Significant arrhythmias appear to be an under-reported consequence of epileptic seizures, and some patients may require placement of a cardiac pacemaker to prevent sudden cardiac death, according to an article in the December 18th issue of the Lancet. Patients with epilepsy are known to be at risk of sudden unexplained death. Irregular heart rhythm as a result of neurological dysfunction during seizures has been thought to be a possible cause.

John Duncan and his British colleagues studied 20 patients with epilepsy who received an implantable device which monitored heart rhythm. These devices were programmed to record automatically for bradycardia or tachycardia.

Patients were studied for up to 22 months; electrocardiographic patterns monitored heart rhythms during 377 seizures. Heart rate during habitual seizures exceeded 100 beats per minute among 16 patients. Four patients had bradycardia or periods of asystole and were given permanent pacemaker insertion. Three of these four patients had potentially fatal asystole.

Professor Duncan commented: “We have shown that implantable loop recorders can identify potentially fatal cardiac abnormalities in patients with epilepsy, and suggest that the incidence of bradycardia and asystole has previously been under-reported. Asystole underlies a proportion of sudden unexpected deaths in epilepsy, which could be prevented by cardiac-pacemaker insertion.”

In an accompanying commentary, physicians Lawrence J. Hirsch and W. Allen Houser considered the present study an important step forward but caution that it is too early to change clinical practice until larger confirmatory studies are conclusive.