Background: The aim of this study was to compare the influence of 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors on endothelial function and blood pressure in patients with essential hypertension on long-term angiotensin-converting enzyme inhibitor therapy. Method: The study was designed as a prospective, double-blind, randomised, placebo controlled, crossover clinical trial. Twenty patients with essential hypertension were treated with an angiotensin-converting enzyme inhibitor; the control group included 10 healthy subjects. Hypertensive patients received in random order 80 mg of fluvastatin daily or placebo for 6 weeks. The following parameters were assessed at baseline and after each treatment period: serum lipids, flow-mediated vasodilation, activity of von Willebrand factor, concentration of vascular endothelial growth factor, C-reactive protein and 24-hour blood pressure profile. Results: Hypertensive patients did not differ from healthy subjects with respect to age, body mass and biochemical parameters, with the exception of C-reactive protein, which was higher in hypertensive patients ( P=0.02). After statin therapy, low-density lipoprotein cholesterol ( P<0.0001), C-reactive protein ( P=0.03), von Willebrand factor ( P=0.03) and vascular endothelial growth factor ( P<0.01) decreased and flow-mediated vasodilation improved ( P<0.001). Statins had no significant effect on blood pressure. Conclusions: Statins added to angiotensin-converting enzyme inhibitors may improve endothelial function and ameliorate inflammation independently of blood pressure.