The severity of atherosclerosis is associated with fibrinogen and degradation of cross-linked fibrin

Abstract

To assess the extent of thrombin formation and local fibrinolysis in atherosclerosis, we studied 40 patients with peripheral arterial occlusive disease. Since the patients (age 64 ± 2 years) had not undergone any vascular interventions their disease represents the natural occurrence of atherosclerosis. Only patients whose symptoms had been stable for the past three months were included to eliminate recent thrombotic events. The severity of the disease was assessed with ankle/brachial blood pressure index (ABI). The plasma thrombin-antithrombin III complexes were within normal limits thus excluding ongoing thrombosis. However, stabilized fibrin-originated D-dimer was significantly elevated (541–770, 95% confidence interval, normal < 400 ng/ml). Since the mean ABI and D-dimer levels correlated strongly (R: 0.57, p < 0.0001), our study indicates that progressive peripheral atherosclerosis is associated with degradation of local cross-linked fibrin. Also, both functional and immunonephelometrically-assessed fibrinogen correlated with the severity of the disease (R: 0.57, p < 0.0002). Our in vivo data support the autopsy evidence that as an expression of an active fibrinolytic system ongoing degradation of cross-linked fibrin is involved in progressive atherosclerosis.