Abstracts

Changes in cardiovascular tone is noted in Temporal Lobe Epilepsy [TLE] patients. Surgical removal of the foci might alter the equation of epileptogenicity and autonomic controls. In this study, two groups of epilepsy patients were studied: 1) Those that were under medication and seizure free for at least a period of last three months, i.e. well-controlled (WC) and 2) Those that were intractable. Both the groups underwent a battery of autonomic function tests which were aimed at testing their autonomic reactivity. Baseline autonomic activity (tone) was also measured by Heart rate variability (HRV) analysis. Autonomic functions were compared between 18 WC patients (mean age 23.67[plusmn] 12.62, 11 males and 7 females) and 10 IE patients (mean age 22.9[plusmn] 10.8, 9 males and 1 female). WC group showed higher values as compared to the IE group i.e. E: I ratio (1.41[plusmn] 0.19 vs. 1.3[plusmn] 0.12), delta HR changes during DBT ( 26.56 [plusmn]11.5 vs. 21.8[plusmn]8.27), tachycardia ratio (1.38[plusmn]0.2 vs. 1.34[plusmn]0.14), bradycardia ratio (0.79[plusmn] 0.12 vs. 0.7[plusmn]0.17), 30: 15 ratio of the HUT (1.21[plusmn]0.38 vs. 1.1[plusmn]0.05), except the Valsalva ratio (VR) (1.8[plusmn]90.44 vs. 2.06[plusmn]0.48), this denotes a trend towards a lower parasympathetic reactivity in the intractable epileptic group. Among the indices for sympathetic reactivity which were studied, i.e. rise in diastolic B.P during HGT (20.59[plusmn] 8.85 vs. 23.6[plusmn]7.65), rise in diastolic BP during CPT ( 13.29[plusmn]8.03 vs. 13.56[plusmn]7.54) exhibited higher values in the IE group.
i.e. suffered from recurrent seizures despite optimal treatment under an experienced neurologist over a period of more than one year (IE) Previous studies have shown that epileptic patients exhibit varied autonomic responses, either as part of seizure symptoms or as interictal manifestations which possibly result from propagation of electrical impulses from the seizure focus to the central autonomic nuclei. The time domain measures which give an idea of parasympathetic tone, i.e. SDNN (44.5[plusmn]927.4 vs. 28.96[plusmn]6.86), SDSD (46.68[plusmn]34.4 vs. 22.58[plusmn]7.62), RMSSD (46.61[plusmn]34.35 vs. 22.55[plusmn]7.61) NN50 (38.534[plusmn]1.97 vs. 9.710[plusmn].26) and pNN50 (11.04[plusmn]12.74 vs. 2.53[plusmn]2.8) consistently showed lower values in IE group as compared to WC group, which suggests a lower parasympathetic tone when compared to the WC group. In the frequency domain measures, LF(nu) (40.13[plusmn]13.72 vs. 45.95[plusmn]20.47), %LF (30.64[plusmn] 7.57 vs. 27.821[plusmn]3.13)and LF/HF ratio (1.030[plusmn].58 vs. 1.43 +/- 1.08) showed that the IE group had a higher sympathetic tone while the HF(nu) (46.55[plusmn]16.86 vs. 44.39[plusmn]19.55), showed that this group also had a lower parasympathetic tone when compared to the WC group. The intractable group had both a higher basal sympathetic tone and sympathetic reactivity when compared to the well-controlled group.