Advanced Steering Maneuvers for Special Situations in Mitral Valve Transcatheter Edge-to-edge Repair

The use of transcatheter percutaneous edge-to-edge mitral valve repair with the MitraClip (Abbott) for the treatment of mitral regurgitation has rapidly expanded since it received Food and Drug Administration approval. Currently, patients with more complex mitral valve anatomies are undergoing this procedure with progressively improving clinical outcomes. This review focuses on the advanced steering maneuvers needed for the technical success of the MitraClip procedure and discusses several scenarios where such advanced steering maneuvers may be needed. These include an anterior transseptal puncture, low or high transseptal puncture with unfavorable transseptal height to mitral valve, large gap height, patients with mitral regurgitation due to dehiscence of a prior mitral valve annuloplasty ring, placing multiple/adjacent MitraClips, or redo edge-to-edge mitral valve repair. Knowledge and mastery of such advanced steering maneuvering techniques can allow operators to complete the procedure successfully with low rate of complications even in difficult scenarios.

A Simulation Study of the Effects of Number and Location of MitraClips on Mitral Regurgitation

Background

MitraClip (MC) is a device that is implanted on the mitral valve (MV) percutaneously to treat severe mitral regurgitation (MR). It is common practice to place the MCs at the site of the most significant MR jets identified by echocardiography.

Objectives

We used computational modeling to examine changes in MR after MC placement.

Methods

Echocardiographic images from 29 patients with MR were analyzed to reconstruct geometries for finite element simulations and created fluid structure interaction models of the MV with deformable hyperelastic material, the left ventricle as the surrounding geometry, and blood flow. Blood flow was modelled with smoothed particle hydrodynamics. The number of blood particles on the atrial side of MV was used to estimate MR. MC placement was based on the MR jets (jet-based strategy using primary and secondary jets) and simulation models using various MCs locations.

Results

Computational modelling was able to quantitate reductions in MR after MC placement. Reduction in MR was related to the number of MCs used: 42% reduction with 1 MC, 62% with 2 MCs, and 88% with 3 MCs. Using 2 MCs did not always result in an MR reduction greater than with a single MC. In 31% (9 of 29) of patients, the jet-based strategy did not lead to maximum MR reduction. The majority of patients (89%) who did not have maximal MR reduction with the MC placement using the jet-based strategy, had wide jets, and/or had multiple jets.

Conclusions

Subject-specific simulation models may be helpful to identify optimal locations for MC placement in patients with MR.

Pre-procedural predictors for multiple clips in percutaneous edge-to-edge mitral valve repair

Background

Percutaneous mitral valve (MV) clipping for mitral regurgitation (MR) revolutionized MV repair; however, valve anatomies and pathologies vary. Often multiple clips are required, and predicting this pre-procedurally would be useful. We evaluated pre-procedural predictors for multiple clips.

Results

We retrospectively analyzed 127 severe MR patients treated by mitral clipping between January 2011 and August 2018. Patients were grouped according to the use of a single (group I) or multiple clips (group II) and pre-procedure echocardiographs compared. No demographic differences existed except group II had more males (68.1%) than group I (48.3%). Mean left atrial diameter was larger in group II, 51 ± 9 mm, than group I, 48 ± 5 mm, p = 0.026. Mean mitral annular diameter differed: 34 ± 4mm (group II) versus 33 ± 3 mm (group I), p = 0.017. The vena contracta was broader in group II than group I (6.6 ± 1 mm vs. 6 ± 0.9 mm, p = 0.001). Severe mitral annular calcification occurred more in group I (36.2%) than group II (10.1%), p = 0.0001. On multivariate analysis, vena contracta width correlated positively with multiple clips (B 0.125, p = 0.013), but severe annular calcification correlated inversely (B − 0.35, p = 0.002).

Conclusions

Vena contracta width and severe annular calcification are factors to consider when planning MV clipping.

Implantation of one, two or multiple MitraClips for transcatheter mitral valve repair: insights from a 1824-patient multicenter study

BACKGROUND

Transcatheter mitral valve repair (TMVR) with the MitraClip device is an established treatment for mitral regurgitation (MR). More than one MitraClip may be implanted if a single one does not reduce MR adequately. We aimed at appraising the outlook of patients undergoing implantation of one, two or multiple MitraClips for TMVR.

