title: Patterns of QT dispersion in athletic and hypertensive left ventricular hypertrophy.
abstract: OBJECTIVE
  The objective of this article is to assess whether left ventricular hypertrophy (LVH) due to physical training or of hypertensive patients shows similarities in QT length and QT dispersion.
  
  
  METHODS
  A total of 51 subjects were studied: 17 essential hypertensive patients (27.7 +/- 5.6 years), 17 athletes involved in agonistic activity (canoeing) (24.8 +/- 6.1 years), and 17 normotensive healthy subjects as control group (24.8 +/- 3.6 years). The testing protocol consisted of (1) clinic BP measurement, (2) echocardiography, (3) 12-lead electrocardiographic examination (QT max, QTc max, QT min, QTc min, DeltaQT, DeltaQTc).
  
  
  RESULTS
  There were no significant differences between the body surface area, height, and age of the three groups. Clinic blood pressure was higher in hypertensives (146.5 +/- 45.2/93.5 +/- 4.9 mmHg) versus athletes (120.9 +/- 10.8/77.1 +/- 6.0 mmHg) and controls (123.5 +/- 4.8/78.8 +/- 2.9 mmHg) by definition. Indexed left ventricular mass (LVM/BSA) was significantly greater in both athletes (148.9 +/- 21.1 g/m2) and hypertensives (117.1 +/- 15.2 g/m2) versus controls (81.1 +/- 14.5 g/m2; P < 0.01), there being no statistical difference among them. LVH (LVMI > 125 g/m2) was observed in all athletes, while the prevalence in hypertensives was 50%. In spite of this large difference in cardiac structure there were no significant differences in QT parameters between athletes and the control group, while hypertensive patients showed a significant increase in QT dispersion versus the two other groups (DeltaQT 82 +/- 2.1, 48 +/- 1.3, 49 +/- 2.3 ms; P < 0.01; DeltaQTc 88 +/- 2.0, 47 +/- 1.4, 54 +/- 2.7; P < 0.01).
  
  
  CONCLUSIONS
  LVH induced by physical training activity is not associated with an increase in QT dispersion, whereas pathological increase in LVM secondary to hypertension is accompanied by an increased QT dispersion.
authors.affiliation: Istituto Auxologico Italiano, Divisione di Cardiologia I, Ospedale S. Luca IRCCS, Milan, Italy. l.lonati@auxologico.it
authors.forename: Laura Maria
authors.initials: LM
authors.lastname: Lonati
authors.forename: Gaia
authors.initials: G
authors.lastname: Magnaghi
authors.forename: Caterina
authors.initials: C
authors.lastname: Bizzi
authors.forename: Gastone
authors.initials: G
authors.lastname: Leonetti
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001795:Blood Pressure Determination; D016009:Chi-Square Distribution; D004452:Echocardiography; D004562:Electrocardiography; D006801:Humans; D006973:Hypertension / Q000503:physiopathology*; D017379:Hypertrophy, Left Ventricular / Q000175:diagnosis / Q000503:physiopathology*; D008297:Male; D013177:Sports / Q000502:physiology*