Global surveillance of circulating microRNA for diagnostic and prognostic assessment of acute myocardial infarction based on the plasma small RNA sequencing.

Background: Circulating microRNAs (miRNAs) are recently a rapidly increasing of interest as non-invasive biomarkers for diagnosis and prognosis of acute myocardial infarction (AMI). Previous studies revealed that several miRNAs exhibited the capacity for diagnosis and prognosis of AMI, the reasons why these circulating miRNAs are concerned as targets for investigation are quite cryptogenic, presumably due to the lack of clues provided by global surveillance at the transcriptome level, and the current data for some miRNAs are controversial and inconsistent among independent studies.

Methods: To comprehensively profiling the potential miRNAs for diagnosis and prognosis of AMI, we reported transcriptomes of circulating miRNAs in the plasma of 27 healthy controls, 64 AMI patients (37 STEMI and 27 NSTEMI) and 20 AMI patients who were subjected to reperfusion therapy. Meanwhile, the cTnI of AMI patients was parallel determined. Differentially-circulated miRNAs were analyzed between each group. All detected circulating miRNAs were examined by ROC analysis and then LASSO dimension reduction to obtain an optimal panel for diagnosis of AMI. A five-year period follow-up towards the AMI and reperfusion patients was performed, and the prognostic value of circulating miRNAs in these patients was estimated by using the Cox regression model, ROC and Kaplan-Meier curves.

Results: Comprehensive global differences of miRNAs transcriptome among AMI, reperfusion patients and healthy controls were identified. A total of 40 miRNAs, called high diagnostic performance miRNAs, including several previous well-studied miRNAs with AUC greater than 0.85 were shown to discriminate AMI with healthy controls. In addition, 29 miRNAs were analyzed to be strongly correlated with the plasma cTnI level, of which 20 overlapped with high diagnostic performance miRNAs. These overlapped miRNAs are over-represented in the pathways which actually reflect the pathological cause of myocardial infarction, as well as the regulation of gene expression and energetic pathway of cellular response to hypoxia. Finally, two miRNAs were analyzed to be significantly correlated to all-cause mortality.

Conclusion: This is the first time to survey plasma miRNAs for the development of AMI diagnostic and prognostic biomarkers at the transcriptome level. A subset of miRNAs exhibited potential diagnostic and prognostic merits for AMI.