OBJECTIVES: The clinical profile and outcomes of patients with Coronavirus Disease 2019 (COVID-19) who require veno-arterial extracorporeal membrane oxygenation (VA-ECMO) or veno-arterial-venous extracorporeal membrane oxygenation (VAV-ECMO) are poorly understood. We aimed to describe the characteristics and outcomes of these patients and to identify predictors of both favourable and unfavourable outcomes. METHODS: ECMOSARS is a multicentre, prospective, nationwide French registry enrolling patients who require veno-venous extracorporeal membrane oxygenation (ECMO)/VA-ECMO in the context of COVID-19 infection (652 patients at 41 centres). We focused on 47 patients supported with VA- or VAV-ECMO for refractory cardiogenic shock. RESULTS: The median age was 49. Fourteen percent of patients had a prior diagnosis of heart failure. The most common aetiologies of cardiogenic shock were acute pulmonary embolism (30%), myocarditis (28%) and acute coronary syndrome (4%). Extracorporeal cardiopulmonary resuscitation (E-CPR) occurred in 38%. In-hospital survival was 28% in the whole cohort, and 43% when E-CPR patients were excluded. ECMO cannulation was associated with significant improvements in pH and FiO2 on day 1, but non-survivors showed significantly more severe acidosis and higher FiO2 than survivors at this point (P = 0.030 and P = 0.006). Other factors associated with death were greater age (P = 0.02), higher body mass index (P = 0.03), E-CPR (P = 0.001), non-myocarditis aetiology (P = 0.02), higher serum lactates (P = 0.004), epinephrine (but not noradrenaline) use before initiation of ECMO (P = 0.003), haemorrhagic complications (P = 0.001), greater transfusion requirements (P = 0.001) and more severe Survival after Veno-Arterial ECMO (SAVE) and Sonographic Assessment of Intravascular Fluid Estimate (SAFE) scores (P = 0.01 and P = 0.03). CONCLUSIONS: We report the largest focused analysis of VA- and VAV-ECMO recipients in COVID-19. Although relatively rare, the need for temporary mechanical circulatory support in these patients is associated with poor prognosis. However, VA-ECMO remains a viable solution to rescue carefully selected patients. We identified factors associated with poor prognosis and suggest that E-CPR is not a reasonable indication for VA-ECMO in this population.