Closed-chest robotic mitral repair using a semi-rigid ring inserted through a trocar.

There are several types of annuloplasty devices for mitral repair. We present a totally-thoracoscopic robotic mitral repair using a new semi-rigid ring with a nitinol core that makes it malleable so that it can be inserted through a trocar. This technique combines the advantages of semi-rigid rings and a totally-thoracoscopic approach, which may further expand this approach to other aetiologies.

5-Year Outcomes of Anterior Mitral Leaflet Laceration to Prevent Outflow Obstruction.

BACKGROUND: Left ventricular outflow tract (LVOT) obstruction is a common, often fatal complication of transcatheter mitral valve replacement (TMVR). Laceration of the anterior mitral leaflet to prevent outflow obstruction (LAMPOON) was safe and effective at preventing LVOT obstruction at 30 days in the National Heart, Lung, and Blood Institute LAMPOON trial. OBJECTIVES: The authors report the 5-year outcomes of intentional anterior mitral leaflet laceration before SAPIEN 3 TMVR, in patients at risk of LVOT obstruction. METHODS: The National Heart, Lung, and Blood Institute LAMPOON trial was a prospective, multicenter, single-arm safety and feasibility study of LAMPOON and transseptal SAPIEN 3 TMVR in annuloplasty rings (valve-in-ring) or native mitral annular calcification (MAC) (valve-in-MAC). All subjects had high predicted risk for LVOT obstruction. Subjects were not excluded for excessive frailty or comorbidity. The primary endpoints were technical success and safety at 30 days. Secondary clinical and echocardiographic endpoints were assessed at 1 year and clinical follow-up at 5 years. RESULTS: Thirty subjects were enrolled between June 2017 and June 2018, equally between the valve-in-MAC and valve-in-ring arms. At 30 days, LAMPOON was successful in all 30 subjects, with no strokes, 1 (3%) death, and 1 (3%) moderate LVOT obstruction. Eighteen (65%) survived to 1 year, and 7 (25%) survived to 5 years. Six (20%) were hospitalized for heart failure in the first year. From baseline to 1 year, there was a 24-point improvement in Kansas City Cardiomyopathy Questionnaire score and a 60-m improvement in 6-minute walk distance. There was no significant change in N-terminal pro-brain natriuretic peptide. At 1 year, LVOT gradients remained low. CONCLUSIONS: LAMPOON enabled TMVR despite the risk for LVOT obstruction. There were no long-term complications associated with LAMPOON. The selection of inoperable patients limited assessment of long-term survival following TMVR. (NHLBI DIR LAMPOON Study: Intentional Laceration of the Anterior Mitral Leaflet to Prevent Left Ventricular Outflow Tract Obstruction During Transcatheter Mitral Valve Implantation; NCT03015194).

The New Era of Three-Dimensional Annuloplasty Devices for Mitral Valve Repair: Rationale and First Experiences.

Annuloplasty should always accompany mitral valve repair in order to achieve proper annular remodeling and stabilization. Numerous types of annuloplasty rings-that differ from rigid to semi-rigid and flexible devices, from complete to partial, and from flat to saddle-shaped rings-are clinically available. A deeper understanding of mitral valve function, in conjunction with several recent studies, suggest it is advisable to prefer annuloplasty rings that mimic the physiological mitral annulus shape and three-dimensional (3D) dynamic changes in order to reduce haemodynamic stress on valve components and optimize leaflet coaptation, perhaps improving valve repair durability too. This paper aims to focus on 3D annuloplasty rings, with dynamic features: MEMO 3D™ and MEMO 4D™ (Sorin Medical, New York, New York), as well as Physio Flex (Edwards Lifesciences, Irvine, California).

Five-year outcomes of mitral valve repair for leaflet prolapse at a medium-sized Norwegian university hospital.

