The effect of varenicline on Tp-e interval, Tp-e/QT ratio and Tp-e/QTc ratio in healthy smokers and nonsmokers

Abstract

Background: Varenicline could affect the T wave and QT interval. The interval from the peak to the end of the electrocardiographic (ECG) T wave (Tp-e) may correspond to the transmural dispersion of repolarization, and increased Tp-e interval and Tp-e/QT ratio are associated with malignant ventricular arrhythmias. In this study, we assessed the effects of varenicline on Tp-e interval, Tp-e/QT ratio and Tp-e/QTc ratio. Methods: Thirty healthy volunteers (15 healthy non-smokers [NS] and 15 healthy smokers [S]) were included in the randomized, double-blind, placebo-controlled, crossover study. Varenicline (2 mg single dose) or placebo was administered in two different testing sessions (5 days after the first period, performed the second period). Tp-e interval, Tp-e/QT ratio and Tp-e/QTc

Acute effect of cigarette smoking on frontal planar QRS-T angle in apparently healthy subjects with habitual smoking

“…Although there are relatively more studies reporting significant increase in various parameters of ventricular repolarization such as QT interval, QTc interval, Tp-e interval, Tp-e/QT and Tp-e/QTc ratios, QT-dispersion (QTd) and corrected QT-dispersion (QTcd) between long-term smokers and non-smokers [25][26][27], studies on acute effect of cigarette smoking on different ECG parameters are very scanty and focus only on such parameters of ventricular repolarization as QTdispersion (QTd) and corrected QT-dispersion (QTcd) with conflicting results. Akbarzadeh et al [5] and Khosropanah et al [28] reported an escalation in QTd and QTcd following acute exposure to cigarette smoke, whereas another study by Karakaya et al [24] did not reveal a significant difference either in QTd and QTcd or in QT interval.…”

Tp‐e Interval, Tp‐e/QTc Ratio, and Fragmented QRS Are Correlated with the Severity of Liver Cirrhosis

“…Increased dispersion of repolarization showing heterogeneity of repolarization is a sign for lethal ventricular arrhythmias . QT/QTc interval and T wave analyzes are commonly used for ventricular repolarization assessment, and uneven distribution of sympathetic nervous system activity on heart causes prolonged QT interval . In cirrhotic cardiomyopathy high levels of circulating catecholamines, due to enhanced activation of the sympathetic nervous system may lead QT prolongation.…”