BACKGROUND Assessment of repolarization duration is often recommended to avoid administration of QT-prolonging drugs in patients with prolonged QTc interval, a frequent situation in the postoperative period. Bazett QT correction inappropriately increases QTc when heart rate is increased, and the use of the Fridericia formula may avoid a falsely prolonged QTc interval. The authors assessed autom...

ramadan fasting is one of the most important religious duties of muslims, that its effect on the heart has not been determined yet. our objective was to evaluate the effect of ramadan fasting on ventricular repolarization as assessed by qt interval, corrected qt interval, qt dispersion or corrected qt dispersion. sixthy healthy subjects aged 20 to 35 years were dispersion included in this study...

BACKGROUND/AIMS Although transient changes in the electrocardiogram (ECG) of patients with stress-induced cardiomyopathy (SCMP) are common, there are little data about ECG changes in patients with SCMP and the clinical implications of these variations. METHODS We investigated a total of 128 patients (age, 63.2 ± 15.4 years; female, 60.9%) diagnosed with SCMP. We compared the ECGs taken after ...

Background HAART has improved survival of HIV patients. Its contribution to the development of new cardiovascular abnormalities has generated much interest. This study aimed at determining the prevalence of QTc prolongation among HIV patients and determining the influence if any of the use of HAART on the QTc and on the risk of having QTc prolongation. Materials and Methods One hundred and fi...

The measure of delayed ventricular repolarization most frequently used clinically is the ability of the new chemical entity to prolong the QTc interval on surface electrocardiogram. Intramyocardial dispersion of repolarization appears to play a more important role both in electrical stability of the ventricles and in arrhythmogenesis. The potential importance of myocardial dispersion of refract...

BACKGROUND Prolongation of the corrected QT (QTc) interval is a key issue for patients who receive psychotropic medications. Such patients may have baseline clinical risk factors for QTc prolongation, and many psychotropic medications may further prolong this interval. This has great clinical relevance, as QTc prolongation is linked with dangerous arrhythmias, especially torsades de pointes (Td...

results the mean qtc at baseline (pre-methadone) was 426 ± 34 msec and after being on methadone for an average of 8.72 ± 4.50 years was significantly higher at 450 ± 35 msec. no significant relationships were found between qtc prolongation and risk factors except for calcium. the methadone dosage was significantly higher in veterans with a qtc change above the mean change of ≥ 24 msec (88.48 ± ...

BACKGROUND HD has been reported to determine an increase in QTc interval and QTc dispersion (QT(max)-QT(min))-risk factors that predispose to severe ventricular arrhythmias and sudden death. However, most studies have included end-stage renal disease (ESRD) patients with significant heart pathology. We therefore aimed to study the impact of a single HD session in subjects without manifest cardi...

BACKGROUND In a recent cohort study, prolongation of the corrected QT interval (QTc) was associated with an independent increased risk of sudden cardiac death (SCD). We evaluated determinants of prolonged QTc and the relationship of prolonged QTc to SCD risk among patients with coronary artery disease in the general population. METHODS AND RESULTS A case-control design was used. Cases were SC...

In concentration-QTc modeling, oscillatory functions have been used to characterize biological rhythms in QTc profiles. Fitting such functions is not always feasible because it requires sufficient electrocardiograph sampling. In this study, drug concentration and QTc data were simulated using a published biological QTc model (oscillatory functions). Then, linear mixed-effect models and the biol...