VWF and Venous thrombosis: While there was no difference in VWF:Ag and VWF:pp between patients who developed bleeding and those with thrombosis (Figures 4A and 4B), the VWF:pp-to-VWF:Ag ratio was greater in patients with bleeding than those with thrombosis (Figure 4C), suggesting a higher degree of endothelial activation in bleeding patients, consistent with the in vitro findings (Figures 1C and 1D).