The chordae tendinae connect the papillary muscles to the mitral valve. While the first-order chordae serve to secure the leaflets to maintain valve closure and prevent mitral valve prolapse, the second-order chordae are believed that they play a role in maintaining normal LV size and geometry. The papillary muscles, from where the chordae tendinae originate, function as shock absorbers that compensate for the geometric changes of the left ventricular wall. The second-order chordae connect the PMs to both trigons under tension. The tension distributed towards the second-order chordae has been demonstrate to be more than three-fold that in the first-order counterpart. Cutting the second-order chordae puts all the tension on the first-order chordae, that can go closer to their rupture point. However, it has been experimentally demonstrated that the tension where the first-order chordae break is 6.8 N, by far higher than the maximal tension reached, that is 0.4 N. Even if the clinical reports have been favorable, the importance of cutting the second-order chordae to recover curvature of the anterior leaflet and increasing the coaptation length between the mitral leaflet has been slowly absorbed by the surgical world. Nevertheless, there are progressive demonstrations that chordal tethering affects the anterior leaflet not only in secondary, but also in primary mitral regurgitation, having a not negligeable role in the long-term outcome of mitral repair.

Mitral valve regurgitation (MR) is a common valvular disorder occurring in up to 10% of the general population. Mitral valve reconstructive strategies may address any of the components, annulus, leaflets and chords, involved in the valvular competence. The classical repair technique involves the resection of the prolapsing tissue. Chordal replacement was introduced already in the ’60, but in the mid ’80, some surgeons started to use expanded polytetrafluoroethylene (ePTFE) Gore-Tex sutures. In the last years, artificial chords have been exploited because of transcatheter techniques such as NeoChord DS 1000 (Neochord, USA) and Harpoon TSD-5. The first step is to achieve a good exposure of the papillary muscles that before approaching the implant of the artificial chords. Then, the chords are attached to the papillary muscle, with or without the use of supportive pledgets. The techniques to correctly implant artificial chords are many and might vary considerably from one center to another, but they can be summarized into three big families of suturing techniques: single, running or loop. Regardless of how to anchor to the mitral leaflet, the real challenge that many surgeons have taken on, giving rise to some very creative solutions, has been to establish an adequate length of the chords. It can be established basing on anatomically healthy chords, but it is important to bear in mind that surgeons work on the mitral valve when the heart is arrested in diastole, so this length could fail to replicate the required length in the full, beating heart. Hence, some surgeons suggested techniques to overcome this problem. Herein, we aimed to describe the current use of artificial chords in real world surgery, summarizing all the tips and tricks.

Choosing to perform mitral valve (MV) repair or replacement remains a hot and highly debated topic. The current guidelines seem to be conflicting in this specific field and the evidences at our disposal are scarce, only one small randomized trial and few larger retrospective studies. The meta-analysis by Gamal and coworkers tries to summarize the current evidences, concluding that MV replacement for the treatment of ischemic mitral regurgitation is at least as safe as repair and certainly offers a more stable result over time than the latter. Obviously, the implantation of a prosthesis, especially a mechanical one, brings with it a series of problems, such as anticoagulation and, above all, a possible lack of ventricular remodeling, especially if a chordal sparing replacement is not performed. It must be said, on the other hand, that isolated annuloplasty cannot act as a counterpart to replacement, because ischemic MR cannot be considered only an annular disease. Therefore, wanting to mimic the nature that, after an infarction, enacts a series of changes involving also the mitral leaflets and chordae, the surgeons are called to act also on these two entities and not only to downsize the annulus. In a nutshell, a procedure should not be opposed in a fundamentalist way to another one, but we must accept the concept of armamentarium where both procedures are present and tail on the single patient, and also on the surgeon’s expertise, the technique guaranteeing the best possible result.