QT dispersion (QTD) on 12-lead ECGs has been proposed as a marker of malignant ventricular tachyarrhythmias, and increased QTD has been reported in long QT syndrome (LQTS). On the other hand, it has been demonstrated that transmural dispersion is associated with ventricular tachyarrhythmias in an experimental model. However, the precise type of QTD or transmural dispersion that contributes most...

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...

Oliveira M.S., Muzzi R.A.L., Muzzi L.A.L., Cherem M. & Mantovani M.M. 2014. QT interval in healthy dogs: which method of correcting the QT interval in dogs is most appropriate for use in small animal clinics? Pesquisa Veterinária Brasileira 34(5):469472. Departamento de Medicina Veterinária, Universidade Federal de Lavras, Cx. Postal 3037, Lavras, MG 37200-000, Brazil. E-mail: [email protected]...

Ideal of Fuzzy Inference System and Manifold Deterioration Using Genetic Algorithm and Particle Swarm Optimization is presented. Hypoglycaemia or low blood glucose often occurs with patients that take insulin therapy for diabetes. Hypoglycaemia is serious and causes unconsciousness, seizures or even death. The proposed system uses ECG signal for the detection of hypoglycemia. To find the presen...

Introduction Determination of the QT interval dispersion by means of a standard ECG at rest has been widely used for cardiovascular risk assessment during the last 15 years as one of the recent explanations for the development of life threatening ventricular arrhythmias. However, little is known about the relation between QT dispersion and the severity of coronary artery atherosclerosis as defi...

The evaluation of every electrocardiogram should also include an effort to interpret the QT interval to assess the risk of malignant arrhythmias and sudden death associated with an aberrant QT interval. The QT interval is measured from the beginning of the QRS complex to the end of the T-wave, and should be corrected for heart rate to enable comparison with reference values. However, the correc...

We examined the relationship between changes in heart rate and the measured QT interval of the electrocardiogram in healthy subjects after exercise and during breath holding, hyperventilation, the dive reflex, the Valsalva maneuver, and the cold-pressor test. The tachycardia of exercise was accompanied by the familiar shortening of the QT interval, but substantial heart rate changes encountered...

1.1 Definition and prevalence Long QT syndrome (LQTS) is a familial condition causing syncope and sudden death through rapid ventricular tachycardia (torsade de pointes), which can deteriorate to ventricular fibrillation, in otherwise fit and healthy young people. Prevalence is approximately 1 in 2,500. 1 Clinical diagnosis is made from a combination of suspicious history, family history and th...

BACKGROUND We set out to identify common genetic determinants of the length of the RR and QT intervals in 2325 individuals from isolated European populations. METHODS AND RESULTS We analyzed the heart rate at rest, measured as the RR interval, and the length of the corrected QT interval for association with 318 237 single-nucleotide polymorphisms. The RR interval was associated with common va...

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...