title: Clopidogrel has no effect on D-dimer and thrombin-antithrombin III levels in patients with peripheral arterial disease undergoing peripheral percutaneous transluminal angioplasty.
abstract: OBJECTIVE
  Coagulation activation markers are significantly elevated in patients with peripheral arterial disease compared with healthy controls. The more severe the disease, the higher the markers. Increased coagulation activation may contribute to the disease process and the risk of complications in patients with peripheral arterial disease, particularly after endovascular intervention. Animal studies have shown that clopidogrel significantly inhibits coagulation activation. The aim of this study was to determine whether combination of aspirin and clopidogrel affects thrombin-antithrombin III and D-dimer in patients with intermittent claudication undergoing angioplasty, compared with aspirin alone.
  
  
  METHODS
  This was a double blind, randomized placebo-controlled trial conducted in a vascular unit in a tertiary referral center. One hundred thirty-two patients with intermittent claudication were randomized to clopidogrel and aspirin or placebo and aspirin, with a loading dose 12 hours before endovascular intervention. D-dimer and thrombin-antithrombin III (TAT) levels were measured using enzyme-linked immunosorbent assay at baseline, 1 hour before, and 1 hour, 24 hours, and 30 days after intervention in 103 patients who underwent endovascular intervention.
  
  
  RESULTS
  There was a significant rise in D-dimer levels at 1 hour and 24 hours after angioplasty in both groups (placebo group: 63.69, 141.45, 122.18 ng/mL; clopidogrel group: 103.79, 159.95, 134.69 ng/mL), but no difference between the two groups (P = .514). Similarly there was a significant rise in TAT levels at 1 hour after angioplasty in both groups (placebo group: 2.93, 6.16 microg/L; clopidogrel group: 3.39, 5.27 microg/L), with no significant difference between the two groups (P = .746).
  
  
  CONCLUSIONS
  Endovascular intervention results in a significant increase in TAT and D-dimer. The addition of clopidogrel to aspirin has no effect on TAT and D-dimer before or after endovascular intervention.
authors.affiliation: Department of Vascular Surgery, University of Aberdeen, Scotland, United Kingdom. k.cassar@abdn.ac.uk
authors.forename: Kevin
authors.initials: K
authors.lastname: Cassar
authors.forename: Paul
authors.initials: P
authors.lastname: Bachoo
authors.forename: Isobel
authors.initials: I
authors.lastname: Ford
authors.forename: Mike
authors.initials: M
authors.lastname: Greaves
authors.forename: Julie
authors.initials: J
authors.lastname: Brittenden
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000800:Angioplasty, Balloon; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology / Q000627:therapeutic use; D000990:Antithrombin III; D001241:Aspirin / Q000494:pharmacology / Q000627:therapeutic use; D000077144:Clopidogrel; D004311:Double-Blind Method; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000032:analysis*; D006801:Humans; D007383:Intermittent Claudication / Q000097:blood* / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D010447:Peptide Hydrolases / Q000097:blood*; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use; D013988:Ticlopidine / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D005338:Fibrin Fibrinogen Degradation Products; D010975:Platelet Aggregation Inhibitors; C046193:antithrombin III-protease complex; C036309:fibrin fragment D; D000990:Antithrombin III; D000077144:Clopidogrel; D010447:Peptide Hydrolases; D013988:Ticlopidine; D001241:Aspirin