Chordal replacement: future surgical gold standard or first-line option as bridge to definitive therapy in primary mitral regurgitation?

Transapical mitral valve repair procedures: Primetime for microinvasive mitral valve surgery

INTRODUCTION

Nowadays micro-invasive-procedures (off-pump, beating-heart) for mitral valve repair (MVRe) are abruptly expanding with the potential to be adopted as a valuable alternative to surgery. In the present manuscript, the authors review the available technologies intended to treat mitral regurgitation (MR) through transapical approach, including annuloplasty and chordal-repair options.

ANNULOPLASTY

To date, Valcare Amend is the only transapical MV ring to have been implanted in patients. The device allows for stabilization of the annulus through a complete semirigid d-shaped ring. The first-in-human successful procedure was performed in 2016 by our Group and subsequent clinical experience included a total of 14 implanted patients. Currently, the technology is under clinical trial evaluation to validate the efficacy and safety profile of the device.

CHORDAL REPAIR

Beating-heart chordal implantation via transapical approach is a current feasible, safe and reproducible option. Neochord DS1000 is the most widely used technology in the field, with a solid procedural experience and good results in well-selected patients. Its clinical use has been validated in Europe since 2012, while it is still under clinical investigation in the United States. Harpoon MVRe system is a novel technology, recently CE-mark approved for clinical use.

DISCUSSION AND CONCLUSIONS

Transapical micro-invasive technologies are current viable therapies to treat MR in selected patients. Although there are still several limitations that preclude an extensive use of such procedures, their results are promising in well-selected patients. Embracing transcatheter MVRe therapies should guide the cardiac surgeon through the new revolution of micro-invasive MV tailored repair.

State-of-the-Art Review: Technical and Imaging Considerations in Novel Transapical and Port-Access Mitral Valve Chordal Repair for Degenerative Mitral Regurgitation

Degenerative mitral regurgitation (DMR) based on posterior leaflet prolapse is the most frequent type of organic mitral valve disease and has proven to be durably repairable in most cases by chordal repair techniques either by conventional median sternotomy or by less invasive approaches both utilizing extracorporeal circulation and cardioplegic myocardial arrest. Recently, several novel transapical chordal repair techniques specifically targeting the posterior leaflet have been developed as a far less invasive and beating heart (off-pump) alternative to port-access mitral repair. In order to perform a safe and effective minimally invasive mitral chordal repair, thorough knowledge of the anatomy of the mitral valve apparatus and adequate use of multimodality imaging both pre- and intraoperatively are fundamental. In addition, comprehensive understanding of the available novel devices, their delivery systems and the individual procedural steps are required.

Mitral valve repair with a device for artificial chordal implantation at 2 years

Objectives

This study examines the early and midterm safety, efficacy, and durability of mitral valve repair for primary mitral regurgitation (MR) using the ChordArt device (CoreMedic) for chordal replacement.

Methods

Five patients with symptomatic severe primary degenerative MR due to isolated central posterior leaflet prolapse/flail were treated with the ChordArt device in a transseptal surgical approach and followed prospectively with periodical clinical and echocardiographic assessments for 2 years.

Results

Reduction of MR immediately after the implantation of artificial chords was achieved in all patients showing no or trace MR (<1+/4+). In all patients, MR <1+ was maintained during 24 months of follow-up. No dehiscence, detachment, or dislocation of the implanted ChordArt devices was observed. Transthoracic echocardiography showed that left ventricle end diastolic diameter significantly decreased during the whole follow-up period in comparison to baseline condition, especially at discharge and 1-month follow-up. Left ventricle end systolic diameter also significantly decreased during the whole follow-up period in comparison to baseline condition. Left atrial volume significantly decreased during the follow-up period in comparison to discharge. No major adverse events, as defined per protocol, were observed during the intervention or during the follow-up period.

Conclusions

The ChordArt device allows successful treatment of primary degenerative MR due to posterior mitral leaflet prolapse or flail, with a good safety profile and promising immediate clinical and echocardiographic benefits that are confirmed up to 24 months.