CNVs involving single or multiple exons of the major channelopathy genes, KCNQ1, KCNH2, SCN5A, and RYR2, uncommonly serve as the pathogenic basis of dominantly inherited arrhythmia syndromes such as long QT syndrome, Brugada syndrome, and CPVT (3, 8, 9, 11, 17–19). Here, KCNH2 is linked to catecholaminergic polymorphic ventricular tachycardia.