Transseptal chordal replacement: early experience

Abstract

Chordal replacement is a fundamental technique used in the surgical repair of primary mitral regurgitation, and can be an effective means of preserving the native valve without leaflet resection. Surgical chordal replacement can be challenging since it is performed on an open, non-beating heart, and choosing the correct chord length to restore the zone of coaptation requires both intuition and skill. Developing transcatheter, transfemoral, and transseptal approaches to mitral valve chordal replacement presents the opportunity for safer and potentially earlier treatment of patients with primary mitral regurgitation. In particular, transcatheter methods will allow adjustment of chordal length and position real-time on a beating heart under echocardiographic guidance. In this manuscript, we review the current transcatheter transseptal technologies in development and discuss the various issues related to device design, efficacy, durability, and clinical trial design.

Keywords: Mitral regurgitation; chordal replacement; transcatheter; transseptal.

Figure 1

CardioMech device. (A) Leaflet capture and chordal attachment; (B) positioning ventricular anchor; (C) ventricular anchor placed; (D) final after chordal tensioning and anchor deployment.

Figure 2

ChordArt implant. There are nitinol leaflet and papillary muscle anchors with an ePTFE chord.

Figure 3

ChoRe implant. (A) The pre-constructed knot with the polyester thread in blue and the leaflet pledget in green; (B) the artificial chord with the ePTFE thread in black and the apex pledget in yellow; (C) the apex pledget, previously positioned into the device, is pushed through the ventricle wall using a cannula to create the apex fixation. The apex pledget folds into an accordion shape due to the movement of the device from the apex to the leaflet and the interaction of the apex pledget with the ventricle wall; (D) the pre-constructed knot is pushed by the surgeon against the leaflet; (E,F) once the length is decided, the surgeon tightens the pre-constructed knot around the artificial chord to finalize the procedure; (G) sketch of the artificial chord installed in the left ventricle, the red box shows a close-up of the implant on the posterior leaflet. The red arrows represent the movements made by the surgeon while the blue arrows the tightening of the pre-constructed knot. The catheter (light blue) and the device (red) are shown only once for simplicity. Reproduced with permission from Culmone et al. (2).

Figure 4

Mitral Butterfly. (A) Transatrial delivery system; (B) mitral Butterfly device; (C) appearance of device implanted on posterior mitral leaflet.

Figure 5

Pipeline device. (A) Ventricular neo-papillary anchor (arrow) placement via transfemoral transseptal catheter with attached suture; (B) leaflet pledget placement (arrow) with attached suture into prolapsed segment. Up to three pledgeted sutures can be placed per anchor; (C) suture lock (arrow) is advanced into anchor and pledgeted suture(s) are tensioned under real time and then locked; (D,E) appearance after tensioning, locking, and cutting sutures with resolution of prolapse. Note that the top of ventricular anchor is at the same level as the native papillary muscles.

Figure 6

Valtech V-Chordal. (A) The V-Chordal device; (B) crossing of the left atrium and the MV; (C) deployment of the helical fixation anchor on the papillary muscle; (D) ePTFE chordal loop is released; (E) the new chordae are then sutured to the mitral leaflet; (F,G) final result after chordal length adjustment.

Video

Transseptal chordal replacement: early experience.