Introduction: Myocardial infarction with non-obstructive coronary arteries (MINOCA) poses a challenge for diagnosis and treatment because of its heterogeneous etiology. The mechanisms underlying MINOCA are diverse and include plaque disruption, coronary spasm, microvascular dysfunction, and thromboembolism. However, the specific molecular pathways involved are not fully understood. MicroRNAs (miRNAs) are known as potential biomarkers and regulators of various cardiovascular diseases. In our study, we aimed to investigate the relationship between MINOCA and exosomal miRNA expression and to determine the potential of these exosomal miRNAs as biomarkers for prognosis, diagnosis, and treatment. Materials and Methods: Three groups were included in the study: 1) the MINOCA group, 2) the myocardial infarction with obstructive coronary artery disease (MI-CAD) group, and 3) the healthy control group. Exosomal miRNA isolation was performed from all participants, and the expression levels of hsa-miR-16-5p, hsa-miR-92a-3p, hsa-miR-487a-5p, and hsa-miR-490-3p were analysed by quantitative real-time PCR (polymerase chain reaction). ΔΔCt values were determined, and statistical analyses were performed after these values were obtained. Results: Statistical analysis of hsa-miR-16-5p, hsa-miR-92a-3p, hsa-miR-487a-5p, and hsa-miR-490-3p revealed that the expression levels of hsa-miR-490-3p were significantly different between the groups in the MINOCA group (p=0.022). hsa-miR-16-5p was found to be closely related to the statistical significance level (p=0.078). hsa-miR-92a-3p and hsa-miR-487a-5p were not significantly different between the groups. Conclusion: Our study revealed that miR-490-3p, which was detected at a statistically significant level in the MINOCA group, is an effective biomarker in MINOCA patients. This miRNA has been reported in only a few studies on myocardial infarction, and our study is the first to report it in relation to MINOCA. The fact that hsa-miR-16-5p is close to statistical significance, whereas statistical significance was not detected for hsa-miR-92a-3p and hsa-miR-487a-5p, indicates that studies with a larger number of individuals are needed.
Yalcintepe et al. (Thu,) studied this question.