Effect of Recurrent Mitral Regurgitation Following Degenerative Mitral Valve Repair: Long-Term Analysis of Competing Outcomes

Late results of chord transfer and other techniques for anterior leaflet repair without neochords

OBJECTIVE

Anterior and bileaflet degenerative mitral regurgitation repairs are challenging. We examined our early and late outcomes for repair using 4 techniques, without neochord repair.

METHODS

Between February 1, 2006, and June 30, 2021, a total of 2368 patients received mitral valve ± other surgery by 1 surgeon, including 1160 with degenerative mitral regurgitation. Clinical follow-up was conducted annually (mean 6.8 ± 4.4 years).

RESULTS

Repair was performed in 1137 patients (98%) (mean age, 60.5 ± 11.9 years). Repair rate varied between groups: 99% for isolated posterior leaflet (794/799), 91% for isolated anterior leaflet (83/91), and 96% for bileaflet prolapse (260/270; P < .001). Thirty-day mortality was 0.2%. On a scale of 0 to 4+ mitral regurgitation, mean mitral regurgitation grade decreased from 3.8 ± 0.6 preoperatively to 0.07 ± 0.3 at discharge, including moderate (2+) in 0.6% (7/1137) overall and 0.9% (3/343) with anterior prolapse. None were more than 2+ at discharge. Among the 3 groups of leaflet prolapse, there was no significant difference in long-term survival (P = .26), freedom from mitral valve reintervention (P = .12; 99.4% overall), and freedom from more than moderate (2+) mitral regurgitation (P = .16; 98.3% overall). The 4 most common anterior leaflet repair techniques (chord transfer 17%; commissuroplasty 10%; Alfieri [edge-to-edge] 6%); ring with posterior resection (4.3%) had similar freedom from 10-year reintervention (99.4%, 94%, 100%, and 100%, respectively; P = .29).

CONCLUSIONS

Complex anterior leaflet prolapse repairs are successful using a variety of techniques without neochord implantation. Although neochords are popular, there are other ways to repair complex valves that do not require as much judgment and experience.

Socioeconomic disparities in midterm outcomes after repair for degenerative mitral regurgitation

OBJECTIVE

The influence of socioeconomic disparities on survival after mitral repair is poorly defined. We examined the association between socioeconomic disadvantage and midterm outcomes of repair in Medicare beneficiaries with degenerative mitral regurgitation.

METHODS

US Centers for Medicare and Medicaid Services data were used to identify 10,322 patients undergoing isolated first-time repair for degenerative mitral regurgitation between 2012 and 2019. Zip code-level socioeconomic disadvantage was dichotomized with the Distressed Communities Index, which incorporates education level, poverty, unemployment, housing security, median income, and business growth; those with Distressed Communities Index score ≥80 were classified as distressed. The primary outcome was survival, censored at 3 years. Secondary outcomes included cumulative incidences of heart failure readmission, mitral reintervention, and stroke.

RESULTS

Of the 10,322 patients undergoing degenerative mitral repair, 9.7% (n = 1003) came from distressed communities. Patients from distressed communities underwent surgery at lower volume centers (11 vs 16 cases/year) and traveled further for surgical care (40 vs 17 miles) (both P values < .001). At 3 years, unadjusted survival (85.4%; 95% CI, 82.9%-87.5% vs 89.7%; 95% CI, 89.0%-90.4%) and cumulative incidence of heart failure readmission (11.5%; 95% CI, 9.6%-13.7% vs 7.4%; 95% CI, 6.9%-8.0%) were worse in patients from distressed communities (all P values < .001), whereas mitral reintervention rates were similar (2.7%; 95% CI, 1.8%-4.0% vs 2.8%; 95% CI, 2.5%-3.2%; P = .75). After adjustment, community distress was independently associated with 3-year mortality (hazard ratio, 1.21; 95% CI, 1.01-1.46) and heart failure readmissions (hazard ratio, 1.28; 95% CI, 1.04-1.58).

CONCLUSIONS

Community-level socioeconomic distress is associated with worse outcomes in degenerative mitral repair among Medicare beneficiaries.

Successful transcatheter edge-to-edge repair for atrial functional mitral regurgitation after surgical annuloplasty ring dehiscence: a case report

Background

Annuloplasty ring dehiscence (ARD) after surgical mitral valve repair is a rare complication, which causes recurrent mitral regurgitation (MR) and is associated with adverse outcomes in patients with a prohibitive risk of repeat surgery. However, a patient developed severe MR, when challenging transcatheter edge-to-edge repair (TEER) after surgical ring dehiscence, it should be considering the relative efficacy and safety.

Case summary

An 89-year-old man underwent mitral valve repair with an annuloplasty ring for moderate atrial functional MR (AFMR). Post-operative transthoracic echocardiography on Day 7 suggested a dislodged mitral annuloplasty ring and recurrent moderate AFMR. However, the MR developed severely, which led to two hospitalizations for congestive heart failure in the past year. Transoesophageal echocardiography (TOE) was performed carefully to ensure that the TEER clip did not interfere with the dislodged annuloplasty ring. Consequently, only the therapeutic target on the medial side of the A2-P2 region was approached posteriorly behind the peri-ring space, without gripper interference.

Discussion

Transcatheter edge-to-edge repair using the G4-MitraClip® system is feasible and safe in patients with recurrent severe AFMR after surgical mitral valve repair concomitant with ARD. Meticulous simulation with pre-operative TOE is one of the crucial steps for successful outcomes.

Case Report: Allograft aortic valve replacement in irreparable infant mitral valve

This case report describes a 3-month-old male infant diagnosed with severe mitral stenosis (MS) and mitral regurgitation (MR) by transthoracic echocardiography. The male infant initially underwent complex mitral valve repair surgery. However, postoperative deterioration occurred with hemodynamic instability and shock, necessitating multiple resuscitation efforts and ultimately requiring support from Extracorporeal Membrane Oxygenation (ECMO). Given the serious conditions, the cardiac team decided to perform mitral valve replacement with a fresh allograft aortic valve. Postoperatively, the patient was promptly weaned off ECMO support, and the valve demonstrated sustained functionality throughout the long-term follow-up.

Surgical outcome of mitral valve surgery in atrial functional mitral regurgitation compared with degenerative etiology

OBJECTIVE

To analyze and compare the outcomes of mitral valve surgery for atrial functional mitral regurgitation (AFMR) and for degenerative mitral regurgitation (DMR).

