A simple method of preparing artificial chordae for mitral valve repair

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.

Intermediate-term outcomes of our original multiple-knot technique using ePTFE sutures for anterior mitral leaflet prolapse

PURPOSE

To define the outcomes of our original simple chordal replacement technique using ePTFE sutures for mitral regurgitation.

METHODS

Between January, 2004 and March, 2014, 38 patients underwent mitral valve repair using our chordal replacement technique for anterior leaflet prolapse. The mitral regurgitation was caused by degenerative disease in 34 patients and infective endocarditis in 4 patients.

RESULTS

The follow-up period was 66 ± 37 months and the 5-year survival rate was 95 ± 4%. Two patients had recurrent mitral regurgitation, caused by degenerative change not associated with the procedure. The 5-year rate of freedom from recurrent mitral regurgitation was 94 ± 4%. In the late postoperative period, 15 (42%) patients had a mean pressure gradient > 5 mmHg. Stepwise logistic regression analysis showed that the use of a full ring (odds ratio 8.9; 95% confidence interval 1.2-64; p = 0.031) and a 26 mm annuloplasty (odds ratio 7.5; 95% confidence interval 1.1-50; p = 0.037) were significant independent risk factors for a mean pressure gradient > 5 mmHg.

CONCLUSION

The intermediate-term outcomes of our original chordal replacement technique were not inferior to those in previous reports, although a 26 mm annuloplasty was found to be associated with a higher mitral valve gradient at rest.

Neochordameter: a new technology in mitral valve repair

BACKGROUND

Mitral valve repair has shown superior results compared to mitral valve replacement in patients with mitral valve prolapse. Using premeasured neochordae (the loop technique) has been proposed for both anterior and posterior leaflet repairs. However, there are two major problems that are usually experienced using this method. One is deciding the length of the neo-chordae, and the other is tying the knot at the intended length.

OBJECTIVES

This study introduced a new technology in mitral valve repair that reduces the complexity of making neo-chordae loops, especially in minimally invasive surgeries.

PATIENTS AND METHODS

Neochordameter is a new device which utilizes preoperative transthoracic echocardiography to determine the exact length of required neochordae and enable surgeons to make neochordae loops before starting the cardiopulmonary bypass. In this study, we applied this technique in mitral valve repair of three patients.

RESULTS

Two of these patients were male and the other one was female. All of them had severe mitral regurgitation requiring anterior leaflet repair. Total eight neochordae loops were used in these patients. No change in the length of neochordae was required after saline test and all of these patients had none or trivial mitral regurgitation by intraoperative and follow up transesophageal echocardiography. No complication was seen in six-month follow up.

CONCLUSIONS

The ability of this technology in developing premeasured neo-chordae loops with accurate sizes and not needing the post-implantation length adjustment which is efficient in reducing the complexity of both minimally invasive and conventional surgeries are the issues which is going to be regarded .

Loop technique for mitral valve repair

A new artificial chordal reconstruction technique has been developed using several expanded polytetrafluoroethylene (ePTFE) loops. This technique differs from conventional artificial chordal reconstruction in the use of premeasured ePTFE loops. The loop technique involves several steps: (1) assessment of the corresponding papillary muscle; (2) measurement of the required ePTFE loop length; (3) making a loop set of the premeasured length; (4) anchoring the loop set to the papillary muscle; (5) fixing the ePTFE loops to the prolapsing leaflet; (6) adjusting the loop length if necessary; and (7) ring implantation. Favorable early and mid-term results of this loop technique have been reported in patients undergoing mitral valve repair through mini-thoracotomy and via median sternotomy, with 3-year survival and re-operation-free rates of 94.8 and 97.4 %, respectively. The loop technique using ePTFE chordal reconstruction with premeasured loops thus appears to be a safe, reliable, and reproducible technique for mitral valve repair. In addition, it is suitable for both minimally invasive and conventional sternotomy approaches, and represents a useful technique for treating posterior, anterior, and especially bi-leaflet prolapses.

