OBJECTIVE To relate QT parameters to infarct size and inducibility during electrophysiological studies. DESIGN Analysis of a prospective register. SETTING University hospital. PATIENTS 64 patients with coronary artery disease and documented life threatening ventricular arrhythmias. INTERVENTIONS Measurements of QT-max, QTc-max, and QT dispersion (QT-d) on a simultaneous 12 lead ECG (50 ...

OBJECTIVE To investigate the role of the autonomic nervous system in determining QT interval and dispersion. PATIENTS AND METHODS 32 patients with chronic primary (idiopathic) autonomic failure (19 men, mean age 60 years) and 21 normal controls (11 men, mean age 59) without symptoms of ischaemic heart disease were studied retrospectively. Autonomic failure was diagnosed by a combination of sy...

Prolonged heart-rate adjusted QT intervals on the electrocardiogram (ECG) are associated with an increased risk for coronary heart disease and sudden death. However, the diagnosis of the prolonged QT interval is hampered by lack of standards. We studied variations in the prevalence of prolonged QT, based on different common definitions, in a large nonhospitalized population, and compared our re...

RATIONALE Recent literature emphasizes the utility of QT variability to study ventricular electrophysiologic function. In this investigation, we sought to test the hypothesis that beat-to-beat fluctuations in QT intervals are mediated by sympathetic activity in normal subjects using postural challenge and isoproterenol infusions. SUBJECTS AND METHODS We obtained ECG in the supine and standing...

We read with great interest the article by Bestas et al1 entitled “The effect of adrenaline on desflurane-induced prolonged QTc interval: a randomized double-blind trial”, which is published in the current issue of European Review for Medical and Pharmacological Sciences. The Authors1 investigated the effect of adrenaline on desflurane-induced prolonged corrected QT (QTc) interval. They mention...

Suggestions were made that increased myocardial sympathetic activity is reflected by elevated QT variability (dynamic changes in QT interval duration). However, the relationship between QT variability and the amount of norepinephrine released from the cardiac sympathetic terminals is unknown. We thus attempted to assess this relationship. The study was performed in 17 subjects (12 with major de...

P rolongation of the QT interval is a serious electrocardiogram finding because of its association with torsades de pointes and sudden cardiac death. Both congenital and acquired factors can lead to abnormal lengthening of the QT interval. Six types of congenital long QT syndrome (LQT1– LQT6) have been described, each involving mutations in genes encoding potassium or sodium transmembrane chann...

BACKGROUND AND PURPOSE Drug-induced prolongation of the QT interval can lead to torsade de pointes, a life-threatening ventricular arrhythmia. Finding appropriate assays from among the plethora of options available to predict reliably this serious adverse effect in humans remains a challenging issue for the discovery and development of drugs. The purpose of the present study was to develop and ...

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 ...