Endocrine Abstracts

Hyperthyroidism has a profound effect on the cardiovascular system. Heart failure is common in the elderly patients with hyperthyroidism who have co-existing cardiac disease.

We report a case of severe heart failure in a 43-year-old woman with Graves' disease. She presented with cough and breathlessness for 3 weeks. There was a strong family history of thyroid disease. On presentation, she had florid hyperthyroidism with features of Graves' disease. Examination revealed uncontrolled atrial fibrillation with mitral regurgitation and heart failure. Echocardiogram showed left ventricular and left atrial dilatation associated with anterior mitral cusp prolapse. She was treated with Carbimazole, Digoxin, Propranolol and Furosemide, but had repeated admissions with left ventricular failure. Even when she was euthyroid with a block and replace regimen, she had recurrent episodes of atrial tachyarrhythmias. She had been cardioverted twice, remaining in sinus rhythm after the second procedure. Cardiac function has remarkably improved and mitral valve prolapse is resolving.

This case illustrates heart failure as a presenting feature even in a middle-aged thyrotoxic patient without underlying cardiac disease and highlights the length of time taken for the cardiac failure resolve even when the patient is euthyroid. The structural abnormalities are often reversible.