Devices for transcatheter mitral valve repair: current technology and a glimpse into the future

ABSTRACT

Introduction: Due to a large unmet need for the treatment of mitral regurgitation, transcatheter mitral valve repair devices have emerged in the last decade as an alternative therapeutic option. Given the complexity of this disease, several device systems for transcatheter mitral valve repair have been developed and are categorized according to its mechanism of action; each device has advantages and disadvantages for certain clinical and pathophysiologic characteristics, and in order to improve outcomes, proper patient selection among other key points are fundamental.

Areas covered: The purpose of this article is to review the current state-of-the-art technologies available for transcatheter mitral valve repair, patient suitability, outcomes, and future perspectives.

Expert opinion: Transcatheter therapy for mitral regurgitation improves outcomes and pushes the boundaries of biomedical technology while maintaining scientific rigor for device development. Surgical and percutaneous procedures should be viewed as complements to treat a wider spectrum of patients affected by this entity. Future directions from multidisciplinary innovation and cooperation will consolidate this therapeutic option.

KEYWORDS:

• Mitral
• regurgitation
• repair
• transcatheter
• surgery
• device

Abbreviations

CE: European Conformity/Conformité Européenne; CS: Coronary sinus; CT: Computed tomography; DMR: Degenerative mitral regurgitation; ePTFE: Expanded polytetrafluoroethylene suture; FDA: Food & Drug Administration; FMR: Functional mitral regurgitation; Fr: French size; G4: MitraClip fourth generation; LA: Left atrium; LV: Left ventricle; MR: Mitral regurgitation; MV: Mitral valve; MVr: Mitral valve repair; NYHA: New York Heart Association; TMVr: Transcatheter mitral valve repair.

Article highlights

1. MR is one of the most frequent valve diseases in developed countries with an increasing incidence and poor prognosis.

2. MR is classified as primary and secondary; it is essential to distinguish between each one, because they pose different prognosis and management.

3. Although the prevalence of MR is increasing, half of the patients with primary MR and more than half of those with secondary MR do not undergo surgery. In the first case, the main reason is in high surgical risk precluding for intervention; in the second one, is the lack of a clear benefit from surgical treatment.

4. Given the multiple mechanisms for MR, specific transcatheter devices have been developed to address those anomalies: 1) leaflet approximation; 2) annuloplasty devices; 3) chordal implantation; and 4) LV remodeling devices.

5. Proper patient selection is the key to improve outcomes. Basal status, quality of life, frailty, potential risks and expected benefits of intervention as well as specific anatomical characteristics and institutional experience with certain devices should be taken into account prior to intervention.

6. In primary MR, the benchmark established by surgical MVr is high; nonetheless, TMVr devices have demonstrated safety, efficacy, and acceptable results at mid-term follow up.

7. In secondary MR, TMVr with the MitraClip system has demonstrated an improvement in survival, symptoms, and reduction of heart failure hospitalizations in properly selected symptomatic patients despite optimal medical therapy.

8. Future directions for TMVr technology will focus on the development of new devices and imaging techniques, optimizing patient selection, comparison, or combination between devices, exploring new indications, and the consolidation of comprehensive TMVr centers.

Declaration of interest

M Taramasso is a consultant for Abbott Vascular, Boston Scientific, and 4tech; and has received fees from Edwards Lifesciences, CoreMedic, Swissvortex, and Mitraltech. D Perez-Camargo has received a grant from the Spanish Society for Cardiovascular and Endovascular Surgery (B-05-2019). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was not funded.