Objective. To evaluate patient characteristics and 5-year outcomes after surgical mitral valve (MV) repair for leaflet prolapse at a medium-sized cardiothoracic center. Background. Contemporary reports on the outcome of MV repair at medium-sized cardiothoracic centers are sparse. Methods. Patients receiving open-heart surgery with MV repair due to primary mitral regurgitation caused by leaflet prolapse between 2015 and 2021, without active endocarditis, were included. Clinical data, complications, re-interventions, mortality, and echocardiographic data were retrospectively registered from electronical patient charts, both pre-operatively and from post-operative follow-ups. Results. One hundred and three patients were included, 83% male, with a mean age of 62 years. All-cause mortality was 9% during a median follow-up time of 4.9 years. Re-intervention rate on the MV was 4%. Post-operative complications before last available follow-up visit at median 3.0 years were infrequent, with new-onset atrial fibrillation/flutter in 16%, post-operative MV regurgitation grade II or above in 17% and post-operative tricuspid regurgitation grade II or above in 14%. Conclusions. These data demonstrate that surgical MV repair for leaflet prolapse at a medium-sized cardiothoracic center was associated with low re-intervention rate and few severe complications. The presented results are comparable to data from surgical high-volume centers, indicating that surgical MV repair can be safely performed at selected medium-sized cardiothoracic centers.

Outcomes after transcatheter mitral valve implantation in valve-in-valve, valve-in-ring, and valve-in-mitral annular calcification.

AIMS: We aimed to evaluate transcatheter mitral valve implantation (TMVI) using predominantly balloon-expandable transcatheter heart valves (THV) in patients with a landing zone for a percutaneously delivered prosthesis. BACKGROUND: Patients with a degenerated mitral valve bioprosthesis, annuloplasty ring, and mitral annulus calcification (MAC) considered at high surgical risk currently represent a treatment challenge. TMVI is an alternative treatment option. METHODS: Retrospective analysis of patients with symptomatic degenerated mitral valve bioprosthesis, or annuloplasty ring, and MAC treated with TMVI between November 2011 and April 2021. Endpoints were defined according to Mitral Valve Academic Research Consortium (MVARC) criteria and included device and procedure success at 30 days as well as mortality at 30 days and 1 year after the procedure. RESULTS: A total of 77 patients underwent TMVI (valve in valve [ViV = 56], valve in ring [ViR = 11], and valve in MAC [ViMAC = 10]). There was a trend toward higher technical success (all = 93.5%, ViV = 96.4%, ViR = 90.9%, ViMAC = 80%, p = 0.06) and lower 30-day (all = 11.7%, ViV = 10.7%, ViR = 9.1%, ViMAC = 20%, p = 0.49) and 1-year mortality (all = 26%, ViV = 23.2%, ViR = 27.3%, ViMAC= 40%, p = 0.36) after ViV and ViR compared to ViMAC. CONCLUSION: TMVI represents a reasonable treatment option in selected patients with MAC or who are poor candidates for redo mitral valve surgery. Technical success and survival up to 1 year were not significantly dependent on the subgroup in which TMVI was performed.

Transcatheter Mitral Valve Repair With the MitraClip Device for Prior Mitral Valve Repair Failure: Insights From the GIOTTO-FAILS Study.

