[Changes of endothelial function indices and their relation to platelet activation in idiopathic atrial fibrillation].

Objective: To investigate the changes of endothelial function indices and their relation to platelet activation in patients with idiopathic atrial fibrillation (AF).

Methods: We studied 61 patients with idiopathic AF with 34 age- and sex-matched healthy persons as control. Platelet counts in the blood were tested, and plasma levels of NOx were analyzed using Griess method. The plasma levels of von Willibrand factor (vWF) and soluble P-selectin (sP-selectin) were determined using enzyme-linked immunosorbent assay.

Results: Compared to healthy control, the patients with idiopathic AF had significantly lower levels of plasma NOx (18.2-/+7.3 vs 24.3-/+7.8 micromol/L, P=0.049) and higher levels of plasma sP-selectin (25.6-/+6.2 vs 22.4-/+4.8 ng/ml, P=0.007). No significant differences were found in the platelet counts or plasma vWF levels between the two groups. A significant inverse correlation was found between plasma NOx and sP-selectin (r=-0.405, P=0.025) in patients with idiopathic AF.

Conclusion: AF per se may impair the endothelial function and activate platelet function, suggesting the role of endothelial dysfunction in activated platelet function in AF patients.