RYR2 and ventricular tachycardia: For example, mice heterozygous for RyR2 variant RyR2 variant Arg‐176‐Glu (R176Q) are susceptible to ventricular tachycardia after injection of caffeine and epinephrine, or following programmed ventricular stimulation and administration of β‐adrenergic receptor agonist isoproterenol (ISO).18