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.
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.
Saw
Jacqueline
J
Division of Cardiology, Vancouver General Hospital, University of British Columbia, Vancouver, British Columbia, Canada. jsaw@interchange.ubc.ca
Densem
Cameron
C
Walsh
Simon
S
Jokhi
Percy
P
Starovoytov
Andrew
A
Fox
Rebecca
R
Wong
Graham
G
Buller
Christopher
C
Ricci
Donald
D
Mancini
G B John
GB
Fung
Anthony
A
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
D010455:Peptides; D010975:Platelet Aggregation Inhibitors; D019039:Platelet Glycoprotein GPIIb-IIIa Complex; D000077144:Clopidogrel; D000077542:Eptifibatide; D013988:Ticlopidine; D001241:Aspirin