Congenital long QT syndrome type 3

Long QT syndrome type 3 (LQT3) is caused by mutations of the SCN5A gene encoding the α-subunit of the human cardiac sodium channel. Specific ST-T wave patterns, triggers, and risk for cardiac events are associated with this LQTS variant. Bench studies have gathered enough knowledge to devise gene-specific therapies to specifically counteract the effects of the mutations. In this article, the authors delineate the LQT3 pathophysiology and epidemiology. They also discuss the clinical management with a focus on the appropriate use of gene-specific therapy.