DETERMINATION LEVELS OF miRNA 499A-5P IN PLASMA OF PATIENTS WITH ACUTE MYOCARDIAL INFARCTION.

Background: Acute myocardial infarction(AMI) is the major complication of the coronary artery disease . The successful treatment of AMI patients contributes to the early and accurate diagnosis. Several cardiac biomarker are used in the diagnosis of MI but the ideal biomarker still lacking. Currently, the micro-RNAs are under evaluation which may be a novel biomarker for MI diagnosis Objective: The aim of this study is detection levels of the miRNA499a-5p in plasma of patients with AMI at the time of admission to the emergency unit (symptoms less than 12 hours) and detection utility of the miRNA499a-5p in the early diagnosis of AMI , and whether miRNA499 detect the infarct size or differentiate among PCI group. Method: Seventy patients with AMI, and 20 healthy individuals were subjected to study of plasma miRNA499a-5p levels by qRT-PCR , with the titer of serum cardiac troponin-I. Results: The miRNA499a-5p levels were increased above the cutoff value (P-value is 0.000, O.R= 11.9) in 38.6% of AMI patients group at first hour of admission. Pearson correlation showed that elevated levels of plasma miRNA499 in patients group were highly significant (PV= 0.004) correlated with cardiac troponin ?I , while it non significantly correlated with the positive and negative troponin results (accuracy: 54.3%, OR: 183 with acceptable ROC: 0.667). The elevated results of miRNA499 were linked with 21.4% in the period less than 5 hours of onset chest pain (accuracy: 50% and OR: 0.36 and ROC: 0.564) ,and showed that elevated miRNA499 levels recognized 45.2% of patients with ST-wave, while it was with 33.3 % of NST-patients (accuracy: 57.1% and OR: 1.64 and ROC:0.462), and discriminated 27.3% of patients were subjected to percutaneous coronary intervention(PCI )(accuracy: 45.7% and OR: 1.82 and ROC:0.465). Conclusions: The plasma miRNA499-5p was elevated in AMI patients at the time of admission and positively correlated with the troponin but it unlike troponin-I and cannot detect the infract size, with little diagnostic utility in the first 5 hours after chest pain onset. Elevated levels of miRNA499-5p showed low ability in the differentiation among ECG groups and among PCI groups. suggest that miRNA499-5p is a useful confirmatory biomarker for MI diagnosis and it may has a significant value in the deleterious stages of injury post MI .