title: Uniform platelet activation exists before coronary stent implantation despite aspirin therapy.
abstract: BACKGROUND
  Platelets play an important role in the natural history of coronary artery disease. Enhanced platelet aggregation and receptor expression unquestionably occur after coronary stent implantation; however, the functional characteristics of platelets before stenting have not been fully elucidated.
  
  
  METHODS
  Platelets were assessed before intervention by platelet-rich plasma aggregation (PA) with 5 mmol adenosine diphosphate (ADP) and 1 mg/mL collagen; whole blood aggregation (WBA) by 1 mg/mL collagen; shear-induced closure time (CT); contractile force (CF); and expression of 9 surface receptors by flow cytometry in 126 patients undergoing elective coronary artery stent placement. All patients received aspirin for at least 7 days. The data were compared with those from 64 healthy volunteers.
  
  
  RESULTS
  Each test revealed sustained platelet activation in patients undergoing coronary stenting compared with control values. These differences were significant for collagen-induced PA (P =.031); CF (P =.0001); expression of glycoprotein (GP) IIb/IIIa (P =.0001); P-selectin (P =.0008); platelet/endothelial cell adhesion molecule (PECAM)-1 (P =.0001); CD107a (P =.0001); CD107b (P =.0004); and CD63 (P =.009).
  
  
  CONCLUSIONS
  Platelets are indeed activated before coronary stenting despite antecedent therapy with aspirin.
authors.affiliation: Center for Thrombosis Research, Sinai Hospital, Baltimore, MD 21215, USA. Heartdrug@aol.com
authors.forename: V L
authors.initials: VL
authors.lastname: Serebruany
authors.forename: C C
authors.initials: CC
authors.lastname: Cummings
authors.forename: A I
authors.initials: AI
authors.lastname: Malinin
authors.forename: S R
authors.initials: SR
authors.lastname: Steinhubl
authors.forename: P A
authors.initials: PA
authors.lastname: Gurbel
mesh_terms: D000328:Adult; D001241:Aspirin / Q000494:pharmacology / Q000627:therapeutic use*; D003327:Coronary Disease / Q000097:blood* / Q000188:drug therapy / Q000601:surgery*; D003331:Coronary Vessels / Q000601:surgery; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015539:Platelet Activation / Q000187:drug effects*; D010974:Platelet Aggregation / Q000187:drug effects; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology / Q000627:therapeutic use*; D011300:Preoperative Care; D015607:Stents
chemical_list: D010975:Platelet Aggregation Inhibitors; D001241:Aspirin