Is prosthetic anuloplasty necessary for durable mitral valve repair?

BACKGROUND: Because emerging percutaneous mitral valve repair may address only leaflets and not the anulus, we compared durability of mitral valve repair with and without prosthetic anuloplasty.
METHODS: From 1985 to 2007, 3,057 patients underwent primary isolated posterior leaflet repair for degenerative mitral disease either with prosthetic anuloplasty (n = 2,754, 90%) or without (n = 303, 9.9%: no anuloplasty, 68; suture anuloplasty, 7; pericardial anuloplasty, 228). Most of the latter operations occurred in the early 1990s. Differences in patient characteristics were addressed by propensity-score adjustment and matching (214 pairs). In all, 3,870 echocardiograms for 1,236 patients were available for assessing mitral regurgitation after prosthetic anuloplasty and 257 in 99 patients without one. Mean follow-up for mitral valve reoperation was 4.2 +/- 4.1 years, with 13,003 patient-years of data available for analysis.
RESULTS: Early, and to a lesser degree late, postoperative mitral regurgitation was less after prosthetic anuloplasty than repair without one, and this difference persisted after risk adjustment and in propensity-matched patients (p = 0.0002). Freedom from mitral valve reoperation was 96% and 94% at 10 years after repair with versus without prosthetic anuloplasty in unmatched groups, and 97% and 96% in matched groups (p = 0.3), respectively. Unadjusted survival was greater with than without prosthetic anuloplasty (84% versus 81% at 10 years, p = 0.009), but similar after propensity adjustment and in matched pairs.
CONCLUSIONS: Mitral valve repair without a prosthetic anuloplasty was associated with accelerated return of mitral regurgitation, although risk-adjusted survival was similar. This finding has important implications for durability of percutaneous mitral repair techniques that do not address both leaflets and anulus.