Long QT syndrome is the prototypical disorder of ventricular repolarization (VR), and a genotype-phenotype relation is postulated. Furthermore, although increased VR heterogeneity (dispersion) may be important in the arrhythmogenicity in long QT syndrome, this hypothesis has not been evaluated in humans and cannot be tested by conventional electrocardiography. In contrast, vectorcardiography al...

QT dispersion was originally proposed to measure spatial dispersion of ventricular recovery times. Later, it was shown that QT dispersion does not directly reflect the dispersion of recovery times and that it results mainly from variations in the T loop morphology and the error of QT measurement. The reliability of both automatic and manual measurement of QT dispersion is low and significantly ...

AIM It has previously been shown that β-blocker therapy reduces QT dynamics in heart failure patients. The aim of this study was to demonstrate this improvement with the third-generation β-blocker, nebivolol. METHODS A total of 72 heart failure patients with systolic dysfunction were included in the study. Corrected QT (QTc) and QT dispersion (QTcd) were measured manually by two independent o...

It is known that in patients with ischemic heart disease, QT dispersion (QTd) predicts ventricular arrhythmia and sudden cardiac death and that major coronary risk factors such as smoking, diabetes mellitus, hypertension increase QTd. It is not clear whether, in coronary artery disease, QTd increases because of ischemia or co-existence of coronary risk factors. In this study, we aimed to invest...

BACKGROUND Electrophysiological information as well as anatomic information are important for the detection of coronary artery lesions. The aim of this study was to assess the efficacy of resting magnetocardiography (MCG) in stable coronary artery disease (CAD) and cardiac allograft vasculopathy (CAV). METHODS AND RESULTS MCG and coronary angiography were performed within 1 month in 75 patien...

The difference between the maximum and minimum QT interval measured from a 12-lead electrocardiogram was defined as an index of spatial inhomogeneous repolarization of the ventricular myocardium. The causal relationship between QT dispersion and incidence of ventricular arrhythmias has been pointed out in various heart diseases, but until now it was discussed mainly related to sinus rhythm. QT ...