A female patient was admitted to our Department for total thyroidectomy in 
amiodarone-induced thyrotoxicosis. The drug was prescribed for ventricular 
arrhythmia and atrial paroxysmal fibrillation in dilated cardiomyopathy due to 
chronic aortic regurgitation with left ventricular dysfunction (ejection 
fraction 35%; Class Functional NYHA III) and moderate-severe respiratory 
insufficiency. The cardiologist-anesthetist team has allowed to evaluate the 
surgical-cardiovascular-anesthesiologic risks and the balance between the 
improvement by the amiodarone administration for the arrhythmia, and the 
discontinuation of this treatment in order to prevent aggravation of the 
thyrotoxicosis. These hypotheses were subsequently discharged for the two 
reasons listed below: - several other antiarrhytmic drugs (that didn't show 
equivalent efficacy as amiodarone in preventing or converting such ventricular 
and atrial arrhythmias) may be proposed in the place of amiodarone. However, 
this could expose the patient to an arrhythmia; - a clear proof that the 
suspension of amiodarone can allow restoring normalization of the thyroid 
function doesn't exist. Therefore, the patient has been successfully submitted 
to the surgical intervention and in the follow-up we brought her back to a state 
of normalized thyroid function and cardiovascular conditions. In patients that 
cannot safely discontinue amiodarone or when medical therapy is ineffective in 
controlling thyrotoxicosis, thyroidectomy is the treatment of choice.