Improved mitral valve coaptation and reduced mitral valve annular size after percutaneous mitral valve repair (PMVR) using the MitraClip system

Implications of Mitral Annular Disjunction in Patients Undergoing Transcatheter Edge-to-Edge Repair for Degenerative Mitral Regurgitation

BACKGROUND

Little is known about mitral transcatheter edge-to-edge repair (TEER) in patients with mitral annular disjunction (MAD).

OBJECTIVES

The authors sought to explore TEER for degenerative mitral regurgitation (MR) according to MAD status.

METHODS

We retrospectively analyzed 271 consecutive patients (median age 82 [Q1-Q3: 75-88] years, 60.9% men) undergoing an isolated, first-ever TEER for whom there were viewable preprocedural echocardiograms. Stratified by MAD status at baseline, the cohort was evaluated for all-cause mortality, heart failure hospitalizations, and mitral reinterventions-the composite of which constituted the primary outcome-as well as functional capacity and residual MR, all along the first postprocedural year.

RESULTS

Individuals with (n = 62, 22.9%) vs without MAD had more extensive prolapse and larger valve dimensions. Although the former's procedures were longer, utilizing more devices per case, technical success rate and residual MR were comparable. MAD presence was associated with higher mortality risk (HR: 2.64; 95% CI: 1.82-5.52; P = 0.014), and increased MAD length-with lower odds of functional class ≤II (OR: 0.65; 95% CI: 0.47-0.88; P = 0.006). Among 47 MAD patients with retrievable 1-month data, MAD regressed in 91.5% and by an overall 50% (Q1-Q3: 22%-100%) compared with baseline (P < 0.001). A greater MAD shortening conferred attenuated risk for the primary outcome.

CONCLUSIONS

In our experience, TEER for degenerative MR accompanied by MAD was feasible and safe; however, its postprocedural course was somewhat less favorable. MAD shortening following TEER was observed in most patients and proved prognostically beneficial.

Annuloplasty effect of transcatheter edge-to-edge repair with MitraClip system on multiple degenerative mitral regurgitations

BACKGROUND

Previous reports have shown a mitral annuloplasty-like effect after MitraClip, i.e. a shortening of the anterior-posterior diameter of mitral valve annulus. However, the clinical benefit of this phenomenon is unclear.

CASE SUMMARY

An 87-year-old woman with multiple degenerative mitral regurgitation (MR) jets, including a central-medial jet and a lateral jet, underwent MitraClip procedure. After a single clip implantation, anterior-posterior diameter of mitral annulus was shortened and both MR jets were significantly reduced.

DISCUSSION

Even in the case of multiple MR jets, a single clip deployment with the MitraClip system may provide an acceptable MR reduction if the clip shows the mitral annuloplasty effect.

Transcatheter edge-to-edge-repair of functional mitral regurgitation induces significant remodeling of mitral annular geometry

Background

Mitral annular alterations in the context of heart failure often lead to severe functional mitral regurgitation (FMR), which should be treated with transcatheter edge-to-edge repair (M-TEER) according to current guidelines. M-TEER's effects on mitral valve (MV) annular remodeling have not been well elucidated.

Methods

141 consecutive patients undergoing M-TEER for treatment of FMR were included in this investigation. Comprehensive intraprocedural transesophageal echocardiography was used to assess the acute effects of M-TEER on annular geometry.

Results

Average patient age was 76.2 ± 9.6 years and 46.1% were female patients. LV ejection fraction was reduced (37.0% ± 13.7%) and all patients had mitral regurgitation (MR) grade ≥III. M-TEER achieved optimal MR reduction (MR ≤ I) in 78.6% of patients. Mitral annular anterior-posterior diameters (A-Pd) were reduced by -6.2% ± 9.5% on average, whereas anterolateral-posteromedial diameters increased (3.7% ± 8.9%). Overall, a reduction in MV annular areas was observed (2D: -1.8% ± 13.1%; 3D: -2.7% ± 13.7%), which strongly correlated with A-Pd reduction (2D: r = 0.6, p < 0.01; 3D: r = 0.65, p < 0.01). Patients that achieved A-Pd reduction above the median (≥6.3%) showed significantly lower rates of the composite endpoint rehospitalization for heart failure or all-cause mortality than those with less A-Pd reduction (9.9% vs. 28.6%, p = 0.037, log-rank p = 0.039). Furthermore, patients reaching the composite endpoint had an increase in annular area (2D: 3.0% ± 15.4%; 3D: 1.9% ± 15.3%), whereas those not reaching the endpoint showed a decrease (2D: -2.7% ± 12.4%; 3D: -3.6% ± 13.3%), although residual MR after M-TEER was similar between these groups (p = 0.57). In multivariate Cox regression adjusted for baseline MR, A-Pd reduction ≥6.3% remained a significant predictor of the combined endpoint (OR: 0.35, 95% CI: 0.14-0.85, p = 0.02).

