Distinguishing aortic valve thrombus from Libman-Sacks endocarditis in antiphospholipid syndrome: imaging and management.

Aortic valve (AV) thrombus, a rare complication of antiphospholipid syndrome (APLS), is important to distinguish from Libman-Sacks endocarditis because of its responsiveness to anticoagulation. This may be attributed to immunopathologic differences underpinning their development. We present the case of a 45-year-old woman with high-risk primary APLS who developed an AV mass and was taken for valvular repair surgery but found to have pure thrombus and normal valve leaflets. In such cases, a trial of conservative management with anticoagulation may be adequate. Echocardiography, computed tomography and MRI findings suggestive of thrombus without endocarditis are presented. A literature review of histopathologic, imaging and treatment implications of pure AV thrombus in the context of APLS is included.