Abstracts

Heart rate (HR) changes are common in epileptic and nonepileptic seizures. A previous study suggested that a 30% cut-off of HR increase could separate nonconvulsive epileptic seizures from nonconvulsive nonepileptic events but HR analysis was only performed during the initial ictal and postictal periods and details of concomitant EEG changes and nonconvulsive epileptic auras were not included (Neurology 2002;58:636). Therefore, the aim of this study was to evaluate the progression of HR changes in the pre-ictal, ictal and post-ictal phases in patients with dialeptic temporal lobe epilepsy (TLE), nonconvulsive nonepileptic seizures and dialeptic-like nonconvulsive epileptic auras.
Twenty-seven patients (11 men, 16 women) had 59 dialeptic seizures/auras recorded during inpatient video EEG-EKG monitoring, retrospectively evaluated and classified in: classic TLE with well-formed theta rhythm on scalp recordings (N=28 events), nonepileptic nonconvulsive events (N=20) or nonconvulsive (dialeptic-like) auras in TLE patients without scalp EEG changes (N=11). HR was measured by counting QRS complexes in 10s epochs every 1 min, 1h before, during and 1h after EEG end of each event (total analysis of 2h+event duration). One-Way ANOVA for repeated measures and Bonferroni test were used for the comparisons (mean[plusmn]SEM), with P[lt]0.05.
Mean age was 34.9[plusmn]2 years and similar (P[gt]0.05) in the 3 groups: 40.7[plusmn]2.4 (nonepileptic), 34.2[plusmn]4.8 (auras) and 31.2[plusmn]2.9 (TLE). Sex and history of smoking were also similar in the 3 groups (P[gt]0.05). No patient had history of coronary artery disease or arrhythmia. Obesity was not particularly more prevalent in any group (P[gt]0.05). Baseline HR was similar (P[gt]0.05) in psychogenic (74.6[plusmn]1.4) and TLE (72.7[plusmn]2.5) but was increased in aura events: 86.1[plusmn]2.6 beats/min (P[lt]0.05). During or after each psychogenic event, HR did not increase significantly: 77.6[plusmn]1.9 and 76[plusmn]1.6 beats/min respectively (P[gt]0.05). HR also remained unchanged during or after each aura event: 91.2[plusmn]2.6 and 88.4[plusmn]3 beats/min (P[gt]0.05). However, during each TLE event, HR was significantly increased to 109.4[plusmn]3.2 beats/min (P[lt]0.05), returning to baseline in the post ictal phase: 81.9[underline]+2[/underline].4 beats/min. No events with bradycardia were observed. Fifty-five % of the TLE events started on the right and 45% on the left, with 100% contralateral hemisphere spreading.
HR increases significantly in dialeptic TLE and not in nonconvulsive (dialeptic-like) nonepileptic events. A baseline state of enhanced HR may precede the self-perception of dialeptic epileptic auras in TLE. HR analysis can differentiate dialeptic TLE from non-epileptic events and epileptic auras.