P1560 Acute changes of mitral annular dimensions after transcatheter egde-to-edge repair: an indirect annuloplasty method?

Abstract

Abstract Background Percutaneous edge-to-edge mitral valve repair (PMVR) is a safe and alternative method for treating high-risk patients with severe mitral regurgitation (DMR or FMR). This transcatheter treatment aims at reducing the MR with a so-called "Alfieri stitch" method. However the impact on mitral annular dimensions after the device implantation is not well defined. The purpose of this study is to recognize the acute changes of mitral annular dimensions after transcatheter edge-to-edge repair. Methods We retrospectively analyzed 20 consecutive patients (aged 74 ± 10yrs) with degenerative or functional moderate-to-severe and severe mitral regurgitation (EROA 40.8 ± 20.5mm2, RV 52.6 ± 17.5ml) and reduced ejection fraction (EF 36.9 ± 15.4%). These patients were at high surgical risk or even inoperable in certain cases (logistic EuroSCORE 28.9 ± 18.2%) and evaluated by a heart team as candidates for transcatheter repair. All intraoperative transoesophageal echo studies were post processed with EchoPac v.203 or QLAB 9.0. 3D views of the mitral valve before and after the implantation of the device were analyzed with 4D AutoMVQ (GE) or MVQ (Phillips) software. Results PMVR was effective in treating the MR at the end of the operation (from 3.8 ± 0.4 to 1.3 ± 0.5 after the implantation, p < 0.05) in all patients. There was a significant reduction of the annulus area (from 12.25 ± 3.0cm2 to 10.18 ± 2.88cm2, p < 0.001) and circumference (from 13.23 ± 1.4cm to 12.18 ± 1.57cm, p < 0.001), in both DMR and FMR cases. The percentage reduction of annulus area and circumference after PMVR was 17.3 ± 0.8% and 8 ± 5% respectively and the number of the clips used for that purpose were 1.55 ± 0.6. Additionally, edge-to-edge repair significantly reduced the anterior-posterior diameter (from 3.49 ± 0.56cm to 3.02 ± 0.55cm, r = 0.86, p < 0.001) and the posteromedial-anterolateral diameter (from 4.15 ± 0.58cm to 3.88 ± 0.60cm, r = 0.9, p < 0.001). The number of the clips used did not play an important role in the percentage difference of the annulus dimensions (20% reduction with one clip vs 14.3 ± 7.6% with two or more, p < 0.05) and one possible explanation could be that patients receiving one clip had smaller annulus area comparing to the patients receiving two or more (11.2 ± 2.9mm2 vs 13.3 ± 2.7mm2 respectively, p < 0.05). Conclusions Transcatheter edge-to-edge repair is effective in treating MR in patients with DMR and FMR and has a direct impact on mitral annular dimensions acutely after the implantation.