The relation between QT interval and T-wave variables in hypertensive patients

Abstract

Background:The standard 12-lead ECG (electrocardiogram) continues to be the most frequently recorded noninvasive test in medicine. A prolonged ECG QT interval and Tpeak-Tend (Tpe) interval are predictors of ventricular arrhythmia and sudden cardiac death.Aim:The aim of this study is to analyze the relation between QT interval and T-wave variables in hypertensive patients, with and without left ventricular hypertrophy (LVH).Materials and Methods:Fifty-nine consecutive patients with grade 2 essential hypertension were included in the study. They underwent standard 12-lead ECG, and QT intervals: QTmax (the maximal duration of the QT interval in the 12 ECG leads), QTc (heart rate corrected QTmax), QTm (mean QT interval), QTII (the QT interval in lead DII), QTcII (heart rate corrected QTII), and QTd (QT dispersion); and T-wave variables: T0e (T wave duration), T0em (mean T0e), Tpe, Tpem (mean Tpem), Ta (T wave amplitude), and Tam (mean Ta) were manually assessed. LVH was diagnosed using both echocardiography and the ECG criteria.Results:QTc was prolonged in 41 patients (69%). Multiple regression analysis revealed a significant association between QT intervals and T-wave variables: QTmax and Tpe (P = 0.015), QTd and Tpe (P = 0.022) and Ta (P = 0.004), and Tpe with QTd and T0e (P < 0.05). A moderate but significant correlation was found between Tpe and QTmax, Tpe and QTII, and Ta and QTd. A prolonged QTc was more prevalent in hypertensive patients with LVH (85%), compared to hypertensive patients without LVH (50%). QTm, QTd, QTII, Tpe, Tpem were significantly elevated (P < 0.05) in patients with LVH.Conclusions:Hypertension is associated with an increased prevalence of prolonged QT intervals. QT intervals and T-wave variables are closely connected in hypertensive patients. QTm, T0em, Tpem, and Tam, do not provide significant additional information compared to QTmax, T0e, Tpe, and Ta. Left ventricular hypertrophy is associated with prolonged QT interval and Tpeak-Tend interval in hypertensive patients.

Repolarização ventricular em pacientes diabéticos: caracterização e implicações clínicas

“…The Tpeak-Tend interval was considered prolonged when greater than 100 ms, and the Tpeak-Tend dispersion was considered prolonged when higher than 20 ms, as suggested by other studies 11,12 .…”

Tp-e/QT ratio and QT dispersion with respect to blood pressure dipping pattern in prehypertension

“…Myocardial repolarization has been evaluated in hypertensive patients in various studies, which highlighted that hypertension is associated with prolonged QT intervals and QT dispersion (QTd) [8,9]. Although data on myocardial repolarization in prehypertension are very limited, QT intervals and dispersion were reported to be prolonged in a prehypertensive state independent of left ventricular mass (LVM) [10].…”

Comparative assessment of effects of calcium channel antagonists, amlodipine, and cilnidipine, on QT interval in hypertensive patients - An observational study

“…Mozos and Serban concluded that hypertension and LVH are associated with an increased prevalence of prolonged QT intervals. [8] Kang also observed that "although hypertrophy can normalize wall tension, it is a risk factor for QT-prolongation and cardiac sudden death." [9] Klimas et al stated that "progressive increase in duration of QT interval associated with the development of cardiac hypertrophy [4][5][6][7] of QTc.…”