METHODS

Patients with AFMR or DMR who underwent mitral valve repair/replacement at 2 institutions between January 2012 and December 2022 were included. Patients <18 years of age and patients undergoing concomitant cardiac surgery (except for the maze procedure or tricuspid annuloplasty) were excluded. Propensity score analysis was used to adjust for baseline differences.

RESULTS

A total of 642 patients were enrolled. After propensity score analysis, 164 patients were classified into the DMR group, and 82 patients were classified into the AFMR group. All matched patients in both groups had atrial fibrillation. In DMR and AFMR, the 5-year freedom from readmission for heart failure and cardiac death was 96.3% in the DMR group versus 88.6% in the AFMR group (P = .045) and freedom from readmission for cardiac death in the 2 groups was 100% and 90.0%, respectively (P = .002). The recurrence rate of significant mitral regurgitation (MR) after mitral valve repair was not significantly different between the 2 groups (P = .699, log-rank test), and the 5-year freedom from MR recurrence (moderate or greater) was 89.8% and 93.0%, respectively. After the maze procedure, significantly more patients in the AFMR group than the DMR group were in junctional rhythm (49.1% vs 3.3%; P < .001) and required permanent pacemaker insertion during the follow-up period (11.4% vs 1.5% after 5 years; P = .041, log-rank test).

CONCLUSIONS

AFMR was associated with acceptable outcomes of mitral valve surgery, and mitral valve repair is a good treatment option. However, significantly more patients were in junctional rhythm after the maze procedure, needing more permanent pacemaker insertion.

First-in-Man Study of a Novel, Balloon-Adjustable Mitral Annuloplasty Ring

Objectives: Mitral valve repair is the current standard approach for mitral valve regurgitation. However, patients suffering from functional mitral regurgitation have a significant risk of recurrent regurgitation. Adjustable mitral rings may provide a solution for this adverse event. Methods: A single-center, first-in-man clinical study was performed on patients suffering from mitral valve regurgitation. Patients were implanted with the study ring and followed for six months. A balloon catheter can be inserted into the study ring frame at any time after implantation and inflated independently in the areas P1, P2, or P3, which reduces the anterior-posterior diameter. Results: Five patients (75.4 ± 6.1 years; EuroSCORE II 2.1 ± 0.9%; three female) were successfully implanted. Mechanisms of mitral regurgitation were prolapse of the P2-segment in three patients and annular dilation in two patients. Surgical implantation according to the protocol was feasible and is described herein. Median cardiopulmonary bypass time and cross clamp time were 105 (118; 195) and 94 (90; 151) min, respectively. The median intensive care unit stay was 2 (2; 3) days. No perioperative, 30-day, or 6-month mortality was observed, and the repair was stable without residual or recurrent regurgitation ≥ grade 2. All patients reached the primary endpoint without device-related morbidity. Conclusions: Successful implantation was completed in five patients without device-related adverse events. Ring implantation was safe and feasible for all patients. The opportunity of post-implant adjustment to improve leaflet coaptation is a promising new therapeutic strategy that is assessed in a phase II study.

Fiberscope-Based Measurement of Coaptation Height for Intraoperative Assessment of Mitral Valve Repair

BACKGROUND

Restoring adequate coaptation height is a key principle of mitral valve (MV) repair. This study aimed to evaluate the utility of fiberscope (FS) technology to assess MV coaptation height for intraoperative use.

METHODS

Ex-vivo testing was performed on five adult porcine hearts. The left atrium (LA) was resected, and the left ventricle (LV) was pressurized retrograde to 27 ± 1mm Hg. An endoscope was inserted into the LV apex, centered under the MV orifice. An FS system (Milliscope II camera, LED light source, and 0.7 mm diameter × 15 cm long) 90° semirigid scope with 1.2 mm focal length) was mounted above the MV annulus in a custom alignment and measuring fixture. Three blinded measurements were taken at two locations on each MV, A2 and P2 segment, from the top of coaptation to the leaflet edge identified by the FS. Accurate positioning was verified using the LV endoscope. A control (metal rod of similar thickness) was used for comparison, with coaptation height recorded when the control was seen via the endoscope.

RESULTS

Coaptation heights were similar for the control and FS methods across all hearts at A2 (11.6 ± 2.6 mm control vs 11.8 ± 2.2 mm FS) and P2 (13.3 ± 2.6 mm control vs 13.4 ± 2.9 mm FS) segments, with similar measurement variability (control SD 0.1-1.0 mm; FS SD 0.1-0.9 mm). One outlier was excluded from analysis (n = 19/20). The maximum absolute difference and percent error between measurement methods were less than 1.1 mm (median [IQR], 0.6 [0.3-0.9] mm) and less than 14% (4.1 [2.2-7.6]%).

CONCLUSIONS

Utilization of a miniaturized FS enabled precise and accurate quantification of MV coaptation. This technique is promising for evaluating post-repair valve competence and coaptation height.

Echocardiographic Outcomes With Transcatheter Edge-to-Edge Repair for Degenerative Mitral Regurgitation in Prohibitive Surgical Risk Patients

BACKGROUND

The CLASP IID randomized trial (Edwards PASCAL TrAnScatheter Valve RePair System Pivotal Clinical Trial) demonstrated the safety and effectiveness of the PASCAL system for mitral transcatheter edge-to-edge repair (M-TEER) in patients at prohibitive surgical risk with significant symptomatic degenerative mitral regurgitation (DMR).

OBJECTIVES

This study describes the echocardiographic methods and outcomes from the CLASP IID trial and analyzes baseline variables associated with residual mitral regurgitation (MR) ≤1+.

METHODS

An independent echocardiographic core laboratory assessed echocardiographic parameters based on American Society of Echocardiography guidelines focusing on MR mechanism, severity, and feasibility of M-TEER. Factors associated with residual MR ≤1+ were identified using logistic regression.

RESULTS

In 180 randomized patients, baseline echocardiographic parameters were well matched between the PASCAL (n = 117) and MitraClip (n = 63) groups, with flail leaflets present in 79.2% of patients. Baseline MR was 4+ in 76.4% and 3+ in 23.6% of patients. All patients achieved MR ≤2+ at discharge. The proportion of patients with MR ≤1+ was similar in both groups at discharge but diverged at 6 months, favoring PASCAL (83.7% vs 71.2%). Overall, patients with a smaller flail gap were significantly more likely to achieve MR ≤1+ at discharge (adjusted OR: 0.70; 95% CI: 0.50-0.99). Patients treated with PASCAL and those with a smaller flail gap were significantly more likely to sustain MR ≤1+ to 6 months (adjusted OR: 2.72 and 0.76; 95% CI: 1.08-6.89 and 0.60-0.98, respectively).

