Aims: A prothrombotic state with elevated levels of soluble P-selectin (sP-sel), fibrinogen, von Willebrand factor (vWf), and other haemostatic indices has been reported in some patients with atrial fibrillation (AF). Whether these changes are due to AF itself or coexistent cardiovascular diseases remains a matter of debate. Therefore, in the present study, the differences in plasma levels of sP-sel, fibrinogen, and vWf between patients with idiopathic/lone AF and sex-, age-, and risk factor-matched controls were investigated to determine whether AF itself might be associated with a hypercoagulable state.
Methods and results: Ninety consecutive patients (63 males, 54.1 ± 10.1 years) with idiopathic AF were studied, 60 (43 males, 48.8 ± 7.5 years) of whom were diagnosed as lone AF. Plasma sP-sel and vWf were measured by enzyme-linked immunosorbent assay. Plasma fibrinogen was measured by chromometry. These indices in AF patients were compared with those in sex-, age- and risk factor-matched controls. Compared with the controls, patients with idiopathic AF had higher levels of sP-sel (AF vs. control: 33.4 ± 7.4 vs. 29.2 ± 6.5 ng/mL, P < 0.001) and fibrinogen (AF vs. control: 3.3 ± 0.9 vs. 3.0 ± 0.6 g/L, P = 0.02), but not vWf, whether with the adjustment of covariates or not. As for those < 60 years, between lone AF and age-matched controls, significant difference existed in the levels of sP-sel (AF vs. control: 34.5 ± 7.3 vs. 30.2 ± 7.3 ng/mL, P = 0.002), but not in those of fibrinogen and vWf, whether with the adjustment of covariates or not.
Conclusions: Both platelet activation and abnormal changes in coagulation were suggested in idiopathic AF and a platelet activation state in lone AF. This supports the notion that AF per se contributes to a state of hypercoagulation.