Clinical and echocardiographic results of the MEMO 4D semi-rigid annuloplasty ring.

BACKGROUND: Mitral regurgitation is a frequent valvular disease, with an increasing prevalence. We analyzed the short-term outcomes of mitral valve repair procedures conducted in our clinic using a new semirigid annuloplasty ring featuring a gradual saddle shape design. METHODS: We retrospectively analyzed mitral valve repair surgeries performed at our Institution between December 2019 and November 2021 with the MEMO 4D semirigid annuloplasty ring. RESULTS: In total, 53 patients were included in the study. Mean patient age was 63.6 ± 11.7 years. Most patients presented with degenerative mitral valve regurgitation (N = 44; 83%). The grade of mitral regurgitation was equal or more than 3 + in 98.1% of the patients (N = 52). The most used ring size was size 34 mm (N = 30, 56.6%). There was no intraoperative or hospital mortality. No cases of stroke, bleeding, endocarditis or other major complications occurred. At discharge, most patients were in NYHA class I. Postoperative echocardiographic results showed no (90.6%) or 1+ (5.7%) mitral valve regurgitation. Only 1 patient (1.9%) presented with mitral valve regurgitation grade 2+. Mean postoperative transvalvular gradient was low (mean = 3.3 ± 1.2 mmHg). No cases of LVOT obstruction or systolic anterior motion occurred. CONCLUSIONS: Our series showed excellent mitral valve competency and very satisfactory early clinical outcomes. The transesophageal echocardiographic follow-up, despite obtained in a limited number of patients, further confirmed the effectiveness of findings of this preliminary experience.

Does Sustained Reduction of Functional Mitral Regurgitation Impact Survival?

Functional mitral regurgitation (FMR) is associated with increased mortality and has been considered a marker for advanced heart disease, yet the value of mitral valve repair (MVr) in this population remains unclear. This study aims to evaluate the impact of reducing FMR burden through surgical MVr on survival. Patients with severe FMR who underwent MVr with an undersized, complete, rigid, annuloplasty between 2004 and 2017 were assessed (n = 201). Patients were categorized based on grade of recurrent FMR (0-4). Time-to-event Kaplan-Meier estimations of freedom from death or reoperation were performed using the log-rank test. Cox proportional hazards models evaluated all-cause mortality and reported in hazards ratios (HR) and 95% confidence intervals (CI). Patients were categorized by postoperative recurrent FMR: 45% (91/201) of patients had grade 0, 29% (58/201) grade 1, 20% (40/201) grade 2, 2% (4/201) grade 3%, and 4% (8/201) grade 4. The cumulative incidence of reoperation with death as a competing risk was higher in patients with grades ≥3 recurrent FMR compared to grades ≤2 (44.6% vs 14.6%, subhazard ratio 3.69 [95% CI, 1.17-11.6]; P = 0.026). Overall freedom from death or reoperation was superior for recurrent FMR grades ≤2 compared to grades ≥3 (log-rank P < 0.001). Increasing recurrent FMR grade was independently associated with mortality (HR 1.30 [95% CI, 1.07-1.59] P = 0.009). Reduced postoperative FMR grade resulted in an incrementally lower risk of death or reoperation after MVr. These results suggest that achieving a durable reduction in FMR burden improves long-term survival.

The CINCH-FMR postmarket registry: Real-world long-term outcomes with percutaneous mitral valve repair with the Carillon Mitral Contour System®.

BACKGROUND: The Carillon® Mitral Contour System® has been studied in 4 prospective controlled studies in the treatment of functional mitral regurgitation (FMR) where it has been found to reduce mitral regurgitation, reduce left ventricular and atrial volumes, and be associated with improvements in clinical parameters. AIMS: The CINCH post-market registry is designed to evaluate immediate, mid-term and long-term outcomes from a post-approval study of the Carillon® device evaluated in real-world practice. METHODS: The CINCH post-market registry is a single-arm study of percutaneous mitral annuloplasty with the Carillon device in patients with functional (secondary) mitral regurgitation and symptomatic congestive heart failure when utilized in real-world conditions. Patient selection, echocardiographic hemodynamic measurements, and patient follow-up requirements were performed per standard of care at each institution. RESULTS: A total of 101 patients treated with the Carillon device at 13 sites in Germany were enrolled in the CINCH registry. The mean age was 75 ± 9 years, 57 % were male, and patient presentation included primarily NYHA class III (69 %) with MR grade 3 (68 %). Over 5 years of follow-up, all-cause mortality was 40.1 %, the incidence of HFH was 53.9 %, and the composite outcome of HFH or death was 66.4 %. At each follow-up interval through 5 years, statistically significant reductions in NYHA class (p < 0.05) and MR grade (p < 0.01) were reported. CONCLUSIONS: In this "real world" registry of the Carillon Mitral Contour System, procedural safety and medium-term follow-up outcomes is similar to the outcomes seen in the prospective, controlled clinical trials, despite being used in populations of patients that extend outside of those studied in the trials. The use of this therapy in patients with atrial functional mitral regurgitation, and heart failure with preserved ejection fraction, was notable, since these types of patients were excluded from the prospective, controlled trials. This supports possible additional patient populations who might benefit from this type of mechanical therapy. The safety profile of this therapy in this registry and in the earlier trials may support a potential role in earlier forms of secondary mitral regurgitation.

