Introduction: Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is a prevailing option for the management of severe early graft dysfunction. This systematic review and individual patient data (IPD) meta-analysis aims to evaluate (1) mortality, (2) rates of major complications, (3) prognostic factors, and (4) the effect of different VA-ECMO strategies on outcomes in adult heart transplant (HT) recipients supported with VA-ECMO. Methods and Results: We conducted a systematic search and included studies of adults (≥18 years) who received VA-ECMO during their index hospitalization after HT and reported on mortality at any timepoint. We pooled data using random effects models. To identify prognostic factors, we analysed IPD using mixed effects logistic regression. We assessed the certainty in the evidence using the GRADE framework. We included 49 observational studies of 1477 patients who received VA-ECMO after HT, of which 15 studies provided IPD for 448 patients. There were no differences in mortality estimates between IPD and non-IPD studies. The short-term (30-day/in-hospital) mortality estimate was 33% (moderate certainty, 95% confidence interval [CI] 28%–39%) and 1-year mortality estimate 50% (moderate certainty, 95% CI 43%–57%). Recipient age (odds ratio 1.02, 95% CI 1.01–1.04) and prior sternotomy (OR 1.57, 95% CI 0.99–2.49) are associated with increased short-term mortality. There is low certainty evidence that early intraoperative cannulation and peripheral cannulation reduce the risk of short-term death. Conclusions: One-third of patients who receive VA-ECMO for early graft dysfunction do not survive 30 days or to hospital discharge, and one-half do not survive to 1 year after HT. Improving outcomes will require ongoing research focused on optimizing VA-ECMO strategies and care in the first year after HT.
