TANGO2 and ventricular fibrillation: Examples include acetazolamide treatment for CACNA1A mutation, surveillance for arrhythmias in GNB5 and TANGO2, and mitochondrial-specific surveillance for cardiac, renal, and liver involvement in FBXL4. For patients with the SCN1B variant, current practice guidelines suggest treatment with isoproterenol as a first-line agent for electrical storm (ventricular fibrillation) and consideration of an implantable cardioverter defibrillator (ICD) to prevent sudden death [78].