Mitral valve repair with artificial chords: Tips and tricks.

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 used also using transcatheter approach such as NeoChord DS 1000 (Neochord) 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 based 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.

Cutting the second order chords during mitral valve repair.

The chordae tendinae connect the papillary muscles (PMs) 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 to play a role in maintaining normal left ventricle size and geometry. The PMs, 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 threefold that in their first-order counterpart. Cutting the second-order chordae puts all the tension on the first-order chordae, which are then closer to their rupture point. However, it has been experimentally demonstrated that the tension at which the first-order chordae break is 6.8 newtons (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 increase the coaptation length between the mitral valve leaflets 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 negligible role in the long-term outcome of mitral repair.

Mitral valve repair or replacement. How long is this feud to last?

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 evidence 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 evidence, concluding that MV replacement for the treatment of ischemic mitral regurgitation (MR) 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 expertize, the technique guaranteeing the best possible result.

Recombinant activated factor VII is associated with postoperative thromboembolic adverse events in bleeding after coronary surgery.

OBJECTIVES: To evaluate the impact of recombinant activated factor VII (rFVIIa) administration on thromboembolic adverse events (TAEs) in coronary artery bypass grafting (CABG) surgery patients showing postoperative bleeding. METHODS: From January 2004 to May 2015, 180 CABG surgery patients with postoperative bleeding were included in the study. All patients were managed conservatively and 81 (45%) also received rFVIIa. RESULTS: Ten patients developed new TAEs (5.6%), 15 (8.3%) were re-explored, 4 (2.2%) had postoperative dialysis and 6 (3.3%) died by day 30 postoperation. Among those with TAEs, 7 experienced cerebrovascular accidents, 2 had myocardial infarction and 1 had pulmonary embolism. A multivariable regression model confirmed rFVIIa as the only independent factor associated with the development of TAEs (odds ratio 6.19, 95% confidence interval 1.197-31.996; P = 0.0296). Fifteen (8.3%) patients were re-explored for bleeding according to our management protocol. No variables to predict the need for re-exploration were identified by the regression model. Chest tube output was statistically significantly lower in patients who received rFVIIa from 3 h [1.9 (Q1-Q3 1.7-2.1) ml/kg/h vs 3.2 (Q1-Q3 3-3.4) ml/kg/h, P = 0.000] through to 12 h after admission [0.6 (Q1-Q3 0.5-0.6) ml/kg/h vs 0.7 (Q1-Q3 0.6-0.9) ml/kg/h, P = 0.000]. CONCLUSIONS: rFVIIa for the treatment of post-CABG bleeding resulted in increased incidence of TAEs in spite of rapid control of bleeding. Hence, rFVIIa should only be used for selected patients and with extreme caution.