An Extensively Calcified Right Atrial Myxoma

Abstract

A 52-year-old woman presented with dyspnea on exertion, chest discomfort, and two episodes of orthostatic syncope within 1 month. Cardiac auscultation revealed splitting of S1 sound without murmur. A huge, oval-shaped, calcified mass was found in the cardiac silhouette (Fig 1). Transthoracic echocardiography revealed right atrial (RA) dilatation, with a sessile mass occupying almost the entire RA chamber and causing diastolic obliteration of the tricuspid valve. Computed tomography showed an extensively calcified, interatrial septum-abutted the RA mass of 6 cm diameter (Fig 2).Fig 2View Large Image Figure ViewerDownload (PPT) She subsequently underwent removal of the tumor. A mass with a yellowish, smooth surface and a stone-like consistency was adhered to the interatrial septum and was excised (Fig 3). The histopathologic examinations of the mass revealed hyalinized fibrotic thrombus with extensive calcification. The final diagnosis was a degenerative calcified RA myxoma. Myxoma is the commonest primary benign cardiac tumor in adults [1Reynen K. Cardiac myxomas.N Engl J Med. 1995; 333: 1610-1617Crossref PubMed Scopus (1030) Google Scholar]. Approximately 75% of myxomas arise in the left atrium, and 15% to 20% in the RA [2McAllister Jr., H.A. Fenoglio Jr., J.J. Tumors of the cardiovascular system. Atlas of tumor pathology. 2nd series. Fascicle 15. Armed Forces Institute of Pathology, Washington, D.C.1978: 1-20Google Scholar]. Calcification can observed in 10% to 20% of myxomas, but heavy calcification of an atrial myxoma is uncommon [3Sharratt G.P. Grover M.L. Monro J.L. Calcified left atrial myxoma with floppy mitral valve.Br Heart J. 1979; 42: 608-610Crossref PubMed Scopus (12) Google Scholar], and visible calcification from a plain chest roentgenogram is extremely rare [3Sharratt G.P. Grover M.L. Monro J.L. Calcified left atrial myxoma with floppy mitral valve.Br Heart J. 1979; 42: 608-610Crossref PubMed Scopus (12) Google Scholar, 4Stewart J. Saunders N.R. Left atrial myxoma with extensive calcification.Thorax. 1982; 37: 224-225Crossref PubMed Scopus (3) Google Scholar]. The tumor caused interruption of right ventricular filling and low cardiac output symptoms. Successful tumor removal finally gave her a prompt and full recovery.