Statins have been demonstrated to significantly affect the prognosis and outcome of patients with cardiac diseases. Several studies have suggested pleiotropic effects of the statins in these patients. The present study was designed to examine the effects of atorvastatin on inflammation, endothelial function, cardiac performance and exercise tolerance in patients with idiopathic dilated cardiomyopathy (IDCM). Sixty-four patients with IDCM were divided randomly into an atorvastatin treatment group (atorvastatin 10 mg/d orally) and a placebo control group. Before and 12 weeks after the treatment, circulating soluble intercellular adhesion molecule-1 (sICAM-1), Von Willebrand factor (vWF) and C-reactive protein (CRP) levels were detected using enzyme-linked immunosorbent assay (ELISA); Flow-mediated dilatation (FMD) of the brachial artery was measured, and left ventricular ejection fraction (LVEF) and the 6-min walk test (6MWT) evaluated. After atorvastatin treatment, LVEF increased from 34.5 +/- 5.7% to 41.4 +/- 4.5% (P < 0.05), and from 32.8 +/- 4.0% to 36.9 +/- 5.2% (P < 0.05) in the placebo group. Also, the distances covered in the 6MWT increased from 358 +/- 61 m to 431 +/- 66 m in the atorvastatin group, and from 351 +/- 70 m to 382 +/- 74 m in the placebo group (both p < 0.05 vs. baseline). The increases in LVEF and 6MWT distances were significantly greater in the atorvastatin than in the placebo group. sICAM-1, CRP and vWF levels decreased and FMD increased significantly in the atorvastatin group, but not in the control group. Correlation analysis showed that the baseline sICAM-1 level was positively correlated with plasma CRP and vWF levels (r = 0.554 and 0.628, respectively); FMD was inversely correlated with serum sICAM-1 and plasma vWF levels (r = -0.579 and -0.590, respectively) and positively correlated with LVEF and distance attained in 6MWT (r = 0.536 and 0.522, respectively). Twelve weeks of treatment with atorvastatin significantly decreased serum sICAM-1, CRP and vWF levels, and improved the FMD, LVEF and 6MWT outcomes. Inhibition of inflammation, alleviating endothelium damage and endothelial dysfunction might comprise part of the underlying mechanisms leading to the improvement of LV function and exercise tolerance in patients with IDCM.