RYR2 and catecholaminergic polymorphic ventricular tachycardia: On the other hand, other groups have suggested that PKA phosphorylation of RyR2 is so essential to intracellular Ca2+ homeostasis that derangement of this process may be the basis for heart failure (HF) [37,90] and catecholaminergic polymorphic ventricular tachycardia (CPVT) episodes [91].