Management of long QT syndrome.

Congenital long QT syndrome (LQTS) is a genetic disorder characterized by prolongation of the QT interval on the electrocardiogram and by life-threatening cardiac arrhythmias, occurring especially during conditions of increased sympathetic activity. Existing therapies are very effective, but mortality is high among untreated, symptomatic individuals. The identification of several of the genes responsible for LQTS and the realization that they all encode cardiac ion-channels has represented a landmark finding. This advance has fostered novel genotype-phenotype studies that are providing unique insight into how close the relationship can be between molecular biology and clinical cardiology. LQTS represents a paradigm for sudden cardiac death. Indeed, the growing knowledge developed for LQTS is likely to provide the key to understanding the genetic propensity to sudden death in patients with more-common cardiovascular diseases. The data presented here illustrate how the treatment of LQTS is rapidly evolving toward a highly individually tailored approach on the basis of patient-specific genetic information.