Electrocardiographic features of sudden unexpected death in epilepsy

Abstract

is an early career clinician-investigator in cardiac electrophysiology. SUMMARYSudden unexpected death in epilepsy (SUDEP) is the most common cause of epilepsyrelated mortality. We hypothesized that electrocardiography (ECG) features may distinguish SUDEP cases from living subjects with epilepsy. Using a matched case-control design, we compared ECG studies of 12 consecutive cases of SUDEP over 10 years and 22 epilepsy controls matched for age, sex, epilepsy type (focal, generalized, or unknown/mixed type), concomitant antiepileptic, and psychotropic drug classes. Conduction intervals and prevalence of abnormal ventricular conduction diagnosis (QRS ≥110 msec), abnormal ventricular conduction pattern (QRS <110 msec, morphology of incomplete right or left bundle branch block or intraventricular conduction delay), early repolarization, and features of inherited cardiac channelopathies were assessed. Abnormal ventricular conduction diagnosis and pattern distinguished SUDEP cases from matched controls. Abnormal ventricular conduction diagnosis was present in two cases and no controls. Abnormal ventricular conduction pattern was more common in cases than controls (58% vs. 18%, p = 0.04). Early repolarization was similarly prevalent in cases and controls, but the overall prevalence exceeded that of published community-based cohorts.

Acquired cardiac channelopathies in epilepsy: Evidence, mechanisms, and clinical significance

“…This was consistent with earlier evidence of a correlation between SUDEP risk and lower RMSSD (Root Mean Square of Successive Differences), reflecting depressed vagal modulation of heart rate variability . However, other studies comparing suspected SUDEP cases with matched epilepsy controls revealed no difference in resting ECG measures or heart rate variability …”

“…91 However, other studies comparing suspected SUDEP cases with matched epilepsy controls revealed no difference in resting ECG measures or heart rate variability. 92,93 Elucidating the role of altered cardiac ion channel expression in SUDEP is complicated by uncertainties surrounding the circumstances of SUDEP itself. First, it is difficult to ascertain the cardiac contribution to SUDEP events given their multifactorial pathophysiology.…”

Mortality with brainstem seizures from focal 4‐aminopyridine–induced recurrent hippocampal seizures

“…SUDEP often occurs in younger people with incompletely controlled epilepsy and likely results from seizure‐induced cardiac and respiratory dysfunction. There is evidence that cardiac dysfunction contributes to SUDEP, with myocyte hypertrophy and focal myocardial fibrosis commonly seen pathologically, and compared to control cases, there are significantly more cardiac channelopathy mutations and abnormal ventricular conduction patterns in SUDEP cases. Respiratory mechanisms are more directly implicated in SUDEP .…”

Prevention of Sudden Unexpected Death in Epilepsy

“…another study found that when comparing abnormal ventricular conduction diagnosis and pattern (QRS <110 msec, morphology of incomplete right or left bundle branch block or intraventricular conduction delay) it was possible to distinguish 12 SUDEP cases from 22 matched controls. 56 Other potential biomarkers include inter-ictal and peri-ictal cardiac and autonomic dysfunction. 57 Genetic factors may also help identify patients at risk of SUDEP.…”