Dynamics of QT Interval in a Patient With Long QT Syndrome and a Normal QT Interval

[The long QT interval syndrome].

The syndrome of long QT interval frequently follows to syncope or a sudden cardiac death on the basis of originated polymorphic ventricular tachycardia of the "torsade de pointes" type. The prolongation of the QT interval in the hereditary form is based on mutation of the genes responsible for the formation of sodium and potassium channels. The authors analyze the occurrence, clinical findings,...

QT Interval and QT Variability

QT interval is linked to 2 long-QT syndrome loci in normal subjects.

BACKGROUND The rate-corrected QT interval (QTc) is heritable, and the discovery of quantitative trait loci that influence the QTc would be an important step in identifying the genes responsible for life-threatening arrhythmias in the general population. We studied 66 pairs of unselected normal dizygotic (DZ) twin subjects and their parents in a sib-pair analysis. We tested for linkage of gene l...

Abnormal repolarization dynamics revealed in exercise test in long QT syndrome mutation carriers with normal resting QT interval.

AIMS The identification of affected family members with long QT syndrome (LQTS) is often difficult due to their normal-or only marginally lengthened-QT interval duration. We examined whether physical exercise test could increase the ability to detect the mutation carrier status in phenotypically normal LQTS family members. METHODS AND RESULTS Sixty-six subjects were included: 15 were carriers...

Catheter ablation of ventricular fibrillation storm in a long QT syndrome genotype carrier with normal QT interval.

Patients with long QT syndrome can sometimes present with a ventricular fibrillation (VF) storm. Catheter ablation of culprit premature ventricular complexes responsible for the triggering of the VF episodes may be required in rare cases of electrical storm that do not respond to conventional measures, and this can be life-saving. We describe a case of emergency catheter ablation in a young wom...