Introduction: Seizures are symptoms associated with abnormal electrical activity in
electroencephalogram (EEG). The present study was designed to determine the effect of absence
seizure on heart rate (HR) changes in electrocardiogram (ECG).
Methods: HR alterations were recorded simultaneous with spike and wave discharges (SWD)
by EEG in 6 WAG/Rij rats as a well characterized and validated genetic animal epilepsy model.
Moreover, 6 control rats were used to distinguish the differences of HR changes between various
groups. Electrodes were placed on the skull and under the chest skin, minimizing time delay and
signal attenuation. HR was calculated by an adaptable algorithm based on continues wavelet
transform (CWT) particular for this study. Three main features of HR minimum, maximum, and
mean values were estimated for pre-ictal and ictal intervals for all seizures.
Results: ECG beats detected with sensitivity of 99.9% and positive predictability of 99.8% based
on CWT. HR deceleration was found in 86% of the seizures. There were statistically significant
(P<0.001) reductions of these values from pre-ictal to ictal intervals. Interictal HR acceleration
and ictal deceleration were the major feature of alterations and in 23% of seizures, this decrease
had priority to the onsets.
Discussion: These findings may lead to design a seizure alarm system based on HR and to obtain
new insights about sudden unexpected death in epilepsy (SUDEP) phenomenon and side-effects
of antiepileptic drugs (AED).
Type of Study:
Original |
Subject:
Computational Neuroscience Received: 2014/11/8 | Accepted: 2015/03/2 | Published: 2015/04/1