Premuzic V, et al. - In hemodialyzed patients, researchers determined the incidence of tunneled hemodialysis catheters-related thrombosis based on catheter tip depth and position. They also assessed the influence of other established risk factors responsible for development of central venous thrombosis. All patients with suspected central venous thrombosis were assessed with cat-scan venography. In patients with the catheter tip placed on the vein wall, a higher incidence of central venous thrombosis was reported, which was attributed to catheter tip depth proximal of the right atrium. Inappropriate catheter tip depth and localization resulting in vein stasis were suggested to be the cause of increased factor V Leiden mutation and acIgM values observed in these patients.