CONCLUSIONS

The study used DMR-specific echocardiographic methodology for M-TEER reflecting current guidelines and advances in 3-dimensional echocardiography. Treatment with PASCAL and a smaller flail gap were significant factors in sustaining MR ≤1+ to 6 months. Results demonstrate that MR ≤1+ is an achievable benchmark for successful M-TEER. (Edwards PASCAL TrAnScatheter Valve RePair System Pivotal Clinical Trial [CLASP IID]; NCT03706833).

Valvular heart disease: from mechanisms to management

Valvular heart disease is common and its prevalence is rapidly increasing worldwide. Effective medical therapies are insufficient and treatment was historically limited to the surgical techniques of valve repair or replacement, resulting in systematic underprovision of care to older patients and those with substantial comorbidities, frailty, or left ventricular dysfunction. Advances in imaging and surgical techniques over the past 20 years have transformed the management of valvular heart disease. Better understanding of the mechanisms and causes of disease and an increasingly extensive and robust evidence base provide a platform for the delivery of individualised treatment by multidisciplinary heart teams working within networks of diagnostic facilities and specialist heart valve centres. In this Series paper, we aim to provide an overview of the current and future management of valvular heart disease and propose treatment approaches based on an understanding of the underlying pathophysiology and the application of multidisciplinary treatment strategies to individual patients.

A complexity evaluation system for mitral valve repair based on preoperative echocardiographic and machine learning

BACKGROUND

To develop a novel complexity evaluation system for mitral valve repair based on preoperative echocardiographic data and multiple machine learning algorithms.

METHODS

From March 2021 to March 2023, 231 consecutive patients underwent mitral valve repair. Clinical and echocardiographic data were included in the analysis. The end points included immediate mitral valve repair failure (mitral replacement secondary to mitral repair failure) and recurrence regurgitation (moderate or greater mitral regurgitation [MR] before discharge). Various machine learning algorithms were used to establish the complexity evaluation system.

RESULTS

A total of 231 patients were included in this study; the median ejection fraction was 66% (63-70%), and 159 (68.8%) patients were men. Mitral repair was successful in 90.9% (210 of 231) of patients. The linear support vector classification model has the best prediction results in training and test cohorts and the variables of age, A2 lesions, leaflet height, MR grades, and so on were risk factors for failure of mitral valve repair.

CONCLUSION

The linear support vector classification prediction model may allow the evaluation of the complexity of mitral valve repair. Age, A2 lesions, leaflet height, MR grades, and so on may be associated with mitral repair failure.

Effects of mitral valve repair on valvular geometry and hemodynamics in dogs with myxomatous mitral valve disease

OBJECTIVE

To investigate the effects of mitral valve repair on the geometry of the mitral valve complex, hemodynamics, and cardiac function of dogs with myxomatous mitral valve disease (MMVD).

STUDY DESIGN

Retrospective cohort study.

SAMPLE POPULATION

Dogs (n = 77) with stage C MMVD undergoing mitral valve repair under cardiopulmonary bypass.

METHODS

Mitral valve geometry and cardiac function were assessed using echocardiography preoperatively, 1 week postoperatively and 3 months postoperatively.

RESULTS

The coaptation length (0 [0-0] vs. 7 [6-8.5] mm, p < .001) and forward stroke volume index (1.5 ± 0.4 vs. 2.3 ± 0.6 mL/kg, p < .001) were higher at 3-months postoperatively than preoperatively, whereas the vertebral heart score (12.3 ± 1.2 vs. 10.8 ± 0.8 V, p < .001), left atrial-to-aortic ratio (2.2 ± 0.7 vs. 1.2 ± 0.3, p < .001), peak velocity of early diastolic transmitral flow (144 ± 34 vs. 91 ± 18 cm/s, p < .001), and regurgitant volume index (11.3 [8.2-14.0] vs. 1.6 [0.95-2.35] mL/kg, p < .001) were lower. Postoperatively, mitral valve geometry was completely changed within 1 week, whereas changes in vertebral heart score lasted for 3 months.

CONCLUSION

Mitral valve repair changed valvular geometry and improved hemodynamics as assessed by follow-up echocardiography.

CLINICAL SIGNIFICANCE

This study acts as reference for surgeons and cardiologists considering or evaluating the effects of mitral valve repair in dogs and provides useful data for the enhancement of relevant surgical techniques and the selection of relevant pre- and postoperative observations.

Reoperation after early and late failure of mitral valve repair for degenerative disease

OBJECTIVES

To determine mechanisms of early and late failure after mitral valve repair for degenerative disease, identify factors associated with re-repair, and evaluate durability of re-repair.

METHODS

From January 2008 to July 2020, 330 reoperations were performed for recurrent mitral valve dysfunction after initial valve repair for degenerative disease. Mechanisms of repair failure were determined by review of preoperative imaging and operative reports. Multivariable analysis was performed to identify factors associated with likelihood of re-repair or replacement. Durability of re-repair was assessed using longitudinal analysis of postoperative echo data.

RESULTS

Eighty-five of 330 (26%) reoperations were performed for early repair failure within 1 year and 245/330 (74%) for late failure thereafter. Suture/annuloplasty dehiscence, systolic anterior motion, hemolysis, and ventricular remodeling were more common mechanisms of early failure and disease progression and fibrosis late failure. Forty percent (34/85) of early failures were re-repaired versus 24% (59/245) of late failures. Re-repair was more common than replacement in recent years and was associated with earlier reoperation (median 1.5 vs 3.9 years; P = .0001). No in-hospital deaths occurred after re-repair; 2 patients (0.8%) died after valve replacement. Freedom from severe mitral regurgitation after re-repair was 93% at 7 years.

CONCLUSIONS

Mitral valve re-repair can be performed with low rates of mortality and morbidity for early and late valve dysfunction. Mechanisms of early repair failure differ from those of late failure and are generally more amenable to re-repair. In selected patients who present after failed repair, we prefer mitral re-repair to valve replacement whenever technically feasible.

