Ryanodine receptor stabilization therapy suppresses Ca2+- based arrhythmias in a novel model of metabolic HFpEF

Heart Failure with preserved ejection fraction (HFpEF) has a high rate of sudden cardiac death (SCD) and empirical treatment is ineffective.We developed a novel preclinical model of metabolic HFpEF that presents with stress-induced ventricular tachycardia (VT).Mechanistically, we discovered arrhythmogenic changes in intracellular Ca 2+ handling distinct from the changes pathognomonic for heart failure with reduced ejection fraction.We further show that dantrolene, a stabilizer of the ryanodine receptor Ca 2+ channel, attenuates HFpEFassociated arrhythmogenic Ca 2+ handling in vitro and suppresses stress-induced VT in vivo.We propose ryanodine receptor stabilization as a mechanistic approach to mitigation of malignant VT in metabolic HFpEF.