Hemodynamic Comparison of Mitral Valve Repair: Techniques for a Flail Anterior Leaflet

Background and aim of the study: Anterior leaflet flail resulting from elongated or ruptured marginal chordae is frequently diagnosed among adults, and is amenable to surgical repair. The study aim was to investigate the efficacy of three surgical techniques, namely neochordoplasty, limited triangular resection and edge-to-edge repair, to correct anterior leaflet flail in an in-vitro experimental model. Methods: Seven porcine mitral valves were evaluated in a pulsatile heart simulator before surgical manipulation, after anterior marginal chordae transection, and with each surgical repair. Marginal chordal transection induced leaflet flail with moderate mitral regurgitation (MR). Following the confirmation of MR via direct flow measurements, it was corrected by three repairs: neochordoplasty with ePTFE sutures, limited triangular resection, and edge-to-edge repair. The post-repair valve hemodynamics were quantified under pulsatile conditions of 120 mmHg peak transmitral pressure and 5 1/min cardiac output at 70 beats/min. Hemodynamic, geometric and echocardiographic indices were also measured. Results: Transecting the marginal chordae induced A2 prolapse and produced the regurgitant fraction to 18.7 +/- 10.2%. Surgical repair effectively reduced the regurgitant fraction to 6.9 +/- 6.3% (p = 0.019 to prolapse, p = 0.0117 to baseline) with neochordae, to 5.8 +/- 7.0% (p = 0.03 to prolapse, p = 0.0378 to baseline) with triangular resection, and to 13.3 +/- 10.2% (p = 0.2091 to prolapse, p = 0.0045 to baseline) with edge-to-edge repair. Remnant regurgitation was largest with edge-to-edge repair compared to limited leaflet resection and neochordoplasty, though central leaflet coaptation was restored equally by the three repairs, with mild systolic leaflet restriction after repair. Conclusion: Anterior leaflet repair and a reduction in MR is achievable with the three techniques, although neochordoplasty and triangular resection proved superior to edge-to-edge repair in eliminating MR.