A case of recurrent mass complicated with mitral annular calcification in a patient with systemic lupus erythematosus.

Mitral annular calcification (MAC) is a chronic degenerative process involving the fibrous support structure of the mitral valve. The prevalence of this condition significantly increases with age, and is higher in patients with cardiovascular risk factors or end-stage renal disease. However, patients with systemic lupus erythematosus (SLE) may develop atherosclerosis and MAC at a relatively young age. Caseous calcification of the mitral annulus (CCMA) is a rare subtype of MAC that occurs because of caseous transformation of the inner material. Rarely, CCMA merges with infective endocarditis (IE). This case presented an unusual example of a recurrent mass caused by CCMA after surgery for IE. A 62-year-old Japanese woman was admitted to our hospital with fever of unknown origin. She had a documented history of SLE. Blood cultures were positive, and a transesophageal echocardiography, performed to investigate IE, revealed a mass attached to the CCMA. The patient was diagnosed with IE and underwent lumpectomy. Postoperatively, the patient remained free of fever and embolism; however, the mass recurred. She was considered to have a mass due to CCMA recurrence; although revision surgery was scheduled, the mass resolved spontaneously. Therefore, owing to the risk of recurrence, CCMA requires careful preoperative and postoperative observation. Learning objective: Caseous calcification of the mitral annulus may rarely occur, even in middle-aged patients. This condition carries the risk of infective endocarditis complications and postoperative recurrence, and careful follow-up is required.