Characterizing electrocardiographic changes during pre-seizure periods through temporal and spectral features

Epilepsy affects the autonomic nervous system, and changes in this function are known to occur during, and even before the electroencephalographic onset of the seizure. The aim of this study was to characterize autonomic changes during and before the epileptic seizures. The electrocardiographic signals from thirteen epileptic patients, were first pre-processed and then the RR series was extracted. The following segments were selected for the analysis: 15 min before seizure onset (preictal), seizure time frame (ictal) and 15 min far from the seizure (interictal). Temporal and frequency features were calculated. In addition, Recurrence Quantification Analysis (RQA) was performed. Significant differences were detected in time-domain and RQA parameters 15 min before seizures suggesting the possibility of an early prediction of seizure onset. In addition, significant changes were observed during seizure. Further studies are needed to confirm these preliminary results in a larger number of subjects.