Abstract 15193: Libman-Sacks Endocarditis and Cerebrovascular Disease: Role of Microparticles
Background: Libman-Sacks endocarditis and cerebrovascular disease (CVD) manifested as stroke/TIA or focal brain lesions on MRI are common, highly interrelated, and associated with significant morbidity and mortality in patients with systemic lupus erythematosus (SLE). The pathogenesis of Libman-Sacks endocarditis and CVD in SLE is uncertain. Microparticles (MP) are submicron membrane vesicles released by monocytes and platelets following cell activation, injury, or apoptosis. Released MP activate pro-inflammatory and prothrombotic chemokines and cytokines and self-perpetuate inflammation and thrombosis. Thus, we aimed to determine if MP are associated with Libman-Sacks endocarditis and CVD in SLE.
Methods: Twenty-five consecutive patients with SLE, 23 female, and age 36 ± 12 years (range 18-55) underwent clinical evaluations, TEE, brain MRI, and flow cytometry for measurement (counts per μL) of CD14-monocyte-derived MP, CD41-platelet-derived MP, and annexin positive MP (indicative of activated platelet-derived MP). Independent observers interpreted TEE, MRI, and flow cytometry.
Results: Monocyte-derived, platelet-derived, and annexin positive MP were higher in patients with versus those without Libman-Sacks vegetations (all p≤0.05); monocyte-derived MP were higher in patients with versus those without acute stroke/TIA (p=0.002); and annexin-positive MP were higher in those with versus those without focal brain lesions on MRI (p=0.016) (Table 1 ).
Conclusion: These data suggest that monocyte-derived, platelet-derived, and annexin positive MP may be pathogenic risk factors or markers of Libman-Sacks endocarditis and CVD in SLE.
- © 2013 by American Heart Association, Inc.