Expression of miR-223 to predict outcomes after transcatheter aortic valve implantation

Background: Transcatheter aortic valve implantation (TAVI) is an established treatment for aortic stenosis (AS) in patients at increased surgical risk. Up to 29% of patients annually experience major adverse cardiac and cerebrovascular events (MACCE) after TAVI. MicroRNAs (miRNA) are currently widely investigated as novel cardiovascular biomarkers. The aim of this study was to determine the influence of TAVI on the expressions of selected miRNAs associated with platelet function (miR-125a-5p, miR-125b and miR-223), and evaluate the predictive value of these miRNAs for MACCE in 65 patients undergoing TAVI. Methods: Venous blood samples for miRNA expression analysis were collected 1 day before TAVI and at hospital discharge. The expression of miR-223, miR-125a-5p, miR-125b was evaluated in platelet-depleted plasma. Results: The expression of miR-223 and miR-125b increased after TAVI, compared to the measurement before (p = 0.020, p = 0.003, respectively). Among 63 patients discharged from the hospital, 18 patients experienced MACCE (29%) during the median 15 months of observation. Baseline low miR-223 expression was a predictor of MACCE in univariate Cox regression analysis (hazard ratio [HR]: 2.71, 95% confidence interval [CI]: 1.04-7.01; p = 0.041). After inclusion of covariates, age, gender (male), New York Heart Association class and diabetes into the multivariate Cox regression model, miR-223 did not reach statistical significance (HR: 2.56, 95% CI: 0.79-8.33; p = 0.118). Conclusions: To conclude, miR-223 might improve risk stratification after TAVI. Further studies are required to confirm the clinical applicability of this promising biomarker. (Cardiol J 2024; 31, 1: 111-123)