title: Withdrawal of anti-epileptic medications during video EEG monitoring does not alter ECG parameters or HRV.
abstract: OBJECTIVE
  To assess if anti-epileptic drug (AED) withdrawal/cessation results in changes in ECG parameters and/or measures of heart rate variability (HRV), in patients having VEEG monitoring, that might affect susceptibility to sudden death in epilepsy.
  
  
  METHODS
  In this study, we included 36 patients with medically refractory epilepsy undergoing continuous video-EEG-ECG monitoring in hospital for pre-surgical assessment. We recorded and analysed multiple 10-min epochs of 2-lead ECG during periods when the subjects were awake and in REM and non-REM sleep, both on admission, and after the subjects had been partially or completely weaned from their AEDs. We compared ECG parameters and measures of HRV from these recorded epochs before and after AED reduction/cessation, with each patient acting as their own comparator. Epochs measured during awake, REM, and non-REM periods were analysed separately. In addition, we analysed a subgroup of patients who had been withdrawn from Na+-channel blocking medications specifically, to analyse the effect of this particular class of AEDs in isolation.
  
  
  RESULTS
  Upon AED withdrawal, we observed a small increase in heart rate and shortening of the QT interval, when subjects were awake, but no other changes in ECG parameters were detected, nor did we find changes in any measure of HRV. In addition, no significant changes were found during sleep. Similar results were found in the analysis of the subgroup of patients withdrawn from Na+-channel blocking AEDs.
  
  
  CONCLUSIONS
  Our study does not support a prominent role for AEDs, and withdrawal/cessation of AEDs, in deranging cardiac physiology during video EEG monitoring in medically refractory epilepsy patients undergoing video EEG monitoring.
authors.affiliation: School of Medical Sciences, Sydney Medical School, University of Sydney, Sydney, Australia. mste9532@uni.sydney.edu.au
authors.forename: Maurizio
authors.initials: M
authors.lastname: Stefani
authors.forename: Hisatomi
authors.initials: H
authors.lastname: Arima
authors.forename: Armin
authors.initials: A
authors.lastname: Mohamed
mesh_terms: D000328:Adult; D000368:Aged; D000927:Anticonvulsants / Q000009:adverse effects* / Q000627:therapeutic use; D004351:Drug Resistance; D004359:Drug Therapy, Combination; D004562:Electrocardiography / Q000187:drug effects*; D004569:Electroencephalography / Q000187:drug effects*; D004827:Epilepsy / Q000188:drug therapy / Q000503:physiopathology; D005260:Female; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D014741:Video Recording; D028761:Withholding Treatment; D055815:Young Adult
chemical_list: D000927:Anticonvulsants
keywords: AED; Arrhythmia; Electrocardiogram; Epilepsy; Polypharmacy; SUDEP