Rediscovering Clinical Utility of QT Dispersion: A Long-Forgotten Parameter

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.