Abstracts

Rationale: The ictal arrhythmias well described in the literature include bradycardia, asystole, and atrial tachycardia. To our knowledge, peri-ictal ventricular tachycardia has not been previously described.

Methods: The patient is a 24-year-old woman with nocturnal generalized tonic-clonic seizures since 11 years of age, witnessed by her mother. The patient is amnestic for the events, but recognizes their occurrence based on tongue lacerations and urinary incontinence. She reported that her grandmother had seizures, which was her only epilepsy risk factor.

Prior outside EEG in 2015 and 2017, including a 2-day video EEG, were reportedly normal with no seizures captured. She also had outside MRIs in 2008 and 2011, which were reportedly normal. A routine EEG in 2019 and a 24-hour ambulatory EEG in 2020, both completed at the University of Connecticut, showed rare, sleep-activated left temporal sharp wave discharges, but no seizures were captured. During these EEGs, the patient was taking levetiracetam ER 2000 mg daily (serum concentration=16 mg/L). She was then admitted to the Epilepsy Monitoring Unit at the University of Connecticut in 2021.

Results: During the Epilepsy Monitoring Unit admission, four nocturnal seizures were captured. All of the seizures had left temporal (T3-T5) onset. The first three seizures remained localized to the left hemisphere, and the fourth seizure generalized. Ictal behavior was consistent with temporal lobe seizures: several eye blinks were followed by oral automatisms, vocalization with head version to the right, and progression to a tonic-clonic phase. Following the generalized seizure, approximately 50 seconds after onset of postictal suppression, the heart rate increased from 90 bpm at baseline to 120 bpm. The QRS complexes changed morphology over the next 3 seconds, and the patient developed ventricular tachycardia (140 bpm) lasting 20 seconds (Figure 1). The ventricular tachycardia spontaneously resolved into sinus tachycardia at 140 bpm (Figure 2). The patient’s serum potassium concentration was normal (4.0). Her resting EKG was also normal, with a corrected QT interval 332 msec.

Conclusions: Postictal ventricular tachycardia has not been previously reported. Peri-ictal ventricular tachycardia has therapeutic significance related to the prevention of cardiac death and may require implantation of a defibrillator. Directions for further investigation in this patient include establishing the frequency of such episodes and detection of possible ion channel mutations predisposing to arrhythmias.

Funding: Please list any funding that was received in support of this abstract.: No.