Clinically distinct electroencephalographic phenotypes of early myoclonus after cardiac arrest

作者：Jonathan Elmer, Jon C. Rittenberger, John Faro, Bradley J. Molyneaux, Alexandra Popescu, Clifton W. Callaway, Maria Baldwin, for the Pittsburgh Post‐Cardiac Arrest Service · 发表于：Annals of Neurology · 年份：2016 · DOI：10.1002/ana.24697 · 被引用次数：202 · 研究领域：Cardiac Arrest and Resuscitation、Glycogen Storage Diseases and Myoclonus、Neurological disorders and treatments

OBJECTIVE: We tested the hypothesis that there are readily classifiable electroencephalographic (EEG) phenotypes of early postanoxic multifocal myoclonus (PAMM) that develop after cardiac arrest. METHODS: We studied a cohort of consecutive comatose patients treated after cardiac arrest from January 2012 to February 2015. For patients with clinically evident myoclonus before awakening, 2 expert physicians reviewed and classified all EEG recordings. Major categories included: Pattern 1, suppression-burst background with high-amplitude polyspikes in lockstep with myoclonic jerks; and Pattern 2, continuous background with narrow, vertex spike-wave discharges in lockstep with myoclonic jerks. Other patterns were subcortical myoclonus and unclassifiable. We compared population characteristics and outcomes across these EEG subtypes. RESULTS: Overall, 401 patients were included, of whom 69 (16%) had early myoclonus. Among these patients, Pattern 1 was the most common, occurring in 48 patients (74%), whereas Pattern 2 occurred in 8 patients (12%). The remaining patients had subcortical myoclonus (n = 2, 3%) or other patterns (n = 7, 11%). No patients with Pattern 1, subcortical myoclonus, or other patterns survived with favorable outcome. By contrast, 4 of 8 patients (50%) with Pattern 2 on EEG survived, and 4 of 4 (100%) survivors had favorable outcomes despite remaining comatose for 1 to 2 weeks postarrest. INTERPRETATION: Early PAMM is common after cardiac arrest. We describe 2 dis...