Effect of hemodialysis on plasma levels of vascular endothelial markers.

Vascular endothelial cell dysfunction is linked to hemostatic abnormalities and accelerated atherosclerosis in patients receiving maintenance hemodialysis (HD). The relationships between pre-dialysis plasma levels of immunoreactive thrombomodulin, von Willebrand factor, tissue factor and its inhibitor were studied, and the effects of HD procedure on these endothelial markers were observed. All the markers were higher in 39 HD patients than in 15 healthy controls (p<0.0001). HD treatment resulted in a 50% increase in tissue factor pathway inhibitor (p<0.0001), but did not influence the other markers. This increment directly correlated with the post-dialysis decrease in diastolic (p=0.011) and mean arterial blood pressure (p=0.039), and the surface area of the dialysis membrane (p=0.007). There were no associations between the increase in tissue factor pathway inhibitor and the amount of fluid removed, dose of enoxaparin, or other HD-specific factors. In conclusion, HD is responsible for an increase in plasma tissue pathway factor inhibitor level. The release of tissue factor pathway inhibitor during HD is not only due to heparin injection but also to the contact between blood and artificial dialysis membrane, and to HD-activated hemodynamic forces.