Electrocardiographic changes during electrographic seizures
M. J. Keilson, W. A. Hauser and J. P. Magrill
Division of Neurology, Maimonides Medical Center, Brooklyn, NY 11219.
The occurrence of high-risk cardiac arrhythmias during electrographic
seizures has been proposed as a possible cause for sudden unexpected death
in patients with epilepsy. Several anecdotal case reports have documented
various cardiac irregularities during seizures. We reviewed simultaneous
24-hour electroencephalographic - electrocardiographic studies obtained by
ambulatory cassette electroencephalography in 45 patients who experienced
106 electrographic seizures. An increase in heart rate was seen in 96% of
seizures, while in four seizures, the rate was unchanged. Heart rate
increase measured from 1 minute preictally to intraictal peak ranged from
0% to 160% (mean, 60%). The onset of tachycardia was usually within several
seconds (before or after) of the seizure onset, and often persisted for
several minutes after termination of the discharge. No difference was found
in patients with lateralized vs generalized seizures. Neither ventricular
ectopia, conduction defects, or bradycardia were observed during the ictal
episodes. We conclude that ictal tachycardia is the rule during
electrographic seizures, and that high-risk cardiac arrhythmias are
uncommon.
