KCNH2 and Prolonged QT interval: Within this family, all three male carriers of the <i>KCNH2</i> variant carriers exhibited the Long QT syndrome phenotype: one experienced sudden death during sleep, another received an implantable cardioverter defibrillator (ICD), and a younger man displayed a prolonged QTc interval without any instances of syncope or malignant arrhythmia to date.