Subannular repair in secondary mitral regurgitation with restricted leaflet motion during systole.

OBJECTIVE: Ventricular secondary mitral regurgitation (SMR) (Carpentier type IIIb) results from left ventricular (LV) remodelling, displacement of papillary muscles and tethering of mitral leaflets. The most appropriate treatment approach remains controversial. We aimed to assess the safety and efficacy of standardised relocation of both papillary muscles (subannular repair) at 1-year follow-up (FU). METHODS: REFORM-MR (Reform-Mitral Regurgitation) is a prospective, multicentre registry that enrolled consecutive patients with ventricular SMR (Carpentier type IIIb) undergoing standardised subannular mitral valve (MV) repair in combination with annuloplasty at five sites in Germany. Here, we report survival, freedom from recurrence of MR >2+, freedom from major adverse cardiac and cerebrovascular events (MACCEs), including cardiovascular death, myocardial infarction, stroke, MV reintervention and echocardiographic parameters of residual leaflet tethering at 1-year FU. RESULTS: A total of 94 patients (69.1% male) with a mean age of 65.1±9.7 years met the inclusion criteria. Advanced LV dysfunction (mean left ventricular ejection fraction 36.4±10.5%) and severe LV dilatation (mean left ventricular end-diastolic diameter 61.0±9.3 mm) resulted in severe mitral leaflet tethering (mean tenting height 10.6±3.0 mm) and an elevated mean EURO Score II of 4.8±4.6 prior to surgery. Subannular repair was successfully performed in all patients, without operative mortality or complications. One-year survival was 95.5%. At 12 months, a durable reduction of mitral leaflet tethering resulted in a low rate (4.2%) of recurrent MR >2+. In addition to a significant improvement in New York Heart Association (NYHA) class (22.4% patients in NYHA III/IV vs 64.5% patients at baseline, p<0.001), freedom from MACCE was observed in 91.1% of patients. CONCLUSIONS: Our study demonstrates the safety and feasibility of standardised subannular repair to treat ventricular SMR (Carpentier type IIIb) in a multicentre setting. By addressing mitral leaflet tethering, papillary muscle relocation results in very satisfactory 1-year outcomes and has the potential to durably restore MV geometry; nevertheless, long-term FU is mandatory. TRIAL REGISTRATION NUMBER: NCT03470155.

Image-based ring size prediction for mitral valve repair.

OBJECTIVES: Annuloplasty rings are routinely used in mitral valve repair (MVr). However, accurate annuloplasty ring size selection is essential to obtain a favourable outcome. Moreover, ring sizing can be challenging in some patients and is highly influenced by surgeons' experience. This study investigated the utility of three-dimensional mitral valve (3D-MV) reconstruction models to predict annuloplasty ring size for MVr. METHODS: A total of 150 patients undergoing minimally invasive MVr with annuloplasty ring due to Carpentier type II pathology and who were discharged with none/trace residual mitral regurgitation were included. 3D-MV reconstruction models were created with a semi-automated software package (4D MV Analysis) to quantitate mitral valve geometry. To predict the ring size, univariable and multivariable linear regression analyses were performed. RESULTS: Between 3D-MV reconstruction values and implanted ring sizes, the highest correlation coefficients were provided by commissural width (CW) (0.839; P < 0.001), intertrigonal distance (ITD) (0.796; P < 0.001), annulus area (0.782; P < 0.001), anterior mitral leaflet area (0.767; P < 0.001), anterior-posterior diameter (0.679; P < 0.001) and anterior mitral leaflet length (0.515; P < 0.001). In multivariable regression analysis, only CW and ITD were found to be independent predictors of annuloplasty ring size (R2 = 0.743; P < 0.001). The highest level of agreement was achieved with CW and ITD, and 76.6% of patients received a ring with no >1 ring size difference from the predicted ring sizes. CONCLUSIONS: 3D-MV reconstruction models can support surgeons in the decision-making process for annuloplasty ring sizing. The present study may be a first step towards accurate annuloplasty ring size prediction using multimodal machine learning decision support.

