Thyrotoxicosis-an uncommon cause of heart failure

Michael Froeschl1, Haissam Haddad, A Susan Commons

  • 1Division of Cardiology, University of Ottawa Heart Institute, Ottawa, Ontario, Canada.

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Hyperthyroidism is a type of thyrotoxicosis characterized by the thyroid gland's overproduction of the thyroid hormones triiodothyronine (T3) and thyroxine (T4). This hormone excess increases the basal metabolic rate and enhances sensitivity to catecholamines.DiagnosisDiagnosis is based on clinical features and biochemical testing. It typically shows suppressed thyroid-stimulating hormone (TSH) levels below 0.4 mIU/L, with elevated free T3 and/or T4. Additional tests, including thyroid...
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