Chordae replacement versus leaflet resection in minimally invasive mitral valve repair

Abstract

For many years, the quadrangular resection technique first proposed by Carpentier has become the gold standard for repair of posterior leaflet prolapse of the mitral valve (MV). Although this "resection" technique and its modifications are safe and very effective, they do not respect the anatomy of the MV and the physiological role of the posterior leaflet. Therefore some new techniques, aiming to preserve MV leaflets to a different extent, have been proposed. With the use of expanded polytetrafluoroethylene (ePTFE), neochordae leaflet preserving techniques for posterior MV prolapse treatment have emerged. The aim of these techniques is to support the free edge of the prolapsing segments and thereby restore the physiologic function of the MV. A simplified modification of this technique using premeasured ePTFE loops ("loop technique") was successfully introduced to ease the implantation of neochordae, especially in the setting of minimally invasive MV surgery. While "resection" techniques are associated with excellent long-term results, there is evolving evidence in favor of "non-resection" techniques supporting the concept of a "respect rather than resect" approach.

Keywords: Mitral valve repair (MVR); chordae replacement; leaflet prolapse; leaflet resection; loop technique; minimally invasive mitral surgery.

Figure 1

Scheme showing evolution of mitral valve repair techniques: from extensive tissue resection represented by quadrangular resection through limited tissue resection to finally no resection in chordae replacement.

Figure 2

Illustrations showing “resection technique” of mitral valve repair represented by triangular resection. (A) Degenerative mitral valve disease with posterior leaflet prolapse (P2—posterior middle scallop); (B) Dashed line represents the resection area of posterior leaflet; (C) Reconstructed posterior leaflet after triangular resection; (D) Completed repair accomplished by prosthetic ring annuloplasty; Notice smaller ring implanted in this technique and smaller surface of coaptation (detailed image).

Figure 3

Illustrations showing “respect rather than resect technique” of mitral valve repair represented by chordal replacement with ePTFE “loop technique”. (A) Degenerative mitral valve disease with posterior leaflet prolapse (P2—posterior middle scallop); (B) Premade ePTFE loops are attached to the fibrous tip of the papillary muscle; (C) Individual loops are attached to the prolapsing segment margin of posterior leaflet; (D) Completed repair accomplished by prosthetic ring annuloplasty. Notice larger ring implanted in this technique and larger surface of coaptation (detailed image).