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Measurement of antiplatelet inhibition during neurointerventional procedures: the effect of antithrombotic duration
D J Pandya1, B F M Fitzsimmons, T J Wolfe
1Department of Neurology, Medical College of Wisconsin and Froedtert Hospital, Milwaukee, WI 53226, USA.
Insights
Clopidogrel often fails to achieve adequate platelet inhibition in neurointerventional patients, unlike aspirin. Same-day loading doses may be insufficient, highlighting the need for careful antiplatelet regimen selection to prevent thromboembolic events.
Area of Science:
- Neurointerventional procedures
- Cardiovascular pharmacology
- Thrombosis and hemostasis
Background:
- Symptomatic thromboembolic events are common complications of neurointerventional procedures like aneurysm coiling and stenting.
- Optimal antiplatelet therapy is crucial for preventing these adverse events.
Purpose of the Study:
- To evaluate the impact of aspirin (ASA) and clopidogrel dosage and duration on platelet inhibition.
- To assess platelet inhibition using a point-of-care assay within the neurointerventional suite.
Main Methods:
- Prospective data collection on clopidogrel and aspirin therapy doses and durations.
- Utilized a point-of-care platelet function assay to measure platelet inhibition.
- Defined inadequate inhibition for ASA as >=550 ASA reaction units (ARU) and for clopidogrel as <=50% P2Y12/ADP receptor inhibition.
Main Results:
- 13% of patients on aspirin and 66% on clopidogrel exhibited inadequate platelet inhibition (P < .0001).
- Clopidogrel regimens showed varying mean P2Y12/ADP inhibition: 45% for 75 mg daily for >=7 days, 35% for 300 mg for 24 hours, and 16% for a 600 mg same-day load.
- Aspirin therapy demonstrated higher rates of adequate platelet inhibition compared to clopidogrel.
Conclusions:
- Clopidogrel frequently fails to achieve adequate platelet inhibition in neurointerventional patients, unlike aspirin.
- Same-day antiplatelet loading with clopidogrel may be insufficient for effective platelet inhibition.
- Avoidance of same-day loading, if clinically feasible, is recommended to ensure adequate platelet inhibition and reduce complication risks.
Background/Objective:
Symptomatic thromboembolic events are the most common complications associated with aneurysm coiling, and carotid and intracranial stenting. Our objective is to assess the effect of aspirin (ASA) and clopidogrel dose and duration on platelet inhibition using a point of care assay in neurointerventional (NI) suite.
Method:
The dose, duration, and point of care platelet function assay data for clopidogrel and aspirin therapy were prospectively collected between February 2006 and November 2007. Inadequate platelet inhibition for ASA was defined as >or=550 ASA reaction units (ARU), and for clopidogrel was defined as
Results:
We collected data from 216 consecutive patients. Inadequate platelet inhibition was noted in 13% of patients on aspirin and 66% of patients on clopidogrel (P-value < .0001). Patients taking clopidogrel 75 mg for >or=7 days, 300 mg for 24 hours, and 600 mg same day load had a mean P2Y12/ADP inhibition of 45%, 35% (P-value = .09), and 16%, respectively (P-value = .005).
Conclusion:
Premedication with clopidogrel, in contrast to aspirin, does not achieve adequate platelet inhibition in about two-third of the patients. Same day antiplatelet loading may be insufficient to achieve adequate platelet inhibition and should be avoided if clinically feasible.
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