What Is the Optimal Mitral Valve Repair for Isolated Posterior Leaflet Prolapse to Achieve Long-Term Durability?

Background This study assessed risk factors for mitral regurgitation (MR) recurrence or functional mitral stenosis during long-term follow-up in patients undergoing mitral valve repair for isolated posterior mitral leaflet prolapse. Methods and Results We assessed a consecutive series of 511 patients who underwent primary mitral valve repair for isolated posterior leaflet prolapse between 2001 and 2021. Annuloplasty using a partial band was selected in 86.3%. The leaflet resection technique was used in 83.0%, whereas the chordal replacement without resection was used in 14.5%. Risk factors were analyzed for MR recurrence ≥grade 2 or functional mitral stenosis with mean transmitral pressure gradient ≥5 mm Hg using a multivariable Fine-Gray regression model. The 1-, 5-, and 10-year cumulative incidence of MR ≥grade 2 was 7.8%, 22.7%, and 30.1%, respectively, whereas that of mean transmitral pressure gradient ≥5 mm Hg was 8.1%, 20.6%, and 29.3%, respectively. Risk factors for MR ≥grade 2 included chordal replacement without resection (hazard ratio [HR], 2.50, <0.001) and larger prosthesis size (HR, 1.13, =0.023), whereas factors for functional mitral stenosis were use of a full ring (partial band versus full ring, HR, 0.53, =0.013), smaller prosthesis size (HR, 0.74, <0.001), and larger body surface area (HR, 3.03, =0.045). Both MR ≥grade 2 and mean transmitral pressure gradient ≥5 mm Hg at 1 year post surgery were significantly associated with the long-term incidence of reoperation. Conclusions Leaflet resection with a large partial band may be an optimal strategy for isolated posterior mitral valve prolapse.