The early symptoms of this type of myocarditis are atypical and can manifest as refractory nausea caused by non-gastrointestinal reasons, aside from which acute elevation of serum cardiac troponin I (cTnI) can be detected, and endocardial myocardial biopsy may show collagen fibrosis and lymphocyte inflammation [99]. This evidence concerns the gene TNNI3 and myocarditis.