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Updated: Aug 8, 2026
Turbidimetry on Human Washed Platelets: The Effect of the Pannexin1-inhibitor Brilliant Blue FCF on Collagen-induced Aggregation
Published on: April 6, 2017
Overestimation of platelet aspirin resistance detection by thrombelastograph platelet mapping and validation by
Udaya S Tantry1, Kevin P Bliden, Paul A Gurbel
1Sinai Center for Thrombosis Research, Baltimore, Maryland 21215, USA.
Objectives:
This study sought to determine the prevalence of platelet aspirin resistance using methods that directly indicate the degree of platelet cyclooxygenase inhibition.
Background:
Aspirin resistance in platelets may be overestimated by nonspecific laboratory measurements that do not isolate cyclooxygenase activity.
Methods:
Arachidonic acid (AA)-induced light-transmittance platelet aggregation (LTA) and thrombelastography (TEG) platelet mapping were performed on the blood of healthy subjects (n = 6) before and 24 h after receiving 325 mg aspirin, and on 223 patients reporting compliance with long-term daily aspirin treatment (n = 203 undergoing percutaneous intervention [PCI] and n = 20 with a history of stent thrombosis). Aspirin resistance was defined as >20% aggregation by LTA or >50% aggregation by TEG.
Results:
In healthy subjects, AA-induced aggregation by LTA was 82 +/- 10% before and 2 +/- 1% at 24 h after aspirin (p < 0.001), and aggregation by TEG was 86 +/- 14% before and 5 +/- 7% at 24 h after aspirin (p < 0.001). In compliant patients, AA-induced aggregation by LTA was 3 +/- 2% before PCI and 3 +/- 2% after PCI (p = NS), and aggregation by TEG was 5 +/- 9% before PCI and 6 +/- 14% after PCI (p = NS). Seven PCI patients were noncompliant, and all were aspirin sensitive after in-hospital aspirin treatment. Among 223 patients, only one patient ( approximately 0.4%) was resistant to aspirin treatment.
Conclusions:
Platelet aspirin resistance assessed by methods that directly indicate inhibition of cyclooxygenase is rare in compliant patients with coronary artery disease.
