T Wave Amplitude Correction of QT Interval Variability for Improved Repolarization Lability Measurement

T Wave Amplitude Correction of QT Interval Variability for Improved Repolarization Lability Measurement

OBJECTIVES The inverse relationship between QT interval variability (QTV) and T wave amplitude potentially confounds QT variability assessment. We quantified the influence of the T wave amplitude on QTV in a comprehensive dataset and devised a correction formula. METHODS Three ECG datasets of healthy subjects were analyzed to model the relationship between T wave amplitude and QTV. To derive ...

Beat-to-beat QT interval variability and T-wave amplitude in patients with myocardial infarction.

The purpose of this study was to investigate the effects of T-wave amplitude and ECG lead on beat-to-beat QT interval variability (QTV) in patients with myocardial infarction (MI) compared to healthy subjects. Standard resting 12-lead ECGs of 79 MI patients and 69 healthy subjects were investigated. Beat-to-beat QT intervals were measured separately for each lead using a template matching algor...

Relation between beat-to-beat QT interval variability and T-wave amplitude in healthy subjects.

OBJECTIVES Elevated beat-to-beat QT interval variability (QTV) has been associated with increased cardiovascular morbidity and mortality.The aim of this study was to investigate interlead differences in beat-to-beat QTV of 12-lead ECG and its relationship with the T wave amplitude. METHODS Short-term 12-lead ECGs of 72 healthy subjects (17 f, 38 ± 14 years; 55 m, 39 ± 13 years) were studied. ...

QT Interval and QT Variability

Measurement and regulation of cardiac ventricular repolarization: from the QT interval to repolarization morphology

Ventricular repolarization (VR) is a crucial step in cardiac electrical activity because it corresponds to a recovery period setting the stage for the next heart contraction. Small perturbations of the VR process can predispose an individual to lethal arrhythmias. In this review, I aim to provide an overview of the methods developed to analyse static and dynamic aspects of the VR process when r...