A method to avoid knot-tying in artificial chordae implantation for mitral valve repair

Background and aim of the study: Expanded polytetrafluoroethylene (ePTFE) neo-chordae implantation requires knot-tying inside the heart, which can be especially difficult if a minimally invasive approach is used. A system has been developed that allows the implantation of neo-chordae, without a need for knot-tying, in addition to a simultaneous and reversible length adjustment after the evaluation of valve continence using hydrostatic tests. Methods: The system consists of a suture with a needle at one end and a 20 mm pledgeted loop at the opposite end. The suture presents five stop-knots at constant (2 mm) intervals, starting 35 mm from the base of the loop. The suture is passed first through the leaflet, then through the papillary muscle, then inside a reversible noose-lace (cow-hitch) that is made on the loop. The noose-lace is closed under one of the knots of the suture coming from the papillary muscle. After closing the loop at a presumably optimal length, a hydrostatic test is performed. The chordal length can be modified by releasing the noose-lace and sliding it over another fixing-knot until an optimal distance is obtained. Results: Fourteen patients underwent repair with this technique. No deaths or major adverse events occurred. All patients underwent echocardiography at discharge, and again at six and 12 months after surgery. Thirteen patients had no residual insufficiency, and one patient had mild postoperative insufficiency but without progression of regurgitation at the sixth postoperative month. Conclusion: This new technique facilitates artificial chordae implantation. The short-term results are satisfactory, but further follow up is required.