Abstracts

Rationale: Epileptic seizures are associated with many autonomic changes. Of those, ictal cardiovascular abnormalities received most of the attention because of their possible relation to SUDEP. We studied ictal and immediate postictal heart rate changes in a group of patients with different seizure. We tried to find a relationship between different seizure types and certain heart rate (HR) changes. Methods: We retrospectively studied 110 seizures in 62 patients. All patients underwent prolonged video-EEG monitoring for minimum of 24 hours. We categorized patients according to their location of seizure onset: temporal (right and left), frontal (right and left), temporoccipital (right and left), occipital (right and left), frontotemporal (right and left), central or generalized. Also we had a separate group of 35 patients with 55 psychogenic non-epileptic seizures (PNES). Baseline HR was obtained at 60-120 seconds prior to seizures onset, clinically or electrographically, whichever came first. Ictal HR was calculated between 30th to 60th seconds if seizure was longer than 1 minute as 15 seconds segments multiplied by 4. If the seizure lasted less than 1 minute than we choose 15 second interval in the last half of the ictus. Postictal HR was calculated at 30 seconds after seizure ended. Ictal changes as increase or decrease more than 10 beats per minute compared to baseline were considered significant. Student t and x2 tests were used for statistical comparison and significant p value was set at 0.05. Results: Both mean ictal and postictal HR changes did not reach to significance in PNES group (p<.0001). Epileptic seizures were analyzed in detail. Twenty-nine of the patients were male (47%). Mean age was 39 (range 19-72). Mean HR was 74 (range 40-168), 109 (range 52-260) and 96 (range 40-220) for preictal, ictal and postictal respectively. There were 3 (1.8%) simple partial (SPS), 85 (51.5%) complex partial (CPS), 11 (6.7%) generalized tonic-clonic (GTC) and 11 (6.7%) subclinical seizures. Twenty patients had secondary generalization (2°GTC). There was no significant correlation between ictal HR changes and seizure location or lateralization. There was a significant correlation between CPS and increased heart rate (p:0.02). Subclinical seizures showed no variation at all in ictal or postictal HR which was significant compared to other seizure types (p:0.003). 2°GTC seizures were associated with both ictal and postictal HR changes which was significantly different than others (p<0.01). All patients with 2°GTC showed significantly increased postictal HR compared to 44 out of 90 patients without secondary generalization. Twelve patients had HR over 150 per minute ictally (2 over 200) of which 6 were in patients with 2°GTC. Six patients had HR over 150 postictally (2 over 200) of which 4 were with 2°GTC. Conclusions: PNES, in general, were not associated with any significant HR changes. CPSs were associated with increased HR during the seizure regardless of localization or lateralization. Secondary generalization was always associated with significant HR changes and can also lead to clinically significant tachycardia.