Robotic degenerative mitral repair: Factors associated with intraoperative revision and impact of mild residual regurgitation

OBJECTIVES

National registry data show wide variability in degenerative mitral repair rates and infrequent use of intraoperative repair revision to eliminate residual mitral regurgitation (MR). The consequence of uncorrected mild residual MR is also not clear. We identified factors associated with intraoperative revision of degenerative mitral repair and evaluated long-term effects of intraoperative mild residual MR.

METHODS

A prospective institutional registry of 858 patients with degenerative MR undergoing robotic mitral surgery was linked to statewide databases. Univariate logistic regression identified factors associated with intraoperative repair revision. Survival was estimated using the Kaplan-Meier method and adjusted with Cox regression. Late freedom from more-than-moderate MR or reintervention was estimated with death as a competing risk.

RESULTS

Repair rate was 99.3%. Repair was revised intraoperatively in 19 patients and was associated with anterior or bileaflet prolapse, adjunctive repair techniques, and annuloplasty band size (all P < .05). Intraoperative repair revision did not result in increased postoperative complications. Intraoperative mild residual MR (n = 111) was independently associated with inferior 8-year survival (hazard ratio, 2.97; 95% CI, 1.33-6.23), worse freedom from more than moderate MR (hazard ratio, 3.35; 95% CI, 1.60-7.00), and worse freedom from mitral reintervention (hazard ratio, 6.40; 95% CI, 2.19-18.72) (all P < .01).

CONCLUSIONS

A near 100% repair rate with acceptable durability may be achieved safely with intraoperative revision of postrepair residual MR. Mild residual MR was independently associated with reduced survival, worse freedom from more-than-moderate MR, and worse freedom from mitral reintervention at 8-year follow-up.

Surgical Considerations for the Mitral Valve in Congenitally Corrected Transposition

BACKGROUND

Systemic atrioventricular valve (morphologic tricuspid valve [TV]) regurgitation has been implicated in the development of systemic ventricular failure in congenitally corrected transposition of the great arteries (ccTGA), leading to timely referral for valve replacement. However, the surgical management of subpulmonary atrioventricular valve (morphologic mitral valve [MV]) regurgitation and outcomes has not been well studied.

METHODS

Of 108 ccTGA patients undergoing atrioventricular valve surgery from 1979 to 2022, 22 patients (20%) underwent MV surgery. Demographics, etiology of valve regurgitation, operative details, and outcomes of these 22 patients were retrospectively reviewed. Follow-up at 1, 5, and 10 years was available for 18 (82%), 13 (59%), and 11 patients (50%), respectively.

RESULTS

Median age was 37 years (interquartile range, 29-57 years). Intrinsic MV pathology was present in 18 individuals (82%). Operations included repair in 16 patients (73%), replacement in 6 (27%), and concomitant replacement of TV in 16 (73%). There was 1 perioperative death (5%) in a patient undergoing an emergent operation for severe acute-on-chronic heart failure due to worsening TV regurgitation. During a median follow-up of 12 years (interquartile range, 2-19 years), 7 patients (32%) died. Among the 16 patients who underwent repair, recurrent moderate or greater regurgitation was seen in 15%, 29%, and 43% of repairs in patients with annular, leaflet, and lead-induced regurgitation, respectively.

CONCLUSIONS

Concomitant TV and MV disease occur much less frequently than isolated TV disease in ccTGA. Intrinsic MV disease is most commonly observed but appears less amenable to successful repair compared with mitral repair in the systemic position and suggests MV replacement may be preferred in ccTGA patients.

Respect Versus Resect Approaches for Mitral Valve Repair: A Meta-Analysis of Reconstructed Time-to-Event Data

Mitral valve repair (MVr) has been associated with superior long-term survival and freedom from valve-related complications compared with mitral valve replacement for primary mitral regurgitation (MR). The 2 main approaches for MVr are chordal replacement ("respect approach") and leaflet resection ("resect approach"). We performed a systematic review and a meta-analysis using 3 search databases to compare the long-term end points between both approaches. The primary end point was long-term survival. The secondary end points were long-term MR recurrence and reoperation. After reconstruction of time-to-event data for the individual survival analysis, pooled Kaplan-Meier curves for the end points were generated. A total of 14 studies (5,565 patients) were included in the analysis. The respect approach was associated with superior survival compared with the resect approach in the overall sample (hazard ratio [HR] 0.73, 95% confidence interval [CI] 0.56 to 0.96, p = 0.024, n = 3,901 patients) but not in the risk-adjusted sample (HR 1.00, 95% CI 0.55 to 1.82, p = 0.991, n = 620 patients). There was no difference between the approaches in the rate of MR recurrence in the overall sample (HR 1.39, 95% CI 0.92 to 2.08, p = 0.116, n = 1,882 patients) or in the risk-adjusted sample (HR 1.62, 95% CI 0.76 to 3.47, p = 0.211, n = 288 patients). The data for reoperation were only available in the overall sample and did not reveal a difference (HR 0.92, 95% CI 0.62 to 1.35, p = 0.663, n = 3,505 patients). In conclusion, the current evidence suggests no difference in long-term mortality, MR recurrence, or reoperation between the resect and respect approaches for MVr after adjusting for patient risk factors. More long-term follow-up data are warranted.

Mitral valve repair for degenerative mitral regurgitation with Carpentier's functional classification type II in elderly patients: a single center experience

OBJECTIVE

Mitral valve (MV) repair for Carpentier functional classification Type II (C-II) mitral regurgitation (MR) is widely accepted because of its efficacy. It is unclear whether MV repair has the same benefits in elderly patients as in younger patients because of their lower life expectancy. Herein, we examined the midterm results of MV repair for C-II mitral regurgitation, especially in patients aged ≧70 years.

METHOD

A retrospective review was performed on 176 patients who underwent MV repair for C-II mitral regurgitation with a median age of 65 years; 55 (31%) patients were ≧70 years, and 124 were male (71%). Lesions of the mitral valve were isolated from the anterior leaflet (48 patients), posterior leaflet (113 patients), and both leaflets (15 patients), and included seven patients with Barlow's disease. We compared the outcomes between patients aged ≧70 years (≧70 years; median age, 76 years) and those aged < 70 years (median age, 60 years).

