The present invention refers to non-human transgenic mammals, preferably rodents, or mice, which comprise a mutation in the gene encoding for the cardiac ryanodine receptor (RyR2).Transgenic animals carrying the amino acid change R4496C in the RyR2 protein show a phenotype similar to that of Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT) (OMIM: 604772). Further provided are methods for using these animals as in vivo model of Catecholaminergic Polymorphic Ventricular Tachycardia and RyR2 dependent arrhythmias, in drug screening and for understanding the molecular basis of RyR2 dependent arrhythmias.