P6491Predictive effect of mitral annular size on persistent mitral valve dysfunction after transcatheter edge-to-edge mitral valve repair for functional mitral regurgitation

Abstract Background In patients with functional mitral regurgitation (FMR), deformation of the mitral valve (MV) apparatus leads to deteriorating coaptation of both leaflets. The MV geometry is essential to predict procedural success of using the MitraClip™ for FMR patients. Persistent such mitral regurgitation (MR) and post-procedural mitral stenosis (MS) are parameters for an increasing mortality rate after MitraClip implantation. The anterior-to-posterior mitral annulus diameter (MAD) is simple to evaluate with a high reproducibility rate. However, the predictive effect has not been determined to date. Purpose We evaluated the predictive effect of baseline anterior-to-posterior MAD on persistent MV dysfunctions after MitraClip™ implantation. Methods We investigated the prevalence of procedural failure (MR at discharge > grade 2+) and post-procedural MS (mean transmitral gradient (mTMG) at discharge ≥6 mmHg) in a patient cohort with FMR (n=190), who underwent MitraClip™ implantation. We measured the MV apparatus geometry on mid-systole using transoesophageal echocardiography before the index procedure. The MAD was stratified by interquartile ranges (IQR) in the comparison. (≤34 mm, 35 to 37 mm, 38 to 40 mm, and ≥41 mm, respectively) Results The mean age was 75±9 years, and 63 patients (33%) were female. The mean left ventricular ejection fraction was 34±14%. Moderate-to-severe (3+) or severe MR (4+) were documented in all patients before the procedure. Transthoracic echocardiography at discharge revealed residual MR (>2+) in 10 patients (5%) and post-procedural MS in 13 patients (7%), in which one patient presented with both residual MR and MS. After stratification by the IQRs of MAD, there were significant differences in body weight (p