RESULTS

In terms of the durability of MV repair in elderly patients, there were no significant differences in the rates of freedom from reoperation or MR recurrence at 5 years between patients aged < 70 years and those aged ≧70 years (reoperation:98% in < 70 years versus 89% in ≧70 years; P = 0.4053; MR recurrence:95% in < 70 years versus 81% in ≧70 years; P = 0.095). The mitral valve complexity was divided into two grades: Simple (isolated posterior mitral lesion) and Complex (isolated anterior lesion or both lesions). In patients aged < 70 years, there was no significant difference in the rate of freedom from MR recurrence at 5 years between the Simple and Complex groups (96% vs. 91%; P = 0.1029). In contrast, in patients aged ≧70 years, the MR recurrence rate at 3 years in Complex was significantly higher in the Complex group than in the Simple (100% vs. 80%; P = 0.0265).

CONCLUSIONS

We studied the outcomes of MV repair for C-II in MR. In elderly patients, MR recurrence was higher in complex lesions than in simple lesions. MV replacement may be considered for elderly patients with complex mitral valve lesions, if appropriately selected.

Surgical strategy and outcomes for atrial functional mitral regurgitation: All functional mitral regurgitation is not the same!

OBJECTIVE

Functional mitral regurgitation (FMR) is a cardiac pathology that causes the mitral valve to malfunction, leading to mitral regurgitation (MR). The optimal strategy for FMR remains unclear, and FMR outcomes are poor. All etiologies of FMR might not be the same, and subdividing patients with FMR caused by atrial (AFMR) versus ventricular FMR pathology might be important. Herein, we present outcomes of patients with AFMR to define this "new" population.

METHODS

Data of patients who underwent mitral valve repair for MR from 2000 to 2020 were reviewed. Patients with degenerative/myxomatous disease, ejection fraction <50% (ventricular FMR), and miscellaneous etiologies including endocarditis and rheumatic disease were excluded to isolate a population of "pure" AFMR patients. Descriptive characteristics and outcomes data were analyzed.

RESULTS

Among 123 total AFMR patients, mean preoperative left atrial dimensions were enlarged to 4.9 (95% CI, 4.7-5.0) cm, whereas mean preoperative left ventricular diastolic dimensions remained near normal at 5.0 (95% CI, 4.9-5.2) cm. Preoperative atrial fibrillation was noted in 61% (74/123). Echocardiogram was performed in 58% (71/123) of patients at a median of 569 (interquartile range, 75-1782) days after surgery. Of those, 72% (51/71) had trivial or no MR, 22% (16/71) mild, and only 6% (4/71) moderate or greater MR. Only 1.6% (2/123) required redo mitral valve reoperation. Estimated 5-year survival was 74%.

CONCLUSIONS

Patients with AFMR do well after mitral valve repair using an annuloplasty ring, with low rates of reoperation, mortality, and recurrence of MR. Mitral annuloplasty should be considered the surgical therapy of choice for AFMR.

Long-term outcome of isolated mitral valve repair versus replacement for degenerative mitral regurgitation in propensity-matched patients

Objective

This study was performed to investigate the long-term outcomes in patients with degenerative mitral regurgitation (MR) undergoing mitral valve repair (MVr) versus mitral valve replacement (MVR) without concomitant surgeries.

Methods

The study cohort comprised 1493 patients with degenerative MR who were treated with isolated mitral valve surgery between January 2000 and December 2017 in a large multicenter (5 hospitals) registry of the Province of British Columbia, Canada, including 991 with repair and 502 with replacement. A propensity-matched comparison and risk-adjusted model were used to analyze the outcomes.

Results

After propensity matching (415 matched pairs), the 30-day mortalities were 2.4% and 3.6% in the MVr and MVR groups respectively (odds ratio [OR], 1.500; 95% confidence interval [CI], 0.674-3.339; P = .32). The MVR group had significantly greater rates of prolonged inotrope usage >24 hours (P = .024), prolonged ventilation (P = .039), and blood transfusion (P = .023). The respective 1-, 5-, 10-, and 15-year survival rates were 95.7%, 88.8%, 71.4%, and 53.3% in the MVr group, and 93.0%, 81.6%, 61.3%, and 46.0% in the MVR group (hazard ratio [HR], 1.355; 95% CI, 1.105-1.661; P = .004). A multivariable analysis revealed that MVR was an independent risk factor for 30-day mortality (OR, 2.270; 95% CI, 1.089-4.732; P = .029) and long-term mortality (HR, 1.417; 95% CI, 1.161-1.729; P < .001). The HR of MVR over MVr remained consistently greater than 1.0 across all ages.

Conclusions

MVr is associated with lower postoperative morbidity and better long-term survival compared with MVR in patients undergoing isolated mitral valve surgery for degenerative MR. The benefit of MVr appears age-independent.

Mitral Valve Intervention in Elderly or High-Risk Patients: A Review of Current Surgical and Interventional Management

Mitral regurgitation is a prevalent valvular disease, and its management has gained increasing importance because of the aging population. Although traditional surgery remains the gold standard, the field of transcatheter therapies, including transcatheter edge-to-edge repair and, more recently transcatheter mitral valve replacement are advancing and are being explored as viable alternatives, particularly for patients at high surgical risk. It is essential to emphasize the necessity of a multidisciplinary team approach, involving specialized valve teams, imaging experts, cardiac anaesthesiologists, and other relevant specialists, is crucial in achieving optimal outcomes. Furthermore, proper execution of procedures, postprocedural care, and diligent follow-up for these patients are essential components for successful results. It is essential to underscore that traditional mitral valve surgery continues to play a significant role. Simultaneously, it is important to acknowledge the expanding array of transcatheter interventions available for this specific patient population.

Echocardiographic Evaluation of Successful Mitral Valve Repair or Need for a Second Pump Run in the Operating Room

Detailed preoperative and intraoperative echocardiographic assessment of the mitral valve apparatus is critical for a successful repair. The recent advent of 3-dimensional transesophageal echocardiography has added an extra pivotal role to transesophageal echocardiography in the assessment of mitral apparatus and mitral regurgitation. Because surgeons must rapidly decide whether cardiopulmonary bypass should be continued to be weaned off or a second pump run should be selected, the echocardiographer conducting intraoperative transesophageal echocardiography is required to be trained according to a certain algorithm. This review summarizes the current clinical role of intraoperative transesophageal echocardiography in mitral valve repair in the operating room.