Mitral valve repair with the use of the "Memo 3D ReChord" ring.

BACKGROUND: From a variety of ring types, semirigid ring is more preferred for mitral annuloplasty during mitral valve repair particularly in patients whose native mitral saddle shape annulus is well maintained. During mitral annuloplasty artificial chord implantation with the appropriate neochord length is surgically challenging. We present our experience of using the Memo 3D ReChord, a semirigid ring with additional chordal guiding system for mitral valve repair. PATIENTS AND METHODS: From September 2018 to February 2020, we successfully treated ten patients with severe (4+/4+) degenerative mitral valve regurgitation due to posterior leaflet prolapse with chordal rupture with the implantation Memo 3D ReChord and neo-chords. RESULTS: We implanted from one to three neo-chords and always a ring in our patients. None of the patients had any residual mitral valve regurgitation at the end of the repair and on their discharge evaluated through transesophageal and transthoracic echocardiography respectively. There was no mortality at 30-days or on midterm follow-up. During the 3-month follow-up no regurgitation was noticed either. We included in our study only the patients successfully treated. We also used it in two patients, who underwent valve replacement during the same operation due to mild to moderate mitral valve regurgitation. CONCLUSIONS: This, in our knowledge, is the first Greek series of the implantation of the Memo 3D Rechord. The initial excellent results give us the enthusiasm to continue while long-term results and the durability of this technique are necessary to establish this semirigid annuloplastic ring in our every-day practice.

Data-driven mortality risk prediction of severe degenerative mitral regurgitation patients undergoing mitral valve surgery.

AIMS: The outcomes of mitral valve replacement/repair (MVR) in severe degenerative mitral regurgitation (MR) patients depend on various risk factors. We aimed to develop a risk prediction model for post-MVR mortality in severe degenerative MR patients using machine learning. METHODS AND RESULTS: Consecutive severe degenerative MR patients undergoing MVR were analysed (n = 1521; 70% training/30% test sets). A random survival forest (RSF) model was constructed, with 3-year post-MVR all-cause mortality as the outcome. Partial dependency plots were used to define the thresholds of each risk factor. A simple scoring system (MVR-score) was developed to stratify post-MVR mortality risk. At 3 years following MVR, 90 patients (5.9%) died in the entire cohort (59 and 31 deaths in the training and test sets). The most important predictors of mortality in order of importance were age, haemoglobin, valve replacement, glomerular filtration rate, left atrial dimension, and left ventricular (LV) end-systolic diameter. The final RSF model with these six variables demonstrated high predictive performance in the test set (3-year C-index 0.880, 95% confidence interval 0.834-0.925), with mortality risk increased strongly with left atrial dimension >55 mm, and LV end-systolic diameter >45 mm. MVR-score demonstrated effective risk stratification and had significantly higher predictability compared to the modified Mitral Regurgitation International Database score (3-year C-index 0.803 vs. 0.750, P = 0.034). CONCLUSION: A data-driven machine learning model provided accurate post-MVR mortality prediction in severe degenerative MR patients. The outcome following MVR in severe degenerative MR patients is governed by both clinical and echocardiographic factors.

Predictors of mitral valve haemodynamics after mitral valve repair for degenerative mitral regurgitation.

OBJECTIVE: Intraoperative predictors of functional mitral valve (MV) stenosis after surgical repair of mitral regurgitation (MR) caused by prolapse remain poorly characterised. This study evaluated the effect of annuloplasty size on postoperative MV haemodynamics during exercise and evaluated predictors of MV hemodynamics. METHODS: 104 patients were randomly assigned to leaflet resection or preservation for surgical repair of MR in the Canadian Mitral Research Alliance CardioLink-2 study. In this post hoc analysis, we compared MV haemodynamics between the two surgical groups and examined the relationship between annuloplasty size and MV haemodynamics 1 year after repair in the combined groups. Echocardiograms were performed at baseline and intraoperatively. Exercise transthoracic echocardiography was performed 1 year postoperatively. Multivariable linear regression analysis was used to identify predictors of exercise MV gradients at follow-up. RESULTS: Mean age of participants was 65±10 years, and 83% were male. Median annuloplasty size was 34 (IQR 32-36). Dividing by the median, 48 (46%) had annuloplasty size of <34 mm and 56 (54%) had ≥34 mm. Mean and peak exercise gradients at 1 year were 11±5 mm Hg and 22±9 mm Hg in <34, and 6±3 mm Hg and 14±5 mm Hg in ≥34 (p<0.001). Rate of residual MR was similar in both groups. In multivariable analyses, annuloplasty size of ≥34 mm was associated with lower mean and peak exercise gradients at 12 months, after adjustment for repair type, age, sex, heart rate and body surface area (ß -4.1, 95% CI -6 to -3, p<0.001, and ß -7 95% CI -10 to -4, p<0.001, respectively). Intraoperative mean and peak MV gradients by transesophageal echocardiography independently predicted mean and peak resting and exercise gradients at follow-up (p<0.001). Similar results were obtained in both leaflet resection and preservation. CONCLUSION: Annuloplasty size of ≥34 mm is associated with a 4 and 7 mm Hg reduction in mean and peak exercise MV gradients, respectively, 1 year post MV repair regardless of the repair strategy used. Intraoperative TEE MV gradients predict exercise MV gradients 1 year post repair. TRIAL REGISTRATION NUMBER: NCT02552771.

