Changes in endothelial-related coagulation proteins in response to venous occlusion.

One hundred patients with a history of thrombophilia were divided into two groups based on fibrinolytic response to venous occlusion. Good responders with a euglobulin clot lysis time less than or equal to 105 min showed significant release of tPA, PAI and vWF. Of the poor responders with an ECLT greater than 105 min, 24% showed a subnormal increase in tPA, and a significant proportion of these also showed a reduced or absent rise in vWF. We have shown poor fibrinolytic response was related to either raised levels of PAI, poor release of both tPA and vWF, or poor release of tPA or vWF alone suggesting different mechanisms of fibrinolytic impairment. Protein S levels were not significantly changed in either group following occlusion.