Electrocardiographic measures of ventricular repolarization

Electrocardiographic measures of ventricular repolarization Brief Review Abstract: Electrocardiographic measures of ventricular repolarization include QT dispersion, T wave width, spatial QRS-T angle and T peak to T end interval. Following parameters have been used as electrocardiographic measures of ventricular repolarization: QT variation between different ECG leads (QT dispersion) T peak to T end interval (Tp-Te) T wave width Spatial angle between QRS and T vectors QT dispersion Difference in QT interval between the surface electrocardiographic leads is known as QT dispersion. QT dispersion can be defined as the difference between the maximum and minimum QT intervals on body surface electrocardiogram.1 QT dispersion is thought to reflect the inhomogeneity of repolarization and hence an indicator of arrhythmia potential. Inhomogenous repolarization of myocardial repolarization can predispose to re-entrant circuits leading to life threatening ventricular arrhythmias. Reduction of QT dispersion is has also been considered as the mechanism of beneficial effect of a class III antiarrhythmic drug.2  The validity of QT dispersion as a true indicator of dispersion of ventricular repolarization has been also questioned. It has been mentioned that QT dispersion is just a measure of T loop variation and error in QT measurement.3 T peak to T end interval (Tp-Te) Interval from the peak of T wave to the end of the T wave (Tp-Te) has been taken as an index of global dispersion of re...
Source: Cardiophile MD - Category: Cardiology Authors: Tags: ECG / Electrophysiology Source Type: blogs