Long QT syndrome in adults.

Objectives: The aims of this study were: 1) to evaluate risk factors influencing the clinical course of mutation-confirmed adult patients with long QT syndrome (LQTS), 2) to study life-threatening cardiac events as a specific end point in adults, and 3) to examine the protective effect of beta-blocker therapy on cardiac events in adult LQTS patients with known cardiac channel mutations.

Background: The clinical course and risk factors for cardiac events in genotype-confirmed adult patients with LQTS have not been previously investigated.

Methods: The clinical characteristics of 812 mutation-confirmed LQTS patients age 18 years or older were studied with both univariate and multivariate analyses to determine the genotype-phenotype factors that influence the clinical course of adult patients with this disorder.

Risk of aborted cardiac arrest or sudden cardiac death during adolescence in the long-QT syndrome.

Context: Analysis of predictors of cardiac events in hereditary long-QT syndrome (LQTS) has primarily considered syncope as the predominant end point. Risk factors specific for aborted cardiac arrest and sudden cardiac death have not been investigated.

Objective: To identify risk factors associated with aborted cardiac arrest and sudden cardiac death during adolescence in patients with clinically suspected LQTS.