METHODS

Exploiting the ongoing prospective GIse registry Of Transcatheter treatment of mitral valve regurgitaTiOn (GIOTTO) Study dataset, we compared patients, procedural details and outcomes distinguishing those receiving one, two or multiple MitraClips. The primary endpoint was the composite of 1-year cardiac death or rehospitalization for heart failure. Additional endpoints included all cause death, surgical mitral repair, and functional class. Multivariable adjusted Cox proportional hazard analysis was used for confirmatory purposes.

RESULTS

As many as 1824 patients were included: 718 (39.4%) treated with a single MitraClip, and 940 (51.5%) receiving two MitraClips, and 166 (9.1%) receiving three or more. Significant differences were found for baseline features, including age, female gender, diabetes mellitus, hypertension, chronic obstructive pulmonary disease, prior myocardial infarction, atrial fibrillation, permanent pacemaker, cardiac resynchronization therapy, implantable cardioverter defibrillator, and prior mitral valve repair (all p<0.05). Several imaging features were also different, including left ventricular dimensions, MR severity and proportionality, mitral valve area, flail leaflet, and pulmonary vein flow (all p<0.05). Among procedural features, significant differences were found for anesthesia type, MitraClip type, fluoroscopy, device, and operating room times, postprocedural mitral gradient, residual MR, smoke-like effect, device success partial detachment and surgical conversion (all p<0.05). In-hospital death occurred more frequently in patients receiving multiple MitraClips, and the same applied severe residual MR (all p<0.05). Mid-term follow-up (15±13 months) showed significant difference in the risk of death, cardiac death, rehospitalization for heart failure, and their composites, mainly, but not solely, associated with multiple MitraClips (all p<0.05). Adjusted analysis confirmed the significantly increased risk of composite adverse events when comparing the multiple vs single MitraClip groups (p=0.014 for death and rehospitalization, p=0.013 for cardiac death or rehospitalization).

CONCLUSIONS

Implantation of one or two MitraClips is associated with favorable clinical outcomes. Conversely, bail-out implantation of three or more MitraClips may portend a worse long-term prognosis.

Multiple MitraClips: The balancing act between pressure gradient and regurgitation

OBJECTIVE

Transcatheter mitral valve repair with the MitraClip is used for the symptomatic management of mitral regurgitation (MR). The challenge is reducing MR while avoiding an elevated mitral valve gradient (MVG). This study assesses how multiple MitraClips used to treat MR can affect valve performance.

METHODS

Six porcine mitral valves were assessed using an in vitro left heart simulator in the native, moderate-to-severe MR, and severe MR cases. MR cases were tested in the no-MitraClip, 1-MitraClip, and 2-MitraClip configurations. Mitral regurgitant fraction (MRF), MVG, and effective orifice area (EOA) were quantified.

RESULTS

Native MRF, MVG, and EOA were 14.22%, 2.59 mm Hg, and 1.64 cm², respectively. For moderate-to-severe MR, MRF, MVG, and EOA were 34.07%, 3.31 mm Hg, and 2.22 cm², respectively. Compared with the no-MitraClip case, 1 MitraClip decreased MRF to 18.57% (P < .0001) and EOA to 1.50 cm² (P = .0002). MVG remained statistically unchanged (3.44 mm Hg). Two MitraClips decreased MRF to 14.26% (P < .0001) and EOA to 1.36 cm² (P = .0001). MVG remained unchanged (3.29 mm Hg). For severe MR, MRF, MVG, and EOA were 59.79%, 4.98 mm Hg, and 2.73 cm², respectively. Compared with the no-MitraClip case, 1 MitraClip decreased MRF to 30.72% (P < .0001) and EOA to 1.82 cm² (P < .0001); MVG remained unchanged (4.03 mm Hg). MVG remained statistically unchanged. Two MitraClips decreased MRF to 23.10% (P < .0001) and EOA to 1.58 cm² (P < .0001); MVG remained statistically unchanged (3.82 mm Hg). Both MR models yielded no statistical difference between 1 and 2 MitraClips.

CONCLUSIONS

There is limited concern regarding elevation of MVG when reducing MR using 1 or 2 MitraClips, although 2 MitraClips did not significantly continue to reduce MRF.

MitraClip device for patients with functional mitral valve regurgitation: A systematic review

BACKGROUND

MitraClip device is a novel therapeutic option for patients with degenerative mitral valve regurgitation. Nevertheless, several studies have also focused on the safety and efficacy of this method in functional mitral valve regurgitation (FMR).

AIM

To systematically review all original studies that provided mortality data among FMR patients treated with MitraClip.