BACKGROUND: Minimally invasive mitral valve repair has a favorable risk-benefit profile in patients with significant de novo mitral regurgitation. Its role in patients with prior mitral valve repair is uncertain. We aimed to appraise the outcome of patients undergoing transcatheter edge-to-edge repair (TEER) with prior transcatheter or surgical mitral valve repair (SMVR). METHODS AND RESULTS: We queried the Italian multicenter registry on TEER with MitraClip, distinguishing naïve patients from those with prior TEER or (SMVR). Inhospital and long-term clinical/echocardiographic outcomes were appraised. The primary outcome was the occurrence of death or rehospitalization for heart failure. A total of 2238 patients were included, with 2169 (96.9%) who were naïve to any mitral intervention, 29 (1.3%) with prior TEER, and 40 (1.8%) with prior SMVR. Several significant differences were found in baseline clinical and imaging features. Respectively, device success was obtained in 2120 (97.7%), 28 (96.6%), and 38 (95.0%, P=0.261) patients; procedural success in 2080 (95.9%), 25 (86.2%), and 38 (95.0%; P=0.047); and inhospital death in 61 (2.8%), 1 (3.5%), and no (P=0.558) patients. Clinical follow-up after a mean of 14 months showed similar rates of death, cardiac death, rehospitalization, rehospitalization for heart failure, and their composite (all P>0.05). Propensity score-adjusted analysis confirmed unadjusted analysis, with lower procedural success for the prior TEER group (odds ratio, 0.28 [95% CI, 0.09-0.81]; P=0.019) but similar odds ratios and hazard ratios for all other outcomes in the naïve, TEER, and SMVR groups (all P>0.05). CONCLUSIONS: In carefully selected patients, TEER can be performed using the MitraClip device even after prior TEER or SMVR.

Non-resectional cordal repair for Barlow mitral valve disease.

BACKGROUND: The redundant leaflet tissue and annular pathology of Barlow disease can make surgical repair challenging. We examined perioperative and late outcomes of a large cohort of patients with Barlow disease undergoing surgical repair. METHODS: Patients included in this analysis underwent mitral valve repair from 01/2004-11/2021 by a single surgeon. RESULTS: Of 2798 patients undergoing mitral valve operations, 46% (N.=1292) had degenerative pathology and 7% (N.=184) had Barlow disease. Of the 179 Barlow patients, median age at surgery was 62 (51-70) years; 64% were male (115/179). Rates of non-resectional cordal repair and resectional repair were 86% (154/179) and 14% (25/179). Among patients undergoing non-resectional repair, the median number of cordal pairs inserted on the anterior and posterior leaflets was 2 (2-3) and 4 (3-4). Incidence of return to bypass for systolic anterior motion of the mitral valve, perioperative death, stroke, and renal failure was 2% (4/179), 1% (2/179), 0% (0/179), and 0% (0/179). Rates of clinical and echocardiographic follow-up were 93% (165/177) and 89% (157/177). Median time to latest postoperative clinical and echocardiographic follow-up was 2.4 (0.8-6.1) and 2.1 (0.6-4.7) years. Mitral regurgitation grade at latest follow-up or time of repair failure was none/trace, mild, mild to moderate, and severe in 63% (98/157), 26% (41/157), 8% (12/157), and 4% (6/157); five of six patients with severe MR underwent reoperation. Since 2011 97% (139/144) of patients underwent cordal repair without resection. CONCLUSIONS: Non-resectional artificial cordal repair is safe and feasible in almost all patients with Barlow valves and is associated with excellent mid-term results.

Proof of Concept: Development of a Mitral Annuloplasty Ring With Crosshatch Net.

OBJECTIVE: Here we report our preclinical, proof-of-concept testing to assess the ability of a novel device to correct mitral regurgitation. The Milwaukee Heart device aims to enable any cardiac surgeon to perform high-quality mitral valve repair using a standard annuloplasty ring with a crosshatch of microporous, monofilament suture. METHODS: Hemodynamic, echocardiographic, and videographic data were collected at baseline, following induction of mitral regurgitation, and after repair using porcine hearts in an ex vivo biosimulator model. A commercially available cardiac prosthesis assessment platform was then used to assess the hydrodynamic characteristics of the study device. RESULTS: Porcine biosimulator pressure and flow metrics exhibited successful correction of mitral regurgitation following device implantation with similar values to baseline. Hydrodynamic results yielded pressure gradients and an effective orifice area comparable to currently approved prostheses. CONCLUSIONS: The study device effectively reduced mitral valve regurgitation and improved hemodynamics in our preclinical model with similar biophysical metrics to currently approved devices. Future in vivo trials are needed to evaluate the efficacy, biocompatibility, and freedom from the most likely adverse events, such as device thrombosis, embolic events, and hemolysis.

