Thyrotoxic cardiomyopathy is the initial clinical presentation in approximately 6% of patients with hyperthyroidism. Graves’ disease is an important cause of cardiomyopathy because it is reversible in most patients if euthyroid state achieved with antithyroid medication timely. From other side the association of thyrotoxicosis and cardiovascular morbidity is well established. Prompt diagnosis of thyrotoxicosis and rapid approaching of euthyroid state shown to improve clinical outcomes. The abnormal left ventricular function observed in hyperthyroidism. This report is to present a case of Graves’ thyrotoxicosis-induced cardiomyopathy. This is a case of a 61 year old woman who been presented with symptomatic congestive heart failure and was subsequently diagnosed with dilated cardiomyopathy secondary to Graves’ disease and atrial fibrillation. On echocardiography initial left ventricular systolic ejection fraction was of 38%. After treatment with anti-thyroid agents she improved clinically. Normalization of her ejection fraction occurred. So, patients with dilated cardiomyopathy should routinely be screened for hyperthyroidism. More studies need to be done to correctly define role of thyroid hormones in pathophysiology of dilated cardiomyopathy. We expect that this case report will contribute to the existing literature on this subject.

 

Keywords: Graves’ disease, Thyrotoxicosis, Cardiomyopathy, Congestive heart failure