Implications of mitral valve prolapse in children with rheumatic mitral regurgitation.

OBJECTIVES: This study was conducted to determine the longterm prognosis of children with mitral valve prolapse associated with isolated rheumatic mitral regurgitation.

BACKGROUND: Rheumatic fever may result in mitral valve prolapse, which sometimes leads to severe mitral regurgitation requiring surgical intervention during the active stage of rheumatic fever. However, the influence of mitral valve prolapse on the prognosis of patients with rheumatic mitral regurgitation remains largely unknown.

METHODS: From 1971 to 1991, 181 children who fulfilled the revised Jones criteria of rheumatic fever were identified from a rheumatic fever prevention program. Of the 181 patients, isolated mitral regurgitation was diagnosed in 123 at age 4 to 12 years. The diagnosis of mitral valve prolapse was based on echocardiographic findings. Actuarial event-free curves for persistent murmur, cardiac improvement and surgical intervention were drawn according to the Kaplan-Meier nonparametric estimation.

RESULTS: Evidence of mitral valve prolapse was shown in 37 (30%) of the 123 patients. Patients with mitral valve prolapse were more likely to have a larger cardiac size than those without mitral valve prolapse during the active stage of rheumatic fever. Although the cardiac status of patients with mitral valve prolapse may improve under adequate secondary prophylaxis, an actuarial analysis indicated that patients with mitral valve prolapse had a greater likelihood of murmur persistence and surgical intervention. This trend toward murmur persistence was observed even when patients with heart failure during the active stage of rheumatic fever were excluded from analysis.

CONCLUSIONS: The presence of mitral valve prolapse in children with isolated rheumatic mitral regurgitation may predict a less favorable outcome.