1-Year Outcomes Following Transfemoral Transseptal Transcatheter Mitral Valve Replacement: The HighLife TSMVR Feasibility Study

BACKGROUND

A significant number of patients with severe mitral regurgitation (MR) are not suitable for either surgical or transcatheter edge-to-edge repair because of high surgical risk or inappropriate mitral valve anatomy.

OBJECTIVES

The aim of this study was to evaluate the HighLife Trans-Septal Mitral Valve Replacement (TSMVR) system in patients with symptomatic MR and high surgical risk.

METHODS

This prospective, multicenter, nonrandomized feasibility study evaluated the safety and performance of the HighLife TSMVR system in patients with moderate to severe or severe symptomatic MR during 1-year follow-up. Echocardiographic data were assessed at an independent core laboratory.

RESULTS

A total of 30 patients (mean age 75.6 years, 27% women, median Society of Thoracic Surgeons score 5.5%) with severe MR (90% with secondary MR, median left ventricular ejection fraction 43%) were treated at 13 sites. In 27 of the 30 patients, the HighLife TSMVR system was implanted successfully (technical success rate 90%). Device success at 30 days was 83%. After 1 year, 5 patients (17%) had died. None of the patients who underwent implantation required mitral valve reintervention. All patients who underwent implantation had no or trace (78%) or mild (22%) MR, the mean gradient of the HighLife valve was 5.1 mm Hg, and there were no signs of left ventricular outflow tract obstruction (mean gradient 2.0 mm Hg).

CONCLUSIONS

The 1-year results from the HighLife TSMVR feasibility study demonstrate a high technical success rate, excellent valve function, no left ventricular outflow tract obstruction, and no need for mitral valve reintervention. Additional patient outcomes and longer follow-up are needed to confirm these findings. (Expanded Study of the HighLife 28mm Trans-Septal Trans-Catheter Mitral Valve in Patients With Moderate-Severe or Severe Mitral Regurgitation and at High Surgical Risk; NCT04029363).

The Predictors and Outcomes of Functional Mitral Stenosis following Surgical Mitral Valve Repair: A Retrospective Analysis

To optimize mitral valve repair outcomes, it is crucial to comprehend the predictors of functional mitral valve stenosis (FMS), to enhance preoperative assessments, and to adapt intraoperative treatment strategies. This study aimed to identify FMS risk factors, contributing valuable insights for refining surgical techniques. Among 228 selected patients, 215 underwent postoperative echocardiography follow-ups, and 36 met the FMS criteria based on a mean trans-mitral pressure gradient of >5 mmHg. Patients with FMS exhibited higher pulmonary systolic arterial pressure and increased late mortality during the follow-up. Univariable logistic regression analysis identified several risk factors for FMS, including end-stage renal disease, anterior leaflet lesion, concomitant aortic valve replacement, smaller ring size, ring type, and neochordae implantation. Conversely, resection alone and resection combined with neochordae implantation had protective effects against FMS. Multivariable logistic regression analysis revealed that smaller ring sizes and patch repair independently predicted FMS. When focusing on degenerative mitral regurgitation, the neochordae implantation without resection in leaflet repair, emerged as an independent predictor of FMS. Surgeons should weigh the substantial impact of surgical procedures on postoperative trans-mitral pressure gradients, emphasizing preoperative evaluation and techniques such as precise ring size assessment and effective leaflet management.

Machine-learning-based prediction of survival and mitral regurgitation recurrence in patients undergoing mitral valve repair

OBJECTIVES

This study was conducted to assess long-term clinical outcomes after mitral valve repair using machine-learning techniques.

METHODS

We retrospectively evaluated 436 consecutive patients (mean age: 54.7 ± 15.4; 235 males) who underwent mitral valve repair between January 2000 and December 2017. Actuarial survival and freedom from significant (≥ moderate) mitral regurgitation (MR) were clinical end points. To evaluate the independent risk factors, random survival forest (RSF), extreme gradient boost (XGBoost), support vector machine, Cox proportional hazards model and general linear models with elastic net regularization were used. Concordance indices (C-indices) of each model were estimated.

RESULTS

The operative mortality was 0.9% (N = 4). Reoperation was required in 15 patients (3.5%). In terms of C-index, the overall performance of the XGBoost (C-index 0.806) and RSF models (C-index 0.814) was better than that of the Cox model (C-index 0.733) in overall survival. For the recurrent MR, the C-index for XGBoost was 0.718, which was the highest among the 5 models. Compared to the Cox model (C-index 0.545), the C-indices of the XGBoost (C-index 0.718) and RSF models (C-index 0.692) were higher.

CONCLUSIONS

Machine-learning techniques can be a useful tool for both prediction and interpretation in the survival and recurrent MR. From the machine-learning techniques examined here, the long-term clinical outcomes of mitral valve repair were excellent. The complexity of MV increased the risk of late mitral valve-related reoperation.

Transcatheter Mitral Valve Replacement Using Transcatheter Aortic Valve or Dedicated Devices: Current Evidence and Future Prospects

Transcatheter mitral valve replacement (TMVR) is a novel and evolving field dedicated to addressing the therapeutic challenges posed by patients at high surgical risk with mitral valve disease. TMVR can be categorized into two distinct fields based on the type of device and its specific indications: TMVR with transcatheter aortic valves (TAV) and TMVR with dedicated devices. Similar to aortic stenosis, TMVR with TAV requires a rigid support structure to secure the valve in place. As a result, it is indicated for patients with failing bioprothesis or surgical rings or mitral valve disease associated with severe mitral annular calcification (MAC), which furnishes the necessary foundation for valve anchoring. While TMVR with TAV has shown promising outcomes in valve-in-valve procedures, its effectiveness remains more contentious in valve-in-ring or valve-in-MAC procedures. Conversely, TMVR with dedicated devices seeks to address native mitral regurgitation, whether accompanied by MAC or not, providing an alternative to Transcatheter Edge-to-Edge Repair (TEER) when TEER is not feasible or expected to yield unsatisfactory results. This emerging field is gradually surmounting technical challenges, including anchoring a valve in a non-calcified annulus and transitioning from the transapical route to the transeptal approach. Numerous devices are presently undergoing clinical trials. This review aims to furnish an overview of the supporting evidence for TMVR using TAV in each specific indication (valve-in-valve, valve-in-ring, valve-in-MAC). Subsequently, we will discuss the anticipated benefits of TMVR with dedicated devices over TEER, summarize the characteristics and clinical results of TMVR systems currently under investigation, and outline future prospects in this field.