Conclusion

Our findings indicate that effects of M-TEER in FMR are not limited to MR reduction, but also have significant impact on annular geometry. Moreover, A-Pd reduction, which mediates annular remodeling, has a significant impact on clinical outcome independent of residual MR.

Improved mid-term stability of MR reduction with an increased number of clips after percutaneous mitral valve repair in functional MR

Background

Percutaneous mitral valve repair (PMVR) has evolved to be a standard procedure in suitable patients with mitral regurgitation (MR) not accessible for open surgery. Here, we analyzed the influence of the number and positioning of the clips implanted during the procedure on MR reduction analyzing also sub-collectives of functional and degenerative MR (DMR).

Results

We included 410 patients with severe MR undergoing PMVR using the MitraClip® System. MR and reduction of MR were analyzed by TEE at the beginning and at the end of the PMVR procedure. To specify the clip localization, we sub-divided segment 2 into 3 sub-segments using the segmental classification of the mitral valve.

Results

We found an enhanced reduction of MR predominantly in DMR patients who received more than one clip. Implantation of only one clip led to a higher MR reduction in patients with functional MR (FMR) in comparison to patients with DMR. No significant differences concerning pressure gradients could be observed in degenerative MR patients regardless of the number of clips implanted. A deterioration of half a grade of the achieved MR reduction was observed 6 months post-PMVR independent of the number of implanted clips with a better stability in FMR patients, who got 3 clips compared to patients with only one clip.

Conclusions

In patients with FMR, after 6 months the reduction of MR was more stable with an increased number of implanted clips, which suggests that this specific patient collective may benefit from a higher number of clips.

The impact of transcatheter edge-to-edge repair on mitral valve annular geometry

PURPOSE OF REVIEW

Mitral valve transcatheter edge-to-edge repair (TEER) is becoming increasingly common to treat severe mitral regurgitation. However, the lack of concomitant annuloplasty raises concerns regarding its durability. As a result, there is an emerging body of literature evaluating the impacts of TEER on mitral annular geometry. In this review, we summarize the most recent literature evaluating the impacts of TEER on annular geometry in the acute, intermediate and long-term. We also review the relationship between changes in annular geometry and clinical endpoints.

RECENT FINDINGS

Current evidence suggests that TEER acutely induces favourable changes in mitral annular size and shape, which may persist for at least up to 1 year. Few studies suggest that TEER-induced annular remodelling is associated with positive clinical outcomes.

SUMMARY

The current body of literature is sparse and limited to primarily small case series. Data from the surgical literature suggest that ringless edge-to-edge repair is associated with eventual failure. Unfortunately, few studies evaluate TEER-induced annular changes beyond the acute postprocedural phase. Future research needs to focus on and evaluate the significance of TEER-induced changes in annular dimensions in the long-term.

Acute changes in mitral valve geometry after percutaneous valve repair with MitraClip XTR by three-dimensional echocardiography

BACKGROUND

Mitral valve (MV) repair with MitraClip system is a safe treatment option for high-risk patients with significant mitral regurgitation (MR). We aimed to characterize, by three-dimensional echocardiography (3D-E), changes occurring in MV after implantation of third generation MitraClip XT_R device, with specific reference to the underlying MR mechanism (functional vs degenerative, FMR vs DMR).

