Takotsubo cardiomyopathy in the setting of thyroid storm

A woman in her 50s with a background of chronic obstructive pulmonary disease secondary to smoking presented with intermittent chest tightness, dyspnoea and vomiting for 4 days. A presumed diagnosis of acute coronary syndrome (ACS) was made based on dynamic ischaemic ECG changes and elevation in high-sensitivity cardiac troponin T levels. She underwent emergent coronary angiography which demonstrated mild coronary artery disease with left ventriculography suggestive of mid-wall variant Takotsubo cardiomyopathy. Thyroid function tests performed to investigate sinus tachycardia were consistent with hyperthyroidism, and her thyroid-stimulating hormone receptor antibody was elevated. A diagnosis of thyroid storm was made in the setting of a newly diagnosed Graves' disease and the patient was subsequently commenced on guideline-based therapy. This case demonstrates that Takotsubo cardiomyopathy, a mimic of ACS, is a possible complication of thyroid storm and therefore hyperthyroidism should be considered in the list of differentials in patients presenting with Takotsubo cardiomyopathy.