Left ventricular geometry predicts optimal response to percutaneous mitral repair via MitraClip: Integrated assessment by two‐ and three‐dimensional echocardiography

Abstract

Objectives: To assess impact of left ventricular (LV) chamber remodeling on MitraClip (MClp) response. Background: MitraClip (MClp) is the sole percutaneous therapy approved for mitral regurgitation (MR) but response varies. LV dilation affects mitral coaptation; determinants of MClp response are uncertain. Methods: LV and mitral geometry were quantified on pre- and post-procedure two-dimensional (2D) transthoracic echocardiography (TTE) and intra-procedural three-dimensional (3D) transesophageal echocardiography (TEE). Optimal MClp response was defined as ≤mild MR at early (1-6 month) follow-up. Results: 67 degenerative MR patients underwent MClp: Whereas MR decreased ≥1 grade in 94%, 39% of patients had optimal response (≤mild MR). Responders had smaller pre-procedural LV end-diastolic volume (94±24 vs. 109±25 ml/m2, p=0.02), paralleling smaller annular diameter (3.1±0.4 vs. 3.5±0.5 cm, p=0.002), and inter-papillary distance (2.2±0.7 vs. 2.5±0.6 cm, p=0.04). 3D TEE-derived annular area correlated with 2D TTE (r=0.59, p<0.001) and was smaller among optimal responders (12.8±2.1 cm2 vs. 16.8±4.4 cm2, p=0.001). Both 2D and 3D mitral annular size yielded good diagnostic performance for optimal MClp response (AUC 0.73-0.84, p<0.01). In multivariate analysis, sub-optimal MClp response was associated with LV end-diastolic diameter (OR 3.10 per-cm [1.26 – 7.62], p=0.01) independent of LA size (1.10 per-cm2 [1.02 - 1.19], p=0.01); substitution of mitral annular diameter for LV size yielded an independent association with MClp response (4.06 per-cm2 [1.03 - 15.96], p=0.045). Conclusions: Among degenerative MR patients undergoing MClp, LV and mitral annular dilation augment risk for residual or recurrent MR, supporting the concept that MClp therapeutic response is linked to sub-valvular remodeling.

Impact of left atrial diameter on outcome in patients undergoing edge‐to‐edge mitral valve repair: results from the German TRAnscatheter Mitral valve Interventions (TRAMI) registry

“…Furthermore, recent evidence shows that isolated atrial dilatation in the context of permanent atrial fibrillation and heart failure with preserved ejection fraction might itself cause secondary MR. Due to the distinct patho‐morphology of MR in atrial remodelling, technical amenability for TMVR might be different from MR resulting from ventricular remodelling, and efficacy of TMVR in these patients has not been examined . Finally, LA enlargement might affect procedural handling of the device and technical efficacy due to distorted septum to mitral valve relation . On the other hand, very small left atria might also impair handling of the device during manoeuvring and grasping.…”

Transcatheter MitraClip repair alters mitral annular geometry – device induced annular remodeling on three-dimensional echocardiography predicts therapeutic response

“…LV chamber size was over 25% larger in MITRA-FR vs. COAPT patients, paralleling a > 3-fold increase in recurrent severe MR: MITRA-FR reported MitraClip to have no impact on outcomes, whereas MR reduction in COAPT was accompanied by heart failure and mortality benefit. As further evidence of the importance of LV remodeling as a determinant of MitraClip response, prior research from our group (encompassing 67 patients included in the current cohort) showed increased LV size to be associated with risk for sub-optimal MitraClip response (>mild MR): [5] However, the relative utility of 2D and 3D derived mitral annular size independent of LV chamber volume, impact of the device on annular remodeling, as well as intra-procedural annular remodeling as a determinant of therapeutic response were not tested – providing key rationales for the current study.…”

“…MitraClip is intended to reduce MR via focal leaflet coaptation. However, prior echo studies by our group and others have shown increased left ventricular (LV) size to augment risk for recurrent MR after MitraClip implantation [5], supporting the notion that remodeling indices beyond mitral valve anatomy impact therapeutic response. It is also possible that the device itself contributes to risk for MR recurrence.…”

“…Recurrent MR after MitraClip is a substantial problem. Studies have reported residual or recurrent (> mild) MR in over one third of patients undergoing MitraClip [2–5]. Even when implanted in controlled research settings, MitraClip response varies – as evidenced by two recent trials (MITRA-FR, COAPT) that yielded conflicting results regarding impact of MitraClip on MR reduction and clinical outcomes [6, 7].…”

Percutaneous Mitral Valve Repair: Multi-Modality Cardiac Imaging for Patient Selection and Intra-Procedural Guidance

“…Lubos et al found that effective regurgitant orifice area >70.8 mm 2 and mitral valve area ≤ 3.0 cm 2 independently predicted clip failure (defined by aborted procedure or inability to reduce MR to ≤ 2+ in severity) (33). A recent paper studying treatment of degenerative MR suggested that higher baseline left-ventricular end-diastolic diameter and mitral annular diameter predict greater than mild residual MR after mitraclip (17). In current clinical practice, absolute anatomic limitations are very few (18).…”