CALM2 and familial long QT syndrome: Perturbation of this CaM‐facilitated communication between Kv7.1 and [Ca2+]cyt is prone to cause ventricular arrhythmia either through an abnormal enhanced IKs (promoting short QT syndrome) or diminished IKs generation (promoting LQTS) (Bartos et al., 2017; Nitta et al., 1994; Rudic et al., 2014; Tohse, 1990).