Risk stratification of patients listed for heart transplantation while supported with extracorporeal membrane oxygenation

Objectives Extracorporeal membrane oxygenation (ECMO) is used to support patients in severe cardiogenic shock. In the absence of recovery, these patients may need to be listed for heart transplant (HT), which offers the best long-term prognosis. However, posttransplantation mortality is significantly elevated in patients who receive ECMO. The objective of the present study was to describe and risk-stratify different profiles of patients listed for HT supported by ECMO. Methods Patients listed for HT in the United Network for Organ Sharing database were analyzed. The primary outcome was 1-year survival and was assessed in patients bridged to transplant with ECMO (ECMOBTT) and patients who were previously supported on ECMO but had it removed before HT (ECMOREMOVED). Results Among 65,636 adult candidates listed for HT (between 2001 and 2017), 712 were supported on ECMO, 292 of whom (41%) underwent HT (ECMOBTT, n = 202; ECMOREMOVED, n = 90). Most of the patients with ECMOREMOVED were transplanted with a ventricular assist device. In ECMOBTT, recipient age (each 10-year increase), time on the waitlist (both defined as minor risk factors), need for dialysis, and need for mechanical ventilation (both defined as major risk factors) were independent predictors of mortality. ECMOREMOVED and ECMOBTT with no risk factors showed 1-year survival comparable to that in patients who were never supported on ECMO. Compared with patients who were never on ECMO, patients in ECMOBTT group with minor risk factors, 1 major risk factor, and 2 major risk factors had ~2-, ~5-, and >10-fold greater 1-year mortality, respectively (P Conclusions The HT recipients in the ECMOREMOVED and ECMOBTT groups with no risk factors showed similar survival as the HT recipients who were never supported on ECMO. In the ECMOBTT group, posttransplantation mortality increased significantly with increasing risk factors.