In the study by Jung et al. [115], dantrolene, an inhibitor of sarcoplasmic Ca2+ release, which is effective on malignant hyperthermia and is commonly used in the treatment of CPVT patients, restored normal Ca2+ handling properties and rescued the arrhythmogenic phenotype in hiPSC-CMs from a CPVT1 patient carrying the S406L mutation in RyR2. In a successive study, the antiarrhythmic efficacy of dantrolene during exercise testing was assessed in six patients carrying various RyR2 mutations [116]. Here, RYR2 is linked to catecholaminergic polymorphic ventricular tachycardia 1.