Risk Factors for Postrepair Elevated Mitral Gradient: A Post-hoc Analysis of a Randomized Trial.

BACKGROUND: Predischarge elevated mean mitral gradients (>5 mm Hg) may occur after repair for degenerative mitral regurgitation. We sought to identify risk factors associated with elevated gradients and to evaluate its impact on functional outcomes at 12 months in this subanalysis of the Canadian Mitral Research Alliance CardioLink-2 trial. METHODS: One hundred four patients with degenerative mitral regurgitation undergoing mitral repair were randomized to either a leaflet resection or preservation strategy. Logistic regression was used to identify risk factors associated with an elevated gradient. Functional outcomes at 12 months were compared between participants with and without elevated gradients. RESULTS: Elevated gradients was identified in 15 participants (14.4%), which was not significantly different based on allocation to each repair strategy (P = .10). Patients with elevated gradients were more likely to be women (odds ratio [OR], 4.28; 95% confidence interval [CI], 1.29-14.19; P = .02) and to have a lower preoperative hemoglobin level (OR, 0.93; 95% CI, 0.89-0.98; P = .01) and smaller intercommissural diameter (OR, 0.86; 95% CI, 0.76-0.97; P = .02) and mitral annuloplasty size (OR, 0.71; 95% CI, 0.57-0.87; P = .001). The ratio of intercommissural diameter-to-annuloplasty size was similar between those with and without elevated gradients (both 0.8 ± 0.1, P = .69). At 12 months those with elevated gradients had a worse New York Heart Association functional status (P = .0001), lower peak oxygen saturation in exercise test (P = .01), smaller body weight-walk distance product (P = .02), and higher Borg scale (P = .01) in the 6-minute walk test. CONCLUSIONS: Female gender, smaller mitral anatomy sizes, and lower preoperative hemoglobin levels were associated with postoperative elevated mitral gradients, which was in turn were associated with reduced functional status. Further research is warranted to investigate these potential risk factors.

Effect of Left Ventricular Hyperenhancement in Magnetic Resonance Imaging on Reverse Remodeling After Mitral Valve Repair for Moderate Ischemic Mitral Regurgitation.

We aimed to investigate cardiac magnetic resonance imaging (MRI)-derived predictors of a lack of left ventricular (LV) reverse remodeling after undersized mitral annuloplasty (uMAP) for moderate ischemic mitral regurgitation (IMR). We retrospectively reviewed 31 patients who underwent uMAP for moderate IMR and cardiac MRI evaluation between 2004 and 2017. Cardiac MRI evaluation included cine MRI LV and right ventricular volumetric measurements and gadolinium-enhanced MRI assessment of myocardial scarring. LV dimensions were assessed preoperatively, postoperatively, and at follow-up using serial transthoracic echocardiography, and the mid-term (median, 49 months) predictors of a lack of LV reverse remodeling were analyzed. At the mid-term follow-up (mean follow-up period: 85 ± 40 months), 15 patients exhibited reverse LV remodeling. The relative reduction in LV dimension at follow-up was negatively correlated with the preoperative number of LV segments with myocardial infarction (MI) (defined as an LV segment with >25% enhancement). The optimal cut-off for predicting a lack of reverse LV remodeling at follow-up was >5 LV segments with MI, with a sensitivity and specificity of 92% and 92%, respectively. This cut-off value also predicted all-cause mortality at follow-up, with a sensitivity and specificity of 88% and 67%, respectively. The presence of >5 LV segments with MI on gadolinium-enhanced MRI might be a useful predictor of lack of reverse LV remodeling and all-cause mortality outcomes after undersized mitral annuloplasty for moderate IMR.

