Background—Electrocardiographic QT interval prolongation is a risk factor for sudden cardiac death and drug-induced arrhythmia. The clinical correlates and heritability of QT interval duration in blacks have not been well studied despite their higher risk for sudden cardiac death compared with non-Hispanic whites. We sought to investigate potential correlates of the QT interval and estimate its...

The syndrome of long QT interval frequently follows to syncope or a sudden cardiac death on the basis of originated polymorphic ventricular tachycardia of the "torsade de pointes" type. The prolongation of the QT interval in the hereditary form is based on mutation of the genes responsible for the formation of sodium and potassium channels. The authors analyze the occurrence, clinical findings,...

Chronic hepatitis B (CHB) is a chronic inflammatory viral disorder. Several studies have suggested that the interval from the peak to the end of the electrocardiographic T wave (Tp-e) may correspond to the transmural dispersion of repolarisation and that increased Tp-e interval and Tp-e/QT ratio are associated with malignant ventricular arrhythmias. Impaired autonomic function has been describe...

AIMS Women have a longer QT interval and a greater incidence of torsades de pointes than men. It has been suggested that oestrogens may influence the duration of cardiac repolarization. We thus investigated the influence of oestradiol (E2) on ventricular repolarization within the physiological concentration range of this hormone. METHODS AND RESULTS We studied QT interval duration in 21 healt...

Probucol administration of 4 weeks produced torsades de pointes associated with exacerbated QT interval prolongation in a 36-year-old woman with Romano-Ward syndrome. With discontinuance of probucol, the QT interval corrected for rate shortened from 620 msec to 500 msec and ventricular ectopic beats disappeared completely. Although probucol is known to prolong the QT interval, associated ventri...

QT interval of the electrocardiogram (ECG) reflects the duration of the ventricular action potential. It is prolonged usually when there is delayed repolarisation due to diminished outward potassium current during phase 2 and 3 of the action potential. Clinically, it is an important pharmacological effect of a drug. This effect, when exerted in a carefully controlled manner, is the primary phar...

background: the role of methadone in qtc prolongation, torsades de pointes (tdp) arrhythmia and sudden cardiac death has been debated. because of widespread use of methadone in methadone maintenance treatment (mmt) centers, we aimed to study dose-related effects of methadone on qtc prolongation. methods: in a comparative observational study, 90 patients who were under mmt were evaluated. patien...

A right module M over an associative ring with unity is a QTAG-module if every finitely generated submodule of any homomorphic image of M is a direct sum of uniserial modules. In this paper we find a suitable condition under which a special ω-elongation of a summable QTAG-module by a ( ω +k)-projective QTAG-module is also a summable QTAG-module.

BACKGROUND AND PURPOSE Automated measurements of electrocardiographic (ECG) intervals are widely used by clinicians for individual patient diagnosis and by investigators in population studies. We examined whether clinically significant systematic differences exist in ECG intervals measured by current generation digital electrocardiographs from different manufacturers and whether differences, if...

OBJECTIVES QT interval prolongation is associated with increased risk of sudden cardiac death at the population level. As 30-40% of the QT-interval variability is heritable, we tested the association of common LQTS and NOS1AP gene variants with QT interval in a Finnish population-based sample. METHODS We genotyped 12 common LQTS and NOS1AP genetic variants in Health 2000, an epidemiological s...