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Microfluidics in Assessing Platelet Function
06:47

Microfluidics in Assessing Platelet Function

Published on: November 8, 2024

Consistent platelet inhibition during long-term maintenance-dose clopidogrel therapy among 359 compliant outpatients

Victor L Serebruany1, Alex I Malinin, Dan Atar

  • 1HeartDrug Research Laboratories, Johns Hopkins University, Towson, MD 21204, USA. heartdrug@aol.com

American Heart Journal
|February 20, 2007
PubMed

Insights

Long-term clopidogrel therapy in outpatients consistently reduces platelet aggregation. This maintenance dose provides a balanced approach to secondary prevention, avoiding nonresponse and excessive bleeding risks.

Area of Science:

  • Cardiovascular Medicine
  • Pharmacology
  • Hematology

Background:

  • Limited data on long-term clopidogrel response in outpatients.
  • Previous studies focused on acute settings with varying definitions.
  • Need to assess platelet characteristics with maintenance doses (>30 days).

Purpose of the Study:

  • To describe ex vivo platelet aggregation and activation.
  • To evaluate responses to long-term clopidogrel maintenance therapy (75 mg/d).
  • To analyze platelet characteristics in outpatients post-coronary stenting or ischemic stroke.

Main Methods:

  • Secondary post hoc analysis of existing data.
  • Included compliant patients with coronary stenting (n=237) or ischemic stroke (n=122).
  • Patients received clopidogrel and aspirin combination therapy.

Main Results:

  • Consistent inhibition of adenosine diphosphate-induced platelet aggregation (mean 52.9%).
  • Inhibition correlated with reduced expression of PECAM-1, glycoprotein IIb/IIIa, and PAR-1.
  • No patients exhibited hyporesponsiveness or profound inhibition.

Conclusions:

  • Long-term clopidogrel therapy yields consistent, less variable platelet inhibition compared to acute settings.
  • Absence of nonresponse and profound inhibition supports a balance between efficacy and bleeding risk.
  • Facilitates long-term secondary prevention in outpatients after vascular events.
Abstract

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