title: Predictive value of electrocardiographic QT interval and T-wave morphology parameters for all-cause and cardiovascular mortality in a general population sample.
abstract: BACKGROUND
  The predictive value of ECG QT interval for mortality in the general population has been weak. Only a few population studies on the predictive value of ECG T-wave morphology parameters for mortality have been reported.
  
  
  OBJECTIVE
  The purpose of this study was to examine the predictive value of ECG QT interval and T-wave morphology parameters for all-cause and cardiovascular mortality in the general population.
  
  
  METHODS
  The prognostic values of ECG QT interval and four T-wave morphology parameters (principal component analysis ratio, T-wave morphology dispersion, total cosine R-to-T, T-wave residuum) were assessed in 5,917 adults (45% men; age 52 +/- 14 years) participating in the Finnish population-based Health 2000 Study.
  
  
  RESULTS
  After a mean follow-up of 5.9 +/- 0.8 years, 335 deaths had occurred, including 131 cardiovascular deaths. QT interval and, with a few exceptions, all T-wave morphology parameters were significant univariate mortality predictors. In men, in Cox multivariate analyses, principal component analysis ratio and T-wave morphology dispersion remained as independent predictors of all-cause and cardiovascular mortality, with the above-median T-wave morphology dispersion group showing the highest risk of cardiovascular death (hazard ratio [HR] 4.4, 95% confidence interval [CI] 2.1-9.4). In women, independent mortality predictors were total cosine R-to-T (cardiovascular mortality) and T-wave residuum (all-cause and cardiovascular mortality), with the above-median T-wave residuum group showing the highest risk of cardiovascular death (HR 2.2, 95% CI 1.1-4.2).
  
  
  CONCLUSIONS
  In the general population, T-wave morphology parameters, but not heart rate-corrected QT interval, provide independent prognostic information on mortality. The prognostic value of T-wave morphology parameters is specifically related to cardiovascular mortality and seems to be gender specific.
authors.affiliation: Department of Cardiology, Helsinki University Central Hospital, Helsinki, Finland. porthan@mappi.helsinki.fi
authors.forename: Kimmo
authors.initials: K
authors.lastname: Porthan
authors.forename: Matti
authors.initials: M
authors.lastname: Viitasalo
authors.forename: Antti
authors.initials: A
authors.lastname: Jula
authors.forename: Antti
authors.initials: A
authors.lastname: Reunanen
authors.forename: Janne
authors.initials: J
authors.lastname: Rapola
authors.forename: Heikki
authors.initials: H
authors.lastname: Väänänen
authors.forename: Markku S
authors.initials: MS
authors.lastname: Nieminen
authors.forename: Lauri
authors.initials: L
authors.lastname: Toivonen
authors.forename: Veikko
authors.initials: V
authors.lastname: Salomaa
authors.forename: Lasse
authors.initials: L
authors.lastname: Oikarinen
mesh_terms: D002318:Cardiovascular Diseases / Q000175:diagnosis / Q000401:mortality* / Q000503:physiopathology; D016001:Confidence Intervals; D004562:Electrocardiography / Q000295:instrumentation*; D005260:Female; D005387:Finland / Q000453:epidemiology; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008133:Long QT Syndrome / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D011795:Surveys and Questionnaires