Association of myocardial and serum miRNA expression patterns with the presence and extent of coronary artery disease: A cross-sectional study

Background: MicroRNA (miRNAs) participate in the pathogenesis of coronary artery disease (CAD).

Objective: To evaluate the expressions of myocardial and serum miRNA-27а, miRNA-133а, and miRNA-203 in CAD patients.

Method: This cross-sectional observational study comprised 100 subjects (60.9 ± 1.0 years; 67% men). The right atrial and serum expressions of miRNA-27a, miRNA -133a, and miRNA-203 in 80 patients referred for elective coronary artery bypass graft surgery (CABG) and 20 control patients scheduled for heart valve surgery were analyzed using real-time polymerase chain reaction.

Results: There was a positive correlation between the SYNTAX score I index and serum miRNA-203 expression level (r = 0.693; p < .001). Patients with ≥3 coronary artery lesions had significantly higher myocardial expressions of miRNA-27a, miRNA-133а, and miRNA-203 than patients with 1-2 vessel disease in the atrial myocardium (miRNA-27a: 234.62 ± 29.51 vs. 182.39 ± 19.62 relative expression unit (REU); miRNA-133а: 127.53 ± 13.41 vs. 111.35 ± 12.31 REU; and miRNA-203: 5.25 ± 0.96 vs. 4.71 ± 0.67 REU; р < 0.05); the same association was found for serum miRNA expressions (miRNA-27a: 11.41 ± 3.85 vs. 4.82 ± 1.82 REU; miRNA-133а: 8.42 ± 2.43 vs. 4.35 ± 1.23 REU; and miRNA-203: 145.71 ± 15.73 vs. 43.70 ± 9.67 REU; р < 0.05). The decision tree method established that the risk of multivessel lesions was increased five-fold if the miRNA-203 serum expression was >101.00 REU (OR, 5.90; 95% CI, 2.34-9.46; p < .001).

Conclusions: Both myocardial and serum miRNA-27а, miRNA-133а, and miRNA-203 expressions are higher in CABG patients than in non-CAD subjects. The serum miRNA-203 expression level corresponds to myocardial expression and is strongly correlated with the extent of coronary atherosclerosis.