CT-based intravenous thrombolysis 3-4.5 hours after acute ischemic stroke in clinical practice

Background: Outcome of stroke patients selected with cerebral computed tomography for intravenous thrombolysis administered in clinical routine from 3 to 4.5 hours after symptoms onset is not well investigated. Aim of this single-center, prospective, observational study was to compare the safety and efficacy of intravenous alteplase given in routine clinical praxis 181-270 minutes (late) and within 180 minutes (early) after stroke onset in patients selected with cerebral computed tomography. Methods: A total of 454 consecutive patients underwent intravenous thrombolysis within 4.5 hours after stroke onset. Sixty of 454 patients were excluded (inclusion in a controlled-randomized trial, n=51; stroke mimics, n=9). Of remaining 394 patients, 100 were included in the late group, and 294 were included in the early group. The outcome parameters of symptomatic intracranial hemorrhage at 24 hours, and mortality and favorable outcome (modified Rankin scale score 0-1) at 3 months, and its predictors were investigated. Results: In the late cohort, median baseline National Institutes of Health Stroke Scale score was lower (9.5, interquartile range (IQR): 5-13; 11.3, IQR: 6-16; P=0.01), and median time-to-treatment was longer (209, IQR: 190-222 minutes; 142, IQR: 125-170 minutes; P<0.0001) than in the early group. The incidence of symptomatic intracranial hemorrhage (2.0% versus 2.4%; P=1.0), death (9.0% versus 9.9%; P=1.0) and favorable outcome (58.0% versus 51.5%; P=0.3) did not differ between the late and early cohorts. Conclusion: These data suggest that intravenous alteplase administered 181-270 minutes after symptoms onset in stroke patients selected with cerebral computed tomography is also beneficial in real-life clinical practice.