Mitral valve repair for degenerative disease.

Degenerative mitral valve disease is the most common cause of mitral regurgitation in North America. Using techniques developed by Carpentier and others, up to 90% of degenerative mitral valves can be repaired. These valves are characterized by annular dilatation and chordal rupture or elongation; chordal changes are mainly localized to the posterior leaflet. The most common repair technique for posterior leaflet prolapse is quadrangular resection. When the leaflet is >1.5 cm long, a sliding repair is added to reduce the risk of systolic anterior motion. Anterior leaflet prolapse is usually treated by transfer of chords from the posterior leaflet or adjacent areas of the anterior leaflet. Other useful techniques for correction of anterior leaflet prolapse are creation of artificial chords and the Alfieri edge-to-edge repair. Chordal shortening is rarely employed as it jeopardizes repair durability. Annuloplasty accompanies all repairs. A posterior annuloplasty provides results equivalent to those obtained with a circumferential annuloplasty. Flexible annuloplasty has theoretical advantages, but clinical benefits have not been shown. After mitral valve repair for degenerative disease, 10-year freedom from reoperation is 93%. Risk of reoperation is increased by anterior leaflet prolapse, chordal shortening, failure to use an annuloplasty, and lack of intraoperative echocardiography. In the ideal situation, when posterior leaflet resection is corrected by quadrangular resection with annuloplasty and the result is confirmed by intraoperative echocardiography, the 10-year durability is 98%.