long-QT syndrome

long-QT syndrome

A genetic disorder in which the interval between the Q and the T waves of the electrocardiogram is usually, but not necessarily, prolonged to 500 msec or more. The condition is due to defects of potassium ion or sodium ion channels in heart muscle and features fast heart rate, heart irregularities, fainting and sometime sudden death. Six different mutations of genes coding for the ion channels have been detected, but in about 50 per cent of cases these mutations do not produce symptoms. Sudden death occurs only in ablout 4 per cent of affected persons.
References in periodicals archive ?
Influence of the genotype on the clinical course of the long-QT syndrome. International long-QT syndrome registry research group.
Crotti et al., "Prevalence of the congenital long-qt syndrome," Circulation, vol.
Long-QT syndrome is a congenital or acquired (drug-induced) disorder of the heart's electrical activity, inducing delayed repolarization that can cause also ventricular arrhythmias and sudden cardiac death4.
Rognum et al., "Prevalence of long-QT syndrome gene variants in sudden infant death syndrome," Circulation, vol.
Compound mutations: a common cause of severe long-QT syndrome. Circulation 2004; 109: 1834-41.
Diagnostic miscues in congenital long-QT syndrome. Circulation.
Spazzolini et al., "Genotype-phenotype correlation in the long-QT syndrome: gene-specific triggers for life-threatening arrhythmias," Circulation, vol.
Chronic Amiodarone Evokes No Torsade de Pointes Arrhythmias Despite QT Lengthening in an Animal Model of Acquired Long-QT Syndrome. Circulation.
Risk factors for aborted cardiac arrest and sudden cardiac death in children with the congenital long-QT syndrome. Circulation 2008;117:2184-91.
Crotti etal., "Prevalence of the congenital long-QT syndrome," Circulation, vol.
Genetic testing for long-QT syndrome: Distinguishing pathogenic mutations from benign variants.
Effects of beta-blocker therapy on ventricular repolarization documented by 24-h electrocardiography in patients with type 1 long-QT syndrome. J Am Coll Cardiol.