Abstracts

Rationale: Temporal lobectomy is a procedure used to treat patient with drug resistant temporal epilepsy. This study is aimed to investigate autonomic changes following temporal lobe resection. Specifically, this protocol focused on irregularity between heart beat known to depend on the synergic activities between sympathetic and para-sympathetic systems and their central regulation [1] Methods: One patient with drug resistant epilepsy ongoing temporal lobectomy and 4 healthy subjects were included in this study. At first, the subjects were asked to respond the SCOPA-autonomic questionnaire.  Then, their heart rate and blood pressure were monitored in supine position. Patients were tested prior- surgery and one month after without change in medication. Heart rate variability (R-R intervals) was analyzed in time, frequency and non-linear domains. Features of heart rate variability of patients were compared prior and after surgery and to healthy subjects. Results: Preliminary data show that Autonomic dysfunctions as measured by the SCOPA were decreased by 42% following temporal lobectomy and pre-/post-assessment were in the 1st-99th percentile range of the control population. HRV analyses show that temporal lobectomy affects heart rate variability in time (+59% coefficient variation), frequency (+3.2dB in high/low frequency ratio) and non-linear domain (-3% Entropy). With the exception of the coefficient variation, HRV features were contained in the 1st-99th percentile range of the control population. Conclusions: Temporal lobectomy increased HRV as a result of an increased low oscillation (partially sympathetic mediated) which may be related to the loss of inter-ictal pathological activities in the autonomic network [2, 3] and/or a disruption of downstream activity from the insular cortex to the peripheral autonomic system. Clinically relevant, the decrease of self-reported autonomic symptoms by patients following temporal lobectomy indicates some awareness of epileptic patients about their changes in autonomic functions. A larger study is needed to confirm this finding.1.               Darbin, O. and D.K. Naritoku, Pharmacologic evidence for a parasympathetic role in seizure-induced neurocardiac regulatory abnormalities. Epilepsy Behav, 2004. 5(1): p. 28-30.2.               Darbin, O., D. Casebeer, and D.K. Naritoku, Effects of seizure severity and seizure repetition on postictal cardiac arrhythmia following maximal electroshock. Exp Neurol, 2003. 181(2): p. 327-31.3.               Darbin, O., D.J. Casebeer, and D.K. Naritoku, Cardiac dysrhythmia associated with the immediate postictal state after maximal electroshock in freely moving rat. Epilepsia, 2002. 43(4): p. 336-41. Funding: None