Epidemiology characteristics and outcome of patients with clinically diagnosed acute myocarditis

Acute myocarditis is an inflammatory disease of the myocardium most often resulting from a viral infection or autoimmune disorders.1,2 Among the other potential causes myocarditis can be due to hypersensitivity reactions,3 or to the inhibition of immune checkpoints.4,5 Post mortem examinations in young adults have demonstrated that acute myocarditis was responsible of 3-12% of cases of sudden cardiac death.6,7 As most previous studies of acute myocarditis comprised a relatively small patient population (100 to 200) with variable timing of diagnosis from symptom onset,8,9 the in-hospital as well as long term outcomes of patients with clinically suspected acute myocarditis remains to be determined.