The effect of an 8-week treatment with either ramipril or placebo is studied using a randomized, double-blind, and crossover protocol. After given written informed consent, baseline characteristics including physical examination, ECG, blood sample and a noninvasive assessment of endothelial function are obtained. The patients are randomly assigned to receive either ramipril 10mg (up-titration-scheme: starting with 2.5mg in Week1, then 5mg in Week2 followed by 2-5mg for the final 6 weeks) followed by placebo or vice versa.The individual disease-modifying antirheumatic drug therapy is continued throughout the study. The examinations are repeated after 8 weeks treatment of the first and 8 weeks after the second study drug. At week 1 and 2 in each treatment period a safety visit is scheduled.