Left ventricle-mitral valve ring size mismatch following ring annuloplasty for nonischemic dilated cardiomyopathy.

BACKGROUND: In patients with ischemic mitral regurgitation (MR) undergoing restrictive mitral annuloplasty (RMA), the ratio of left ventricular (LV) end-systolic dimension (LVESD) to mitral valve (MV) ring size (ie, LV-MV ring mismatch) is associated with postoperative recurrent MR. However, the impact of LV-MV ring mismatch on postoperative recurrent MR, LV function recovery, and long-term survival in patients with nonischemic dilated cardiomyopathy (DCM) remains unknown. METHODS: Sixty-six patients with nonischemic DCM (mean LVESD, 62 mm) underwent RMA (mean ring size, 26 mm) between 2003 and 2014. Recurrent MR was defined as MR grade ≥2+ at a 6-month echocardiographic evaluation. RESULTS: At the 6-month follow-up, 23 patients (35%) had developed recurrent MR. In univariable logistic regression analysis, larger LVESD (P = .012) and LVESD/ring size ratio (P = .008) were associated with recurrent MR. In multivariable models adjusted for age, sex, baseline LV ejection fraction, and severe MR, only LVESD/ring size ratio (odds ratio, 4.65; 95% confidence interval, 1.04-25.0; P = .048) remained significantly associated with MR recurrence. Receiver operating characteristic curve analysis demonstrated an optimal cutoff value for the LVESD/ring size ratio of 2.42. Patients with an LVESD/ring size ratio >2.42 (n = 30; mismatch) had a lower 5-year cumulative survival rate compared with those with an LVESD/ring size ratio ≤2.42 (n = 36; nonmismatch) (52% vs 71%; P = .045). Postoperatively, LV dimensions were significantly reduced in both groups; however, improvements in LVEF were only modest in the mismatched group (P = .091). CONCLUSIONS: LV-MV ring size mismatch was associated with an increased risk of recurrent MR in our series. This finding may aid the formulation of surgical strategies for patients with nonischemic DCM.

Mitral repair of myxomatous valves with simple annuloplasty: a follow-up up to 12 years.

OBJECTIVES: Diffuse myxomatous mitral valve degeneration (DMD) represents a challenge in the reparative mitral valve surgery. A subgroup of patients with symmetrical DMD can be effectively treated with a simple band-annuloplasty with good early and mid-term results. Here, we evaluate the long-term outcomes in terms of freedom from reoperation, recurrence of moderate or severe mitral regurgitation (MR) and overall survival. METHODS: Between April 2006 and December 2020, patients with DMD causing severe MR and the echocardiographic features of symmetrical bileaflet prolapse, central regurgitant jet(s), annular dilation and no chordal ruptures were treated using a simple annuloplasty with a semi-rigid band. These patients were prospectively collected and retrospectively analysed. RESULTS: Seventy-five patients were enrolled. The mean clinical follow-up time was 104 [standard deviation (SD): 43] months, and echocardiographic follow-up time was 95 (SD: 43) months. The mean age was 54 (SD: 15) years, and 56% were females. Long-term overall survival was 98.2% [standard error (SE): 1.8], 93.7% (SE: 4.7) and 93.7% (SE: 4.7) at 4, 8 and 12 years, respectively. The freedom from reoperation was 100% at 4 and 8 years and 94.1% (SE: 5.7) at 12 years. The freedom from recurrent moderate or severe MR was 98.3% (SE: 1.7), 98.3% (SE: 1.7) and 92.8% (SE: 5.5) at 4, 8 and 12 years, respectively. CONCLUSIONS: Mitral repair with the simple band-annuloplasty for the treatment of MR due to symmetrical DMD seems to be stable and effective in the long term.

Acquired left ventricular-right atrial communication after mitral valve replacement and tricuspid annuloplasty.

A 77-year-old woman underwent mitral valve replacement and tricuspid annuloplasty for severe mitral stenosis and tricuspid regurgitation with pulmonary hypertension. Two months later, the patient was readmitted because of marked edema. A new harsh pansystolic murmur was auscultated, and echocardiography revealed a jet from the left ventricle to the right atrium but no paravalvular leakage was detected at the mitral valve position. At operation, an 6 mm defect adjacent to the tricuspid annulus in the interatrial septum and detachment of the anterior edge of the tricuspid ring were detected. The defect was closed using a pericardial patch. An inadequate stitch at the anteroseptal commissure in the previous operation led to left ventricular-right atrial communication.

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.