Long-Term Outcomes in Patients with Fulminant Myocarditis Supported with Extracorporeal Membrane Oxygenation Surviving to Hospital Discharge.

Purpose: Fulminant myocarditis (FM) is a morbid disease that can progress rapidly to refractory cardiogenic shock requiring venoarterial extracorporeal membrane oxygenation (V-A ECMO). This study aimed to identify long term outcomes in patients with FM who were successfully weaned from V-A ECMO and discharged without durable mechanical circulatory support or heart transplantation (HTx). Methods: This is a retrospective analysis of patient level data of studies identified in a recent systematic review published by our centre on adult patients with FM supported with V-A ECMO. Among the 16 centres that participated (440 patients), we included patients who survived to hospital discharge to evaluate long-term mortality and need for HTx or left ventricular assist device (LVAD). Using a univariable Cox regression model, we also evaluated the association between LVEF at discharge with long-term mortality, HTx or LVAD. Results: Of the 440 patients with FM on V-A ECMO support, 113 were discharged without LVAD or HTx. Average age was 43.4 ± 16.7 years, 42% were male, 26% required CPR pre-ECMO and the average LVEF was 23 ± 11.9% prior to V-A ECMO cannulation. During a median follow-up of 4.4 years (IQR 1.6-7.9), there were 3 deaths, 1 HTx and 1 LVAD. The composite risk of death, LVAD or HTx at 1 year was 3.0% and 6.9% at 5 years. Of the 113 patients, 106 had documented LVEF at discharge. By univariate analysis, LVEF <50% (n=37, 2 deaths) in comparison to LVEF >50% (n=69, 1 LVAD, 1 death) was not associated with increased risk of the composite end point of death, HTx or mortality (HR 2.9, 95%CI 0.19-42.9). Conclusion: Our study suggests low long-term mortality or need for advanced therapy among patients with FM requiring V-A ECMO who survived to hospital discharge. We did not find an increased risk of the composite endpoint regardless of LVEF at the time of discharge.