Mutations in RyR2 are responsible for most cases of CPVT (denoted as CPVT-1) (3, 16), while mutations in calsequestrin (CASQ) are responsible for an even rarer autosomal recessive form of the disease (CPVT-2) (17). This evidence concerns the gene RYR2 and catecholaminergic polymorphic ventricular tachycardia.