Circulating miRNA-155 as a Potential Biomarker for Coronary Slow Flow

OBJECTIVE: Recent studies have demonstrated that miRNA-155 is involved in the occurrence and development of atherosclerosis. Furthermore, miRNA-155 has emerged as a new indirect marker for inflammation associated with adverse outcomes in oncology and cardiovascular diseases. This study investigated the correlation between the levels of miRNA-155 and coronary slow flow (CSF). METHODS: A total of 66 patients with CSF and 66 patients with normal coronary flow were enrolled in this study. Coronary flow velocity was determined using the thrombolysis in myocardial infarction frame count (TFC) method. The plasma levels of miRNA-155 were quantified using real-time quantitative polymerase chain reaction. RESULTS: The plasma levels of miRNA-155 were significantly higher in the CSF group compared to the control group (P < 0.05). In addition, miRNA-155 levels were positively correlated with TFC and high-sensitivity C-reactive protein (hs-CRP) levels (P < 0.05 for both parameters). Multivariate linear regression analysis demonstrated that plasma miRNA-155 (OR = 2.384, 95% confidence interval 1.847–3.273, P = 0.032) and hs-CRP (OR = 1.273, 95% confidence interval 1.036–2.253, P = 0.013) were independent predictors for CSF. Using plasma miRNA-155 levels as the test variable, ROC curve analysis indicated that the area under the curve was 0.782 (P < 0.05). CONCLUSION: Patients with CSF have higher plasma levels of miRNA-155, and this may play an important role in the pathogenesis of CSF, and an elevated plasma miRNA-155 level may be a predictor for CSF. A large-scale and multicenter study is required to elucidate the role of miRNA-155 as a potential biomarker for patients with CSF.