The frontal plane QRS-T angle may affect our perspective on prehypertension: A prospective study.

Backround: The frontal plane QRS-T [f(QRS-T)] angle is an easy marker of myocardial repolarization and was associated with adverse cardiovascular outcomes like prehypertension (PHT). This study was aimed to investigate to evaluate the f(QRS-T) angle in patients with PHT.

Methods: We measured f(QRS-T) angle of 70 subjects with PHT, 109 patients with hypertension (HT), and 102 normotensive healthy volunteers. The f(QRS-T) angle was calculated from 12-lead electrocardiography.

Results: The f(QRS-T) angle was significantly higher in the HT and PHT groups as compared to the control group, but there was no significant difference in the f(QRS-T) angle between the HT and PHT groups. The f(QRS-T) angle was significantly and positively correlated with age, systolic blood pressure (BP) in 24 hours, average BP in 24 hours, pulse pressure in 24 hours, hemoglobin, QT dispersion, TpE distance while was negatively correlated with left ventricular ejection fraction. In multivariable analysis, we showed that systolic BP, average BP in 24 hours, pulse pressure in 24 hours, hemoglobin, QT dispersion, Tpe distance were independent predictors of higher f(QRS-T) angle.

Conclusions: The f(QRS-T) angle, a noninvasive measurement analyzing the dysfunction in cardiac conduction system, was increased in subjects with PHT as compared to normotensives, and the subjects with PHT had f(QRS-T) angle as higher as patients with HT did. Our findings are supportive for the hypothesis that disturbances in ventricular repolarization is present in an early stage of essential hypertension.