Duration of Bridge-to-Transplant Extracorporeal Membrane Oxygenation and Heart Transplant Survival

Background. The 2018 Organ Procurement and Transplantation Network (OPTN) heart allocation policy change prioritizes patients bridged to transplant with mechanical circulatory support (MCS) devices, including extracorporeal membrane oxygenation (ECMO). As a result, the use of ECMO has significantly increased. Methods. We reviewed the OPTN database for adult patients undergoing heart transplant after bridge with ECMO between January 1st 2000 and October 18th 2018. We excluded patients with ≥180 days of ECMO duration, prior transplants, and those using additional MCS devices. Survival and morbidity outcomes of patients with ≥7 days of pre-transplant ECMO were compared to those of patients with <7 days. Results. Of 362 eligible transplant recipients, 163 (45%) utilized <7 days of pre-transplant ECMO and 199 (55%) utilized ≥7 days. Those with ≥7 days were younger (median age: 43 [28-54] vs. 50 [36-57] years, p=0.006) and more likely to have temporary waitlist inactivity (18% vs. 7%, p=0.003) with significantly longer duration of ECMO use (median: 14 [9-24] vs. 4 [2-5] days, p < 0.001). Patients with ≥7 days of ECMO had comparable survival to those with <7 days at one year (81.1% vs. 79.4%, p=0.64) and five years (61.1% vs. 49.3%, p=0.27). After adjustment for clinically relevant variables, duration of ECMO ≥7 days did not increase mortality at five years (HR = 0.90, p=0.59). Conclusions. Longer duration of ECMO (≥7 days vs. <7 days) among patients successfully bridged to transplant is not associated with increased mortality or selected adverse outcome, including graft failure or rejection, at up to five years.