title: Exercise in claudicants is accompanied by excessive thrombin generation.
abstract: BACKGROUND
  exercise in IC leads to ischaemia-reperfusion injury of leg muscles and a systemic inflammatory response, but the effect of on coagulation is unknown.
  
  
  OBJECTIVE
  to compare the effect of exercise on thrombin formation and fibrin turnover in patients with IC (n = 10), and age and sex matched smokers ([S] n = 5) and non-smokers ([NS] n = 5) without peripheral vascular disease.
  
  
  METHODS
  blood was taken from subjects 60 and 30 min before, and 1, 5, 20, 40, 60 and 120 min after, treadmill exercise. Markers of thrombin generation (thrombin-antithrombin complexes [TAT] and prothrombin fragments 1 + 2 [PF1 + 2]) and fibrin turnover (D-dimer and fibrin degradation products [FbDP]) were assayed at each time point.
  
  
  RESULTS
  following exercise, thrombin generation was significantly greater in the claudicant group compared to the control groups (Area Under Curve [AUC] post exercise IC vs S vs NS; TAT 3960 vs 1623 vs 1476 vs = 0.007 Kruskal-Wallis [KW]; PF1 + 2 163 vs 107 vs 123 p = 0.024 KW). Pre and post-exercise, fibrin turnover in claudicants was similar to smoking controls, but higher than non-smoking controls. (AUC post exercise IC vs NS; D-dimer 6340 vs 2754 p = 0.055 Mann-Whitney U[MW]; FbDP 45113 vs 21511 p = 0.009 MW).
  
  
  CONCLUSIONS
  when compared to non-claudicants, exercise in IC is associated with excessive production of thrombin. Despite this, claudicants have a similar level of fibrin turnover suggesting a possible defect in fibrinolysis. This prothrombotic state may contribute to the excess thrombotic morbidity and mortality suffered by claudicants.
authors.affiliation: University Department of Vascular Surgery, Birmingham Heartlands Hospital, Bordesley Green East, Birmingham B9 5SS, UK.
authors.forename: P
authors.initials: P
authors.lastname: Burns
authors.forename: T
authors.initials: T
authors.lastname: Wilmink
authors.forename: C
authors.initials: C
authors.lastname: Fegan
authors.forename: A W
authors.initials: AW
authors.lastname: Bradbury
mesh_terms: D000368:Aged; D015444:Exercise; D005337:Fibrin / Q000378:metabolism; D005342:Fibrinolysis; D006801:Humans; D007383:Intermittent Claudication / Q000097:blood / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D012907:Smoking / Q000503:physiopathology; D013917:Thrombin / Q000096:biosynthesis*
chemical_list: D005337:Fibrin; D013917:Thrombin