MATERIALS AND METHODS

We conducted an in-depth literature search of 3 electronic databases (Medline, Scopus and Cochrane Library) in order to identify studies investigating the efficacy of MitraClip in FMR. Thirty-day and 12-month mortality after MitraClip implantation were the measured outcomes.

RESULTS

Twenty-eight studies, involving 2383 patients, were included. The phenotype of the studied population was characterized by clinical and echocardiographic parameters suggesting severe FMR (NYHA III-IV: 91%, MR≥3+: 98%) with high surgical risk (mean Euroscore: 24.6%). The Mitraclip device was successfully implanted in 95.8% of patients, resulting in a reduction of two or more degrees of MR. Thirty day and 12-month mortality rates were estimated to be 2.3% and 18.9%, respectively.

CONCLUSIONS

MitraClip appears to be a safe therapeutic option for patients with FMR who are considered to be at high surgical risk.

Short-term and 1-year outcomes after MitraClip therapy in functional versus degenerative mitral regurgitation patients: a systematic review and meta-analysis

Background

Differences in short-term and 1-year outcomes of percutaneous edge-to-edge mitral repair between patients with functional and degenerative mitral regurgitation (MR) remain unclear. We performed a systematic review and meta-analysis to investigate the safety and efficacy of MitraClip (MC) in patients with different MR etiologies.

Methods

This study systematically searched three common databases for studies on MC therapy until November 2017. The studies meeting the standard inclusion criteria were included. The data at baseline, short-term and 1-year clinical and echocardiographic outcomes were obtained and analyzed. All data were checked by another reviewer.

Results

Thirteen studies totalling 2,351 patients investigating the short-term and 1-year outcomes of MC in patients with functional MR (FMR) versus degenerative MR (DMR) were included for further analysis. FMR patients presented a higher risk profile at baseline. There was no difference in short-term outcomes between DMR and FMR for post-procedural MR grade 0-2 (76.8% vs. 77.1%; P=0.428), mean trans-mitral gradient (3.92 vs. 3.50 mmHg; P=0.098), 30-day mortality rate (0.05% vs. 0.03%; P=0.118) and 30-day NYHA I-II (85.3% vs. 78.7%; P=0.211). FMR patients had a higher rate of acute procedural success compared to the DMR patient group (91.2% vs. 95.2%; P=0.016). A greater portion of DMR patients implanted two or more MCs than the FMR patients (41.4% vs. 35.7%; P=0.043). For the 1-year outcomes, no difference was found in the mortality rate (13.0% vs. 15.2%; P=0.268) and proportion of patients with post-procedural MR grades 0-2 (75.0% vs. 80.7%; P=0.106).

Conclusions

Despite a higher risk profile in FMR patients, the short-term and 1-year outcomes were not significantly different. We conclude that MC therapy is similar between FMR and DMR patients until 1-year follow-up. Large randomized trials are warranted to fully and further assess the clinical impact of the procedure in these two MR etiologies over a longer period of time.

Percutaneous mitral valve repair with the MitraClip NT™ system in a patient presenting with prolonged cardiogenic shock

The MitraClip NT™ system for the treatment of severe mitral valve regurgitation is effective and safe – even for patients suffering from cardiogenic shock. The use of an intra‐aortic balloon pump expands the range of possible applications to this particular group of challenging patients.

Current MitraClip experience, safety and feasibility in the Netherlands

Purpose

Data on MitraClip procedural safety and efficacy in the Netherlands are scarce. We aim to provide an overview of the Dutch MitraClip experience.

Methods

We pooled anonymised demographic and procedural data of 1151 consecutive MitraClip patients, from 13 Dutch hospitals. Data was collected by product specialists in collaboration with local operators. Effect on mitral regurgitation was intra-procedurally assessed by transoesophageal echocardiography. Technical success and device success were defined according to modified definitions of the Mitral Valve Academic Research Consortium (MVARC).

Results

Median age was 76 (interquartile range 69–82) years and 59% were males. Patients presented with ≥moderate mitral regurgitation and a predominance of functional mitral regurgitation (72%). Overall, 611 (53%) patients were treated with one Clip, 486 (42%) with ≥2 Clips and 54 (5%) received no Clip. The number of patients with ≥2 Clips increased from 22% in 2009 to 52% in 2016. Device success and technical success were 91 and 95%, respectively, and were consistent over the years. Significant reduction of mitral regurgitation by MitraClip was achieved in 94% of patients and was observed more often in patients with functional mitral regurgitation (95% vs. 91%, p = 0.025). Device time declined from 145 min in 2009 to 55 min in 2016.

