Terrenoire et al. (2013) further demonstrated the possibility to use hiPSCs to develop personalised treatment regimens using an hiPSC line derived from an LQT3 patient with a de novo mutation (F1473C) in SCN5A and a polymorphism (K891T) in KCNH2. An implantable cardioverter defibrillator (ICD; Box 1) and high doses of the Na+-channel blocker mexiletine and propranolol helped reduce the numbers of arrhythmias experienced by the patient; however, multiple episodes were still detected daily. This evidence concerns the gene SCN5A and long QT syndrome 3.