Effects of long-term treatment with warfarin on fibrinogen, FPA, TAT, and D-dimer in patients with coronary artery disease.

Sixty-four patients undergoing aorto-coronary bypass surgery were randomized to receive antithrombotic treatment with acetylsalicylic acid (ASA), 300 mg/d (n = 30) or warfarin, INR = 2.5 - 4.2 (n = 34). The levels of fibrinogen, thrombin-antithrombin III complexes (TAT), fibrinopeptide A (FPA) and D-dimer were assessed before surgery and 9 months postoperatively. In the warfarin treated group the fibrinogen levels were increased after 9 months, while the levels of TAT, FPA and D-dimer were decreased. In the ASA group TAT levels were increased at 9 months, whereas no significant changes in fibrinogen, FPA or D-dimer from baseline were noted. Thus, a reduced activation of the coagulation system has been demonstrated during long-term treatment with warfarin in patients with coronary artery disease.