Factor VII in subjects at risk for thromboembolism: activation or increased synthesis?

In this study the preliminary results obtained by investigating factor VII antigen and activity in 38 subjects with arterial disease of the extremities are reported. The antigen determination (VII:Ag) was performed by using an inhibitor neutralization assay; factor VII activity (VII:C) was determined by one-stage assay with human factor VII artificially depleted plasma. All the patients showed increased levels of VII:C and VII:Ag compared to the reference population (p less than 0.001). There is a significant correlation between VII:C and VII:Ag (r = 0.47), but the ratio VII:C/VII:Ag is slightly increased. Our results confirm that elevated levels of factor VII are present in patients with tendency to thrombosis.