Surgical experience with caseous calcification of the mitral annulus: a case report.

Caseous calcification of the mitral annulus (CCMA) is a rare variant of mitral annular calcification associated with an increased risk of embolic stroke and diagnostic difficulty. We report a surgical case of CCMA that showed rapid enlargement after the initiation of hemodialysis. A 71-year-old woman undergoing hemodialysis for 1 year presented with a rapidly enlarging mass at the P3 segment of the posterior mitral annulus. Echocardiography and computed tomography revealed a calcified mass with a hypoechoic/low-attenuation core. Intraoperatively, the lesion contained creamy caseous material, and mitral valve replacement with annular reconstruction was required after debridement. Histopathology confirmed CCMA without malignancy or infection. CCMA may progress rapidly in patients on hemodialysis, likely due to disordered calcium-phosphorus metabolism and chronic inflammation. Early surgical intervention with complete isolation of caseous material may help prevent systemic embolism.