Non-convulsive status epilepticus after ischemic stroke: a hospital-based stroke cohort study

Abstract

To evaluate in the setting of a stroke unit ward the usefulness of a prolonged (>6 h) video-EEG recording (PVEEG) in identifying non-convulsive status epilepticus (NCSE) in patients with an acute ischemic stroke. Predictors of NCSE were also evaluated. Patients with an acute ischemic stroke, referred to our unit, were included in this prospective observational study. A PVEEG recording was implemented after stroke in all patients during the first week: (a) promptly in those exhibiting a clear or suspected epileptic manifestation; (b) at any time during the routine activity in the remaining patients. After the first week, a standard EEG/PVEEG recording was hooked up only in presence of an evident or suspected epileptic manifestation or as control of a previous epileptic episode. NCSE was identified in 32 of the 889 patients (3.6 %) included in the study. It occurred early (within the first week) in 20/32 (62.5 %) patients and late in the remaining 12. Diagnosis was made on the basis of a specific clinical suspect (n = 19, 59.4 %) or without any suspect (n = 13, 40.6 %). In a multivariate analysis, a significant association of NCSE was observed with NIHSS score, infarct size and large atherothrombotic etiology. NCSE is not a rare event after an acute ischemic stroke and a delayed diagnosis could worsen patient prognosis. Since NCSE can be difficult to be diagnosed only on clinical grounds, implementation of a prompt PVEEG should be kept available in a stroke unit whenever a patient develop signs, although subtle, consistent with NCSE.