Amiodarone-Induced Thyrotoxicosis Presenting as Congestive Heart Failure Exacerbation and Thyroid Storm: Role of Plasmapheresis in Management and Prevention of Complications

Amiodarone-induced thyrotoxicosis (AIT) is a subtype of thyrotoxicosis caused by the long-term administration of the antiarrhythmic drug amiodarone. It’s classified into type 1 AIT, which is defined as hypersecretion of the thyroid hormone, while type 2 AIT is destructive thyroiditis leading to increased release of thyroid hormone. Each type has its special management and diagnostic features. We report a case of a 72-year-old male with a history of heart failure with reduced ejection fraction (HFrEF) and type 2 diabetes mellitus (DM) who presented with congestive heart failure (CHF) exacerbation and symptoms of an impending thyroid storm. After the diagnosis of type 2 AIT, medical treatment, as well as plasmapheresis, was initiated. In further admissions, the patient returned with ventricular tachycardia and right subclavian deep venous thrombosis due to recurrent catheterization and a hypercoagulable state. The diagnostic workup revealed elevated free T4, suppressed TSH, and initially elevated AST and ALT, which normalized subsequently. Imaging showed decreased thyroid vascularity. This case report highlights the importance of distinguishing between AIT types, tailoring optimal treatment decisions, closely monitoring and following up on such cases, and adhering to treatment to prevent catastrophic complications. Further research is necessary to identify early markers of amiodarone toxicity to prompt early diagnosis and better prognosis.