Conclusion

MitraClip experience in the Netherlands is growing with excellent technical success and device success. Over the years, device time decreased and more patients were treated with ≥2 Clips.

Long-Term Outcomes After MitraClip Implantation According to the Presence or Absence of EVEREST Inclusion Criteria

Numerous patients are treated with the MitraClip, although they do not fulfill the stringent inclusion criteria of the Endovascular Valve Edge-to-Edge Repair Study (EVEREST) trials. The outcome of those patients is not well known. Therefore, we compared the long-term outcome after MitraClip treatment between patients who matched (group 1) and did not match (group 2) the EVEREST criteria. One hundred thirty-four consecutive patients were treated from September 2009 to July 2012: 59 patients (44%) in group 1 versus 75 patients (56%) in group 2. Investigated end points were acute procedural success (for group 1 vs 2: 97% vs 95%; p = 0.694), all-cause mortality (28% vs 27%; p = 0.656), reintervention (RI) rate (11% vs 37%; p = 0.010), and improvement in mitral regurgitation (MR) (-1.3 ± 1 vs -1.5 ± 1, p = 0.221) and in New York Heart Association functional class (-0.7 ± 1 vs -0.9 ± 0.8, p = 0.253) during the follow-up of 33 months (27.9 to 38.3). The morphologic extent of a flail leaflet was an independent predictor for RI. In conclusion, although the overall outcome was comparable between both groups, recurrent symptomatic MR with need for RI was higher in group 2, mainly because of complex valve pathologies: especially flail width >15 mm and gap ≥10 mm. Improvements in the interventional strategy are warranted for reducing the need for RI in patients with primary MR.

Immediate and 12-Month Outcomes of Ischemic Versus Nonischemic Functional Mitral Regurgitation in Patients Treated With MitraClip (from the 2011 to 2012 Pilot Sentinel Registry of Percutaneous Edge-To-Edge Mitral Valve Repair of the European Society of Cardiology)

In literature, there are limited data comparing ischemic mitral regurgitation (I-MR) versus nonischemic MR regarding outcomes after percutaneous "edge-to-edge" repair. We aimed to describe the early and 12-month results after MitraClip device implantation regarding the 2 etiologies. From January 2011 to December 2012, the Transcatheter Valve Treatment Sentinel Pilot Registry included 452 patients with MR who underwent MitraClip procedure in 25 centers across Europe. The prevalent etiology was I-MR (235 patients, 52.0%). I-MR group had a significantly higher proportion of men (74.9 vs 59.9%, p <0.001) and surgical risk (logistic EuroSCORE 24.8 ± 18.2 vs 18.8 ± 16.3, p <0.001). Acute procedural success was high (96%) and similar between groups (p = 0.48). Patients with I-MR required a higher, albeit not significant, number of clips to reduce MR (p = 0.08). Inhospital mortality was low (2.0%) without significant differences between etiologies. The estimated 1-year mortality and rehospitalization rates were 15.0% and 25.8%, respectively, without significant differences between groups. Paired echocardiographic data showed a persistent improvement of MR at 1 year in both etiologies. Despite a significant overall reverse atrial remodeling after clip, there were no significant changes in left ventricular volumes. In conclusion, this large independent cohort showed that percutaneous "edge-to-edge" therapy was associated with early- and long-term improvement of MR severity and functional condition both in patients with I-MR and nonischemic MR. There were no significant differences between the 2 etiologies regarding survival and freedom from rehospitalization due to heart failure at the 1-year follow-up.

Managing mitral regurgitation: focus on the MitraClip device

Based on the principle of surgical edge-to-edge mitral valve repair (MVR), the MitraClip percutaneous MVR technique has emerged as a minimally invasive option for MVR. This catheter-based system has been widely demonstrated to be safe, although inferior to surgical MVR. Studies examining patients with ≥3+ mitral regurgitation (MR) show that, for all patients treated, freedom from death, surgery, or MR ≥3+ is in the 75%–80% range 1 year following MitraClip implantation. Despite its inferiority to surgical therapy, in high-risk surgical patients, data suggest that the MitraClip system can be employed safely and that it can result in symptomatic improvement in the majority of patients, while not precluding future surgical options. MitraClip therapy also appears to reduce heart failure readmissions in the high-risk cohort, which may lead to an economic benefit. Ongoing study is needed to clarify the impact of percutaneous mitral valve clipping on long-term survival in high-risk populations, as well as its role in other patient populations, such as those with functional MR.

