Extracorporeal Membrane Oxygenation for Early Graft Dysfunction Following Heart Transplantation: A Systematic Review and Meta-Analysis

Purpose Early graft dysfunction (EGD) is a major cause of morbidity and mortality following heart transplantation (HT). The rate of severe EGD requiring inotropes and/or mechanical circulatory support such as veno-arterial extracorporeal membrane oxygenation (VA ECMO) ranges from 8-20%. Our objective was to systematically review studies that reported on mortality in adult HT recipients who developed severe EGD requiring VA ECMO and conduct a meta-analysis. Methods A systematic search of the literature was conducted until June 1, 2019. Eligible studies included full texts and abstracts published after 2009, ≥10 adults post-HT who developed EGD requiring VA ECMO and reported on mortality. The primary outcome of short-term mortality was defined as death at 30 days and/or hospital discharge and was analysed using a random effects model. A meta-regression analysis to explore heterogeneity based on a priori defined factors was performed. The quality of the evidence was assessed using the GRADE framework. Results Of 17 305 publications screened, 22 observational studies identified 242 deaths in 670 patients from 1987-2018 (Figure). 21 studies (95%) were retrospective and most (86%) were conducted at a single centre. The quality of the evidence was rated as moderate. 14 studies (64%) included patients requiring VA ECMO within 24h post-HT; the rest included an extended early post-HT period (up to 7 days). The median age of patients was 49 yrs (IQR 36-62), 18% (IQR 13-29) were female, 47% (IQR 39-77) had a prior sternotomy, and ischemic time was 198 (IQR 191-224) min. Pooled short-term mortality was 36.8% (95% CI 28.7-43.3, I2 =70%). In the meta-regression, short-term mortality was higher in studies with a higher proportion of females. Conclusion The use of VA ECMO for EGD post-HT is associated with significant clinical benefit with acceptable short-term survival. Future studies are needed to identify factors that may further improve outcomes for patients who experience EGD.