Evaluating the feasibility of a novel device for enhanced control of chordal length assessment in mitral valve surgery: A porcine model study.

OBJECTIVE

Determining the appropriate expanded polytetrafluoroethylene (ePTFE) chord length remains a critical step in mitral valve repair. Freehand ePTFE suturing and premeasured loops are widely used but present technical challenges. A novel chordal holder device was developed to temporarily secure the ePTFE suture during pressurized saline infusion testing, enabling precise subsequent adjustment of chordal length. This feasibility study evaluated this technology in an ex vivo porcine heart model.

METHODS

In 20 ex vivo porcine hearts, Carpentier type II mitral regurgitation was induced by cutting chordae tendineae in the A2 and/or P2 segments. An LS-5 ePTFE suture was placed using the Mi-STITCH Device. The study technology temporarily held the ePTFE suture at a desired length during infusion testing. Once optimal coaptation was achieved, the chord was permanently secured with a customized Mi-KNOT titanium fastener. Times for suture placement, length adjustment, knot fixation, and total implantation were recorded.

RESULTS

A total of 37 ePTFE sutures were implanted. The chordal holder provided reliable temporary fixation and facilitated readjustment with no suture damage. Median time for valve repair was 3 minutes, 20 seconds (02:21; 5:14), with 1 to 4 ePTFE suture placements required to achieve adequate repair. Procedural times did not differ between isolated and nonisolated P2 prolapse (P = .8265). Final infusion testing showed no residual mitral regurgitation greater than trace in all specimens.

CONCLUSIONS

Setting appropriate replacement chordal length with the evaluated technology is fast, feasible, and intuitive. The chordal holder enabled precise length adjustment and competent repairs. These encouraging results support further evaluation in clinical settings.