Article
American Journal of Hypertension (2008) 21 47–53; doi:10.1038/ajh.2007.4
Recent Ventricular Repolarization Markers in Resistant Hypertension: Are They Different from the Traditional QT Interval?
Gil F Salles1, Claudia R.L Cardoso1, Sharon M Leocadio1 and Elizabeth S Muxfeldt1
1Department of Internal Medicine, University Hospital Clementino Fraga Filho, Medical School, Federal University of Rio de Janeiro, Brazil
Correspondence: Gil F. Salles, (gilsalles@hucff.ufrj.br)
Received 15 June 2007; First Decision 12 July 2007; Accepted 28 July 2007.
Abstract
Background
Two electrocardiographic markers of ventricular repolarization abnormalities have been recently proposed: spatial T-wave axis deviation and Tpeak–Tend-interval duration. The aim of this study was to evaluate these markers in patients with resistant hypertension, particularly their relationships with left ventricular mass (LVM) and geometric patterns, in comparison with the more traditional marker, the QTc interval.
Methods
In a cross-sectional study, 810 resistant hypertensive patients were evaluated. Clinical, laboratory, electrocardiographic, 24-h blood pressures and echocardiographic variables were obtained. Maximum Tpeak–Tend-interval duration (Tpemax) was considered prolonged if it was beyond the upper quartile value (120 ms), and the spatial T-wave axis on the frontal plane was considered abnormally deviated if >105° or < 15°. Statistical analysis involved bivariate tests, multivariate logistic regression and analysis of covariance.
Results
Tpemax-interval prolongation, like QTc-interval prolongation, was found to be associated with body mass index, 24-h systolic blood pressure (SBP), indexed LVM, serum potassium, and heart rate. Abnormal T-axis deviation was associated with male gender, presence of coronary heart disease, serum creatinine, 24-h SBP, LVM, and serum potassium. All three repolarization parameters were shown to be associated with increased LVM, after adjustment for possible confounders. However, when included together into the same model, only abnormal T-axis and QTc-interval prolongation remained independently associated with LVM. All three parameters were also increased in patients with concentric hypertrophy geometric pattern.
Conclusions
Both the recently proposed repolarization parameters are associated with increased LVM and hypertrophy in patients with resistant hypertension, but only abnormal T-wave axis deviation appears to have distinct and additive relationships to the more classic marker, the QTc interval. Their prognostic values should be addressed in prospective studies.
American Journal of Hypertension (2008) 21 47–53; doi:10.1038/ajh.2007.4
MORE ARTICLES LIKE THIS
These links to content published by NPG are automatically generated.
RESEARCH
Usefulness of QT-interval parameters for cardiovascular risk stratification in type 2 diabetic patients with arterial hypertensionJournal of Human Hypertension Original Article
Multivariate associates of QT interval parameters in diabetic patients with arterial hypertension: importance of left ventricular mass and geometric patternsJournal of Human Hypertension Original Article
QT Dispersion in Uncomplicated Human ObesityObesity Research Original Article
Biliopancreatic Diversion Reduces QT Interval and Dispersion in Severely Obese Patients *Obesity Original Article
See all 27 matches for Research