STUDY OBJECTIVE To evaluate the effects of methadone on QT-interval dispersion. DESIGN Single-center, prospective, cohort study. SETTING Methadone maintenance treatment facility. PATIENTS One hundred eighteen patients who were newly admitted to the facility. Intervention. Twelve-lead electrocardiograms (ECGs) were performed in patients at both baseline and 6 months after the start of meth...

Homogeneity of recovery time protects against arrhythmias whereas dispersion of recovery time is arrhythmogenic. A single surface electrocardiographic QT interval gives no information on recovery time dispersion but the difference between the maximum and minimum body surface QT interval may be relevant. This hypothesis was tested by measuring the dispersion of the corrected QT interval (QTc) in...

BACKGROUND Syncope is defined as transient loss of consciousness and muscle tone, usually of short duration. Noncardiac causes of syncope are classified as orthostatic intolerance syndromes (OIS). QT and QTc (corrected QT) dispersions are the measurements of myocardial instability and show predisposition to arrhythmias. In this study; clinical findings, QT and QTc dispersions of the patients wh...

Background Coronary artery ectasia (CAE) is defined as a diffuse dilatation of the diameter of the ectatic segment of the coronary artery, 1.5 times greater than that of the adjacent segment. The Tp-Te interval, P-wave and QTc dispersions are relatively new electrocardiographic markers associated with an increased risk of developing arrhythmias. Despite CAE increasing in prevalence in recent ye...

Background: Cigarette smoking has several known detrimental effect on cardiovascular system.  QT dispersion (QTd) is among the important predictors of cardiac death. Objective:  To assess the acute effect of smoking of a single standard cigarette on QT and QTc (corrected QT) dispersion, hence on the risk of ventricular arrhythmias in healthy smokers and non-smokers. Methods: 111 healthy men wit...

Angiotensin type 1 receptor antagonists have direct effects on the autonomic nervous system and myocardium. Because of this, we hypothesized that irbesartan would reduce QT dispersion to a greater degree than amlodipine, a highly selective vasodilator. To test this, we gathered electrocardiographic (ECG) data from a multinational, multicenter, randomized, double-blind parallel group study that ...

BACKGROUND: Considering that determining the effect of both contrast dye injection and balloon inflation on electrophysiological parameters would help us to predict the ischemic event during PTCA, the aim of this study was to determine the effects of these factors on QTc and QTc dispersion during PTCA in Isfahan. METHODS: In this cross-sectional study, consecutive patients undergoing elective P...

The relationship between the location and size of an infarction and QT dispersion was investigated in 84 Japanese patients with chronic myocardial infarction (54 with anteroseptal infarction and 30 with inferior infarction). The control group consisted of 23 subjects without ischemic heart disease (13 normal subjects and 10 hypertensive patients). Corrected QT dispersion (maximum corrected QT i...

This study was planned to clarify the mechanism(s) by which hemodialysis increases the QTc dispersion, a marker of risk of ventricular arrhythmias. To this aim, 10 uremic patients, without any relevant heart diseases, underwent two different types of hemodialysis schedules. In the first, 1 h of isolated high rate ultrafiltration preceded the standard diffusive procedure. In the second, during t...

BACKGROUND Considering that determining the effect of both contrast dye injection and balloon inflation on electrophysiological parameters would help us to predict the ischemic event during PTCA, the aim of this study was to determine the effects of these factors on QTc and QTc dispersion during PTCA in Isfahan. METHODS In this cross-sectional study, consecutive patients undergoing elective P...