Entire Mitral Valve Reconstruction Using Porcine Extracellular Matrix: Adding a Ring Annuloplasty.

PURPOSE: This study investigated the implications of inserting a flexible annuloplasty ring after reconstructing the entire mitral valve in a porcine model using a previously investigated tube graft design made of 2-ply small intestinal submucosa extracellular matrix (CorMatrix®). METHODS: An acute model with eight 80-kg pigs, each acting as its own control, was used. The entire mitral valve was reconstructed with a 2-ply small intestinal submucosa extracellular matrix tube graft (CorMatrix®). Subsequently, a Simulus® flexible ring was inserted. The characterization was based on mitral annular geometry and valvular dynamics with sonomicrometry and echocardiography. RESULTS: After adding the ring annuloplasty, the in-plane annular dynamics were more constant throughout the cardiac cycle compared to the reconstruction alone. However, the commissure-commissure distance was statistically significantly decreased [35.0 ± 3.4 mm vs. 27.4 ± 1.9 mm, P < 0.001, diff = - 7.6 mm, 95% CI, - 9.8 to (-5.4) mm] after ring insertion, changing the physiological annular D-shape into a circular shape which created folds at the coaptation zone resulting in a central regurgitant jet on color Doppler. CONCLUSION: We successfully reconstructed the entire mitral valve using 2-ply small intestinal submucosal extracellular matrix (CorMatrix®) combined with a flexible annuloplasty. The annuloplasty reduced the unphysiological systolic widening previously found with this reconstructive technique. However, the Simulus flex ring changed the physiological annular D-shape into a circular shape and hindered a correct unfolding of the leaflets. Thus, we do not recommend a flexible ring in conjunction with this reconstructive technique; further investigations are needed to discover a more suitable remodelling annuloplasty.

Finite element analysis of mitral valve annuloplasty in Barlow's disease.

Barlow's Disease affects the entire mitral valve apparatus causing mitral regurgitation. Standard annuloplasty procedures lead to an average of 55% annular area reduction of the end diastolic pre-operative annular area in Barlow's diseased valves. Following annular reduction, mitral valvuloplasty may be needed, usually with special focus on the posterior leaflet. An in silico pipeline to perform annuloplasty by utilizing the pre- and -postoperative 3D echocardiographic recordings was developed. Our objective was to test the hypothesis that annuloplasty ring sizes based on a percentage (10%-25%) decrease of the pre-operative annular area at end diastole can result in sufficient coaptation area for the selected Barlow's diseased patient. The patient specific mitral valve geometry and finite element model were created from echocardiography recordings. The post-operative echocardiography was used to obtain the artificial ring geometry and displacements, and the motion of the papillary muscles after surgery. These were used as boundary conditions in our annuloplasty finite element analyses. Then, the segmented annuloplasty ring was scaled up to represent a 10%, 20% and 25% reduction of the pre-operative end diastolic annular area and implanted to the end diastolic pre-operative finite element model. The pre-operative contact area decrease was shown to be dependent on the annular dilation at late systole. Constraining the mitral valve from dilating excessively can be sufficient to achieve proper coaptation throughout systole. The finite element analyses show that the selected Barlow's diseased patient may benefit from an annuloplasty ring with moderate annular reduction alone.

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.

Treatment options for ischemic mitral regurgitation: A meta-analysis.

