Two Cases of Calcified Amorphous Tumor Mimicking Mitral Valve Vegetation

Abstract

The term cardiac calcified amorphous tumor (CAT) was coined in 1997 by Reynolds et al,1 who described 11 cases with nonneoplastic cardiac masses characterized by a pedicle and diffuse calcification. Additionally, CAT could originate in any of the 4 chambers. Once the mass is excised, its unique histological features such as the presence of calcified nodules in an amorphous background of fibrin with degeneration and focal inflammation allow an accurate diagnosis of cardiac CAT. However, in cases when CAT has arisen close to the cardiac valves and is mobile, it is not always easy to distinguish between CAT and mitral valve vegetation preoperatively. Here, we report 2 cases of CAT arising from mitral annular calcification (MAC) and propose imaging features that can be used to distinguish CAT from mitral valve vegetation. Case 1. A 58-year-old man with end-stage renal disease secondary to diabetic nephropathy was referred to our hospital. He had been maintained on hemodialysis for the past 4 years. Transthoracic echocardiography revealed 2 cardiac tumors adherent to the posterior MAC (Figure 1A). One was a highly mobile, …