It has been demonstrated that rheumatic mitral valve stenosis (PMVS) is associated with an increase in markers of endothelial dysfunction. It is not known whether this association indicates an impairment of flow-mediated dilatation (FMD) of the vascular endothelium. Thirty patients with RMVS and 30 healthy subjects were studied. FMD in patients with RMVS was significantly smaller than in healthy controls (11.9 +/- 0.4% vs 15.4 +/- 0.70%, p=0.003). The absolute change in brachial artery diameter in patients with RMVS was also significantly smaller than in healthy subjects (0.42 +/- 0.26 mm vs 0.64 +/- 0.32 mm, p < 0.001). These findings suggest that vascular endothelial function is altered in patients with RMVS. (c) 2007 Elsevier Ireland Ltd. All rights reserved.