Congenital mutations in KCNQ1 and KCNE1 (corresponding to LQTS subtypes LQT1 and LQT5, respectively), account for over 50% of inherited LQTS [22], and are associated with arrhythmias triggered by exercise-related increase in heart rate and β-adrenergic stimulation [23]. Here, KCNE1 is linked to long QT syndrome 5.