Extracorporeal membrane oxygenation as a direct bridge to heart transplantation in adults

Venoarterial extracorporeal membrane oxygenation (ECMO) use as a bridge to transplant is extremely infrequent in adults. We investigated patient outcomes of the use of ECMO as bridge to transplant.

United Network of Organ Sharing provided de-identified patient-level data. Between 2003 and 2016, 25,168 adult recipients were identified. Of these, 107 (0.4%) were bridged with ECMO and 6148 (24.4%) were bridged with a continuous-flow left ventricular assist device.

Patients in ECMO group were younger, more likely to have severely disabled functional status, shorter waitlist time, and were more frequently mechanically ventilated than were patients in the continuous-flow left ventricular assist device group. Kaplan-Meier analysis demonstrated estimated posttransplant survival of 73.1% versus 93.1% at 90 days (P < .001) and 67.4% versus 82.4% at 3 years (P < .001) in ECMO and continuous-flow left ventricular assist device groups, respectively. Analysis of a propensity-matched cohort still demonstrated a lower survival in ECMO group at 90 days (74.8% vs 88.8%; P = .025) and 3 years (69.3% vs 82.2%; P = .054). Among the ECMO patients, multivariable logistic and Cox regression analyses showed model for end-stage liver disease excluding international normalized ratio (MELD-XI) score to be the sole contributor to both 90-day (odds ratio, 1.94; 95% confidence interval, 1.00-3.76; P = .050) and 3-year mortality (hazard ratio, 1.47; 95% confidence interval, 1.16-1.88; P = .002). ECMO-supported patients with a high MELD-XI score (>17) were associated with poor posttransplant survival compared with those with a low MELD-XI score (<13) (90 day, 54.4% vs 85.0% [P < .001] and 3 year, 49.5% vs 73.5% [P < .001]).

Bridge to transplant with ECMO was associated with increased early/mid-term mortality, especially in patients with a high MELD-XI score who demonstrated > 50% 3-year mortality. These findings may help to inform future organ allocation policies.