[Young woman with hyperthyroidism associated with severe tricuspid regurgitation].

Cardiovascular manifestations of hyperthyroidism are frequent and sometimes are relevant in the clinical picture. Usually an hyperdynamic circulatory state hallmarks the disease with low peripheral resistance, increased intravascular volume and cardiac output. However, right chamber dilatation with tricuspid valve regurgitation and cardiac failure are unusual. We present the case of a young woman with Graves-Basedow disease without cardiovascular history who complained about palpitations, peripheral edemas, weight loss and fever. The clinical findings were tachycardia with irregular pulse, right heart failure and regurgitant tricuspid murmur that increased with inspiration. The chest radiograph and the echocardiogram showed right ventricular dilatation and severe tricuspid regurgitation without pulmonary hypertension. The treatment with propranolol, corticosteroids and diuretics was successful. The patient was asymptomatic with sinus rhythm. We discuss the effects of thyroidal hormones on the cardiovascular system and postulate pathophysiologic mechanisms of heart failure in hyperthyroidism.