[Repair of mitral regurgitation caused by prolapse of the anterior mitral leaflet].

Mitral regurgitation caused by prolapse of the anterior mitral leafleft has been considered to be difficult for reconstruction. In Japan, these cases have been repaired mainly by replacement of chordae with artificial sutures. We have repaired them by Carpentier's technique. We report a series of 9 patients with pure mitral regurgitation caused by ruptured or elongated chordae of the anterior mitral leaflet. Two of them had lesions at both anterior and posterior leaflet. All patients underwent mitral valve repair by segmental transposition of the posterior leaflet. As for associated procedures, there were ring annuloplasty with Carpenter rings (9 cases), sliding technique (8 cases) reported by Carpentier, reinforcement by transposition of secondary chordae of the posterior leaflet (6 cases), commissuroplasty (1 case), and closure of leaflet perforation. All patients survived operations and all patients except one underwent left ventriculography postoperatively. In only 2 patients, residual mitral regurgitation classed as I/IV was observed. All patients returned home in New York Heart Association class I. Follow-up ranged from 7 to 45 months (mean follow-up 20 months). All patients were free from reoperation or thromboembolism. Although longer follow-up is necessary, this technique appears to be adequate for the repair of patients with anterior leaflet prolapse.