Caseous Calcification of the Mitral Annulus With Atrial and Ventricular Fistulization

A 65-year-old women with past medical history of hypertrophic cardiomyopathy, prior myocardial infarction, hypertension, and transient ischemic attack presented in cardiology clinic with increased dyspnea (New York Heart Association class II) with no features to suggest endocarditis. The patient underwent a transthoracic echocardiogram, which showed features of hypertrophic cardiomyopathy and moderate mitral regurgitation. A cardiac magnetic resonance examination was performed for further evaluation. Cardiac magnetic resonance demonstrated features of hypertrophic cardiomyopathy, as well as a 4×3 cm ovoid cavity at the inferolateral aspect of the mitral annulus with signal intensity similar to the blood pool (Figure 1A and 1B). Communication between this ovoid cavity and the left atrium was seen (Figure 1A and 1B; Movies I and II in the Data Supplement). These findings were concerning for pseudoaneurysm versus caseous necrosis of mitral annulus calcification with rupture into the left atrium. Late gadolinium enhancement images identified peripheral enhancement of the residual mitral annulus with central cavitation (Figure 1C). Cardiac computed tomography and transesophageal echocardiogram were also performed to characterize the lesion better. Cardiac computed tomography demonstrated a contrast filled space between the posterior mitral valve and basal lateral myocardial wall with a peripheral rim of calcification (Figure 2A and 2B). In comparison, the previous computed tomographic scan from 8 years prior showed mitral annular calcifications (MACs) with no …