ntiphospholipid syndrome (APS) is a combination of the clinical symptoms of arterial and venous thromboembolism and the presence of autoantibodies such as anticardiolipin 2 GPI antibody, the lupus anticoagulant and the antibodies responsible for the falsepositive serologic test result for syphilis. Primary APS (PAPS) is defined by the presence of these antibodies and thromboembolic phenomena without systemic lupus erythematosus (SLE) and other disease processes. Intracardiac thrombi have been reported, 1-7 but involvement of the tricuspid valve is extremely rare. 5 We report a case of PAPS with a lobulated thrombus on the tricuspid valve, which formed after implantation of a filter in the inferior vena cava (IVC) and resolved with fibrinolytic therapy.
Case ReportA 62-year-old woman was admitted with progressive shortness of breath and tachypnea. The patient's medical history included a 15-year history of bronchial asthma, and a pulmonary embolism caused by a deep vein thrombus 5 years previously. At that time, computed tomography (CT) revealed a large thrombus in the main pulmonary artery, which dissolved with intravenous administration of tissue plasminogen activator. Although several perfusion -ventilation mismatch areas remained on the pulmonary perfusion scan after the therapy (segment 6 on the left, segment 8 on the right), she was discharged with no symptoms after the implantation of an IVC filter. Further evaluation during Circulation Journal Vol. 66, April 2002 that admission led to the diagnosis of PAPS with positivity for lupus anticoagulant. The anticardiolipin 2 GPI antibody level was less than 1.2 U/ml. Antinuclear antibodies were negative, and the activities of proteins C and S were normal, consistent with the diagnosis. She had no history of spontaneous abortion and had delivered normally with 3 pregnancies. After discharge, she was treated with warfarin with a target international normalized ratio (INR) of 2.0 at an outpatient clinic.One year later, she was admitted to examine her pulmonary pressure and right heart pressure, which were found to be in the normal range. A repeat pulmonary perfusion scan showed no change. She continued to be positive for lupus anticoagulant at the second admission. Since then, she has been followed at an outpatient clinic and managed with warfarin bronchodilator and warfarin. However, the warfarin therapy was discontinued 10 months prior to her third admission.On the third admission, she had an oxygen saturation of 89%, a respiratory rate of 28 breaths/min, and a 12-lead ECG that showed an inverted T wave in leads V1-3. Chest X-ray suggested dilatation of the right pulmonary artery. Laboratory tests revealed a white blood cell count of 12,500/mm 3 , hematocrit 41.7%, and platelet counts 124,000 /mm 3 . Transthoracic echocardiography revealed a 1.7×1.8 cm, lobulated, isoechoic, highly mobile mass on the septal leaflet of the tricuspid valve (Fig 1). The right atrium and ventricle were dilated and mild tricuspid regurgitation was detected, with an estimated pulmon...