Transseptal and transmitral Parachute® implantation in conjunction with "MitraClipping"

AIMS

Parachute® implantation (PI) is an attractive treatment option for patients with left ventricular apical aneurysms (LVAA). So far, only the retrograde approach has been approved for PI. Unfortunately, severe functional mitral regurgitation (MR) restricts PI. Thus, we were intrigued to combine PI and MitraClip therapy (MCT) as a new transvenous hybrid concept.

METHODS AND RESULTS

PI was performed via a transseptally placed MitraClip guide in six consecutive patients (age 73.8±5.2; 66% male). Immediately after PI, MR was treated by MCT. Invasive right and left heart haemodynamics were taken before and after PI and MCT, respectively. Procedural success was 100%. PI induced a numerical increase in cardiac output (CO: +36.4; p=0.15) and stroke volume (SV: +30.1%; p=0.09), despite some evidence of MR aggravation. Subsequent MCT successfully reduced MR at least to mild in five patients and to moderate in one patient. SV and CO demonstrated a further increase (SV: +44.3%, p=0.03; CO: +44.5%; p=0.03).

CONCLUSIONS

The study documents for the first time the feasibility of transseptal and transmitral PI. Nevertheless, pre-procedural MR seems to counteract the beneficial effects of PI. Hence, the combined transseptal approach of PI and MCT seems to be the appropriate strategy in patients with significant MR and LVAA.

Percutaneous mitral valve edge-to-edge repair: in-hospital results and 1-year follow-up of 628 patients of the 2011-2012 Pilot European Sentinel Registry

BACKGROUND

The use of transcatheter mitral valve repair (TMVR) has gained widespread acceptance in Europe, but data on immediate success, safety, and long-term echocardiographic follow-up in real-world patients are still limited.

OBJECTIVES

The aim of this multinational registry is to present a real-world overview of TMVR use in Europe.

METHODS

The Transcatheter Valve Treatment Sentinel Pilot Registry is a prospective, independent, consecutive collection of individual patient data.

RESULTS

A total of 628 patients (mean age 74.2 ± 9.7 years, 63.1% men) underwent TMVR between January 2011 and December 2012 in 25 centers in 8 European countries. The prevalent pathogenesis was functional mitral regurgitation (FMR) (n = 452 [72.0%]). The majority of patients (85.5%) were highly symptomatic (New York Heart Association functional class III or higher), with a high logistic EuroSCORE (European System for Cardiac Operative Risk Evaluation) (20.4 ± 16.7%). Acute procedural success was high (95.4%) and similar in FMR and degenerative mitral regurgitation (p = 0.662). One clip was implanted in 61.4% of patients. In-hospital mortality was low (2.9%), without significant differences between groups. The estimated 1-year mortality was 15.3%, which was similar for FMR and degenerative mitral regurgitation. The estimated 1-year rate of rehospitalization because of heart failure was 22.8%, significantly higher in the FMR group (25.8% vs. 12.0%, p[log-rank] = 0.009). Paired echocardiographic data from the 1-year follow-up, available for 368 consecutive patients in 15 centers, showed a persistent reduction in the degree of mitral regurgitation at 1 year (6.0% of patients with severe mitral regurgitation).

CONCLUSIONS

This independent, contemporary registry shows that TMVR is associated with high immediate success, low complication rates, and sustained 1-year reduction of the severity of mitral regurgitation and improvement of clinical symptoms.

Simultaneous double clipping delivery guide strategy for treatment of severe coaptation failure in functional mitral regurgitation

We report on a novel treatment strategy using two clip delivery systems (CDS) simultaneously, after double transseptal puncture, for treatment of severe functional mitral regurgitation. Both CDS were used to titrate for an optimal result in a patient with a severe coaptation gap of both mitral leaflets. The patient was successfully treated with two MitraClips. Thus, even a contraindication for MitraClip can be overcome with a more complex double guide intervention.

Mitral Regurgitation - A Multidisciplinary Challenge

Mitral regurgitation is an increasing valvular disease that represents a difficult management challenge. Surgical treatment for degenerative mitral regurgitation is the standard of care treatment. Percutaneous therapies have emerged rapidly over the past years as an option for treatment of mitral regurgitation for selected, predominantly high-risk patients. Catheter-based devices mimic these surgical approaches with less procedural risk. Mitraclip® implantation mimics the surgical edge-to-edge leaflet repair technique, reducing the regurgitant area. We review the increasing evidence with the Mitraclip device reported to date.