Aortic stenosis (AS) is a progressive valvular heart disease characterized by fibrocalcific remodeling, inflammation, and hemodynamic disturbances. Serum biomarkers may indirectly reflect these processes. Autotaxin (ATX) and lysophosphatidic acid (LPA) have been implicated in osteogenic differentiation of valvular interstitial cells, while growth differentiation factor-15 (GDF-15) reflects cellular stress and vascular changes. Thrombomodulin (TM) indicates endothelial injury and interacts with thrombin. This study aimed to evaluate biomarkers focusing on serum ATX, LPA, GDF-15, and TM levels and flow-mediated dilatation (FMD) in patients with AS. Overall, 149 patients were included in the study: 86 consecutive patients with AS hospitalized due to qualification for invasive treatment of AS and 63 controls. The clinical characteristics, echocardiographic data, FMD, and the following biomarkers-ATX, LPA, GDF-15, and TM-were included in the analysis. AS patients presented increased serum levels of ATX, GDF-15, and TM as compared to the controls. Differences in LPA levels were not statistically significant. FMD values were significantly lower in AS patients. The biomarkers mentioned above and FMD correlated with AS severity. There were no differences in both biomarkers' serum levels and FMD regarding the hemodynamic AS phenotype. GDF-15 serum level was a risk factor for all-cause mortality and MACCE in the 12-month follow-up.