Recurrent Ventricular Fibrillation Associated With Graves' Disease: A Case Report

Although tachyarrhythmias are associated with thyrotoxicosis, the association with ventricular fibrillation is unknown. This case reports a recurrent ventricular fibrillation with Graves' disease that was successfully treated with an implantable cardioverter defibrillator. A 33-year-old woman presented with ventricular fibrillation cardiac arrest. She was diagnosed with Graves' disease and was taking antithyroid drugs, but her hyperthyroidism was poorly controlled. The patient received intensive care unit care, including extracorporeal membrane oxygenator, ventilator, and renal replacement therapy. Implantable cardioverter defibrillator was implanted for the secondary prevention of ventricular fibrillation. Two months after the procedure, ventricular fibrillation recurred, and an implantable cardioverter defibrillator successfully prevented sudden cardiac death. She maintained a normal sinus rhythm and normal thyroid function after receiving radioactive iodine-131 therapy. Ventricular fibrillation is a rare but fatal manifestation in patients with hyperthyroidism. Implantable cardioverter defibrillator should be considered, especially in patients with poorly controlled hyperthyroidism, for the prevention of sudden cardiac death.