RYR2 and cardiomyopathy: A cardiac isoform of the ryanodine receptor does exist, RYR2, and mutations in this gene lead to a phenotype of catecholaminergic polymorphic ventricular tachycardia (CPVT) and a cardiomyopathy syndrome known as arrhythmogenic right ventricular dysplasia type 2 (ARVD2) (Amador et al., 2013).