METHODS

We prospectively enrolled 59 patients, who underwent intra-procedural 3D-E before and after device deployment. Three-D datasets were analyzed off-line, using a dedicated semiautomatic software, to obtain parametric quantification of mitral anatomy.

RESULTS

Post-procedural MR of mild or lesser degree was achieved in 40 patients (68%), with no differences between FMR and DMR (p 0.9). After MitraClip XT_R implantation, the FMR group experienced an immediate annular resizing, with reduction of antero-posterior diameter (p 0.024) and sphericity index (p 0.017), next to a recovery of physiological saddle-shape, defined by lower non-planar angle (p ≤0.001) and higher annulus height to commissural width ratio (p ≤0.001). On the opposite, the DMR group revealed a significant decrease of maximum annular velocity (p 0.027), addressing a mechanic effect of the device deployment. Finally, baseline anterior mitral leaflet angle was found as an independent predictor of acute procedural result (OR 6.7, [CI 1.01-44.33], p 0.049).

CONCLUSIONS

MitraClip XT_R implantation acts in restoring the original mitral geometry, with distinctive effects according to MR mechanism. Three-D parametric quantification of MV sheds new light on changes occurring in the valvular apparatus, and helps identifying possible new predictors of acute procedural success.

Impact of Leaflet Tethering on Residual Regurgitation in Patients With Degenerative Mitral Disease After Interventional Edge-to-Edge Repair

Background: Grade 2+ residual mitral regurgitation (MR 2+) is associated with the recurrence of MR and a lower survival rate in interventional mitral valve (MV) edge-to-edge (EE) repair. We sought to determine the MV anatomic factors affecting residual MR 2+ during interventional EE repair with the ValveClamp system in patients with degenerative MR (DMR).

Methods: In this multicenter study, 62 patients with significant (grade 3+ to 4+) DMR underwent ValveClamp implantation across eight centers from July 2018 to December 2019. Patient clinical, anatomical, and procedural characteristics were prospectively collected and retrospectively analyzed.

Results: A single clamp was implanted in 59 patients, and two clamps were implanted in three patients. Residual MR 2+ was found in 14 patients (22.6%) immediately after the ValveClamp procedure. Patients with residual MR 2+ showed significantly larger preoperative tenting sizes and annular dimensions than the residual MR ≤1+ group. Multivariate analysis identified tenting volume as the major determinant of residual MR 2+ after ValveClamp procedures (odds ratio, 1.410 per 0.1-mL/m² increase; 95% confidence interval, 1.167–1.705; P < 0.001). Receiver operating characteristic curves identified a tenting volume index ≥0.82 mL/m² as the optimal cutoff point to predict residual MR 2+ (area under curve, 0.84). Patients with a tenting volume index ≥0.82 mL/m² were more likely to develop recurrent 3+ MR or undergo MV surgery during short-term follow-up (P < 0.001).

Conclusions: Preoperative assessment of the tenting volume index will help to predict intraoperative residual MR 2+ in patients with DMR receiving EE-based interventional repair. Improvements in the interventional strategy are warranted for sustained MR reduction in patients with DMR with unfavorable anatomy.

Changes in mitral valve geometry after percutaneous valve repair with the MitraClip® System

The aim of our study was to assess the anatomical changes of the mitral valve apparatus after percutaneous repair with the MitraClip® system. We included consecutive patients who underwent MitraClip® implantation in our center. Patients were assessed by 2- and 3-dimensional transesophageal echocardiography, acquired before and immediately after MitraClip® implantation. Off-line images analysis was performed to assess mitral annular diameters (antero-posterior and inter-commisural), area and circumference. Mitral tenting distance, area and volume were evaluated for functional mitral regurgitation. Patients had a 2-dimensional transthoracic echocardiography at follow-up (8 months). 38 patients with successful results (residual mitral regurgitation grade ≤ II) were included. The anteroposterior annulus diameter (ADP) decreased (from 35 ± 5 to 28 ± 5 mm, p < 0.001) with smaller decreases in the annular area and circumference and in the inter-commissural diameter. Annular ellipticity improved. The reduction in APD and tenting distance was sustained at follow-up. Successful percutaneous mitral valve repair with the MitraClip® system induces a stable change in mitral valve geometry mainly at the ADP, suggesting a significant annuloplasty that contributes to the reduction of mitral regurgitation.

