title: [Temporal QT dispersion in patients with systemic blood hypertension].
abstract: OBJECTIVE
  To evaluate QT dispersion in hypertensive patients, with and without left ventricular hypertrophy, and compare with normal persons.
  
  
  METHODS
  Thirty eight patients (21 male and 17 female, age 55 +/- 15 years) underwent echocardiography and simultaneous 12 lead, vertically aligned, electrocardiogram at 50 mm/s speed. No patient was on antiarrhythmic therapy. There were 19 non-hypertensive patients that constituted the control group (G-I). Group II was constituted by the other 19 patients, who were hypertensives. This group was further divided in group II-A (9 patients without left ventricular hypertrophy) and group II-B (10 patients with left ventricular hypertrophy). QT dispersion was obtained by the difference between the longest and the shortest QT registered.
  
  
  RESULTS
  QT dispersion was significantly increased on hypertensive patients, both with and without left ventricular hypertrophy, when compared to controls (G-I 31 +/- 9 ms, G-II 52 +/- 15 ms. P < 0.0001; G-IIa 46 +/- 10 ms and G-IIb 56 +/- 18 ms X G-I, p < 0.0005). In hypertensive patients, there was no statistically significant difference between group II-A and group II-B.
  
  
  CONCLUSIONS
  We conclude that QT dispersion is significantly increased on hypertensive patients when compared to non-hypertensive individuals and that such increase, occurs before left ventricular hypertrophy develops. These findings suggest that, in hypertensive patients, electrical changes in left ventricular myocardium can precede structural and morphological abnormalities. Such findings offer new insights into the mechanisms related to enhanced mortality among hypertensive patients.
authors.affiliation: Serviço de Cardiologia do Hospital Aliança, Salvador.
authors.forename: F
authors.initials: F
authors.lastname: Vilas-Boas
authors.forename: A A
authors.initials: AA
authors.lastname: Lima
authors.forename: J
authors.initials: J
authors.lastname: Torreão
authors.forename: G S
authors.initials: GS
authors.lastname: Feitosa
mesh_terms: D004562:Electrocardiography; D005260:Female; D006339:Heart Rate; D006801:Humans; D006973:Hypertension / Q000503:physiopathology*; D017379:Hypertrophy, Left Ventricular / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged
vernacular_title: Dispersão temporal do QT em pacientes com hipertensão arterial sistêmica.