Inherited Long QT Syndromes: Be Mindful of the Potassium Level

Clinical Perspective. Molecular genetics of inherited long QT syndromes

Unravelling the molecular cause of QT prolongation is one of the most exciting contributions of molecular biology to clinical cardiology in the last decade. Not only have mutations in four different genes been described, at least two additional chromosomal loci have been identified harbouring genes with an as yet unknown DNA sequence and protein function. Simultaneously cellular electrophysiolo...

Effects of mutations and genetic overlap in inherited long-QT and Brugada arrhythmia syndromes.

Long-QT syndrome (LQTS) is an inherited cardiac disease that is characterised by prolongation of the QT interval on the electrocardiogram and is associated with syncopal episodes, dangerous ventricular arrhythmias of the torsades de pointes type, and a high risk of sudden death on a substrate of a structurally normal heart. Today we know that LQTS is an inherited autosomal dominant arrhythmogen...

Diagnostic Evaluation of Congenital Long Qt Syndromes

Short and long QT syndromes: does QT length really matter?

The short and long QT syndromes are inherited diseases associated with an increased risk for life-threatening arrhythmias. The first case of long QT syndrome (LQTS) was reported more than 150 years ago, and the study of this disease led to crucial advancement of our understanding of channelopathies and associated ventricular arrhythmias. Ten years ago, Gussak et al. reported four cases of idiop...

Congenital long and short QT syndromes.

Congenital long and short QT syndromes are familial arrhythmias characterized by derangement of repolarization and a high risk of sudden cardiac death due to ventricular tachyarrhythmias. With growing understanding of these syndromes in both the medical and lay communities, diagnostic and therapeutic difficulties are increasingly faced by health care providers. Modern genomics has determined th...