The yield of long-term electrocardiographic recordings in refractory focal epilepsy

Epilepsia. 2019 Nov;60(11):2215-2223. doi: 10.1111/epi.16373. Epub 2019 Oct 21.

Abstract

Objective: To determine the incidence of clinically relevant arrhythmias in refractory focal epilepsy and to assess the potential of postictal arrhythmias as risk markers for sudden unexpected death in epilepsy (SUDEP).

Methods: We recruited people with refractory focal epilepsy without signs of ictal asystole and who had at least one focal seizure per month and implanted a loop recorder with 2-year follow-up. The devices automatically record arrhythmias. Subjects and caregivers were instructed to make additional peri-ictal recordings. Clinically relevant arrhythmias were defined as asystole ≥ 6 seconds; atrial fibrillation < 55 beats per minute (bpm), or > 200 bpm and duration > 30 seconds; persistent sinus bradycardia < 40 bpm while awake; and second- or third-degree atrioventricular block and ventricular tachycardia/fibrillation. We performed 12-lead electrocardiography (ECG) and tilt table testing to identify non-seizure-related causes of asystole.

Results: We included 49 people and accumulated 1060 months of monitoring. A total of 16 474 seizures were reported, of which 4679 were captured on ECG. No clinically relevant arrhythmias were identified. Three people had a total of 18 short-lasting (<6 seconds) periods of asystole, resulting in an incidence of 2.91 events per 1000 patient-months. None of these coincided with a reported seizure; one was explained by micturition syncope. Other non-clinically relevant arrhythmias included paroxysmal atrial fibrillation (n = 2), supraventricular tachycardia (n = 1), and sinus tachycardia with a right bundle branch block configuration (n = 1).

Significance: We found no clinically relevant arrhythmias in people with refractory focal epilepsy during long-term follow-up. The absence of postictal arrhythmias does not support the use of loop recorders in people at high SUDEP risk.

Keywords: ECG; cardiac arrhythmias; epilepsy; implantable loop recorders; sudden unexpected death in epilepsy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Arrhythmias, Cardiac / diagnosis
  • Arrhythmias, Cardiac / physiopathology
  • Drug Resistant Epilepsy / diagnosis*
  • Drug Resistant Epilepsy / epidemiology
  • Drug Resistant Epilepsy / physiopathology*
  • Electrocardiography / methods
  • Electrocardiography / trends*
  • Epilepsies, Partial / diagnosis*
  • Epilepsies, Partial / epidemiology
  • Epilepsies, Partial / physiopathology*
  • Female
  • Follow-Up Studies
  • Humans
  • Male
  • Middle Aged
  • Sudden Unexpected Death in Epilepsy / epidemiology
  • Time Factors
  • Young Adult