Thrombolysis for acute wake-up and unclear onset strokes with alteplase at 0.6 mg/kg in clinical practice: THAWS2 Study

Introduction: The aim of this study was to determine the safety and efficacy of intravenous (IV) alteplase at 0.6 mg/kg for patients with acute wake-up or unclear onset strokes in clinical practice.Methods: This multicenter observational study enrolled acute ischemic stroke patients with last-known-well time >4.5 h who had mismatch between DWI and FLAIR and were treated with IV alteplase. The safety outcomes were symptomatic intracranial hemorrhage (sICH) after thrombolysis, all-cause deaths and all adverse events. The efficacy outcomes were favorable outcome defined as an mRS score of 0-1 or recovery to the same mRS score as the premorbid score, complete independence defined as an mRS score of 0-1 at 90 days, and change in NIHSS at 24 h from baseline.Results: Sixty-six patients (35 females; mean age, 74 +/- 11 years; premorbid complete independence, 54 [82%]; median NIHSS on admission, 11) were enrolled at 15 hospitals. Two patients (3%) had sICH. Median NIHSS changed from 11 (IQR, 6.75-16.25) at baseline to 5 (3-12.25) at 24 h after alteplase initiation (change, -4.8 +/- 8.1). At discharge, 31 patients (47%) had favorable outcome and 29 (44%) had complete independence. None died within 90 days. Twenty-three (35%) also underwent mechanical thrombectomy (no sICH, NIHSS change of -8.5 +/- 7.3), of whom 11 (48%) were completely independent at discharge.Conclusions: In real-world clinical practice, IV alteplase for unclear onset stroke patients with DWI-FLAIR mismatch provided safe and efficacious outcomes comparable to those in previous trials. Additional mechanical thrombectomy was performed safely in them.