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 longterm. This case also highlights a simple and effective treatment for amiodarone-induced MC.

Amiodarone Induced Myxedema Coma: A Systematic Review of Case Reports

“…One study scored (100%) for all questions [10], and four case reports scored 87.5% [2,16]. Also, ve case reports scored 75% [17][18][19][20][21]. However, only one study scored 62.5% [22], as well only one study scored 50% [23]; see Table (2).…”

“…[Please insert Table 3 here] Altered mental status was also represented in ten case reports (34.5%) [10,16,17,[20][21][22][23][24][25][26], and eight cases (27.6%) reported bradycardia as a subsequent recurrent symptom among patients [2,10,16,18,22,[24][25][26]. However, hypothermia and hypotension were reported about in half of the cases.…”

“…However, hypothermia and hypotension were reported about in half of the cases. Additionally, nine cases (75%) reported that the patients had no previous thyroid dysfunction [10,17,20,21,23,25, 26], while three case reports (25%) their patients had hypothyroidism [18,22,24]. Half of the included cases (50%) reported T3 and T4 levels [2,17,20,21,24,25], while the remaining did not [10,16,18,22,23,26].…”

“…For TSH, almost all cases reported the TSH level. Four cases (33.3%) pointed out TSH results between 50 and 100 mIU/L [16,18,22,25], the other four reported more than 100 mIU/L [2,20,21,24], and three (25%) reported TSH between 14 and 44 mIU/L [10,17,26]. Upon diagnosis with myxedema coma, treatment in hospitals includes levothyroxine and hydrocortisone.…”

“…Different doses of levothyroxine were reported in seven cases; four cases (33.3%) pointed out 200 mcg, and three cases in each study had different doses, including 75mg [26], 100mg [24], and 250 mg [16]. However, ve cases (41.6%) didn't mention the dose of levothyroxine [2,17,[21][22][23]. For hydrocortisone dose, seven cases mentioned the prescribed dose; three cases (25%) pointed out 100 mg of hydrocortisone [10,18,24], as well two cases (16.6%) pointed out 50 mg [25,26], and one study (8.3%) pointed out 200 mg of hydrocortisone [16].…”