Caseous calcification of the mitral annulus (CCMA) is a rare variant of mitral annular calcification with an estimated prevalence of 0.068 % [1–3]. It is characterized by an echodense outer shell and echolucent core [4]. The posterior mitral annulus is more often affected than the anterior. The inner core of the lesion represents the byproduct of liquefaction necrosis. Pathological examination reveals sterile, amorphous, acellular eosinophilic material with macrophage and lymphocyte infiltration [5].

The clinical course of CCMA is generally benign and often dynamic, with reports of spontaneous resolution of progression [3]. The complications of CCMA include hemodynamically significant mitral stenosis and regurgitation secondary to mass effect [5, 6], as well as erosion of the inner core into the left atrial chamber [7] and the left circumflex coronary artery [8].

A 55-year-old man with end-stage renal failure secondary to Alport’s disease who is undergoing thrice-weekly hemodialysis reports increasing breathlessness with minimal exertion and palpitations. He was noted to have a murmur on auscultation (Figs. 3.8, 3.9, 3.10, 3.11, 3.12, 3.13, and 3.14).