RYR2 and catecholaminergic polymorphic ventricular tachycardia: This experimental setup was designed to simulate the situation in certain heart diseases such as congestive heart failure (CHF) or catecholaminergic polymorphic ventricular tachycardia (CPVT) when RyR2 is substantially active during diastole; however, the results suggested that the autoregulation of Ca2+ release is broken in these conditions.