Amiodarone-induced destructive thyroiditis associated with coronary artery vasospasm and recurrent ventricular fibrillation.

A 55-year-old male on long-term amiodarone therapy presented with ischaemic chest pain and recurrent unwitnessed syncope. Interrogation of his internal cardiac defibrillator, which had been inserted 4 years earlier, revealed two episodes of ventricular fibrillation, the timing of which corresponded to his syncopal events. Severe spontaneous coronary artery vasospasm was observed on coronary angiogram. Thyroid function testing revealed severe hyperthyroidism with a diagnosis of type 2 amiodarone-induced thyrotoxicosis (AIT) subsequently made. Treatment with prednisolone therapy was commenced and thyroid function rapidly normalized. Prednisolone was weaned without recurrence of hyperthyroidism and on last review, 6 months after initial presentation, he remains free from further chest pain and arrhythmias. Our patient's presentation is a very rare case of AIT-associated coronary artery spasm and documented ischaemic ventricular fibrillation with fortunate survival.