is a group of conditions with
abnormal heart rhythm. Arrhythmias commonly occur during or soon after a
seizure. Seizure-related cardiac arrhythmias have been considered as the major
causes of Sudden Unexpected Death in Epilepsy (SUDEP).
A new study published in Journal of
Neurology, Neurosurgery and Psychiatry
has attempted to identify
characteristics of various cardiac arrhythmias during and after epileptic seizures
. Researchers conducted a systematic review on cardiac arrhythmia occurring in epilepsy cases published in PubMed, EMBASE (OVID
version), Web of Science and the Cochrane Library databases.
The researchers found
that ictal asystole - transient stopping of the heartbeats during a seizure - was
the most frequently reported pattern.
After a systematic selection
procedure, the researchers reviewed 178 full-text articles. Also, only cases
with simultaneous video-EEG (vEEG) recordings which demonstrated the seizure
activity were selected for the review. Researchers recorded whether the arrhythmia
was during or soon after the seizure for each individual case.
For each case, variables including age, gender, type of
, duration of epilepsy and
seizure frequency were included. The researchers also noted number of
antiepileptic drugs taken, type of antiepileptic drugs taken, brain MRI,
seizure type associated with cardiac arrhythmia, duration of arrhythmia, and
cardiac history among other details.
To understand the findings, here are a few relevant
- Related to seizure
- Following a seizure
- Slowing of heart rate
- Transient stopping of
Atrial Flutter / Fibrillation
- Irregular and rapid
contractions of the atria or the upper chambers of the heart
- Irregular and rapid
contractions of the ventricles or the lower chambers of the heart
- Failure of electrical
impulses to pass from the atria to the ventricles
distinct patterns of ictal and postictal cardiac arrhythmias were identified in
the study. This includes a total of 103 cases of ictal asystole and 25 ictal
bradycardia cases. Other patterns identified are: 3 postictal ventricular
fibrillation cases, 2 postictal AV-conduction block cases, 14 atrial flutter /
atrial fibrillation cases, 13 postictal asystole cases, and 11 ictal
atrioventricular (AV) - conduction block - cases.
- Ictal AV-conduction block, asystole
and bradycardia were self-limiting in most cases.
They were also seen during focal dyscognitive seizures - a type of seizure in
which the person may appear unresponsive - in patients with a type of epilepsy
called temporal lobe epilepsy.
- Postictal arrhythmias seem of more
importance in causing Sudden Unexpected Death in Epilepsy, rather than ictal arrhythmias,
since some of them were associated with sudden deaths. The researchers also
suggest that the mechanisms of ictal and postictal arrhythmias are likely to be
different, since they differed in timing, associated seizure types and
1. van der Lende M, Surges R, Sander JW, Thijs RD. Cardiac arrhythmias during or after epileptic seizures. J Neurol Neurosurg Psychiatry doi:10.1136/jnnp-2015-310559