Amiodarone-Induced Myxedema Coma

Abstract

Amiodarone is a class III antiarrhythmic drug often used to treat supraventricular and ventricular arrhythmias with high efficacy. Amiodarone is associated with thyroid dysfunction, which can lead to myxedema coma (MC) in undiagnosed cases. Amiodarone-induced MC is a life-threatening condition that presents a complex diagnostic challenge to emergency physicians. A 71-year-old male with a past medical history of congestive heart failure presented unresponsive to the emergency department with bradycardia and syncope. His medications included amiodarone. Work-up showed hypothermia, thyroid-stimulating hormone (TSH) of 52.2 uIU/mL, and low free T(4) of 0.64 ng/dL. This case suggests the importance of thyroid panels in the management of patients who are using amiodarone long-term. This case also highlights a simple and effective treatment for amiodarone-induced MC.