title: Long-term outcome associated with early repolarization on electrocardiography.
abstract: BACKGROUND
  Early repolarization, which is characterized by an elevation of the QRS-ST junction (J point) in leads other than V(1) through V(3) on 12-lead electrocardiography, has been associated with vulnerability to ventricular fibrillation, but little is known about the prognostic significance of this pattern in the general population.
  
  
  METHODS
  We assessed the prevalence and prognostic significance of early repolarization on 12-lead electrocardiography in a community-based general population of 10,864 middle-aged subjects (mean [+/-SD] age, 44+/-8 years). The primary end point was death from cardiac causes, and secondary end points were death from any cause and death from arrhythmia during a mean follow-up of 30+/-11 years. Early repolarization was stratified according to the degree of J-point elevation (> or = 0.1 mV or > 0.2 mV) in either inferior or lateral leads.
  
  
  RESULTS
  The early-repolarization pattern of 0.1 mV or more was present in 630 subjects (5.8%): 384 (3.5%) in inferior leads and 262 (2.4%) in lateral leads, with elevations in both leads in 16 subjects (0.1%). J-point elevation of at least 0.1 mV in inferior leads was associated with an increased risk of death from cardiac causes (adjusted relative risk, 1.28; 95% confidence interval [CI], 1.04 to 1.59; P=0.03); 36 subjects (0.3%) with J-point elevation of more than 0.2 mV in inferior leads had a markedly elevated risk of death from cardiac causes (adjusted relative risk, 2.98; 95% CI, 1.85 to 4.92; P<0.001) and from arrhythmia (adjusted relative risk, 2.92; 95% CI, 1.45 to 5.89; P=0.01). Other electrocardiographic risk markers, such as a prolonged QT interval corrected for heart rate (P=0.03) and left ventricular hypertrophy (P=0.004), were weaker predictors of the primary end point.
  
  
  CONCLUSIONS
  An early-repolarization pattern in the inferior leads of a standard electrocardiogram is associated with an increased risk of death from cardiac causes in middle-aged subjects.
authors.affiliation: Institute of Clinical Medicine, Department of Internal Medicine, University of Oulu, Oulu, Finland.
authors.forename: Jani T
authors.initials: JT
authors.lastname: Tikkanen
authors.forename: Olli
authors.initials: O
authors.lastname: Anttonen
authors.forename: M Juhani
authors.initials: MJ
authors.lastname: Junttila
authors.forename: Aapo L
authors.initials: AL
authors.lastname: Aro
authors.forename: Tuomas
authors.initials: T
authors.lastname: Kerola
authors.forename: Harri A
authors.initials: HA
authors.lastname: Rissanen
authors.forename: Antti
authors.initials: A
authors.lastname: Reunanen
authors.forename: Heikki V
authors.initials: HV
authors.lastname: Huikuri
mesh_terms: D000328:Adult; D001145:Arrhythmias, Cardiac / Q000150:complications / Q000453:epidemiology / Q000401:mortality / Q000503:physiopathology*; D016757:Death, Sudden, Cardiac / Q000209:etiology; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011379:Prognosis; D012306:Risk