DOI 10.1111/jocs.12934 CASE REPORT Spontaneous rupture of a caseous calcification of the mitral annulus in a hemodialysis patient Azumi Hamasaki MD, PhD | Tetsuro Uchida MD, PhD | Mitsuaki Sadahiro MD, PhD Second Department of Surgery, Yamagata University Faculty of Medicine, Yamagata, Japan Correspondence Azumi Hamasaki MD, PhD, Second Department of Surgery, Yamagata University Faculty of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. Email: hamasaki-ths@umin.ac.jp Abstract We report a 56-year-old hemodialysis patient with a spontaneously ruptured caseous calcification of the mitral annulus resulting in multiple cerebral emboli. The mass was resected without replacing the mitral valve. The patient has remained symptom-free 3.5 years following surgery. 1 | INTRODUCTION Caseous calcification of the mitral annulus (CCMA) is a rare variant of mitral annular calcification (MAC) that constitutes 0.63% of all MAC cases and has a prevalence of 0.067% in the general population. 1 Although CCMA is usually a benign and asymptomatic condition, it can cause hemodynamic or embolic complications. 2 We report a 56-year- old female with a spontaneously ruptured CCMA, that resulted in multiple cerebral emboli and required urgent surgery. 1.1 | Case report A 56-year-old female was referred for intermittent claudication. She had a history of type 2 diabetes mellitus and end-stage kidney failure and had been on hemodialysis for 2 years. Physical examination, electrocardiography, and a chest radiography were normal. A mobile, echodense, and spherical tumor-like mass (20 × 15 mm) at the posterior mitral leaflet was incidentally diagnosed by a transthoracic echocardiography (TTE) (Figure 1A). Mild mitral regurgitation was seen but no obstruction was found. A TTE performed 1.5 years prior revealed no intracardiac mass (Figure 1B). Chest computed tomogra- phy showed a calcified mitral annulus. Brain magnetic resonance imaging (MRI) scheduled as a screening examination revealed multiple acute-phase infarctions of the right anterior cerebral cortex and right cerebellum, but no related symptoms were observed. An urgent operation was performed. After the initiation of cardiopulmonary bypass, myocardial protection was achieved using intermittent antegrade and retrograde cold blood cardioplegia. The mitral valve was exposed via a left atriotomy. Visual inspection revealed an empty calcified capsule originating from the posterior mitral leaflet (Figure 2A). The capsule was resected by shaving it off the mitral leaflet which left a 3-mm diameter defect (Figure 2B). The defect was closed by two interrupted monofilament sutures (Figure 2C) which isolated the calcified surface from the bloodstream. The contents of the capsule had completely disappeared (Figure 2D). Aortic cross clamp time and cardiopulmonary bypass time were 65 min and 96 min, FIGURE 1 Preoperative images: transthoracic echocardiography (TTE) demonstrating a mobile, echodense, and spherical tumor-like mass (20 × 15 mm) at the posterior mitral leaflet without acoustic shadowing (A). TTE performed 1.5 years prior showing no intracar- diac mass (B) J Card Surg 2017; 32: 85–87 wileyonlinelibrary.com/journal/jocs © 2017 Wiley Periodicals, Inc. | 85