Abstract 11379: Libman-Sacks Endocarditis Mimicking Intracardiac Tumor in a Patient With Systemic Lupus Erythematosus and Secondary Antiphospholipid Syndrome

Abstract

A 43-year-old woman, with history of SLE for 12 years and secondary APS for 10 years. Hospitalized in 2016 by pulmonary embolism, finding on that occasion the presence of intracardiac mass in the right atrial, at that time, she was pregnant and had full anticoagulation with LMWH until the end of the pregnancy. Since then, in treatment with azathioprine, hydroxychloroquine and acenocoumarin irregularly. She presented to the ER with a 21-day history of abdominal distention and diffuse pain, dyspnea at rest, and bilateral lower extremity pitting edema. On presentation patient was normotensive and tachycardic, in anasarca and with a loud holosystolic murmur at the parasternal border, in fifth intercostal space. Was admitted for acute heart failure. In TTE, the persistence of the right atrial mass dependent on interatrial septum with greater growth than the previous one was observed. The tumor protruded within the entrance tract of the right ventricle during diastole and during systole a doble jet of severe tricuspid regurgitation is observed. The tricuspid valve was thickened. A contrasted enhanced cardiac magnetic resonance confirmed the presence of the tumor described above without contrast uptake. The patient underwent mass excision surgery with preoperative diagnosis of atrial myxoma. Microscopic examination of the excised material revealed dispersed lymphohistiocytic infiltrate and thrombi without evidence of microorganisms, compatible with Limban-Sacks endocarditis. Because of the size and location of the lesion, Libman-Sacks endocarditis was considered highly unlikely. Only few cases of a vegetation simulating an intracardiac mass have been reported and in these patients analysis of serologic markers showed that lupus anticoagulant was positive, anticardiolipin antibodies IgM-G and antiphospholipid antibody were high.