Clinical and genetic profile of the LQTS family. (A) Genotype of SCN5A and KCNH2 of each family member. SCN5A_1473F/F is referred to as WT SCN5A in the text. See text (Results section hERG channel activity in iPSC-CMs) for definitions of KCNH2 variants. (B, top) Surface electrocardiography lead II recorded from the LQT-3 proband before this study. QTc, QT interval corrected for heart rate. (bottom) Example of ICD detection and termination of ventricular tachyarrhythmia in proband.