In the initial study, the antiarrhythmic mechanism of flecainide in CPVT was the suppression of abnormal calcium release from the sarcoplasmic reticulum (SR) by targeting the cardiac ryanodine receptor (RyR2; Watanabe et al., 2009; Hilliard et al., 2010; Hwang et al., 2011). The gene discussed is RYR2; the disease is catecholaminergic polymorphic ventricular tachycardia.