Effect of a novel transcatheter edge-to-edge repair device on the three-dimensional geometry of mitral valve in degenerative mitral regurgitation

OBJECTIVES

We sought to assess the acute intraprocedural effects of the ValveClamp system in DMR patients on the mitral valve (MV) three-dimensional (3D) geometry and the association of these effects with mitral regurgitation (MR) reduction.

BACKGROUND

Few data are available about the specific impact of transcatheter edge-to-edge repair in patients with degenerative mitral regurgitation (DMR).

METHODS

Thirty-five symptomatic patients (age 74.26 ± 6.61 years) with Grade 3 to 4+ degenerative MR underwent 3D transoesophageal echocardiography (TEE) during ValveClamp implantation. Volumetric data sets were retrospectively analyzed using mitral valve quantitative 3D modeling software.

RESULTS

Mitral valve annular anterior-posterior (AP) diameter decreased from 33.24 ± 4.03 to 31.12 ± 3.66 mm (p < .001), and prolapse height from 4.78 ± 2.19 to 2.32 ± 1.92 mm (p < .001), and total exposed leaflet area from 1,110.29 ± 224.21 mm² to 1,013.44 ± 228.71 mm (p = .004). Accordingly, we observed a significant reduction of MR severity after ValveClamp implantation. Multivariable analysis revealed postprocedural MR reduction was associated with shortening in anterior-posterior diameter (coefficient 0.427, p = .008) and reduction in prolapse height (coefficient 0.369, p = .021).

CONCLUSIONS

ValveClamp implantation exerts an acute effect on the 3D MV geometry. Postprocedural reduction in AP diameter and reduction in prolapse height correlates with MR downgrading in patients with degenerative MR.

A Comprehensive Engineering Analysis of Left Heart Dynamics After MitraClip in a Functional Mitral Regurgitation Patient

Percutaneous edge-to-edge mitral valve (MV) repair using MitraClip has been recently established as a treatment option for patients with heart failure and functional mitral regurgitation (MR), which significantly expands the number of patients that can be treated with this device. This study aimed to quantify the morphologic, hemodynamic and structural changes, and evaluate the biomechanical interaction between the MitraClip and the left heart (LH) complex of a heart failure patient with functional MR using a fluid-structure interaction (FSI) modeling framework. MitraClip implantation using lateral, central and double clip positions, as well as combined annuloplasty procedures were simulated in a patient-specific LH model that integrates detailed anatomic structures, incorporates age- and gender-matched non-linear elastic material properties, and accounts for mitral chordae tethering. Our results showed that antero-posterior distance, mitral annulus spherecity index, anatomic regurgitant orifice area, and anatomic opening orifice area decreased by up to 28, 39, 52, and 71%, respectively, when compared to the pre-clip model. MitraClip implantation immediately decreased the MR severity and improved the hemodynamic profile, but imposed a non-physiologic configuration and loading on the mitral apparatus, with anterior and posterior leaflet stress significantly increasing up to 210 and 145% during diastole, respectively. For this patient case, while implanting a combined central clip and ring resulted in the highest reduction in the regurgitant volume (46%), this configuration also led to mitral stenosis. Patient-specific computer simulations as used here can be a powerful tool to examine the complex device-host biomechanical interaction, and may be useful to guide device positioning for potential favorable clinical outcomes.

Mid-term repair durability after MitraClip implantation in patients with functional mitral regurgitation

BACKGROUND

The aim of this study was to identify variables that are associated with the durability of percutaneous repair of secondary mitral regurgitation at 6-month follow-up.

