Mitral annulus caseous calcification mimicking cardiac mass in asymptomatic patient - multimodality imaging approach to incidental echocardiographic finding.

Background: Caseous calcification of mitral annulus is rather rare echocardiographic finding with prevalence of 0.6% in pts. with proven mitral annular calcification and 0.06% to 0.07% in large series of subjects in all ages. Echocardiographic images of caseous calcification are often heterogenous due to calcium and lipid deposits, and the masses show hyperechogenic and hypoechogenic areas. However the appearance of caseous calcification can imitate that of abscess, tumors and cysts, surgical treatment may not be needed when there is no obstruction.
Case Report: 76-year old obese (BMI 32 kg/m(2)), female patient with history of hypertension, stable coronary artery disease, diabetes type 2 and hyperlipidemia presented with no symptoms of mitral valve dysfunction and had no abnormalities on physical exam. Transesophageal echocardiography identified well-organized, composite, immobile lesion (22×15 mm) localized in the posterior part of the mitral annulus, with markedly calcified margins, and no significant impact on the valve function. In computed tomography (CT) lesion was described as calcified (24×22×17.5 mm), connected with posterior leaflet and posterior part of the mitral annulus, reducing posterior leaflet mobility. CT brought the suggestion of caseous mitral annular calcification. Coming to a conclusion, bearing in mind no mitral valve dysfunction at that time, patient was offered conservative treatment.
Conclusions: Although caseous mitral annular calcification is typically an incidental finding, accurate recognition is needed to avoid mistaking the lesion for a tumor or abscess, which may result in unnecessary cardiac surgery. However this entity is diagnosed on cardiac MRI, multi-modality imaging, especially non-contrast CT, allows for the confident, prospective diagnosis.