Left atrial thrombus without mitral valve disease in a patient with nephrotic syndrome: Report of a case

Left atrial (LA) thrombi are rarely seen in patients without mitral valve disease. We report the case of a 71-year-old man found to have a large LA thrombus without mitral valve disease. The patient also suffered from atrial fibrillation and nephrotic syndrome (NS), and had a history of transient ischemic attack. Transesophageal echocardiography showed an LA thrombus attached to the LA wall, and a normal mitral valve. Blood chemistry revealed a total serum protein of 4.6 g/dl, with 2.0 g/dl of albumin and a total cholesterol level of 453 mg/dl. The plasma fibrinogen level was 366 mg/dl and the antithrombin III was 103%. An emergency operation was performed to remove the LA thrombus and a normal mitral valve was confirmed. We believe that several factors, including changes in coagulability related to the NS, steroid therapy, and diuretics, in addition to the dilated LA with atrial fibrillation, may have caused the LA thrombus formation in this patient.