Clinical Effect of Thrombolysis in Wake-Up Stroke Compared to Non-Wake-Up Stroke

Abstract

Background and Aims: In known onset stroke (KOS) cerebral CT is performed to select patients eligible for intravenous thrombolysis (IVT) while MRI (DWI-FLAIR) mismatch aids selection of patients in wake-up stroke (WUPS). In this study, the clinical outcome and safety profile of IVT in WUPS patients is compared to KOS patients.

Methods: IVT treated WUPS patients in the NOR-TEST trial and immediately hereafter and KOS patients also treated at Stavanger University Hospital were included. Retrospective review showed that the traditional MRI mismatch concept in clinical praxis was extended at our center to also treat WUPS patients with partial mismatch and even match. CT excluded intracerebral hemorrhage (ICH) in KOS patients. Clinical improvement was rated by NIHSS and modified Rankin Scale (mRS) at 3 months, while safety analyzed by ICH.

Results: Total 83 WUPS patients and 166 KOS patients were treated with IVT. Patients with pre-stroke mRS < 2 were included in the clinical analysis, giving 73 WUPS patients (44 mismatch, 15 partial mismatch and 14 match) and 158 KOS patients. Comparing each WUPS subgroup with the KOS group, only the partial mismatch group showed significant higher NIHSS at admission; (p=0.007). Comparing to the KOS group, only the mismatch group showed non- inferior NIHSS at discharge; (p=0.385) while all WUPS subgroups were non-inferior with (ΔNIHSS-24h) and (ΔNIHSS-disc). Comparable mRS at 3 months in all groups without any event of ICH.

Conclusion: Compared to the KOS patients, the partial mismatch patients demonstrated comparable and non-inferior neurological improvement and safety profile.