Abstract
Clinical and experimental electrophysiological studies have shown the importance of inhomogeneous myocardial repolarization in ventricular arrhythmias' genesis. Increased dispersion of repolarisation provides a substrate for ventricular arrhythmias by generating functional unidirectional block areas, thereby predisposing to reentry. QT dispersion, defined as the difference between the longest and the shortest QT interval on the surface ECG, is a validated measure of repolarisation dispersion. QT dispersion predicts sudden death and ventricular arrhythmias in patients with chronic heart failure from coronary heart disease and various cardiac diseases
Highlights
The concept of QT dispersion was first introduced by Day et al in 1990
QT dispersion represents an indirect measurement of ventricular repolarization heterogeneity, with T wave interval is the primary determinant of QT interval duration
T wave offset determines the end of the QT interval and, QT dispersion
Summary
The concept of QT dispersion was first introduced by Day et al in 1990. It was proposed as the dispersion of various ventricular recovery times. QT dispersion represents an indirect measurement of ventricular repolarization heterogeneity, with T wave interval is the primary determinant of QT interval duration. Ventricular repolarization abnormality may disrupt the dynamicity of T wave loop formation and projections toward ECG, forming variable QT intervals in different leads [1]. As a consequence of both different actual lengths and different measurable duration of QT intervals, QT dispersion, if the heart vector becomes perpendicular to one of the leads' axis, two imaginary T waves of the same magnitude have different offsets (dashed lines).
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
