Epileptic patients who survived sudden cardiac death have increased risk of recurrent arrhythmias and death.
BACKGROUND
Cardiac arrhythmogenesis and cryptogenic epilepsy can be due to ion channel dysfunction and may coexist in the same patient. Sudden unexplained death in epilepsy (SUDEP) is a known entity with unknown cause, with the possibility of ventricular tachyarrhythmias being one of the causes. However, no prior study has investigated epileptic survivors of sudden cardiac death (SCD), recurrent life-threatening ventricular tachyarrhythmia (LTVA) and other outcomes in this patient population.


METHODS
The Antiarrhythmics Versus Implantable Cardioverter Defibrillators (AVID) Trial (n = 1016) was a multicenter trial comparing a cardioverter-defibrillator device (ICD) (n = 507) and anti-arrhythmic drugs (AADs) (n = 499) for secondary prevention of LTVAs. Mean follow-up duration was 916 ± 471 days per patient. Patients with a history of epilepsy (n = 6) in the ICD arm were included in this analysis. End points were recurrence of LTVA, cardiac death and all-cause mortality.


RESULTS
History of epilepsy (n = 6) was a significant predictor of recurrent LTVA [hazard ratio 3.53, 95% confidence interval (CI) 1.30-9.56], cardiac death (hazard ratio 4.14, 95% CI 1.30-13.14) and all-cause mortality (hazard ratio 3.82, 95% CI 1.40-10.48) in the ICD arm (n = 498). This relationship remained unchanged on multivariate analysis after controlling for baseline clinical differences.


CONCLUSIONS
This is the first study to investigate the effect of epilepsy on secondary prevention of LTVA. Epileptic survivors of SCD are at significantly greater risk of recurrent arrhythmias and death as compared to other survivors of recurrent LTVA. Role of coexisting channelopathies in both epilepsy and arrhythmogenesis may explain SUDEP and requires further investigation.
Badheka
Apurva
A
Division of Cardiology/Electrophysiology, Department of Internal Medicine, Wayne State University, Detroit, Michigan 48201, USA.
Rathod
Ankit
A
Kizilbash
Mohammad A
MA
Lai
Zongshan
Z
Mohamad
Tamam
T
Shah
Aashit
A
Afonso
Luis
L
Jacob
Sony
S
D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use*; D016757:Death, Sudden, Cardiac / Q000209:etiology / Q000517:prevention & control*; D017147:Defibrillators, Implantable; D004554:Electric Countershock / Q000295:instrumentation; D004827:Epilepsy / Q000150:complications* / Q000401:mortality; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D016016:Proportional Hazards Models; D016032:Randomized Controlled Trials as Topic; D012008:Recurrence; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D055502:Secondary Prevention / Q000379:methods*; D017180:Tachycardia, Ventricular / Q000209:etiology* / Q000401:mortality / Q000517:prevention & control; D013997:Time Factors; D016896:Treatment Outcome
D000889:Anti-Arrhythmia Agents