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Microfluidics in Assessing Platelet Function
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Microfluidics in Assessing Platelet Function

Published on: November 8, 2024

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Low on-clopidogrel ADP- and TRAP-6-induced platelet aggregation in patients with atrial fibrillation undergoing

Diona Gjermeni1, Viktoria Anfang1, Hannah Vetter1

  • 1Department of Cardiology and Angiology, University Heart Center Freiburg - Bad Krozingen, Faculty of Medicine, University of Freiburg, Freiburg, Germany.

Journal of Thrombosis and Thrombolysis
|February 12, 2024
PubMed

Insights

High on-clopidogrel platelet reactivity (HPR) is rare in atrial fibrillation (AF) patients undergoing PCI. Low platelet reactivity was common, and ADP-induced aggregation may help identify bleeding risk in this population.

Area of Science:

  • Cardiology
  • Pharmacology
  • Thrombosis

Background:

  • High on-clopidogrel platelet reactivity (HPR) is linked to ischemic events post-percutaneous coronary intervention (PCI).
  • Atrial fibrillation (AF) patients undergoing PCI often require oral anticoagulation (OAC), complicating antiplatelet therapy management.
  • Assessing platelet reactivity in AF patients on OAC post-PCI is crucial for managing ischemic and bleeding risks.

Purpose of the Study:

  • To investigate the association between HPR, assessed by multiple electrode aggregometry (MEA), and ischemic, thromboembolic, and bleeding risks in AF patients post-PCI.
  • To determine the prevalence of HPR and low platelet reactivity (LPR) in this specific patient cohort.
  • To evaluate the utility of ADP-induced aggregation in predicting clinical outcomes.

Main Methods:

  • Prospective cohort study including 159 AF patients 1-3 days after PCI.
  • Platelet aggregation analyzed using MEA, defining HPR as ADP-induced aggregation ≥ 46 U and LPR as ≤ 18 U.
  • Primary outcome: composite of all-cause death, myocardial infarction, or stroke at 6 months. Secondary outcome: bleeding events.

Main Results:

  • The majority of patients (93%) exhibited low overall platelet aggregability, with only 1% showing HPR and 79% demonstrating LPR.
  • ADP-induced aggregation did not significantly correlate with the primary ischemic outcome (p=0.309).
  • ADP-induced aggregation showed an inverse correlation with bleeding risk (r=-0.201, p=0.011), suggesting a potential role in bleeding risk assessment.

Conclusions:

  • HPR is uncommon in AF patients undergoing PCI, and overall platelet aggregability is typically low.
  • Current conventional cut-off values for HPR may not be appropriate for AF patients on OAC post-PCI.
  • ADP-induced aggregation levels may serve as a valuable tool for identifying patients at higher risk of bleeding.

Keywords:
Atrial fibrillationDirect oral anticoagulantsDual anti-platelet therapyPercutaneous coronary interventionPlatelet aggregation

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