Electrocardiograph QT lengthening associated with epileptiform EEG discharges – A role in sudden unexplained death in epilepsy?
Tavernor SJ, Brown SW, Tavernor RM, and Gifford C (1996) Electrocardiograph QT lengthening associated with epileptiform EEG discharges – A role in sudden unexplained death in epilepsy? Seizure 5:1 79–83.
Abstract: EEG with co-registered electrocardiography was recorded during at least two interictal epileptiform EEG discharges in each of 11 patients who later suffered from sudden unexpected death in epilepsy (SUDEP), and from another 11 age and sex matched patients, also with uncontrolled tonic-clonic seizures, drawn from the same centre who were still alive at the time of investigation (non-SUDEPs). A corrected QT interval for rate (QTc) was obtained and a mean value calculated for the period immediately prior to discharge, during discharge and immediately post discharge. Mean QTc was also obtained interictally without discharge. There was a significant (P = 0.01) increase in the mean QTc during discharge compared to that measured interictally without discharge for the whole population of SUDEPs and non-SUDEPs, and this was maintained for the SUDEPs alone (P = 0.02) but did not hold for the non-SUDEP group alone. Although reaching statistical significance, increases in mean QTc in SUDEP patients only exceeded currently accepted upper limits in one case, and then only marginally. The clinical significance of these findings merits further investigation.
Keywords: epilepsy; sudden unexplained death; electrocardiography; QTc interval; interictal epileptiform discharge; EEG.
- Retrospective study of simultaneous EEG and EKG data from 11 patients who later suffered SUDEP, with control group of living age- and sex-matched patients with uncontrolled GTCS. Corrected QT interval during seizure was significantly increased relative to baseline in both groups, but the increase persisted only in SUDEP patients. For further discussion of QT intervals see annotation at Aurlien et al.