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Pathophysiologic mechanisms, neuroimaging and treatment in wake-up stroke

Published online by Cambridge University Press:  12 September 2019

Mohamed Elfil*
Department of Neurology, Yale University, New Haven, Connecticut, USA
Mohamed Eldokmak
Department of Neurology, Yale University, New Haven, Connecticut, USA
Alireza Baratloo
Prehospital and Hospital Emergency Research Center, Tehran University of Medical Sciences, Tehran, Iran Department of Emergency Medicine, Sina Hospital, Tehran University of Medical Sciences, Tehran, Iran
Nada Ahmed
Department of Neurology, Yale University, New Haven, Connecticut, USA
Hardik P. Amin
Department of Neurology, Yale University, New Haven, Connecticut, USA
Brian B. Koo
Department of Neurology, Yale University, New Haven, Connecticut, USA Department of Neurology, Connecticut Veterans Affairs Healthcare Systems, Newington, Connecticut, USA


Wake-up stroke (WUS) or ischemic stroke occurring during sleep accounts for 14%–29.6% of all ischemic strokes. Management of WUS is complicated by its narrow therapeutic time window and attributable risk factors, which can affect the safety and efficacy of administering intravenous (IV) tissue plasminogen activator (t-PA). This manuscript will review risk factors of WUS, with a focus on obstructive sleep apnea, potential mechanisms of WUS, and evaluate studies assessing safety and efficacy of IV t-PA treatment in WUS patients guided by neuroimaging to estimate time of symptom onset. The authors used PubMed (1966 to March 2018) to search for the term “Wake-Up Stroke” cross-referenced with “pathophysiology,” ‘‘pathogenesis,” “pathology,” “magnetic resonance imaging,” “obstructive sleep apnea,” or “treatment.” English language Papers were reviewed. Also reviewed were pertinent papers from the reference list of the above-matched manuscripts. Studies that focused only on acute Strokes with known-onset of symptoms were not reviewed. Literature showed several potential risk factors associated with increased risk of WUS. Although the onset of WUS is unknown, a few studies investigated the potential benefit of magnetic resonance imaging (MRI) in estimating the age of onset which encouraged conducting clinical trials assessing the efficacy of MRI-guided thrombolytic therapy in WUS.

© Cambridge University Press 2019

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