International Myocarditis Registry

Myocarditis is an inflammatory heart disease primarily of viral origin that can lead to heart failure and death. Despite an unfavorable long-term outcome and mortality rate as high as 50%, classification, diagnosis, and treatment of myocarditis remains controversial. The gold standard for clinical diagnosis is direct sampling of the heart muscle, which often misses the infected area and thus reliability of the test is questionable. While the cause and clinical presentation of myocarditis are often unclear, inflammation of the heart muscle can be clearly imaged by Cardiovascular Magnetic Resonance Imaging (CMR). Due to recent international consensus on CMR protocol for myocarditis and the unique ability of CMR to visualize cardiac structure, function, and characterize tissue, CMR has become the primary tool for clinical assessment. This study aims to test the accuracy of CMR in the diagnosis of myocarditis and to validate whether CMR acquired in an early stage of myocarditis can provide incremental prognostic information. In order to effectively gather relevant clinical data, an online, multi-centre international registry will be established across twenty different medical institutions. Hypotheses: 1. CMR accurately detects active myocardial inflammation in patients with myocarditis 2. CMR acquired in an early clinical stage of myocarditis provides incremental prognostic information superior to standard clinical diagnostic tools.