CASQ2 and catecholaminergic polymorphic ventricular tachycardia: (b) There was no obvious abnormality in the 12‐lead electrocardiogram at rest in the present CPVT patients, and QTc intervals were within normal parameters; Interestingly, patient 5 with homozygous variant of CASQ2 (c.98G>A/p.R33Q) had relative resting bradycardia (54 bpm), which may be a direct effect of the impaired Ca2+ handling of his sinoatrial nodal cells, as a result of the effect of mutant calsequestrin protein.