Diagnostic value of miR-30d-5p and miR-125b-5p in acute myocardial infarction

Rapid and accurate differential diagnosis of acute myocardial infarction (AMI) is crucial for timely interventions and the improvement of prognosis. However, this is difficult to achieve using current methods. Therefore, the present study aimed to evaluate the suitability of circulating microRNAs (miRNAs) as AMI biomarkers in patients with acute coronary syndrome (ACS). miRNA profiling in plasma samples from patients with AMI (n=3) and healthy controls (n=3) was performed using microarrays. Results were then validated in five patients and five healthy controls. miRNA-125b-5p and miR-30d-5p expression levels were quantified in plasma samples from 230 patients with ACS and 79 healthy controls using reverse transcription-quantitative polymerase chain reaction. Routine diagnostic parameters were assessed, including creatinine kinase MB, cardiac troponin I (cTnI) and myoglobin. A total of 33 miRNAs were differentially expressed in patients with AMI and healthy controls. Following validation based on the previously established roles for these miRNAs, six miRNAs were validated. miR-125b-5p and miR-30d-5p were selected for further investigation. Expression levels of miR-125b-5p and miR-30d-5p in plasma were higher in patients with ACS compared with the healthy controls (P<0.001). Receiver operating characteristic curve analysis revealed that the area under the curve of miR-30d-5p was higher than that of cTnI (0.915 and 0.899). miR-125b-5p (sensitivity, 0.808; specificity, 0.845) and miR-30d-5p (sensitivity, 0.855; specificity, 0.810) were suitable diagnostic predictors of AMI. Kaplan-Meier survival analysis indicated that miR-125b-5p levels were associated with 6 month cardiovascular events in patients with AMI, but not miR-30d-5p. miR-125b-5p and miR-30d-5p presented a diagnostic value for early diagnosis of AMI, and miR-30d-5p may have a higher diagnostic value than cTnI.