Surgical management of amiodarone-induced thyrotoxicosis

OBJECTIVE: Amiodarone can cause thyroid dysfunction in patients with or without previous thyroid disease. With increased use from its placement in advanced cardiac life support guidelines and cardiac transplant programs, the incidence of amiodarone-induced thyrotoxicosis (AIT) will likely increase. Medical management is complex and nonuniform and frequently fails. This study investigates the role of surgery in AIT and proposes indications for surgical management. STUDY DESIGN AND SETTING: Two AIT case reports at a tertiary care institution and 31 surgical AIT cases in the world literature are reviewed. METHODS: The 2 AIT cases involved patients with cardiomyopathy and resistant arrhythmias. Despite medical therapy, both patients' conditions failed to improve. Thirty-one surgical cases of AIT in the literature are evaluated with respect to symptoms and onset, medical therapy, AIT classification, pathology, perioperative management, and complications. RESULTS: Both patients underwent total thyroidectomy without difficulty or complication, one as an overnight stay and one as an inpatient with an intraaortic balloon pump. One patient received a successful cardiac transplant and the other remains a viable candidate. In the literature, the majority (80%) of surgical cases are AIT type II (less common type) with no underlying thyroid disease. Range and duration of symptoms varied, in addition to type and duration of medical management. Almost all patients underwent total thyroidectomy, and all were successful with no mortality and minimal morbidity. CONCLUSION: AIT can develop in any patient during or after amiodarone therapy. Medical management is extremely difficult due to the absence of a proven therapeutic armamentarium, and surgery offers a safe, viable option. Surgical management should play a larger role in treatment algorithms and should be strongly considered for patients whose conditions necessitate continuation of amiodarone, or with severe symptoms resistant to medical therapy.