title: Assessing Circulating Factor VIIa-Antithrombin Complexes in Acute Ischemic Stroke: A Pilot Study.
abstract: OBJECTIVE
  The goal of this study was to determine the levels of factor VII (FVII), factor VIIa-antithrombin complexes (FVIIa-AT), total tissue factor (TF), and tissue factor-bearing microparticles (MPs-TF) in patients with acute ischemic stroke. Further, we sought evidence of an association between hemostatic markers, time of blood sampling, type of treatment, and patient outcomes.
  
  
  METHODS
  Venous blood samples were collected from 33 patients on the first day and on the seventh day after stroke diagnosis. Age-matched controls were also included (n = 20). Plasma levels of FVII, FVIIa-AT, total TF, and MPs-TF were measured by enzyme-linked immunosorbent assay. We divided patients into 2 groups: thrombolysis group (n = 13) and nonthrombolysis group (n = 20). Furthermore, evaluation of the National Institutes of Health Stroke Scale and the Barthel Index was performed on the first day and the seventh day.
  
  
  RESULTS
  Patients with ischemic stroke showed significantly lower plasma FVII, FVIIa-AT, and total TF levels than controls (median, 112.25% vs 132.05%, P = .004; 107.97 pmol/L vs 154.94 pmol/L, P < .001; 81.74 pg/mL vs 105.71 pg/mL, P < .001, respectively). In contrast, levels of plasma MPs-TF were significantly higher in patients with stroke compared to healthy controls (1.60 pg/mL vs 0.74 pg/mL, P < .001). Additionally, the thrombolysis group had lower FVII levels on the seventh day compared to the first day (median, 109.80% vs 115.74%, P = .04).
  
  
  CONCLUSIONS
  Factor VII, FVIIa-AT, and total TF are decreased, while MPs-TF are elevated in patients with ischemic stroke. We observed a slight but significant effect of alteplase on FVII plasma levels.
authors.affiliation: 1 Department of Pathophysiology, Nicolaus Copernicus University in Toruń, Ludwik Rydygier Collegium Medicum in Bydgoszcz, Bydgoszcz, Poland.
authors.forename: Artur
authors.initials: A
authors.lastname: Słomka
authors.affiliation: 2 Neurology and Stroke Care Unit, Jan Biziel University Hospital № 2, Bydgoszcz, Poland.
authors.forename: Milena
authors.initials: M
authors.lastname: Świtońska
authors.affiliation: 3 Second Chair of Cardiology, Nicolaus Copernicus University in Toruń, Ludwik Rydygier Collegium Medicum in Bydgoszcz, Poland.
authors.forename: Władysław
authors.initials: W
authors.lastname: Sinkiewicz
authors.affiliation: 1 Department of Pathophysiology, Nicolaus Copernicus University in Toruń, Ludwik Rydygier Collegium Medicum in Bydgoszcz, Bydgoszcz, Poland.
authors.forename: Ewa
authors.initials: E
authors.lastname: Żekanowska
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000990:Antithrombin III / Q000378:metabolism*; D005167:Factor VII / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D020521:Stroke / Q000097:blood*; D015912:Thrombolytic Therapy / Q000379:methods*
chemical_list: D000990:Antithrombin III; D005167:Factor VII
keywords: factor VII; factor VIIa–antithrombin complexes; ischemic stroke; thrombolysis; tissue factor; tissue factor-bearing microparticles