Long QT intervals in the ECG have long been associated with sudden cardiac death. The congenital long QT syndrome was first described in individuals with structurally normal hearts in 1957.1 Little was known about the significance of a short QT interval. In 1993, after analyzing 6693 consecutive Holter recordings Algra et al concluded that an increased risk of sudden death was present not only ...

Sudden infant death syndrome (SIDS) is a multifactorial disorder in which newborns tragically die in their sleep for no obvious reason and without prior warning. SIDS is defined as “the sudden death of an infant which is unexpected by history, and in which a full postmortem examination fails to demonstrate an adequate cause of death.”1 Although SIDS may occur in more than one child in a family,...

BACKGROUND Recent molecular biological investigations have identified abnormal genes in familial forms of long QT syndrome, but in bradycardia dependent acquired long QT syndrome, no such genetic abnormality has yet been identified. OBJECTIVE To investigate the relation between the responses of QT interval to pacing change and to disopyramide. METHODS This study included 13 patients with br...

The long QT syndrome affects predominantly younger people who demonstrate structurally normal hearts. The underlying defect in the long QT syndrome seems to be genetic mutations in the cardiac ionic channels responsible for generating action potentials. Genetic linkage mapping has identified six genes (designated LQT1-6) associated with the Romano-Ward syndrome; two of these genes (LQT1, LQT5) ...