Study to Evaluate the Efficacy of Immunosuppression in Myocarditis or Inflammatory Cardiomyopathy.

Myocarditis can result in numerous complications, but there is paucity of data regarding optimal therapy, short- and long-term effects of possibly effective immunosuppressive therapy. The IMPROVE-MC study will provide high-quality scientific data about efficacy and safety of immunosuppressive therapy, non-invasive (MRI, biomarkers) and invasive diagnostics tests (endomyocardial biopsy), and prognosis in myocarditis. The objective of this multicenter, prospective, randomized, double-blind placebo-controlled trial is to assess the efficacy and safety of 12 - month treatment with prednisone and azathioprine comparing to placebo on top of guideline-recommended medical therapy in patients with biopsy-proven virus negative myocarditis or inflammatory cardiomyopathy and reduced ejection fraction (LVEF ≤ 45%). The study will also assess persistence of the treatment effects after 12 months.