Abstracts

Rationale: Several studies aimed at identifying biomarkers for risk stratification of sudden unexpected death in epilepsy (SUDEP) have raised the possibility of a relatively prolonged QTc1, 2. Reports demonstrating a relatively longer QTc in epilepsy patients have compared normal controls with a heterogeneous group of epilepsy patients1, 2. In our study we compared the resting ECG findings in temporal lobe epilepsy patients (TLE) to psychogenic nonepileptic seizures (PNES) patients. Methods: We retrospectively reviewed our database of all patients admitted to the epilepsy monitoring unit between January 2004 and March 2008. Patients with the diagnosis of TLE and PNES were identified. All consecutive patients who had routine 12 leads ECG were included in the analysis. We excluded patients with a history of hypertension, coronary artery disease and cardiac arrhythmia. Demographics, body weight, number of AED and ECG findings including QTc interval were collected. Statistical analysis utilizing Chi square and t-test were performed. Results: A total of a hundred twenty five patient’s records were reviewed. Forty one patients were excluded (12 had no recorded weight; 10 had no recorded ECG and 19 had a medical history of cardiovascular disease and cardiac arrhythmia). Sixty two patients had TLE age range 18- 77 years and 22 diagnosed with PNES age range between 19-57 yrs. There is no significant difference between the two groups in age, AED use, and body weight or sex distribution; however there is a trend towards old age in TLE. The resting ECG findings showed the mean QTc was significantly shorter in the TLE group compared to PNES (411 vs 420 respectively)p=0.02, however there were no significant differences between the two groups in heart rate, PR interval or QRS duration. Conclusions: This study demonstrates that QTc interval is relatively shorter in this homgenous group of patients with TLE and contradicts the prior reports of relatively prolonged QTc interval in TLE patients. Furthermore, shorter duration of QTc has been associated with rapid repolarization and sudden death. Further understanding of the effects of epilepsy on the myocardium and its long term electrophysiology may help identify cardiac biomarkers for SUDEP.