Is Clopidogrel Premedication Useful to Reduce Thromboembolic Events During Coil Embolization for Unruptured Intracranial Aneurysms?

BACKGROUND: Thromboembolism is a common complication related to coil embolization of intracranial aneurysms. OBJECTIVE: To identify factors related to thromboembolic events during coil embolization for unruptured intracranial aneurysms and to evaluate the role of clopidogrel premedication to prevent thromboembolisms. METHODS: Since March 2006, clopidogrel has been administered to patients with unruptured aneurysms before coil embolization (the clopidogrel group) in our institution. The clopidogrel group (416 patients with 485 aneurysms) and the historical control group (140 patients with 159 aneurysms who received no antiplatelet premedication) were compared to find the efficacy of clopidogrel premedication. Various factors, including age, sex, body weight, and medical history of hypertension, diabetes mellitus, hyperlipidemia, smoking, previous stroke, and heart disease, as well as clopidogrel premedication, were analyzed in relationship to the development of a procedure-related thromboembolism. RESULTS: Procedure-related thromboembolic events tended to occur less frequently in the clopidogrel group compared with the control group (7.4% vs 12.6%; P = .05), and clopidogrel premedication could modify the risk in female patients from 11.1% to 5.2% (P = .04). The use of multiple logistic regression analysis identified clopidogrel premedication (P = .03), smoking (P = .002), and hyperlipidemia (P = .02) as significant factors related to the formation of thromboembolism. CONCLUSION: Clopidogrel premedication seems to have a beneficial effect in reducing the number of procedure-related thromboembolisms during coil embolization for unruptured intracranial aneurysms, especially in female patients. Smoking and hyperlipidemia were independent risk factors related to thromboembolism.