[Left atrial free-floating ball thrombus in a patient without mitral valve disease]

A free-floating ball thrombus in the left atrium is a rare clinical problem with potentially catastrophic consequences. Thus, early diagnosis and prompt surgical intervention are mandatory. This report dealt with a free-floating ball thrombus in the left atrium in a case without mitral valve disease. A 82-year-old woman was presented with dyspnea, hypotension, and fever. On admission she had cardiac arrhythmia, but had no cardiac murmur. The electrocardiogram revealed atrial fibrillation. Chest X-ray examination showed marked cardiomegaly (cardio-thoracic rate; 94%) without evidence of pulmonary venous congestion. Coagulation studies revealed decreased coagulability. Transthoracic and transesophageal echocardiograms showed retention of pericardial effusion, and a free-floating ball thrombus in the dilated left atrium. Thickening, calcification, and restricted motion of the mitral leaflets were not observed by echocardiography. Removal of the free-floating ball thrombus in the left atrium was successfully performed on the emergency basis. The intact mitral valve was also confirmed at operation. The patient recovered uneventfully. Usefulness of echocardiography, particularly transesophageal echocardiography, for precise diagnosis and intraoperative management of a free-floating ball thrombus in the left atrium is discussed.