Impact of Pre-Transplant ECMO Duration on Heart Transplant Survival

• Published in: The Journal of heart and lung transplantation Vol. 40; no. 4; p. S85
• Main Authors: McGoldrick, M.T., Barbur, I., Etchill, E.W., Giuliano, K., Hsu, S., Sharma, K., Kilic, A., Choi, C.
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.04.2021
• ISSN: 1053-2498; 1557-3117
• DOI: 10.1016/j.healun.2021.01.1946

The 2018 UNOS heart allocation policy change prioritizes patients bridged to transplant with temporary mechanical circulatory support (tMCS). We investigated how short and medium-term survival varies by duration of pre-transplant ECMO in the pre-allocation change era. We reviewed the OPTN database for adults bridged to transplant with ECMO, excluding multi-organ transplants, retransplantation, and those who initiated tMCS after October 17, 2018. Patients were grouped by quartile of ECMO duration prior to transplantation. Multivariable Cox regression was used to evaluate survival at one and five years. Conditional survival analysis was used to further evaluate those surviving past one year. Logistic regression was used to measure adjusted secondary outcomes such as graft failure or acute rejection. 218 eligible patients who received a transplant between 1994-2018 were evenly distributed into the following groups defined by ECMO duration: Quartile 1 (<8 days), Quartile 2 (8-44 days), Quartile 3 (45-159 days), and Quartile 4 (>160 days). Differences in the baseline characteristics of each quartile group included days on the waiting list (p<0.001), prior malignancy (p=0.01), prior dialysis (p=0.03), and systolic/diastolic blood pressure at transplant (p=0.01, p=0.03). These factors were not associated with survival or secondary outcomes. Survival functions did not differ by ECMO quartile at one year (p=0.44) or at five years (p=0.30). At five years, Quartile 1 was associated with increased mortality (HR=3.22, p=0.048). In a conditional analysis of patients who survived more than one year, Quartile 1 was no longer associated with increased five-year mortality (HR=2.95, p=0.45) and survival functions remained comparable (p=0.45). No duration of ECMO was associated with secondary morbidity outcomes. Among patients who were bridged to heart transplantation using ECMO, neither morbidity outcomes nor survival at one and five years were associated with the duration of ECMO prior to surgery.