Very low enrollment

Investigators intend to study the changes in thyroid hormone storage and production in amiodarone-induced thyrotoxicosis patients after RFA therapy.

Investigators plan to identify patients with amiodarone-induced thyrotoxicosis (AIT) that failed to respond to medical therapy or have developed side effects from medical therapy or are considered high risk for such therapy.

These patients will be offered the option to undergo radiofrequency ablation (RFA) of a portion of the thyroid gland in order to decrease thyroid hormone production and/or to inactive the existing thyroid hormone store before their leakage into the circulation.

Investigators will follow these patients to assess their clinical response as well as their thyroid values. The safety of the procedure will also be assessed.

Inclusion Criteria:

• Are adults
• Have overt thyrotoxicosis (within 2 weeks prior to enrollment)
• Are receiving medical therapy for AIT
• Are able to understand the study procedures and to comply with them for the entire length of the study
• Have not normalized their thyroid levels after one month of standard therapy or
• Have persistent and clinically significant thyrotoxicosis (less than 25% decrease in T4 value or patients requiring hospitalization with Congestive heart failure (CHF), tachyarrhythmias, hemodynamic instability or similar co-morbidities) after 2 weeks of standard therapy where additional medical therapy is deemed unlikely to be beneficial or with high risk of side-effects (e.g. hepatotoxicity of antithyroid medications, agranulocytosis of potassium perchlorate or ATD or fluid retention associated with steroids).

Exclusion Criteria:

• Pregnancy
• Patients with prior neck surgery or neck radiation
• Patients with neck anatomy that precludes easy access by RFA to the entirety of thyroid parenchyma
• Patients on anticoagulation therapy
• Patients with comorbidities deemed too high of a risk for general anesthesia
• Treatment with another investigational drug or intervention (within 6 weeks of planned RFA).
• Current drug or alcohol use or dependence that, in the opinion of the site investigator, would interfere with adherence to study requirements.
• Inability or unwillingness of individual or legal guardian/representative to give written informed consent.

Adverse events were collected from RFA procedure to 72 hours post RFA procedure.

Lack of interested & suitable candidates. The one subject enrolled was lost to follow up.