This review examines the role of spatial electrical heterogeneity within the ventricular myocardium on the function of the heart in health and disease. The cellular basis for transmural dispersion of repolarization (TDR) is reviewed, and the hypothesis that amplification of spatial dispersion of repolarization underlies the development of life-threatening ventricular arrhythmias associated with...

Smiseth OA, Amlie JP. Left ventricular mechanical dispersion by tissue Doppler imaging: a novel approach for identifying high-risk individuals with long QT syndrome. Eur Heart J 2009;30:330–337. 3. Schwartz PJ, Priori SG, Spazzolini C, Moss AJ, Vincent GM, Napolitano C, Denjoy I, Guicheney P, Breithardt G, Keating MT, Towbin JA, Beggs AH, Brink P, Wilde AA, Toivonen L, Zareba W, Robinson JL, Ti...

Dental trauma secondary to a syncopal episode occurs rarely in the pediatric population. Although the majority of these events occurs in patients with a benign medical history, a subset of these cases occur in patients with a genetic predisposition to cardiac arrhythmia. Long QT syndrome, characterized by prolonged cardiac ventricular repolarization, represents one genetic condition in which pa...