Amiodarone-associated thyrotoxicosis (AAT): experience with surgical management.

Amiodarone (Cordarone), a benzofuran derivative containing two atoms of iodine per molecule (37% of molecular weight), has recently been released in the United States for the management of refractory cardiac arrhythmias. While it was still under investigation, 529 patients were managed with this drug at the Mayo Clinic between 1981 and 1986; eight of them (1.5%) had thyrotoxicosis 12 to 37 months (median, 28 months) after initiation of treatment. Low 24-hour iodine-131 uptake (less than 4%) and recognized refractoriness to thionamide treatment precluded the use of radioablation or antithyroid drugs. Cessation of the amiodarone treatment was considered undesirable from a cardiac standpoint. Near-total thyroidectomies were undertaken in six patients, and rapid correction of hyperthyroidism followed. There were no intraoperative or postoperative arrhythmias. The median postoperative hospital stay was 4.3 days (range, 2 to 13 days). Subsequently, all patients required thyroid hormone replacement. Near-total thyroidectomy has proved a safe and effective treatment for amiodarone-associated thyrotoxicosis in patients who required drug continuation.