We herein report a 61-year-old woman with a history of mitral valve replacement for rheumatic fever who presented with crural edema and ascites. Computed tomography showed massive left atrial (LA) calcification involving the interatrial septum, termed "coconut atrium." Catheterization revealed not only pulmonary artery hypertension but also a large V-wave in the pulmonary artery wedge pressure waveform and a dip-and-plateau pattern of right ventricular pressure. Three-dimensional transthoracic echocardiography confirmed the early attainment of peak LA volume and a decreased LA expansion index. Stiff LA syndrome due to coconut LA results in the development of restrictive right ventricular physiology.

Massive calcification of the left atrium is an uncommon complication of long-standing rheumatic valve disease, and is frequently revealed in patients with a previous operation on the mitral valve. An 84-year-old woman, who had a history of rheumatic valvulopathy and mitral-aortic valve replacement surgery 35 years previously, was admitted to our hospital due to congestive heart failure. Chest X-ray showed severe cardiomegaly with rim of calcification outlining the enlarged left atrium. Computed tomographic scan of the thorax clearly illustrated dense and partially thick plate-like calcification of left atrial free wall and interatrial septum. She died due to congestive heart failure 14 days after hospitalization and an autopsy was performed. Enlargement of left atrium with massive calcification was evident by gross pathology. Thick plate-like calcification with both erosion and mural hemorrhage was clearly shown by a cross-section of atrial wall. Organized and fresh fibrin thrombi were identified at the surface of left atrium. Calcified tissue penetrated into the wall of the left atrium and lack of myocardium underneath the massive calcified lesion was evident. Although rheumatic calcification of left atrium revealed by medical images was previously described, this is the first case report that demonstrates histopathological evaluation of massive atrial calcification. <Learning objective: Rheumatic calcification of entire left atrium after valve replacement surgery is known. Erosive calcification of the atrial wall with mural thrombi was identified by histology in this case. Old renal infarction was revealed by autopsy; therefore calcified atrium could be a source of distal embolism. Transmural calcification penetrated into the left atrial wall. We speculate on the difficulty in finding a cleavage plane for the endoatriectomy of massive calcified atrium in such a situation.>.

Dystrophic cardiac calcification is often associated with conditions causing systemic inflammation and when present, is usually extensive, often encompassing multiple cardiac chambers and valves. We present an unusual case of dystrophic left atrial calcification in the setting of end stage renal disease on hemodialysis diagnosed by echocardiography and computed tomography. Significant calcium deposition is confined within the walls of the left atrium with no involvement of the mitral valve, and no hemodynamic effects.