Diagnostic and prognostic value of circulating microRNAs in patients with acute chest pain

Objectives To address the diagnostic value of circulating microRNAs (miRNAs) in patients presenting with acute chest pain. Design In a prospective, international, multicentre study, six miRNAs (miR‐133a, miR‐208b, miR‐223, miR‐320a, miR‐451 and miR‐499) were simultaneously measured in a blinded fashion in 1155 unselected patients presenting with acute chest pain to the emergency department. The final diagnosis was adjudicated by two independent cardiologists. The clinical follow‐up period was 2 years. Results Acute myocardial infarction (AMI) was the adjudicated final diagnosis in 224 patients (19%). Levels of miR‐208b, miR‐499 and miR‐320a were significantly higher in patients with AMI compared to those with other final diagnoses. MiR‐208b provided the highest diagnostic accuracy for AMI (area under the receiver operating characteristic curve 0.76, 95% confidence interval 0.72–0.80). This diagnostic value was lower than that of the fourth‐generation cardiac troponin T (cTnT; 0.84) or the high‐sensitivity cTnT (hs‐cTnT; 0.94; both P