Background: Early recanalization is crucial to improving outcomes in patients with acute ischemic stroke (AIS). Despite successful recanalization from mechanical thrombectomy (MT), about 2-20% patients may experience reocclusion. The present study analyzes the impact of timing of antithrombotic initiation in predicting reocclusion among patients who underwent MT with successful recanalization. Methods: This is a multicenter analysis of patients who underwent successful recanalization from MT at five participating institutions across North America between January 2018- December 2024. Successful recanalization was defined as Thrombolysis in Cerebral Infarction (TICI) 2b or higher. Timing of anti-thrombotic medication (antiplatelets/ anticoagulants) initiation after MT was categorized into four groups as not started, within 24 hours, 1-7 days or beyond 7 days. Results: A total of 48 patients who developed reocclusion and 627 who did not experience reocclusion after achieving successful recanalization from MT were included. After adjusting for baseline demographics and procedural characteristics, patients who received antithrombotics within 24 hours of MT experienced a 0.18-fold lower odds of reocclusion compared to those who were not started on antithrombotics (95% CI: 0.08- 0.41, P<0.001), while patients who received antithrombotics between 1-7 days had 0.04-fold lower odds for reocclusion (95% CI: 0.04- 0.13, P<0.001) compared to those who were not started on antithrombotic therapy. Initiating antithrombotics more than 7 days after MT was not associated with a lower risk of reocclusion compared to no antithrombotic therapy. Conclusion: Early initiation of antithrombotic therapy after mechanical thrombectomy could offer protection against reocclusion, with the greatest benefit seen when started within 1-7 days, followed by within 24 hours. Initiation beyond 7 days was not protective against developing reocclusion.
Roy et al. (2026) studied this question.