Effect of Acute Immunosuppression on Left Ventricular Recovery and Mortality in Fulminant Viral Myocarditis: A Case Series and Review of Literature

Turgeon, Pierre Yves; Massot, Montse; Beaupré, Frédéric; Belzile, David; Beaudoin, Jonathan; Bernier, Mathieu; Bourgault, Christine; Germain, Valérie; Laliberté, Claudine; Morin, Joëlle; Gervais, Philippe; Trahan, Sylvain; Charbonneau, Éric; Dagenais, François; Sénéchal, Mario

BACKGROUND: Fulminant viral myocarditis (FVM) is a rare cause of cardiogenic shock associated with high morbidity and mortality rates. An inappropriately activated immune system results in severe myocardial inflammation. Acute immunosuppressive therapy for FVM therefore gained in popularity and was described in numerous retrospective studies. METHODS: We conducted an extensive review of the literature and compared it with our single-centre retrospective review of all cases of FVM from 2009-2019 to evaluate the possible effect of acute immunosuppression with intravenous immunoglobulins and/or high dose corticosteroids in patients with FVM. RESULTS: We report on 17 patients with a mean age of 46 ± 15 years with a mean left ventricular ejection fraction (LVEF) of 15 ± 9% at admission. Fourteen (82%) of our patients had acute LVEF recovery to ≥ 45% after a mean time from immunosuppression of 74 ± 49 hours (3.1 days). Extracorporeal membrane oxygenation (ECMO) was required in 35% (6/17) of our patients for an average support of 126 ± 37 hours. Overall mortality was 12% (2/17). No patient needed a long-term left ventricular assist device or heart transplant. All surviving patients achieved complete long-term LVEF recovery. CONCLUSIONS: Our cohort of 17 severely ill patients received acute immunosuppressive therapy and showed a rapid LVEF recovery, short duration of ECMO support, and low mortality rate. Our suggested scheme of investigation and treatment is presented. These results bring more cases of successfully treated FVM with immunosuppression and ECMO to the literature, which might stimulate further prospective trials or a registry.