Electrophysiological mechanisms of long and short QT syndromes. (March 2017)

• Record Type: Journal Article
• Authors: Tse, Gary; Chan, Yin Wah Fiona; Keung, Wendy; Yan, Bryan P
• Is Part Of: IJC heart & vasculature. Volume 14(2017)
• Page Start: 8
• Page End: 13
• Publication Date: 2017-03
• Subjects: Cardiac arrhythmia -- Repolarization -- Long QT syndrome -- Short QT syndrome -- Wavelength; Cardiovascular system -- Diseases -- Periodicals; Cardiovascular system -- Pathophysiology -- Periodicals; 616.1005
• DOI: 10.1016/j.ijcha.2016.11.006
• Languages: English
• ISSNs: 2352-9067

Abstract

Abstract: The QT interval on the human electrocardiogram is normally in the order of 450 ms, and reflects the summated durations of action potential (AP) depolarization and repolarization of ventricular myocytes. Both prolongation and shortening in the QT interval have been associated with ventricular tachy-arrhythmias, which predispose affected individuals to sudden cardiac death. In this article, the molecular determinants of the AP duration and the causes of long and short QT syndromes (LQTS and SQTS) are explored. This is followed by a review of the recent advances on their arrhythmogenic mechanisms involving reentry and/or triggered activity based on experiments conducted in mouse models. Established and novel clinical risk markers based on the QT interval for the prediction of arrhythmic risk and cardiovascular mortality are presented here. It is concluded by a discussion on strategies for the future rational design of anti-arrhythmic agents.