Mitral annular calcification-related calcified amorphous tumor in a patient with normal renal function: a case report

A calcified amorphous tumor (CAT) of the heart is a non-neoplastic mass, characterized by nodules of calcium on a background of amorphous fibrinous material. Mitral annular calcification (MAC) is one of the conditions most frequently associated with CAT. Most MAC-related CAT cases are reported in end-stage renal disease (ESRD) patients. This report is a description of a patient with normal renal function who was incidentally diagnosed with a CAT arising from MAC. An asymptomatic 43-year-old man with normal renal function underwent echocardiography. The echocardiography results revealed a highly mobile hyperechoic mass attached to the atrial side of the mitral annulus superimposed on a heavily calcified mitral annulus. Cardiac surgery and histopathological evaluation confirmed a diagnosis of MAC-related CAT. While MAC-related CAT is usually associated with ESRD patients, the precise etiology and management strategy of this benign tumor remain unclear. The rare incidence of this tumor in patients with normal renal function highlights the importance of further research of the pathology of this uncommon condition.