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A Method to Study the C924T Polymorphism of the Thromboxane A2 Receptor Gene
07:00

A Method to Study the C924T Polymorphism of the Thromboxane A2 Receptor Gene

Published on: April 1, 2019

[Stent thrombosis and clopidogrel response variability: is the genetic test useful in clinical practice?]

Maria Francesca Notarangelo1, Nicola Marziliano, Rossella Giacalone

  • 1Dipartimento Cardio-Nefro-Polmonare, Azienda Ospedaliero-Universitaria di Parma, Italy. francescanotarangelo@yahoo.it

Giornale Italiano Di Cardiologia (2006)
|September 28, 2011
PubMed

Insights

Clopidogrel is an effective antiplatelet drug, but genetic variations affect patient response. Genotyping may guide therapy to reduce risks of thrombotic events and bleeding.

Area of Science:

  • Cardiovascular Medicine
  • Pharmacogenomics

Background:

  • Clopidogrel is a key antiplatelet agent for preventing thrombotic events in acute coronary syndrome and after coronary stent placement.
  • A significant portion of patients exhibit high platelet reactivity despite clopidogrel treatment, leading to adverse outcomes.

Observation:

  • About 30% of patients show high platelet reactivity, increasing risks of atherothrombotic complications.
  • Poor drug response contributes to recurrent ischemic events (up to 13%) and stent thrombosis (1-3%).
  • Enhanced drug response is linked to major bleeding events (approx. 1.5%).

Findings:

  • Genetic variations are increasingly recognized as determinants of individual responses to clopidogrel.
  • This has spurred interest in genotyping patients to identify those at higher risk with clopidogrel therapy.

Implications:

  • Further clinical data are needed to confirm if genotype-guided therapy reduces ischemic and bleeding events.
  • Successful validation could justify routine genetic testing for personalized antiplatelet therapy in cardiovascular medicine.

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