Abstracts

Rationale: Autonomic dysfunction is commonly associated with seizures and can affect cardiopulmonary, gastrointenstinal and other systems. Seizures frequently affect the heart rate and rhythm, often in a transient manner. An increase in heart rate is more commonly encountered with seizures, however ictal bradycardia and asystole have also been described. The existence of a heart homunculus in the insula is well recognized. Injuries to the insula may cause arrhythmias, and sudden cardiac death in epilepsy has been postulated as cardiogenic in nature, as evidenced by presence of contraction band necrosis indicating catecholamine storm to the myocardium. Occasionally, this brain-heart connection can be demonstrated live on video EEG. We present a recent case of a patient with a left meningioma resection, who had two instances of asystole that began with left frontal seizures. Methods: Long-term video EEG monitoring was performed on a patient in the neurological ICU who failed to recover from anesthesia after the resection of a left frontal meningioma. The EEG was analyzed by an expert epileptologist. Results: The EEG was significantly asymmetric, with attenuation and slowing over the left hemisphere, and rare trains of epileptogenic activity over the left hemisphere. Subtle left frontal seizures were noted twice, preceding, in one case, a complete asystole requiring CPR, and, on the next day, a long asystolic pause.. The seizures quickly spread to the contralateral hemisphere. There was a subtle clinical correlate of left arm and head myoclonic jerking. Diffuse EEG suppression followed the asystole. The patient received a pacemaker,and has remained stable since then. Conclusions: The insula is a deep structure, and scalp correlate to an insular seizure is likely to be a frontal or a temporal EEG ictal discharge. Clinical manifestations of insular seizures are varied, and can include autonomic, speech, or motor phenomena. Additionally, there are multiple reports of arrhythmias, sometimes of a fatal nature, arising in the setting of seizures involving either left or right insula. There are also studies which suggest that autonomic control shows hemispheric lateralization, with the right hemisphere predominantly modulating sympathetic tone, and the left hemisphere parasympathetic tone. However, reports of right or left sided seizures causing specific EKG abnormalities have not been consistent. In this case, subtle but unequivocal left fronto-temporal rhythmicity preceded the asystole. It was otherwise absent from the record. It is feasible to postulate that left frontal seizures originating from a known lesion reached the insulae, and caused cardiac pause and/or asystolic arrest. This case study highlights the need for continuous video EEG monitoring in ICU patients, and for further exploration of the brain-heart connection. Funding: None.