Spectral Analysis of Heart Rate Variability during Sleep in Children with Partial Epilepsy.
Abstract number :
1.093
Submission category :
Year :
2001
Submission ID :
316
Source :
www.aesnet.org
Presentation date :
12/1/2001 12:00:00 AM
Published date :
Dec 1, 2001, 06:00 AM
Authors :
A.A. Arzimanoglou, MD, Child Neurology and Metabolic Diseases Dpt., University Hospital Robert Debre and INSERM E9935, Paris, France; R. Ferri, MD, Sleep Research Center and Dpt. of Neurology, IRCCS, Troina, Italy; L. Curzi-Dascalova, MD, Physiologie Dpt.
RATIONALE: Alterations of the autonomic control of cardiac activity in epileptic patients have been reported by several studies in the past an both ictal and interictal modifications of heart rate regulation have been described. Also, alterations of the autonomic control of cardiac activity can play an important role in the sudden unexplained death in patients with epilepsy (SUDEP). However, the eventual presence of specific changes in HRV during sleep, not correlated with seizures, has not been assessed in children with epilepsy; for this reason, we evaluated the features of the cardiac autonomic function during sleep without ictal epileptiform EEG activity in a group of children with partial epilepsy.
METHODS: Eleven patients (5 males and 6 females; mean age 11.5 years, S.D. 3.65 years) affected by partial epilepsy were admitted to this study; 11 normal subjects (5 males and 6 females; mean age 12.9 years, S.D. 2.72 years) served as a control group. All subjects slept in the laboratory for two consecutive nights. The data were analyzed during the second night. Sleep was polygraphically recorded (including one ECG channel) and signals were digitally stored. A series of 5-minute ECG epochs were chosen from each sleep stage, during periods without evident ictal epileptiform activity in the EEG. ECG signals were analyzed for automatic detection of R waves and, subsequently, a series of time- and frequency-domain measures were calculated.
RESULTS: Epileptic subjects tended to show an overall lower HRV in both time- and frequency-domain parameters, mostly during REM sleep and, to a lesser extent, during sleep stage 2. Among the different bands, this decrease was most evident for HF absolute power. For this reason, the LF/HF ratio was always higher in epileptic patients than in normal controls and the difference was statistically significant during SWS and REM sleep.
CONCLUSIONS: Our results seem to indicate that during sleep, a particular condition of basal modification in autonomic asset occurs (mostly during REM sleep) in partial epilepsy patients; this might represent an important factor contributing to the complex mechanism of SUDEP which takes place most often during sleep and supports the need of studying HRV, specifically during this state, in epileptic patients.