Takotsubo cardiomyopathy associated with cerebral infarction following surgery for euthyroid goitre

Dear Editor:

Takotsubo cardiomyopathy or stress cardiomyopathy is a disease characterised by acute, transient involvement of the left ventricular apex; it may be triggered by emotional or physiological stressors, including neurological complications.^1,2 In the context of thyroid disease, takotsubo cardiomyopathy has mainly been associated with thyrotoxicosis.³

We present the case of a patient with takotsubo cardiomyopathy and stroke following thyroidectomy.

Our patient was a 74-year-old woman with arterial hypertension, dyslipidaemia, type 2 diabetes mellitus, and depressive disorder. A CT scan performed due to recurrent bronchitis revealed intrathoracic goitre. The patient reported mild discomfort with swallowing and displayed normal thyroid hormone levels. A thyroidectomy was performed by a cervical approach, with no complications; at discharge, she was instructed to take levothyroxine 100 μg every 24 hours. The patient visited the emergency department 8 days later due to a sudden-onset episode of difficulty speaking and chest pain. In-hospital code stroke was activated. The examination revealed symptoms of moderate aphasia, hemianopsia, and mild right-limb hemiparesis (4/5); the patient scored 7 on the National Institutes of Health Stroke Scale (NIHSS). An emergency CT scan was performed as part of the code stroke protocol. The CT perfusion study revealed a pattern compatible with acute subcortical stroke in the left parietal and piriform areas, with 30% mismatch without large-vessel occlusion. Fibrinolysis was the only reperfusion therapy possible in this case, but was contraindicated due to the recent surgery. The patient was therefore admitted to the stroke unit and remained under observation. Laboratory analyses showed a troponin T level of 67 ng/L (normal range, 0-14), TSH of 6.02 µIU/mL (0.27-4.2), and free T4 of 0.99 ng/dL (0.93-1.7). Electrocardiography showed sinus rhythm at 100 bpm, with negative T waves in leads V4-V6. Echocardiography detected circumferential hypokinesis in the left ventricular apex with ejection fraction in the lower limit of normal. An angiography study of the coronary arteries detected no alterations. These findings are compatible with takotsubo cardiomyopathy. Treatment with anticoagulants and beta blockers started at admission improved the patient’s symptoms, and she was discharged 21 days later with mild dysphasia and difficulty reading (NIHSS 1). An echocardiography performed at 3 months showed recovery of cardiac motility and normal ejection fraction. At present, the patient has no neurological or cardiological symptoms.

Takotsubo cardiomyopathy is characterised by transient dysfunction of the left ventricular apex, which presents with symptoms similar to those of myocardial infarction, but in the absence of coronary artery disease. Patients with takotsubo cardiomyopathy present electroencephalography alterations and moderately elevated troponin levels. The pathogenesis of the disease is unclear; an association with a hyperadrenergic state has been suggested.

With regard to thyroid disease, takotsubo cardiomyopathy has mainly been associated with hyperthyroidism,^3–6 but cases have also been described in patients with hypothyroidism, since they may present autonomous nervous system alterations in the form of coronary artery spasm.⁸ Our patient, however, presented subclinical hypothyroidism.

She was a postmenopausal woman, a profile that is consistent with most of the cases reported.⁷ Some series also report history of such cardiovascular risk factors as arterial hypertension (58%), diabetes mellitus (20%), and dyslipidaemia (37%).⁶ Affective disorders may present in up to 42% of patients.⁷

This is the first reported case of takotsubo cardiomyopathy manifesting as stroke after surgery for goitre. The condition is triggered by a stressor in 25%-35% of cases.^6,7 Templin et al.⁷ report neurological involvement in 27% of a sample of 1750 patients with takotsubo cardiomyopathy, and other cases have been reported of epileptic seizures,⁹ subarachnoid haemorrhage,¹⁰ and ischaemic stroke.^11–13 Likewise, cerebrovascular accidents may present during follow-up as a complication of takotsubo cardiomyopathy in up to 8% of cases.⁶

In our case, it is difficult to determine whether the stroke was the cause or the result of takotsubo cardiomyopathy.¹⁴ The first option seems less likely, since the strokes that cause this type of cadiomyopathy have been associated with left insula involvement,¹⁵ whereas our patient presented a stroke in the left subcortical parietal and piriform region, which is not directly associated with the insula.

This issue also has therapeutic implications. If cardiomyopathy were caused by stroke, the stroke would be cryptogenic and a more thorough aetiological study would be necessary. If, on the contrary, cardiomyopathy were the cause of stroke, the patient should receive anticoagulation therapy. We opted for the second hypothesis. After prolonged cardiac monitoring, we decided to suspend anticoagulation therapy, assuming that the cause of stroke had resolved.

In conclusion, takotsubo cardiomyopathy is a multifactorial disease that should be considered in some patients with thyroid disorders. Neurological disease may be the cause or a consequence of the syndrome. This issue should be analysed in future studies to gain a deeper understanding of the pathophysiology of the condition in association with neurological involvement.