Measurement of plasma biomarkers The prognostic value of plasma biomarkers such as CRP, troponin I, proinflammatory cytokines (e.g. IL-6, IL18 and others) in patients with acute pericarditis will be investigated. The value of micro-RNAs (miRNAs) as candidate biomarkers involved in the pathogenesis of acute pericarditis will be also sought in gene expression studies.