Mitral Repair vs Replacement for Degenerative Mitral Regurgitation in Patients Aged ≥65 Years

BACKGROUND

The benefits of mitral valve repair vs replacement are well documented. However, survival benefits in the elderly population are more controversial. In this novel lifetime analysis, we hypothesize that survival benefits for valve repair vs replacement in the elderly are sustained throughout the patient's lifetime.

METHODS

From January 1985 through December 2005, 663 patients, aged ≥65 years with myxomatous degenerative mitral valve disease underwent primary isolated mitral valve repair (n = 434) or replacement (n = 229). Propensity score matching was used to balance variables potentially related to outcome.

RESULTS

Follow-up was complete in 99.1% of mitral repair and 99.6% of mitral replacement patients. In matched patients, perioperative mortality was 3.9% (9 of 229) for repair and 10.9% (25 of 229) for replacement (P = .004). Survival estimates (95% confidence limits) from 29-year follow-up for matched patients were 54.6% (48.0%, 61.1%) and 11.0% (6.8%, 15.2%) at 10 years and 20 years for repair patients, and 34.2% (27.7%, 40.7%) and 3.7% (1%, 6.4%) for replacement patients, respectively. Median survival (95% confidence limits) was 11.3 years (9.6, 12.2 years) for repair patients compared with 6.9 years (6.3, 8.0 years) for replacement patients (P < .001).

CONCLUSIONS

This study demonstrates that although the elderly population is prone to multiple comorbidities, survival benefits of isolated mitral valve repair vs replacement are sustained throughout the patient's lifetime.

Chordal force profile after neochordal repair of anterior mitral valve prolapse: An ex vivo study

Objective

This study aimed to biomechanically evaluate the force profiles on the anterior primary and secondary chordae after neochord repair for anterior valve prolapse with varied degrees of residual mitral regurgitation using an ex vivo heart simulator.

Methods

The experiment used 8 healthy porcine mitral valves. Chordal forces were measured using fiber Bragg grating sensors on primary and secondary chordae from A2 segments. The anterior valve prolapse model was generated by excising 2 primary chordae at the A2 segment. Neochord repair was performed with 2 pairs of neochords. Varying neochord lengths simulated postrepair residual mitral regurgitation with regurgitant fraction at >30% (moderate), 10% to 30% (mild), and <10% (perfect repair).

Results

Regurgitant fractions of baseline, moderate, mild, and perfect repair were 4.7% ± 0.8%, 35.8% ± 2.1%, 19.8% ± 2.0%, and 6.0% ± 0.7%, respectively (P < .001). Moderate had a greater peak force of the anterior primary chordae (0.43 ± 0.06 N) than those of baseline (0.19 ± 0.04 N; P = .011), mild (0.23 ± 0.05 N; P = .041), and perfect repair (0.21 ± 0.03 N; P = .006). In addition, moderate had a greater peak force of the anterior secondary chordae (1.67 ± 0.17 N) than those of baseline (0.64 ± 0.13 N; P = .003), mild (0.84 ± 0.24 N; P = .019), and perfect repair (0.68 ± 0.14 N; P = .001). No significant differences in peak and average forces on both primary and secondary anterior chordae were observed between the baseline and perfect repair as well as the mild and perfect repair.

Conclusions

Moderate residual mitral regurgitation after neochord repair was associated with increased anterior primary and secondary chordae forces in our ex vivo anterior valve prolapse model. This difference in chordal force profile may influence long-term repair durability, providing biomechanical evidence in support of obtaining minimal regurgitation when repairing mitral anterior valve prolapse.

Cardiac reverse remodeling in primary mitral regurgitation: mitral valve replacement vs. mitral valve repair

BACKGROUND

When feasible, guidelines recommend mitral valve repair (MVr) over mitral valve replacement (MVR) to treat primary mitral regurgitation (MR), based upon historic outcome studies and transthoracic echocardiography (TTE) reverse remodeling studies. Cardiovascular magnetic resonance (CMR) offers reference standard biventricular assessment with superior MR quantification compared to TTE. Using serial CMR in primary MR patients, we aimed to investigate cardiac reverse remodeling and residual MR post-MVr vs MVR with chordal preservation.

METHODS

83 patients with ≥ moderate-severe MR on TTE were prospectively recruited. 6-min walk tests (6MWT) and CMR imaging including cine imaging, aortic/pulmonary through-plane phase contrast imaging, T1 maps and late-gadolinium-enhanced (LGE) imaging were performed at baseline and 6 months after mitral surgery or watchful waiting (control group).

RESULTS

72 patients completed follow-up (Controls = 20, MVr = 30 and MVR = 22). Surgical groups demonstrated comparable baseline cardiac indices and co-morbidities. At 6-months, MVr and MVR groups demonstrated comparable improvements in 6MWT distances (+ 57 ± 54 m vs + 64 ± 76 m respectively, p = 1), reduced indexed left ventricular end-diastolic volumes (LVEDVi; - 29 ± 21 ml/m2 vs - 37 ± 22 ml/m2 respectively, p = 0.584) and left atrial volumes (- 23 ± 30 ml/m2 and - 39 ± 26 ml/m2 respectively, p = 0.545). At 6-months, compared with controls, right ventricular ejection fraction was poorer post-MVr (47 ± 6.1% vs 53 ± 8.0% respectively, p = 0.01) compared to post-MVR (50 ± 5.7% vs 53 ± 8.0% respectively, p = 0.698). MVR resulted in lower residual MR-regurgitant fraction (RF) than MVr (12 ± 8.0% vs 21 ± 11% respectively, p = 0.022). Baseline and follow-up indices of diffuse and focal myocardial fibrosis (Native T1 relaxation times, extra-cellular volume and quantified LGE respectively) were comparable between groups. Stepwise multiple linear regression of indexed variables in the surgical groups demonstrated baseline indexed mitral regurgitant volume as the sole multivariate predictor of left ventricular (LV) end-diastolic reverse remodelling, baseline LVEDVi as the most significant independent multivariate predictor of follow-up LVEDVi, baseline indexed LV end-systolic volume as the sole multivariate predictor of follow-up LV ejection fraction and undergoing MVR (vs MVr) as the most significant (p < 0.001) baseline multivariate predictor of lower residual MR.

