[Left atrial ball thrombus in the SLE patient without organic mitral lesion].

A case of 77-year-old female patient with the left atrial ball thrombus without organic mitral valve lesion is reported. She had a history of SLE for one year and experienced pericarditis 2 months before this admission. A 2-D echo examination at that time did not show any abnormal shadow in the left atrium. The repeated 2-D echo on this admission demonstrated peduncular left atrial thrombus of 2 x 1.5 cm in size. Surgical removal of the thrombus was performed successfully. Her cardiac rhythm was atrial fibrillation, but other possible factors related to the intracardiac thrombus formation such as bradycardia, left atrial dilatation or low cardiac output were not noted. Although lupus anticoagulant and anticardiolipin antibody were negative before the operation, participation of SLE in formation of the left atrial thrombus was highly suspected.