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Interventional Diagnostic Procedure: A Practical Guide for the Assessment of Coronary Vascular Function
10:28

Interventional Diagnostic Procedure: A Practical Guide for the Assessment of Coronary Vascular Function

Published on: March 15, 2022

Inter-individual variability in response to clopidogrel in patients with coronary artery disease

Artur Dziewierz1, Dariusz Dudek, Grzegorz Heba

  • 12nd Department of Cardiology, Institute of Cardiology, Jagiellonian University College of Medicine, Cracow, Poland.

Kardiologia Polska
|April 9, 2005
PubMed

Insights

Clopidogrel resistance can be identified early, within six hours of treatment initiation, using platelet function tests. This rapid assessment helps identify non-responders to clopidogrel, improving patient management.

Area of Science:

  • Pharmacology
  • Cardiovascular Medicine
  • Clinical Chemistry

Background:

  • Clopidogrel, often combined with aspirin, is vital for reducing ischemic events in coronary artery disease (CAD).
  • Limited data exist on inter-individual variability in clopidogrel response.

Purpose of the Study:

  • To determine the incidence of clopidogrel resistance.
  • To evaluate early identification of non-responders using platelet function assessment.

Main Methods:

  • Assessed platelet aggregation inhibition (DPAI) in 31 stable angina patients treated with aspirin.
  • Measured DPAI at baseline and 3, 6, 12, and 24 hours post-clopidogrel loading dose (300 mg).

Main Results:

  • 22.6% of patients were non-responders (DPAI ≤10%) at 24 hours.
  • Early non-responders at 6 hours (87.5%) remained resistant at 24 hours.
  • No significant differences in ischemic or bleeding complications were observed between groups.

Conclusions:

  • Platelet aggregation inhibition assessment enables early identification of clopidogrel resistance within six hours.
  • Rapid whole blood platelet function assessment is clinically feasible for routine practice.
Abstract

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