Caseous calcification of mitral annulus.

Caseous calcification of the mitral valve annulus (CCMA) is a rare variant of mitral annular calcification (MAC) (1). Because it is similar in appearance to lesions such as a cyst, a thrombus, a tumor, or an abscess, misdiagnoses and unnecessary surgical treatments have been reported. It is therefore important to consider CCMA in the differential diagnosis of other similarly appeared lesions. We report a 69-year-old man with CCMA detected incidentally by the intraoperative transesophageal echocardiography during coronary artery bypass grafting.