Background: Symptomatic mitral restenosis develops in 7% to 21% of patients after percutaneous mitral balloon valvotomy (PMV). Surgical mitral valve replacement (MVR) and repeat PMV are treatment options in these patients. Previous studies indicate that redo PMV is feasible with good immediate and intermediate outcomes, but no comparisons have been made between two procedures. The purpose of this study was to compare the long-term outcome of symptomatic mitral restenosis patients after repeat PMV or MVR. Methods and results: From April 1988 to December 2003, 888 patients underwent PMV. Among them, 32 patients had repeat PMV and 59 patients were treated with MVR for symptomatic mitral restenosis. Clinical outcome (death, repeat procedure, stroke and readmission for heart failure) was retrospectively analyzed and compared between the groups. The mean follow-up period was 80.5짹41.1 months with a maximal follow-up of 15 years. Patients with MVR have more unfavorable clinical characteristics including higher incidence of atrial fibrillation and severe mitral regurgitation. Although event-free survival was comparable between two groups until 40 months after the procedure (3-year event-free survival 96.6% for MVR patients and 90.0% for redo PMV patients, p=0.215), more favorable outcome for MVR versus redo PMV was noted after 40 months (6-year event-free survival 92.9 vs 75.1%, p=0.033; 9-year event-free survival 89.2 vs 40.1%, p=0.003). Conclusion: In this retrospective study, symptomatic mitral restenosis patients after prior PMV had better long-term event-free survival after MVR than after redo PMV. These data suggest MVR may be the preferred mode of therapy in patients with restenosis after previous PMV who are expecting extended benefit from the procedure.