Endovascular Treatment of Acute Ischemic Stroke May Be Safely Performed With No Time Window Limit in Appropriately Selected Patients

BACKGROUND AND PURPOSE: The traditional time window for acute ischemic stroke intra-arterial therapy (IAT) is 6 hours (late). RESULTS: Fifty-five patients (mean National Institutes of Health Stroke Scale=19.7+/-5.7) were treated, 34 early and 21 late, with mean time-to-intervention of 3.4+/-1.6 hours and 18.6+/-16.0 hours, respectively. Thrombolysis In Myocardial Ischemia 2 or 3 recanalization was achieved in 82.8% early and 85.7% late patients (P=1.0). Intracerebral hemorrhage occurred in 25.5% overall, but symptomatic intracerebral hemorrhage occurred in 8.8% of the early and 9.5% of the late patients (P=1.0). Thirty-day mortality was similar (29.4% versus 23.8%, P=0.650). At 3 months, 41.2% and 42.9%, respectively, achieved a modified Rankin Scale <or=2 (P=0.902). Only presenting National Institutes of Health Stroke Scale was a predictor of modified Rankin Scale <or=2 (OR 0.79495% CI 0.68 to 0.92, P=0.009) and death (adjusted OR 1.2995% CI 1.04 to 1.59, P=0.019). CONCLUSIONS: In appropriately selected patients, IAT for acute ischemic stroke can be performed safely regardless of stroke duration. The concept of an acute ischemic stroke treatment window for IAT should be re-evaluated with a clinical trial selecting patients with perfusion mismatch.