Association of circulating factor seven activating protease (FSAP) and of oral Omega-3 fatty acids supplements with clinical outcome in patients with atrial fibrillation: the OMEGA-AF study

J Thromb Thrombolysis. 2014 Apr;37(3):317-25. doi: 10.1007/s11239-013-0921-0.


Factor VII Activating Protease (FSAP) activates factor VII (FVII) as well as pro-urokinase (uPA). Our goal was to evaluate the relation between plasma levels of FSAP and clinical instability in atrial fibrillation (AF) and possible effects of oral omega-3 fatty acids (FA) supplements. 101 patients with persistent AF were analyzed in the OMEGA-AF Study. Plasma FSAP levels were measured at baseline and after 12 weeks of treatment with omega-3 FA. The median FSAP antigen concentration, in contrast to FSAP activity, was higher in patients with persistent AF. The maintenance of SR after successful cardioversion (CV) did not lead to a normalization of FSAP concentration. Supplementation with omega-3 FA but not placebo significantly reduced elevated FSAP concentration. Furthermore, elevated FSAP levels did not indicate a significantly increased risk of recurrence of AF after electrical CV or cardiovascular clinical events during 1 year of follow-up. Plasma FSAP concentration was increased in patients with AF and may be involved in the pathogenesis of this condition. The possible effects of omega-3 FA on clinical AF potential could be linked with modulation of circulating FSAP levels.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Atrial Fibrillation / blood*
  • Atrial Fibrillation / diet therapy*
  • Dietary Supplements*
  • Double-Blind Method
  • Fatty Acids, Omega-3 / administration & dosage*
  • Female
  • Follow-Up Studies
  • Humans
  • Male
  • Middle Aged
  • Serine Endopeptidases / blood*


  • Fatty Acids, Omega-3
  • HABP2 protein, human
  • Serine Endopeptidases