A Rare Occurrence of Dilated Cardiomyopathy and Long Qt Syndrome in a Child with Graves’ Disease: A Case Report and Review of Literature

Grave’s disease (GD) is the most common cause of hyperthyroidism in children and typically patients exhibit symptoms of hyperthyroidism such as palpitations, sweating, heat intolerance, diarrhoea and weight loss. Cardiomyopathy is a rare but serious and life-threatening complication of GD. It is more prevalent among middle-aged and elderly patients with pre-existing heart conditions. We describe a case of an 11-year-old girl with Graves’ disease complicated by thyroid storm, and dilated cardiomyopathy. She had palpitations for almost 2 years, followed by recurrent syncopal attacks for 6 months. The initial thyroid function test showed significantly high FT4 levels of 85.6pmol/L and suppressed TSH. Her TSH Receptor antibody (TRAB) was positive and her CXR revealed cardiomegaly. She received anti-thyroid drugs including oral Carbimazole, oral propranolol, Lugol’s iodine and intravenous hydrocortisone. Two anti-failure medications were used to treat her heart failure. Her symptoms improved, and she was discharged with oral carbimazole and oral propranolol. It is important to recognise and diagnose the complications associated with severe GD to prevent future cardiac decompensation during relapse. Medical practitioners need to be aware of the rare presentations of Graves’ disease to avoid delayed diagnosis and treatment.