title: Platelet activation is increased in peripheral arterial disease.
abstract: OBJECTIVE
  Platelet activation was assessed in patients with peripheral arterial disease compared with healthy control subjects.
  
  
  METHODS
  This prospective comparative study included 100 subjects: 40 consecutive patients with intermittent claudication, 20 consecutive patients with critical ischemia and tissue loss, and 40 healthy control subjects. Whole blood flow cytometric analysis was performed to determine resting and stimulated platelet P-selectin expression and resting and stimulated platelet fibrinogen binding. Results are presented as platelet percentage and also as mean fluorescence intensity.
  
  
  RESULTS
  P-selectin expression was significantly increased in patients with intermittent claudication (median, 0.85%; range, 0.31%-4.77%; P =.023) and critical ischemia (median, 1.11%; range, 0.2%-3.26%; P =.028) compared with control subjects (median, 0.59%; range, 0.16%-4.58%). The percentage of platelets binding fibrinogen was also significantly higher in patients with intermittent claudication (median, 2.89%; range, 1.08%-9.59%; P <.001) compared with control subjects (median, 1.57%; range, 0.17%-10.7%). There was no significant difference in percentage of platelet fibrinogen binding between control subjects and patients with critical ischemia. Fibrinogen binding by stimulated platelets was significantly diminished in patients with critical limb ischemia compared with control subjects (67.2% vs 77.9%; P =.006).
  
  
  CONCLUSIONS
  Platelet activation is increased in patients with peripheral arterial disease, suggesting an underlying prothrombotic state. Platelets from patients with critical limb ischemia are less responsive to in vitro stimulation.
authors.affiliation: Department of Vascular Surgery, Aberdeen, Scotland, United Kingdom. k.cassar@abdn.ac.uk
authors.forename: K
authors.initials: K
authors.lastname: Cassar
authors.forename: P
authors.initials: P
authors.lastname: Bachoo
authors.forename: I
authors.initials: I
authors.lastname: Ford
authors.forename: M
authors.initials: M
authors.lastname: Greaves
authors.forename: J
authors.initials: J
authors.lastname: Brittenden
mesh_terms: D000368:Aged; D005260:Female; D005340:Fibrinogen / Q000378:metabolism; D005434:Flow Cytometry; D006801:Humans; D007383:Intermittent Claudication / Q000276:immunology / Q000503:physiopathology*; D007511:Ischemia / Q000276:immunology / Q000503:physiopathology*; D035002:Lower Extremity / Q000098:blood supply*; D008297:Male; D008875:Middle Aged; D019007:P-Selectin / Q000096:biosynthesis; D016491:Peripheral Vascular Diseases / Q000276:immunology / Q000503:physiopathology*; D015539:Platelet Activation / Q000276:immunology / Q000502:physiology*; D011446:Prospective Studies
chemical_list: D019007:P-Selectin; D005340:Fibrinogen