Markers of platelet activity (P-selectin), fibrinolysis (D-dimer), thrombin activity (prothrombin fragments 1, 2 [PF1,2] and thrombin-antithrombin III complex [TAT]), and inflammation (interleukin 1β [IL-1β]) were measured in 65 patients with mitral stenosis (MS) before and 2 weeks after percutaneous mitral valvotomy (PMV) and in 23 controls. All markers were significantly higher than the control and significantly decreased after PMV. P-selectin change correlated with the changes in left atrial diameter (LAD), pulmonary artery systolic pressure (PASP), and IL-1β. D-Dimer change had similar correlations, LAD, PASP, and IL-1β. The PF1,2 change correlated with the change in IL-1β. The TAT change correlated with the changes in LAD. The IL-1β change correlated with the changes in PASP. In conclusion, MS is associated with heightened inflammatory, platelet, thrombin, and fibrinolytic activities that decrease after PMV. Altered hemodynamics and reduced inflammatory activity might have a possible role in these changes.