Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

BACKGROUND: The choice of appropriate antiplatelet therapy before the Pipeline Embolization Device (PED) placement is usually guided by platelet function testing such as light transmission aggregometry (LTA). In this study, we aimed to define the optimal threshold LTA value for clopidogrel responsiveness to predict the risk of postprocedural thromboembolic complications and to help guide appropriate antiplatelet regimen. METHODS: A prospectively maintained database at an academic neurosurgical center in the United States was retrospectively analyzed from 2014 to 2017 to identify patients with unruptured intracranial aneurysms treated with the PED. Clinical and radiographic data were analyzed to identify thromboembolic complications in the context of platelet function testing performed by LTA. RESULTS: A total of 95 procedures were performed for PED placement to treat 110 unruptured intracranial aneurysms. Thromboembolic complications were encountered in 4 (4.2%) of these patients. After stratifying the complication rate based on the maximal extent of platelet aggregation after administration of an exogenous platelet agonist, a marked increase in thromboembolic events was observed in patients with LTA values greater than 50%. When LTA was dichotomized based on this value, patients with an LTA value less than 50% had a thromboembolic complication rate of 1.3% (1/80), compared with 20% (3/15) for those with LTA values ≥50% (P = 0.001). CONCLUSIONS: We observed the greatest increase in the rate of thromboembolic complications with LTA values of ≥50%. This can serve as an appropriate cut-off value for determining the clopidogrel response in patients undergoing endovascular treatment with the PED.

Original publication




Journal article


World Neurosurg

Publication Date





e146 - e152


Aneurysm, Clopidogrel, Intracranial, LTA, Light transmission aggregometry, Pipeline flow diversion, Thromboembolic complications, Adult, Aged, Aged, 80 and over, Clopidogrel, Databases, Factual, Dose-Response Relationship, Drug, Embolization, Therapeutic, Female, Humans, Intracranial Aneurysm, Male, Middle Aged, Platelet Aggregation, Platelet Aggregation Inhibitors, Platelet Function Tests, Prospective Studies, Retrospective Studies, Risk, Stents, Thromboembolism, Thrombophilia, Ticlopidine, Treatment Outcome