Right Heart Failure and Hyperthyroidism: A Neglected Association

Abstract

Background: Hyperthyroidism is a hyperkinetic syndrome related to an excess of circulating thyroid hormones. We report the case of a patient with Grave's disease who was admitted for right heart failure due to reversible thyrotoxic tricuspid regurgitation. Case report: A 65-year-old patient, without medical history. He was admitted with dyspnea and bilateral leg edema. The examination revealed a tachycardia with signs of right heart failure. The electrocardiogram showed atrial fibrillation with an average ventricular rate of 112 beats per minute and low voltage in the frontal leads.Transthoracic echocardiography showed a very dilated right ventricle with a paradoxical septum motion. The tricuspid valve presents a lack of coaptation affecting the three leaflets which is responsible for massive tricuspid regurgitation. The inferior vena cava was dilated without collapse. Biological testing showed a very low thyroid-stimulating hormone (<0.003) and a high T4 and T3. Immunological testing confirmed Grave's disease. Our treatment approach was built on diuretics and treating hyperthyroidism with antithyroid drugs. We eliminated every etiology that would justify a functional tricuspid regurgitation. The evolution was marked by a regression of the congestive signs, a return to sinus rhythm after 40 days of treatment and a regression of both the tricuspid regurgitation and the dilation of the right ventricle nine months after antithyroid therapy. Conclusion: This is a case of cardiothyreosis complicated by right heart failure caused by severe tricuspid regurgitation which is reversible under antithyroid therapy. We underline the advisability of carrying out a systematic thyroid assessment when presented with unexplained right heart failure.