Aspirin resistance is associated with a high incidence of myonecrosis after non-urgent percutaneous coronary intervention despite clopidogrel pretreatment

J Am Coll Cardiol. 2004 Mar 17;43(6):1122-6. doi: 10.1016/j.jacc.2003.12.034.


Objectives: We sought to investigate the effect of aspirin resistance on the incidence of myonecrosis after non-urgent percutaneous coronary intervention (PCI) among patients pretreated with clopidogrel.

Background: Oral antiplatelet therapy using aspirin and a thienopyridine is the standard of care for preventing thrombotic complications of PCI. The effect of aspirin resistance on the outcomes of patients undergoing PCI is unknown.

Methods: We used the Ultegra Rapid Platelet Function Assay-ASA (Accumetrics Inc., San Diego, California) to determine aspirin responsiveness of 151 patients scheduled for non-urgent PCI. All patients received a 300-mg loading dose of clopidogrel >12 h before and a 75-mg maintenance dose in the morning of the PCI. The incidence of myonecrosis was measured by creatine kinase-myocardial band (CK-MB) and by troponin I (TnI) elevations after PCI.

Results: A total of 29 (19.2%) patients were noted to be aspirin-resistant. There was a significantly higher incidence of female subjects in the aspirin-resistant versus aspirin-sensitive groups. The incidence of any CK-MB elevation was 51.7% in aspirin-resistant patients and 24.6% in aspirin-sensitive patients (p = 0.006). Elevation of TnI was observed in 65.5% of aspirin-resistant patients and 38.5% of aspirin-sensitive patients (p = 0.012). Multivariate analysis revealed aspirin resistance (odds ratio [OR] 2.9; 95% confidence interval [CI] 1.2 to 6.9; p = 0.015) and bifurcation lesion (OR 2.8; 95% CI 1.3 to 6.0; p = 0.007) to be independent predictors of CK-MB elevation after PCI.

Conclusions: Despite adequate pretreatment with clopidogrel, patients with aspirin resistance as measured by a point-of-care assay have an increased risk of myonecrosis following non-urgent PCI.

MeSH terms

  • Aged
  • Angioplasty, Balloon, Coronary*
  • Aspirin / administration & dosage*
  • Clopidogrel
  • Coronary Artery Disease / therapy*
  • Creatine Kinase / blood
  • Creatine Kinase, MB Form
  • Drug Resistance*
  • Female
  • Humans
  • Incidence
  • Isoenzymes / blood
  • Male
  • Middle Aged
  • Myocardial Infarction / blood*
  • Platelet Aggregation Inhibitors / administration & dosage*
  • Postoperative Period
  • Sex Factors
  • Ticlopidine / administration & dosage*
  • Ticlopidine / analogs & derivatives*
  • Troponin I / blood


  • Isoenzymes
  • Platelet Aggregation Inhibitors
  • Troponin I
  • Clopidogrel
  • Creatine Kinase
  • Creatine Kinase, MB Form
  • Ticlopidine
  • Aspirin