Mitral valve prolapse in systemic lupus erythematosus.

Despite a low incidence of clinical manifestations, autopsy data suggest endocardial and myocardial disease in about 50% of patients with systemic lupus erythematosus. To investigate whether mitral valve prolapse can be considered a clinical manifestation of cardiac involvement in systemic lupus erythematosus, we carried out an echocardiographic study in 51 affected subjects and 102 normals matched for age and sex. Prevalence of mitral valve prolapse was 25% in patients with systemic lupus erythematosus and 9% in healthy controls with a statistically significant difference (p less than 0.01). Neither pericardial effusion nor prolonged (more than 12 months) treatment with corticosteroids were associated with higher prevalence of mitral valve prolapse. Libman-Sacks verrucae on the mitral valve apparatus as well as focal myocardial scars affecting the papillary muscles and adjacent myocardium could be responsible for the development of the valvular dysfunction. We suggest that mitral valve prolapse can be considered a manifestation of cardiac involvement in patients with systemic lupus erythematosus.