title: The effects of aspirin and clopidogrel response on myonecrosis after percutaneous coronary intervention: a BRIEF-PCI (Brief Infusion of Intravenous Eptifibatide Following Successful Percutaneous Coronary Intervention) trial substudy.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the effects of aspirin and clopidogrel response on myonecrosis after percutaneous coronary intervention (PCI) with glycoprotein (GP) IIb/IIIa blockade.
  
  
  BACKGROUND
  Aspirin and clopidogrel resistance is increasingly recognized, but its effects on PCI outcomes with GP IIb/IIIa blockade are unknown.
  
  
  METHODS
  This was a prospective, pre-specified substudy of the BRIEF-PCI (Brief Infusion of Intravenous Eptifibatide Following Successful Percutaneous Coronary Intervention) trial, which randomized 624 patients to 18-h or <2-h eptifibatide infusion after uncomplicated PCI. To be eligible, patients must have been pre-treated with aspirin (>or=5 days) and clopidogrel (75 mg/day >or=5 days, 300 mg loading >or=6 h, or 600 mg loading >or=2 h) and must not have received GP IIb/IIIa inhibitors within 48 h. Verify-Now Aspirin and Clopidogrel (P2Y(12)) assays were performed at baseline before PCI. Patients with aspirin reaction unit (ARU) >or=550 were labeled as aspirin resistant. Clopidogrel low-responders were defined as those in the lowest quartile of platelet inhibition. The primary end point was the prevalence of myonecrosis within 24 h after PCI.
  
  
  RESULTS
  We enrolled 209 patients into our substudy, of which 185 had aspirin response assessed, 198 had clopidogrel response assessed, and 174 had both assessed. There were 4.9% who were aspirin resistant. Clopidogrel low-responders were defined as those in the lowest quartile with platelet inhibition <19%. Only 1.1% had both aspirin resistance and low clopidogrel response. There was no difference in myonecrosis prevalence among aspirin-resistant compared with aspirin-sensitive patients (11.1% vs. 27.8%, p = 0.259) or among clopidogrel low-responders compared with clopidogrel responders (23.5% vs. 29.3%, p = 0.433).
  
  
  CONCLUSIONS
  Aspirin and clopidogrel response did not affect myonecrosis prevalence amongst patients who received eptifibatide for PCI.
authors.affiliation: Division of Cardiology, Vancouver General Hospital, University of British Columbia, Vancouver, British Columbia, Canada. jsaw@interchange.ubc.ca
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Saw
authors.forename: Cameron
authors.initials: C
authors.lastname: Densem
authors.forename: Simon
authors.initials: S
authors.lastname: Walsh
authors.forename: Percy
authors.initials: P
authors.lastname: Jokhi
authors.forename: Andrew
authors.initials: A
authors.lastname: Starovoytov
authors.forename: Rebecca
authors.initials: R
authors.lastname: Fox
authors.forename: Graham
authors.initials: G
authors.lastname: Wong
authors.forename: Christopher
authors.initials: C
authors.lastname: Buller
authors.forename: Donald
authors.initials: D
authors.lastname: Ricci
authors.forename: G B John
authors.initials: GB
authors.lastname: Mancini
authors.forename: Anthony
authors.initials: A
authors.lastname: Fung
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects / Q000401:mortality; D001241:Aspirin / Q000008:administration & dosage*; D001792:Blood Platelets / Q000187:drug effects* / Q000378:metabolism; D000077144:Clopidogrel; D003324:Coronary Artery Disease / Q000097:blood / Q000401:mortality / Q000628:therapy*; D004334:Drug Administration Schedule; D004351:Drug Resistance; D004359:Drug Therapy, Combination; D000077542:Eptifibatide; D005260:Female; D006331:Heart Diseases / Q000097:blood / Q000209:etiology / Q000473:pathology / Q000517:prevention & control*; D006470:Hemorrhage / Q000139:chemically induced; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood / Q000209:etiology / Q000401:mortality / Q000517:prevention & control; D009336:Necrosis; D010455:Peptides / Q000008:administration & dosage* / Q000009:adverse effects; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage* / Q000009:adverse effects; D019039:Platelet Glycoprotein GPIIb-IIIa Complex / Q000037:antagonists & inhibitors* / Q000378:metabolism; D011446:Prospective Studies; D013988:Ticlopidine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D010455:Peptides; D010975:Platelet Aggregation Inhibitors; D019039:Platelet Glycoprotein GPIIb-IIIa Complex; D000077144:Clopidogrel; D000077542:Eptifibatide; D013988:Ticlopidine; D001241:Aspirin