(Kushnir & Marks, 2010) In patients with RYR2‐related CPVT, intracellular Ca2+ overload due to an increased diastolic Ca2+ leakage from SR in the presence of high β‐adrenergic tone has been thought to be the cause of enhanced U‐waves on electrocardiogram (ECG) and VAs which may be coincident with delayed afterdepolarization (DAD)‐induced triggered activity. Here, RYR2 is linked to catecholaminergic polymorphic ventricular tachycardia.