title: Prevalence and characteristics of early repolarization in the CASPER registry: cardiac arrest survivors with preserved ejection fraction registry.
abstract: OBJECTIVE
  We evaluated the prevalence and characteristics of early repolarization in patients in CASPER (Cardiac Arrest Survivors With Preserved Ejection Fraction Registry).
  
  
  BACKGROUND
  Early repolarization has been implicated in a syndrome of polymorphic ventricular tachycardia and fibrillation in patients without organic heart disease.
  
  
  METHODS
  One hundred patients with apparently unexplained cardiac arrest and preserved ejection fraction underwent extensive clinical and genetic testing to unmask subclinical electrical or structural disease. A blinded independent analysis of the 12-lead electrocardiogram (ECG) was performed. Early repolarization was defined as ≥0.1 mV QRS-ST junction (J-point) elevation with terminal QRS slurring or notching in at least 2 contiguous inferior and/or lateral leads.
  
  
  RESULTS
  One hundred cardiac arrest patients were enrolled (40 females, age 43 ± 14 years). Forty-four were diagnosed with an established cause for cardiac arrest. Significant early repolarization was found in 19 patients, including 6 with a primary diagnosis that explained their cardiac arrest (14%), compared with 23% of the 56 patients with idiopathic ventricular fibrillation (IVF) (p = 0.23). J-point elevation in IVF patients had higher amplitude (0.25 ± 0.11 mV vs. 0.13 ± 0.05 mV, p = 0.02) and wider distribution (4.3 ± 1.3 leads vs. 2.8 ± 0.8 leads; p = 0.01) than those with an established cause of cardiac arrest. J-wave amplitude was fluctuant on serial ECGs; at least 1 ECG failed to demonstrate early repolarization in 58% of patients.
  
  
  CONCLUSIONS
  Early repolarization is present in a significant proportion of causally diagnosed and idiopathic VF. It is often intermittent and more pronounced in IVF patients. (Registry of Unexplained Cardiac Arrest; NCT00292032).
authors.affiliation: Hopital Haut Lévêque, CHU Bordeaux, University Bordeaux 2, Bordeaux, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Derval
authors.forename: Christopher S
authors.initials: CS
authors.lastname: Simpson
authors.forename: David H
authors.initials: DH
authors.lastname: Birnie
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Healey
authors.forename: Vijay
authors.initials: V
authors.lastname: Chauhan
authors.forename: Jean
authors.initials: J
authors.lastname: Champagne
authors.forename: Martin
authors.initials: M
authors.lastname: Gardner
authors.forename: Shubhayan
authors.initials: S
authors.lastname: Sanatani
authors.forename: Raymond
authors.initials: R
authors.lastname: Yee
authors.forename: Allan C
authors.initials: AC
authors.lastname: Skanes
authors.forename: Lorne J
authors.initials: LJ
authors.lastname: Gula
authors.forename: Peter
authors.initials: P
authors.lastname: Leong-Sit
authors.forename: Kamran
authors.initials: K
authors.lastname: Ahmad
authors.forename: Michael H
authors.initials: MH
authors.lastname: Gollob
authors.forename: Michel
authors.initials: M
authors.lastname: Haïssaguerre
authors.forename: George J
authors.initials: GJ
authors.lastname: Klein
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Krahn
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D016757:Death, Sudden, Cardiac; D004562:Electrocardiography; D005260:Female; D006323:Heart Arrest / Q000209:etiology / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012042:Registries; D013318:Stroke Volume; D014693:Ventricular Fibrillation / Q000150:complications / Q000503:physiopathology / Q000628:therapy; D055815:Young Adult