title: Factor VIIa-antithrombin complexes in patients with arterial and venous thrombosis.
abstract: Antithrombin (AT), in the presence of heparin, is able to inhibit the catalytic activity of factor VIIa bound to tissue factor (TF) on cell surfaces. The clinical meaning of FVIIa-AT complexes plasma levels is unknown. It was the objective of this study to evaluate FVIIa-AT complexes in subjects with thrombosis. Factor VIIa-AT complexes plasma levels in 154 patients consecutively referred to our Department with arterial or venous thrombosis and in a group of 154 healthy subjects, were measured. Moreover, FVIIa-AT complexes were determined in: i) n = 53 subjects belonging to 10 families with inherited factor VII deficiency; ii) n = 58 subjects belonging to seven families with AT deficiency; iii) n = 49 patients undergoing oral anticoagulant therapy (OAT). Factor VIIa-AT levels were determined by a specific ELISA kit (R&D, Diagnostica Stago, Gennevilliers, France). Factor VIIa-AT complexes mean plasma levels were lower in patients with either acute arterial (136 +/- 40 pM) or venous (142 +/- 53 pM) thrombosis than subjects with previous thrombosis (arterial 164 +/- 33 pM and venous 172 +/- 61 pM, respectively) and than healthy controls (156 +/- 63 pM). Differences between acute and previous thrombosis, were statistically significant (p < 0.05). Subjects with inherited and acquired (under OAT) factor VII deficiency had statistically significant lower FVIIa-AT complexes plasma levels (80 +/- 23 pM and 55 +/- 22 pM, respectively) than controls (150 +/- 51 pM, p < 0.0001 and 156 +/- 63 pM, p < 0.00001, respectively). Factor VIIa-AT complexes are positively correlated with plasma factor VII/VIIa levels. Further investigations are needed to verify the possible role of higher FVIIa-AT complex plasma levels in predicting hypercoagulable states and thrombosis.
authors.affiliation: Department of Cardiologic, Thoracic, and Vascular Sciences, 2nd Chair of Internal Medicine, University of Padua Medical School, Padua, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Spiezia
authors.forename: Valeria
authors.initials: V
authors.lastname: Rossetto
authors.forename: Elena
authors.initials: E
authors.lastname: Campello
authors.forename: Sabrina
authors.initials: S
authors.lastname: Gavasso
authors.forename: Barry
authors.initials: B
authors.lastname: Woodhams
authors.forename: Daniela
authors.initials: D
authors.lastname: Tormene
authors.forename: Paolo
authors.initials: P
authors.lastname: Simioni
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000991:Antithrombins / Q000235:genetics / Q000378:metabolism*; D020147:Coagulation Protein Disorders / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D005165:Factor V / Q000378:metabolism; D015942:Factor VIIa / Q000235:genetics / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D046912:Multiprotein Complexes / Q000378:metabolism*; D011485:Protein Binding; D020246:Venous Thrombosis / Q000097:blood / Q000235:genetics / Q000378:metabolism*
chemical_list: D000991:Antithrombins; D046912:Multiprotein Complexes; D005165:Factor V; D015942:Factor VIIa