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Prevalence and risk factors for aspirin and clopidogrel resistance in cerebrovascular stenting

S Prabhakaran1, K R Wells, V H Lee

  • 1Rush University Medical Center, Department of Neurological Sciences, Chicago, IL 60612, USA. Shyam_Prabhakaran@rush.edu

AJNR. American Journal of Neuroradiology
|November 9, 2007
PubMed

Insights

Antiplatelet drug resistance is a concern in patients receiving cerebrovascular stents. While aspirin resistance was uncommon, over half of patients showed clopidogrel resistance, indicating a need for further research into optimal antiplatelet therapy.

Area of Science:

  • Cardiovascular Medicine
  • Neurology
  • Pharmacology

Background:

  • Prevalence of antiplatelet drug resistance after cerebrovascular stent placement is largely unknown.
  • Assessing antiplatelet drug effects is crucial for patient management post-stenting.

Purpose of the Study:

  • To evaluate the feasibility of monitoring antiplatelet drug effects in patients undergoing cerebrovascular stent placement.
  • To determine the prevalence of aspirin and clopidogrel resistance in this patient cohort.

Main Methods:

  • Prospective collection of clinical, laboratory, and radiographic data.
  • Utilized rapid platelet function assay-aspirin (RPFA-ASA) for aspirin reaction units (ARU).
  • Employed P2Y12 assay to measure P2Y12 reaction units and platelet inhibition percentage.

Main Results:

  • Aspirin resistance (ARU > 550) was observed in 4.2% of patients (3/71).
  • Clopidogrel resistance (<40% platelet inhibition) was found in 51.9% of patients (28/55).
  • Older age (>55 years) and diabetes were associated with reduced platelet inhibition from clopidogrel.

Conclusions:

  • Aspirin resistance is infrequent, but clopidogrel resistance is common in patients undergoing cerebrovascular stenting.
  • Point-of-care testing can monitor antiplatelet drug effects.
  • Further investigation into optimal antiplatelet dosing, timing, and duration is warranted.
Abstract

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