Evaluating Diagnostic and Prognostic Value of Plasma miRNA133a in Acute Chest Pain Patients Undergoing Coronary Angiography

Circulating microRNA has recently emerged as a promising biomarker for cardiovascular disease. This study sought to evaluate the diagnostic and prognostic value of circulating miR-133a as a marker of acute myocardial infarction in acute chest pain patients undergoing coronary angiography. Plasma was collected from 312 patients with chest pain on admission in the emergency department and 67 healthy controls. MiR-133a was detected using real-time quantitative PCR and enhanced accu-TnI, creatinine kinase-MB mass, and myoglobin were measured by immunoassay. End-point events (serious adverse cardiovascular events which require hospitalization or cardiovascular death) were examined in the AMI (acute myocardical infarction) group within 1, 6, 12, and 24 months. The miR-133a level was higher in AMI patients than in non-AMI patients (P < 0.001). In the ROC analysis, the sensitivity of miR-133a in diagnosis of AMI is 0.61 and the specificity is 0.68. In the prognostic analysis, only 1 endpoint event was observed in the non-AMI group; the amount of cases with end-point events in the AMI group at 1,6,12, and 24 months were 8, 19, 28, and 35, respectively. The cutoff value of miR-133a was determined using the median value of the AMI group and separated the patients into a positive group and a negative group. The Kaplan–Meier survival curve showed no significant difference in survival was detected in AMI patients between the miR-133a positive group and negative group after follow-up (12-month: x2 = 1.353, P = 0.245; 24-month: x2 = 3.722, P = 0.054). After adjusting for age, gender, Killip classes, prior myocardiac infarction history, myoglobin, LVEF (left ventricular ejection fraction), diabetes, hypertension, smoking and systolic blood pressure, miR133a had a significant association with the risk of events at 12 months (HR = 2.869, P = 0.024) and 24 months (HR = 3.936, P = 0.001). In patients undergoing coronary angiography, circulating miR-133a is upregulated in AMI patients, but it does not provide enough accuracy for clinical AMI diagnosis because it also rises in unstable angina patients. Its prognostic value in AMI is uncertain mainly for the number of cases with end-point event was small and may be further validated in a larger, better designed study.