BACKGROUND: Treatment of ischemic mitral regurgitation (IMR) is in evolution, as percutaneous procedures and complex surgical repair have been recently investigated in randomized clinical trials and matched studies. This study aims to review and compare the current treatment options for IMR. METHODS: A comprehensive literature search was conducted using electronic databases. The primary outcome was all-cause long-term mortality. The secondary outcomes were perioperative mortality, unplanned rehospitalization, reoperation, and composite end points as defined in the original articles. RESULTS: A total of 12 articles met the inclusion criteria and were included in the final meta-analysis. The MitraClip procedure did not confer a significant benefit in mortality and repeated hospitalization compared with medical therapy alone. In patients with moderate IMR, the adjunct of mitral procedure over coronary artery bypass graft is not associated with clinical improvements. When evaluating mitral valve (MV) replacement versus repair, hospital mortality was greater among patients undergoing replacement (odds ratio [OR], 1.91; P = .009), but both reoperation and readmission rates were lower (OR, 0.60, P = .05; and OR, 0.45, P < .02, respectively). Comparing restrictive annuloplasty alone with adjunctive subvalvular repair, subvalvular procedures resulted in fewer readmissions (OR, 0.50; P = .06) and adverse composite end points (P = .009). CONCLUSIONS: MitraClip procedure is not associated with improved outcomes compared with medical therapy. MV replacement is associated with increased early mortality but reduced reoperation rate and readmission rate compared with MV repair using annuloplasty in moderate-to-severe IMR. Despite no significant benefit in isolated outcomes comparing annular and adjunct subvalvular procedures, the adjunct of subvalvular procedures reduces the risk of major postoperative adverse events.

Influences of mitral annuloplasty on left ventricular flow dynamics assessed with 3-dimensional cine phase-contrast flow magnetic resonance imaging.

OBJECTIVES: We assessed the influence of annuloplasty procedures in mitral repair on left ventricular (LV) vortex flow patterns and aortic outflow patterns, and flow energy loss (EL). METHODS: Twenty healthy volunteers and 14 patients who had undergone mitral valve repair were examined using 3-dimensional cine phase-contrast magnetic resonance imaging. A band group included 7 patients with semi-rigid and 2 with flexible partial bands. The ring group included 5 patients with semi-rigid complete rings. LV vortex flow patterns, aortic outflow patterns, EL, and aortic annulus changes during one cardiac cycle were evaluated. RESULTS: Mitral repair induced different vortex flow patterns compared with that of healthy volunteers. The vortex beneath the anterior mitral leaflet with semi-rigid devices was double-stranded in early diastole, and it was single-stranded with flexible bands with a large shift toward the apex during diastole. LVEL in patients who underwent mitral repair (0.84 ± 0.42 mW) was greater than that in healthy volunteers (0.47 ± 0.10 mW). Complete rings disturbed aortic outflow patterns, with EL distribution changes. Smaller devices relative to patient body size disturbed LV flow patterns and caused high EL. No significant relationship was found between indexed ring orifice area and transmitral mean pressure gradient (r = -0.25, P = .414), but a negative relationship exists between indexed ring orifice area and LVEL (r = -0.84, P < .001). CONCLUSIONS: Mitral repair, especially with relatively small annuloplasty rings, induced abnormal LV flow patterns and EL elevation, which have the potential to be a novel hemodynamic evaluation method after mitral repair.

Early and Mid-Term Results After Repair of Ischaemic Mitral Regurgitation with Complete Annuloplasty Ring and Incomplete Ring.

BACKGROUND: The choice of ring type for mitral valve (MV) repair is still debatable and usually is left to the surgeon's discretion. AIM: The aim of this study was to compare the early and mid-term results after repair of ischaemic mitral regurgitation (MR) with complete and incomplete annuloplasty rings. METHODS: Collected data included preoperative assessment (age, sex, comorbidities, clinical status, NYHA grade, and the EURO score); intraoperative details (echocardiography, degree of MR, and cross-clamp time); and results (the length of ICU and hospital stay, duration and need for inotropes, duration of mechanical ventilation, and postoperative adverse events). Follow up after discharge included assessment of dyspnea status, the degree and progression of MR, and left ventricular function and dimensions. RESULTS: The present study included 133 patients: 61 with incomplete rings and 72 with complete rings inserted. There was no significant difference in the rate of postoperative complications between the two groups, apart from a significantly higher percentage of patients with incomplete ring who required prolonged ventilation >24 hours (P = 0.002). There were no significant differences between the two groups, regarding the grade of residual MR (P = 0.464), postoperative dyspnea status (P = 0.723), 30-day mortality rate (P = 0.687), and mean duration of survival (P = 0.276). CONCLUSION: The choice of incomplete or complete annuloplasty ring was not associated with a marked difference in the early and midterm results of ischaemic MV repair.

