Durability of mitral valve repair for mitral regurgitation due to degenerative mitral valve disease.

Degenerative diseases of the mitral valve (MV) are the most common cause of mitral regurgitation in the Western world and the most suitable pathology for MV repair. Several studies have shown excellent long-term durability of MV repair for degenerative diseases. The best follow-up results are obtained with isolated prolapse of the posterior leaflet, however even with isolated prolapse of the anterior leaflet or prolapse of both leaflets the results are gratifying, particularly in young patients. The freedom from reoperation on the MV at 15 years exceeds 90% for isolated prolapse of the posterior leaflet and it is around 70-85% for prolapse of the anterior leaflet or both leaflets. The degree of degenerative change in the MV also plays a role in durability of MV repair. Most studies have used freedom from reoperation to assess durability of the repair but some studies that examined valve function late after surgery suggest that recurrent mitral regurgitation is higher than estimated by freedom from reoperation. We can conclude that MV repair for degenerative mitral regurgitation is associated with low probability of reoperation for up to two decades after surgery. However, almost one-third of the patients develop recurrent moderate or severe mitral regurgitation suggesting that surgery does not arrest the degenerative process.