Storm and STEMI: a case report of unexpected cardiac complications of thyrotoxicosis

Abstract

Background Thyroid storm is a rare condition with well-known cardiovascular manifestations including tachycardia, atrial fibrillation, heart failure, and myocardial infarction (MI). Several uncommon conditions that can mimic MI are associated with thyrotoxicosis and discussed in this case. Case summary A 23-year-old previously healthy male presented after the onset of generalized weakness and inability to rise from bed in the setting of 35 kg of unintentional weight loss, and was found to have profound hypokalaemia, elevated thyroid hormone, and suppressed thyroid-stimulating hormone consistent with thyrotoxicosis secondary to Grave’s disease. Following hospital admission, he developed worsening tachycardia with dynamic anteroseptal ST-segment elevations and elevated cardiac biomarkers concerning for MI. He was treated with aspirin, ticagrelor, and a heparin infusion, but was unable to tolerate beta-blockade acutely due to hypotension. Echocardiography demonstrated a severely dilated left ventricle (left ventricular end-diastolic volume index 114 mL/m2) and severely reduced systolic function (ejection fraction 23%) with global hypokinesis. Following initiation of propylthiouracil, iodine solution, and stress-dosed steroids his tachycardia and ST-elevations resolved. Computed tomography (CT) coronary angiography demonstrated no evidence of coronary stenosis. He was discharged on methimazole, metoprolol, and lisinopril and found to have recovered left ventricular systolic function at 2-month follow-up. Discussion Thyrotoxicosis can rarely cause coronary vasospasm, stress cardiomyopathy, and autoimmune myocarditis. These conditions should be suspected in hyperthyroid patients with features of MI and normal coronary arteries. Workup should include laboratory evaluation, electrocardiography (ECG), echocardiography, and non-invasive or invasive ischaemic evaluation.

Recurrent peri‐myocarditis: A rarer but unfortunate redundant presentation of thyroid storm

“…Thyroid storm, also known as thyrotoxic crisis, is the most severe form of thyrotoxicosis and is typically characterized by organ malfunction and failure 4 . Cardiovascular manifestations are the most severe presentation of thyrotoxicosis, most commonly atrial fibrillation and tachycardia‐induced cardiomyopathy also, coronary vasospasm, and autoimmune myocarditis, all of which can mimic ST‐segment elevation myocardial infarction (STEMI) 1,5 . Excess thyroid hormone levels have also been independently associated with coronary events.…”

“…Thyroid storm is an acute and life‐threatening complication of hyperthyroidism with a significant mortality rate, and about 5% of them have initial heart failure presentation, while others may have cardiac presentations like tachycardia and atrial fibrillation 1 . A few cases are reported in the literature on thyroid storm and its association with peri‐myocarditis.…”

Cardiac Arrest as First Presentation of Thyroid Storm

“…Many of the clinical manifestations of thyrotoxicosis are due to hormonal effects on hemodynamics [ 11 ]. A thyroid storm can cause acute myocardial infarction, coronary vasospasm, stress cardiomyopathy, autoimmune myocarditis, and ventricular arrhythmias [ 1 ]. In this case, we think that a ventricular arrhythmia caused the cardiac arrest of the patient.…”

“…Precisely, the high circulating thyroid hormones have a direct toxic effect on the cardiovascular system. The cardiac manifestations and complications of this condition can include myocardial injury, heart failure, cardiogenic shock, cardiac arrhythmias, and sudden cardiac arrest [ 1 ].…”

Impending myocardial ischaemia during thyroid storm diagnosed through Wellens’ syndrome

“…Patients with hyperthyroidism were detected to have elevated concentrations of vWF and increased platelet plug formation. Thyroid storm could precipitate a myocardial infarction (MI) 6. Our case highlights the possibility that thyroid storm may be associated with an acute coronary event after initial recovery and with unique but rare and specific ECG changes.…”