Genetic architecture of long QT syndrome and genotype-specific treatment

Congenital long QT syndrome (LQTS) is the first described and most common inherited arrhythmia in the absence of structural heart disease, which is inherited in a predominantly autosomal dominant manner, characterized by an increased risk of developing polymorphic ventricular tachycardia, syncope and/or seizures, and sudden cardiac death. According to modern ideas about the spectrum of genetic variants that can contribute to the genetic architecture of LQTS, this disease cannot be considered as a monogenic pathology. This is supported by the presence not only of pathogenic or likely pathogenic variants in the canonical LQTS susceptibility genes, but also of common potentially proarrhythmic variants or functional risk alleles and poorly penetrating rare variants. Since LQTS is a genetically and phenotypically heterogeneous disease, timely verification of the diagnosis of LQTS and risk stratification of arrhythmic events, as well as the implementation of a genotype-specific therapeutic strategy, seem relevant.