title: Periictal heart rate variability analysis suggests long-term postictal autonomic disturbance in epilepsy.
abstract: BACKGROUND
  One of the possible pathomechanisms of sudden death in epilepsy (SUDEP) is a postictal dysregulation of autonomic nervous system. We performed a heart rate variability (HRV) analysis of the periictal state to analyze whether a cardiac autonomic disturbance exists after an epileptic seizure.
  
  
  METHODS
  We included 31 periictal video-EEG-ECG recordings of 31 patients with epilepsy who had consecutively undergone pre-surgical evaluation. Nine generalized tonic-clonic (GTCS), 15 complex partial, and seven simple motor seizures were included. HRV was evaluated by analyzing 5-min-long ECG epochs, sampling from baseline, direct preictal, early-postictal (<15 min after the seizure), and late-postictal (5-6 h after the seizure) periods.
  
  
  RESULTS
  The heart rate was elevated immediately after the seizures, but 5-6 h postictally returned to the baseline level. Time-domain components of HRV decreased after the seizure and this decrease lasted for 5-6 h. Low-frequency power decreased in the early-postictal phase and high-frequency power of HRV dropped in the late-postictal phase. GTCS had an impact on short-term but not on long-term postictal HRV decrease.
  
  
  CONCLUSIONS
  We found decreased HRV immediately after the seizures, which lasted at least 5-6 h postictally, indicating a long-term postictal disturbance of the autonomous nervous system. GTCS were accompanied by a more decreased HRV than other seizures. Our results may have relevance in explaining pathomechanism of SUDEP.
authors.affiliation: Department of Neurology, University of Pécs, Pécs, Hungary.
authors.forename: V
authors.initials: V
authors.lastname: Toth
authors.forename: L
authors.initials: L
authors.lastname: Hejjel
authors.forename: A
authors.initials: A
authors.lastname: Fogarasi
authors.forename: C
authors.initials: C
authors.lastname: Gyimesi
authors.forename: G
authors.initials: G
authors.lastname: Orsi
authors.forename: A
authors.initials: A
authors.lastname: Szucs
authors.forename: N
authors.initials: N
authors.lastname: Kovacs
authors.forename: S
authors.initials: S
authors.lastname: Komoly
authors.forename: A
authors.initials: A
authors.lastname: Ebner
authors.forename: J
authors.initials: J
authors.lastname: Janszky
mesh_terms: D000328:Adult; D001341:Autonomic Nervous System / Q000503:physiopathology; D003645:Death, Sudden; D004562:Electrocardiography; D004569:Electroencephalography; D004827:Epilepsy / Q000503:physiopathology*; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male