Mitral valve diseases: Pathophysiology and interventions.

Valvular heart disease is common and increasingly prevalent among the elderly. The end result of valvular pathologies is cardiac failure and can lead to sudden death; thus, diagnosis and interventions are very important in the early stages of these diseases. The usual treatment methods of mitral regurgitation include percutaneous mitral valve repair, mitral valve replacement and minimally invasive surgery, whereas the treatment methods of mitral stenosis include percutaneous transluminal mitral commissurotomy and mitral commissurotomy as well as open surgical repair. Nonetheless, ongoing clinical trials are a clear indicator that the management of valve diseases is ever evolving. The focus of this paper is on the various pathologies of the mitral valve, their etiology and clinical management, offering a comprehensive view of mitral valve diseases.

Comparison of flexible, open with semi-rigid, closed annuloplasty-rings for mitral valve repair.

BACKGROUND: Mitral regurgitation is a frequent valvular disease, with an increasing prevalence. We analysed the long-term outcomes of mitral valve repair procedures conducted over the last 10 years in our clinic using almost exclusively two different annuloplasty ring types. METHODS: A single-centre, retrospective analysis of mitral valve surgeries conducted between January 2005 and December 2015 for patients undergoing first-line mitral valve repair with either open (Cosgrove) or closed (CE Physio / Physio II) annuloplasty (OA or CA, respectively) rings. RESULTS: In total, 1120 patient documentations were available of which 528 underwent OA and 592 patients CA. The median age of patients was 64.0 years and 41.1% were female. The majority of these patients underwent the procedure because of degenerative valve disease. Rates of successful repair were about 90%, 72 h procedural mortality was 0.6% and the rate of re-intervention was 0.6% within the first 30 days. Functional (mitral regurgitation, left ventricular ejection fraction, left ventricular end-diastolic and systolic diameter and New York Heart Association class) as well as hard outcomes were comparable. 77.7 and 74.4% of patients were alive at the 10-year follow-up in the OA and CA groups, respectively. Upon multivariable adjustment, the hazard ratio was 0.926 (95% CI: 0.642-1.3135; p = 0.681). CONCLUSIONS: The functional outcome and survival rates up to 10 years after mitral valve repair were comparable using open and closed annuloplasty rings. Whether this means these rings are interchangeable or a carefully selection of the best-for-the-patient devices will be subject of future investigations.

Percutaneous Mitral Valve Intervention Using MitraClip for Functional Mitral Regurgitation and Heart Failure.

Functional mitral regurgitation (FMR) frequently coexists with left ventricular systolic dysfunction and advanced heart failure, and typically has poor clinical outcomes. Although various therapeutic options including cardiac resynchronization therapy and surgical mitral intervention, have been proposed, an optimal treatment strategy for functional mitral regurgitation has not yet been established. Over the last decade, transcatheter mitral valve repair using MitraClip has emerged as a novel alternative therapeutic option for functional mitral regurgitation. In 2018, the COAPT trial demonstrated that MitraClip treatment reduced rehospitalization due to heart failure and all-cause death in patients with functional mitral regurgitation and heart failure. As a consequence, the MitraClip has become a very promising potential treatment for functional mitral regurgitation. In this review, we discuss and summarize the current status and future perspectives of the treatment for functional mitral regurgitation and heart failure.