Von Willebrand factor (VWF) as a risk factor for bleeding and thrombosis

Abstract

The von Willebrand factor (VWF) is analysed as a bleeding and thrombotic risk marker. When the VWF level is increased, it predicts a thrombotic phenotype and when VWF level is low in plasma, the phenotype varies to bleeding disorder. But it is quite challenging to define when the level is low, normal or high taking into account that these values are capricious and overlap. This matter should be solved by extensive epidemiologic studies. VWD is a hereditary disorder with several described mutations. VWF is a major acute-phase reactant, besides the physiological conditions such as blood group and pregnancy that affect plasmatic VWF levels. Subjects with O blood group have 25% less VWF than those of non O blood groups, and the latter show higher thrombus burden. VWF would be sensitive though not specific diagnostic marker of myocardial infarction. For the assessment of bleeding severity there are special surveys, scores and pictorial charts. The identification of VWF as a thrombotic risk marker has not been clearly established yet, but it has been involved in stroke and coronary disease. We only have the specific replacement therapy for the bleeding phenotype and we can speculate that enoxaparin and PEG-hirudin are able to blunt the VWF rise in patients with unstable angina pectoris and it is associated with a more favourable clinical outcome. Only two questions remain: does VWF as a bleeding risk marker have the same value as a thrombotic risk marker? Will successful treatments like those achieved for bleeding be also possible in the future for thrombosis?

ABO-incompatible kidney transplant recipients have a higher bleeding risk after antigen-specific immunoadsorption

“…The reciprocal also holds true, with a higher incidence of thrombosis in nongroup O individuals . This may be related to the 25% lower levels of von Willebrand Factor in individuals with blood group O vs. non‐O . An argument for a higher bleeding tendency per se in blood group O patients is the nonsignificant higher blood transfusion rate in blood group O ABOc controls and the finding that only blood group O patients received more than one blood transfusion in controls.…”

What is currently known about the genetics of venous thromboembolism at the dawn of next generation sequencing technologies

“…Secreted from activated endothelial cells, von Willebrand factor (VWF) is a key endothelial player participating in both platelet aggregation and the regulation of coagulation FVIII levels in the blood (Vischer, ). Increased plasma levels of VWF are associated with increased risk of VTE (Lazzari et al , ), making any genetic variation controlling the regulation of plasma VWF levels an obvious candidate for VTE. The latest genome‐wide association study (GWAS) for VWF levels revealed 8 loci that are associated with VWF levels (Smith et al , ).…”

Osteoprotegerin Is Associated With Major Bleeding But Not With Cardiovascular Outcomes in Patients With Acute Coronary Syndromes: Insights From the PLATO (Platelet Inhibition and Patient Outcomes) Trial

“…The final addition of novel biomarker GDF‐15 was crucial because this marker has a proven strong association with bleeding outcomes 8. A low circulating level of the endothelial activation marker vWF is a risk factor for bleeding 25. Osteoprotegerin binds vWF with high affinity, and this complex is present in vivo and may influence bleeding risk 2, 3.…”

“…8 A low circulating level of the endothelial activation marker vWF is a risk factor for bleeding. 25 Osteoprotegerin binds vWF with high affinity, and this complex is present in vivo and may influence bleeding risk. 2,3 In addition, osteoprotegerin may bind vWF reductase, thrombospondin-1, and in late stages of thrombus formation, this interaction may promote proteolysis of vWF multimers and prevent platelet aggregation.…”