Sudden cardiac arrest associated with early repolarization.
BACKGROUND
Early repolarization is a common electrocardiographic finding that is generally considered to be benign. Its potential to cause cardiac arrhythmias has been hypothesized from experimental studies, but it is not known whether there is a clinical association with sudden cardiac arrest.


METHODS
We reviewed data from 206 case subjects at 22 centers who were resuscitated after cardiac arrest due to idiopathic ventricular fibrillation and assessed the prevalence of electrocardiographic early repolarization. The latter was defined as an elevation of the QRS-ST junction of at least 0.1 mV from baseline in the inferior or lateral lead, manifested as QRS slurring or notching. The control group comprised 412 subjects without heart disease who were matched for age, sex, race, and level of physical activity. Follow-up data that included the results of monitoring with an implantable defibrillator were obtained for all case subjects.


RESULTS
Early repolarization was more frequent in case subjects with idiopathic ventricular fibrillation than in control subjects (31% vs. 5%, P<0.001). Among case subjects, those with early repolarization were more likely to be male and to have a history of syncope or sudden cardiac arrest during sleep than those without early repolarization. In eight subjects, the origin of ectopy that initiated ventricular arrhythmias was mapped to sites concordant with the localization of repolarization abnormalities. During a mean (+/-SD) follow-up of 61+/-50 months, defibrillator monitoring showed a higher incidence of recurrent ventricular fibrillation in case subjects with a repolarization abnormality than in those without such an abnormality (hazard ratio, 2.1; 95% confidence interval, 1.2 to 3.5; P=0.008).


CONCLUSIONS
Among patients with a history of idiopathic ventricular fibrillation, there is an increased prevalence of early repolarization.
Haïssaguerre
Michel
M
Université Bordeaux, Hôpital Haut-Lévêque, Bordeaux-Pessac, France. michel.haissaguerre@chu-bordeaux.fr
Derval
Nicolas
N
Sacher
Frederic
F
Jesel
Laurence
L
Deisenhofer
Isabel
I
de Roy
Luc
L
Pasquié
Jean-Luc
JL
Nogami
Akihiko
A
Babuty
Dominique
D
Yli-Mayry
Sinikka
S
De Chillou
Christian
C
Scanu
Patrice
P
Mabo
Philippe
P
Matsuo
Seiichiro
S
Probst
Vincent
V
Le Scouarnec
Solena
S
Defaye
Pascal
P
Schlaepfer
Juerg
J
Rostock
Thomas
T
Lacroix
Dominique
D
Lamaison
Dominique
D
Lavergne
Thomas
T
Aizawa
Yoshifusa
Y
Englund
Anders
A
Anselme
Frederic
F
O'Neill
Mark
M
Hocini
Meleze
M
Lim
Kang Teng
KT
Knecht
Sebastien
S
Veenhuyzen
George D
GD
Bordachar
Pierre
P
Chauvin
Michel
M
Jais
Pierre
P
Coureau
Gaelle
G
Chene
Genevieve
G
Klein
George J
GJ
Clémenty
Jacques
J
D000206:Actuarial Analysis; D000328:Adult; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001145:Arrhythmias, Cardiac / Q000453:epidemiology; D054849:Cardiac Electrophysiology; D016022:Case-Control Studies; D017115:Catheter Ablation; D016757:Death, Sudden, Cardiac / Q000209:etiology*; D017147:Defibrillators, Implantable; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012008:Recurrence; D018709:Statistics, Nonparametric; D014693:Ventricular Fibrillation / Q000150:complications / Q000503:physiopathology* / Q000628:therapy
D000889:Anti-Arrhythmia Agents