METHODS AND RESULTS

Thirty-five consecutive patients with functional mitral regurgitation scheduled for MitraClip implant were enrolled. Left ventricular (LV) volumes and function and mitral valve characteristics were assessed before and immediately after MitraClip implantation using three-dimensional transesophageal echocardiography. Five patients with an unsuccessful procedure were excluded. The other patients were subdivided according to repair durability: group 1 with a durable repair (19 patients, 65%) and group 2 with significant mitral regurgitation recurrence (11 patients, 35%). At baseline, group 1 patients had smaller and more elliptical mitral valve annulus (1055 ± 241 vs. 1273 ± 359 mm, P = 0.02 and 125 ± 11 vs. 117 ± 16%, P = 0.02), a smaller left atrial volume (54.1 ± 26 vs. 71.5 ± 20 ml, P = 0.005) and lower systolic pulmonary artery pressure (38 ± 11 vs. 49 ± 12 mmHg, P = 0.03). Baseline LV end systolic volume had a linear correlation with the 3D annulus area (P = 0.048) and an inverse correlation with annulus ellipticity (P = 0.021). Group 1 patients showed an increase in annulus ellipticity after MitraClip (125 ± 17 vs. 141 ± 23%, P = 0.014).

CONCLUSION

Percutaneous mitral valve repair leads to a significant and stable mitral regurgitation reduction in a large number of patients. Annulus dimensions and remodeling as well as left atrial area and pulmonary hypertension seem to be associated with durability of the procedure.

The year 2018 in the European Heart Journal-Cardiovascular Imaging: Part II

European Heart Journal - Cardiovascular Imaging was launched in 2012 as a multimodality cardiovascular imaging journal. It has gained an impressive impact factor during its first 5 years and is now established as one of the top cardiovascular journals and has become the most important cardiovascular imaging journal in Europe. The most important studies from 2018 will be highlighted in two reports. Part I of the review has focused on studies about myocardial function and risk prediction, myocardial ischaemia, and emerging techniques in cardiovascular imaging, while Part II will focus on cardiomyopathies, congenital heart diseases, valvular heart diseases, and heart failure.

ECG changes after percutaneous edge-to-edge mitral valve repair

Background

Mitral regurgitation (MR) has a severe impact on hemodynamics and induces severe structural changes in the left atrium. Atrial remodeling is known to alter excitability and conduction in the atrium facilitating atrial fibrillation and atrial flutter. PMVR is a feasible and highly effective procedure to reduce MR in high‐risk patients, which are likely to suffer from atrial rhythm disturbances. So far, electroanatomical changes after PMVR have not been studied.

Hypothesis

In the current study, we investigated changes in surface electrocardiograms (ECGs) of patients undergoing PMVR for reduction of MR.

Methods

We evaluated 104 surface ECGs from patients in sinus rhythm undergoing PMVR. P wave duration, P wave amplitude, PR interval, QRS duration, QRS axis, and QT interval were evaluated before and after PMVR and at follow‐up.

Results

We found no changes in QRS duration, QRS axis, and QT interval after successful PMVR. However, P wave duration, amplitude, and PR interval were significantly decreased after reduction of MR through PMVR (P < .05, respectively).

Conclusion

The data we provide offers insight into changes in atrial conduction after reduction of MR using PMVR in patients with sinus rhythm.

Previous TAVR in patients undergoing percutaneous edge-to-edge mitral valve repair (PMVR) affects improvement of MR

Background

Patients after transcatheter aortic valve replacement (TAVR) and persistent severe mitral regurgitation (MR) are increasingly treated with percutaneous edge-to-edge mitral valve repair (PMVR). The impact of a former TAVR on PMVR procedures is not clear.

Methods and results

We retrospectively analyzed 332 patients undergoing PMVR using the MitraClip system with respect to procedural and clinical outcome. 21 of these 332 patients underwent TAVR before PMVR. Intra-procedural transthoracic (TTE) and transesophageal echocardiograms (TEE) immediately before and after clip implantation as well as invasive hemodynamic measurements were evaluated. At baseline, we found a significantly smaller mitral valve anterior-posterior diameter in the TAVR cohort (p < 0.001). A reduction of MR by at least three grades was achieved in a smaller fraction in the TAVR cohort as compared to the cohort with a native aortic valve (p = 0.02). Accordingly, we observed a smaller post-procedural cardiac output in the TAVR cohort (p = 0.02).

Conclusion

PMVR in patients who had a TAVR before, is associated with altered MR anatomy before and a reduced improvement of MR after the procedure. Future larger and prospective studies will have to determine, whether a previous TAVR influences long-term clinical outcome of patients undergoing PMVR.