Efficacy, safety and dosing of intravenous alteplase administered beyond 4.5 hours for ischemic stroke: systematic review and meta-analysis

Intravenous alteplase administered beyond 4.5 h after stroke onset is associated with improved functional outcomes in selected patients, despite an increased risk of symptomatic intracranial hemorrhage and no significant effect on mortality. These findings support the use of extended-window thrombolysis when guided by appropriate clinical or imaging-based selection criteria.