Artificial chordae for degenerative mitral valve disease: critical analysis of current techniques

The surgical repair of degenerative mitral valve disease involves a number of technical points of importance. The use of artificial chordae for the repair of degenerative disease has increased as a part of the move from mitral valve replacement to repair of the mitral valve. The use of artificial chordae provides an alternative to the techniques pioneered by Carpentier (including the quadrangular resection, transfer of native chordae and papillary muscle shortening/plasty), which can be more technically difficult. Despite a growth in their uptake and the indications for their use, a number of challenges remain for the use of artificial chordae in mitral valve repair, particularly in the determination of the correct length to ensure optimal leaflet coaptation. Here, we analyse over 40 techniques described for artificial chordae mitral valve repair in the setting of degenerative disease.

Mitral valve repair under cardiopulmonary bypass in small-breed dogs: 48 cases (2006-2009)

OBJECTIVE

To determine whether mitral valve repair (MVR) under cardiopulmonary bypass would be an effective treatment for mitral regurgitation in small-breed dogs.

DESIGN

Retrospective case series.

ANIMALS

48 small-breed dogs (body weight, 1.88 to 4.65 kg [4.11 to 10.25 lb]; age, 5 to 15 years) with mitral regurgitation that underwent surgery between August 2006 and August 2009.

PROCEDURES

Cardiopulmonary bypass was performed with a cardiopulmonary bypass circuit. After induction of cardiac arrest, a mitral annuloplasty was performed, and the chordae tendineae were replaced with expanded polytetrafluoroethylene chordal prostheses. After closure of the left atrium and declamping to restart the heart, the thorax was closed.

RESULTS

Preoperatively, cardiac murmur was grade 3 of 6 to 6 of 6, thoracic radiography showed cardiac enlargement (median vertebral heart size, 12.0 vertebrae; range, 9.5 to 14.5 vertebrae), and echocardiography showed severe mitral regurgitation and left atrial enlargement (median left atrium-to-aortic root ratio, 2.6; range, 1.7 to 4.0). 45 of 48 dogs survived to discharge. Three months after surgery, cardiac murmur grade was reduced to 0/6 to 3/6, and the heart shadow was reduced (median vertebral heart size, 11.1 vertebrae, range, 9.2 to 13.0 vertebrae) on thoracic radiographs. Echocardiography confirmed a marked reduction in mitral regurgitation and left atrium-to-aortic root ratio (median, 1.7; range, 1.0 to 3.0).

CONCLUSIONS AND CLINICAL RELEVANCE

We successfully performed MVR under cardiopulmonary bypass in small-breed dogs, suggesting this may be an effective surgical treatment for dogs with mitral regurgitation. Mitral valve repair with cardiopulmonary bypass can be beneficial for the treatment of mitral regurgitation in small-breed dogs.

Different ways to repair the mitral valve with artificial chordae: a systematic review

Myxomatous mitral regurgitation (type II Carpentier's functional classification) affects about 1-2% of the population. This represents a very common indication for valve surgery resulting in a low percentage of repairs compared to replacement which is actually performed. In the last decades, several methods for mitral valve repair have been developed, to make the surgical feasibility easier, improve the long-term follow-up thus avoiding the need for reoperations. A very interesting method is represented by the combination of various valve repair techniques, depending on the involvement of the anterior, posterior, or both leaflets, and the use of PTFE artificial chordae tendineae when excessive chordal elongation or rupture due to myxomatous degeneration co-exists. The aim of this review is to summarize the evolution of these techniques from the beginning till now.

A simple method of making artificial chordal loops for mitral valve repair

Artificial chordal replacement with expanded polytetrafluoroethylene is an established technique for mitral valve repair. This report describes a simple technique of using Hegar dilators for making premeasured artificial chordal loops, whether as a single set of loops or as two connected sets of loops arising from the same stem. This technique uses a simple and widely available tool, the Hegar dilator, for preparation of chordal loops and further establishes the repair of opposing two segments of mitral valve by securing only one stem of the neochordae to the papillary muscle.

Intracardiac calipers for artificial chordae replacement in mitral valve repair

Length adjustment of artificial chordae is crucial in the outcome of anterior mitral valve repair. Herein, a simple and reproducible method of artificial chordal replacement using polytetrafluoroethylene suture is described. With this technique, the length of the neo-chordae is easily decided and the knot can be tied surely without change in the length using only one instrument.