Myxoma Immediately above the Junction of the Inferior Vena Cava and the Right Atrium: A Rare Cause of Budd-Chiari Syndrome

The Budd–Chiari syndrome (BCS) is a rare disorder caused by the obstruction of the hepatic veins or the inferior vena cava (IVC) at the suprahepatic level. This syndrome is developed by either hepatic vein thrombosis or mechanical venous obstruction and leads to centrilobular hepatic congestion with the subsequent development of fibrosis and cirrhosis. Intracardiac tumors have been rarely reported as a cause of the BCS. These tumors usually originate from the atrial septum. Very rarely, they arise either from the junction of the IVC and the right atrium or from the Eustachian valve. There are a few case reports in the literature where atrial tumors have caused the BCS. In these cases, the tumors were malignant, and the patients died shortly after being diagnosed. We describe a 71-year-old female patient who presented with a 3-month history of abdominal pain and protrusion. On physical examination, blood pressure and pulse rate were normal. Jugular venous pressure was about 10 cm. Cardiac examination revealed a systolic murmur, grade IV/VI, in the left sternal border without radiation. Echocardiography showed a large mass (about 6×4 cm) in the right atrium with close contact to the origin of the IVC, obstructing it. Cardiac magnetic resonance imaging, with and without gadolinium, also confirmed the diagnosis. The patient underwent surgery, and the myxoma was removed. The tumor was a large solid mass, 5×4 cm in size, which originated immediately above the entrance of the IVC. The patient is in good condition 1 year afterward. We emphasize that atrial myxomas should be considered in the differential diagnosis of tumors that cause chronic BCS.