplan-Meier methods and multivariable Cox regression. Results: Of the 1153 eligible recipients included in the final cohort, 208 (18.0%) were liberated from ECMO before heart transplantation. In multivariable analysis, mechanical ventilation at listing was the only independent predictor of a lower likelihood of ECMO liberation (aOR 0.51, 95% CI 0.34-0.78, p=0.002). Regarding post-transplant outcomes, recipients liberated from ECMO prior to transplantation demonstrated lower unadjusted post-transplant mortality; however, after adjustment for recipient demographic and clinical characteristics, ECMO liberation was not independently associated with 1-year post-transplant survival (aHR 0.81, 95% CI 0.49-1.35, p=0.42). Conclusion: In this contemporary national cohort, ECMO liberation before transplantation occurred in about one in six heart transplant recipients. Mechanical ventilation was associated with reduced likelihood of ECMO liberation, whereas liberation itself was not independently associated with 1-year post-transplant survival after adjustment for recipient demographic and clinical characteristics.