Plasma microRNA-21 is a potential diagnostic biomarker of acute myocardial infarction

OBJECTIVE: Previous studies have demonstrated that microRNA-21 (miR-21) is involved in the pathogenesis of myocardium infarction and cardiac fibrosis; the present study aimed to investigate its potential role in the diagnosis of acute myocardium infarction (AMI). PATIENTS AND METHODS: A cohort of patients with AMI and angina pectoris (AP) were studied, plasma miR-21 level was determined by Realtime-PCR. RESULTS: We found that the plasma miR-21 level was significantly elevated in patients with AMI compared with those with AP or healthy people. Further studies demonstrated the correlation of miR-21 and several traditional markers such as creatine kinase (CK), creatine kinase-MB (CK-MB) and troponin I (cTnI) in study subjects. Finally, receiver-operator characteristic curve (ROC) analysis showed that miR-21 has similar diagnostic ability compared with CK, CK-MB and cTnI. CONCLUSIONS: Plasma miR-21 may be a novel biomarker for the diagnosis of AMI. Our study may also provide implications for the development of new biomarkers.