Two patients in our institution underwent mitral valve reconstruction during the acute phase of Staphylococcus aureus mitral valve endocarditis. In neither case was a pre-existing valve lesion found. Echocardiographic examination revealed severe mitral insufficiency and the extent of valvular lesions. In the first patient, prolapse of the posterior commissure and paracommissural areas was due to ruptured chordae tendinae. In the second patient a perforated abscess was surrounded by vegetations in the median portion of the anterior leaflet and paramedian anterior chordae tendinae were ruptured. The surgical indication was hemodynamic, combined with suspicion of repeated emboli in one case. After a 10-day course of antibiotic therapy, both patients underwent surgical repair by Carpentier's mitral valvuloplasty. During more than 6 months' follow-up no recurrence of endocarditis was observed. Both patients were in class I of the NYHA without echocardiographic evidence of residual mitral regurgitation or stenosis. Early intervention during the acute phase of endocarditis, when mitral valve destruction is not too extensive, allows mitral valvuloplasty which preserves the native valve, eradicates infected tissues and may reduce postoperative mortality and morbidity.