The study population consisted of 16 patients with rheumatic mitral stenosis undergoing percutaneous transluminal mitral valvuloplasty (group 1). The plasma levels of tumor necrosis factor-α (TNF-α) and interleukin-10 (IL-10) in the femoral vein and the right and left atria before valvuloplasty were determined by ELISA. Additionally, we measured plasma concentrations of TNF-α and IL-10 in the venous blood obtained from 19 control patients, including 12 healthy volunteers in sinus rhythm (group 2) and 7 patients in permanent lone atrial fibrillation (group 3). The venous plasma levels of TNF-α were significantly elevated in group 1 patients compared with group 2 patients (p < 0.002). Correlation analysis demonstrated that there was a significantly direct relationship between the plasma TNF-α and IL-10 concentrations in the left atrial, right atrial and peripheral venous blood (p < 0.008, r = 0.640; p < 0.04, r = 0.538; p< 0.03, r = 0.571, respectively). In conclusion, the plasma concentrations of TNF-α of patients with rheumatic mitral stenosis were significantly higher than those of healthy volunteers. In addition, there was a significantly direct relationship between the soluble TNF-α and IL-10 concentrations in the atrial and peripheral venous blood, indicating a balance between circulating TNF-α and IL-10 levels in patients with rheumatic mitral stenosis.