CALM2 and catecholaminergic polymorphic ventricular tachycardia: The CPVT-associated CaM mutations, N54I, N98S, and A103V, all showed an increased level of RyR2 opening, that is, decreased inhibition by CaM (Hwang et al., 2014; Søndergaard et al., 2015b; Gomez-Hurtado et al., 2016).