CONCLUSION

In primary MR, MVR with chordal preservation may offer comparable cardiac reverse remodeling and functional benefits at 6-months when compared to MVr. Larger, multicenter CMR studies are required, which if the findings are confirmed could impact future surgical practice.

Predictability and durability of mitral valve repair in patients with severe degenerative mitral regurgitation in medium sized centres

INTRODUCTION

Mitral valve repair (MVr) is now the treatment of choice to correct severe degenerative mitral regurgitation (MR). Repair rates vary greatly from centre to centre, and the concept of heart valve centres of excellence has been established.

OBJECTIVE

The purpose of this study was to see whether large international centre repair rates, and outcomes, are transferrable to medium-sized centres with an interest in mitral repair.

METHODS

Between 2011 and 2018, a total of 346 patients underwent mitral valve surgery by a single surgeon. Of these, 238 consecutive patients had repairs, or attempted repairs for degenerative MR, and are included in this study.

RESULTS

The study sample consisted of 71% male patients and had a mean age of 64.4 ± 12.3 years; 66% of the study population had concomitant procedures. The overall repair rate in this cohort is 99%. Mean follow up was 3.7 ± 1.9 years. At 5 years, the freedom from MR ≥ 3+ was 95.9 ± 1.9% and at 7 years 91.1 ± 3.8%. Freedom from reoperation at 5 years was 92.9 ± 3.7%, while the 5 years actuarial survival was 89.1 ± 3.7%. On a multivariate analysis, predischarge echo grade was associated with higher risk of future reoperation (odds ratio (OR) = 21.82, p = 0.05). Only age (OR = 1.3, p = 0.03) was predictive of long-term survival.

CONCLUSIONS

In specialised medium-sized heart centres, where the surgical team have undergone specialist mitral training, favourable short- and long-term outcomes are achievable with mitral repair rates similar to those from large international centres of excellence. In these heart centres, early surgery should be considered for all patients with severe degenerative MR.

Robotic mitral valve repair surgery: where do we go from here?

Surgical mitral valve repair through median sternotomy has long presented the treatment of choice for degenerative mitral valve disease. In recent decades, minimal invasive surgical techniques have been developed and are now gaining widespread popularity. Robotic cardiac surgery presents an emerging field, initially adopted only by selected centres, mostly in the United States. In recent years, the number of centers interested in robotic mitral valve surgery has grown with an increasing adoption in Europe as well. Increasing interest and surgical experience gained are stimulating further developments in the field and the full potential of robotic mitral valve surgery remains to be developed.

Microinvasive mitral valve surgery: Current status and status quo

Surgical mitral valve repair, performed either through median sternotomy or minimal invasive approach, presents the gold standard treatment for degenerative mitral valve disease. In dedicated centres, high repair and low complication rates have been established with excellent valve repair durability. Recently, new techniques have been introduced, that allow mitral valve repair to be performed through small surgical incisions and while avoiding cardio-pulmonary bypass. These new techniques, however, conceptually differ significantly when compared to surgical repair and it remains questionable whether they are capable of reproducing the results of surgical treatment.

Transcatheter mitral valve implantation: Implications of interventional technique and 3D echocardiography for complex valve-in-valve paravalvular leak

Transcatheter mitral valve replacement (TMVR) has emerged as a feasible alternative to surgical reoperation in failed bioprostheses and rings. Residual mitral regurgitation following TMVR can present as a valve-in-valve paravalvular leak (PVL) and is associated with increased morbidity and mortality. Current therapies for valve-in-valve PVL are limited. We present a case of a symptomatic patient with severe valve-in-valve PVL after TMVR for a previous surgical bioprosthesis leak, who then underwent a second TMVR as a valve-in-valve-in-valve implantation with a 29 mm Edwards® SAPIEN 3 valve via transseptal approach using three-dimensional (3D) echocardiography. This unique case highlights the complexity of this clinical entity and recognizes 3D transesophageal echocardiography as a valuable tool to guide valve-in-valve PVL closures.

Intraprocedural Residual Mitral Regurgitation and Survival After Transcatheter Edge-to-Edge Repair: Prospective German Multicenter Registry (MITRA-PRO)

BACKGROUND

Residual mitral regurgitation (MR) is thought to be an important predictor of long-term survival following transcatheter edge-to-edge repair (TEER). Intraprocedural MR assessment using transesophageal echocardiography could be limited by image quality, hemodynamics, and patient sedation. The MitraScore is a validated multimodal approach for intraprocedural MR assessment during TEER.

OBJECTIVES

This study aimed to assess the impact of residual MR using the MitraScore on 1-year mortality.

METHODS

Patients undergoing mitral TEER were eligible for inclusion in the prospective, multicenter MITRA-PRO registry (A Prospective Registry Study on 1-Year Mortality and the Prognostic Significance of MitraScore After MitraClip Implantation in Patients With Mitral Regurgitation). Patients with a MitraScore ≤3 were defined as patients with mild residual MR after mitral TEER, whereas a MitraScore ≥4 was considered as relevant residual MR. Mortality, rehospitalization, and major adverse events were assessed 1 year after TEER.

RESULTS

A MitraScore ≤3 was found in 1,059 patients (71.0%), whereas 432 patients revealed a MitraScore ≥4 (29.0%). One-year mortality was significantly lower in patients with nonrelevant residual MR (MitraScore ≤3 14.6% vs MitraScore≥4 22.1%). An almost linear relationship between intraprocedural MitraScore after TEER and mortality was observed. The combined clinical endpoint of mortality and rehospitalization within the 1-year follow-up was also significantly lower in the MitraScore ≤3 group (31.5%) than in the MitraScore ≥4 group (40.8%). A subgroup analysis confirmed the predictive value of the MitraScore in patients with primary, secondary, or mixed MR etiologies.

CONCLUSIONS

Residual MR assessed by intraprocedural MitraScore after TEER predicts 1-year mortality and rehospitalization. Therefore, the multimodal MitraScore improves MR assessment during mitral TEER and might improve patient survival.(A Prospective Registry Study on 1-Year Mortality and the Prognostic Significance of MitraScore After MitraClip Implantation in Patients With Mitral Regurgitation [MITRA-PRO]; DRKS00012288).

Percutaneous MitraClip Device or Surgical Mitral Valve Repair in Patients With Primary Mitral Regurgitation Who Are Candidates for Surgery: Design and Rationale of the REPAIR MR Trial

Background The current standard of care for the treatment of patients with primary mitral regurgitation (MR) is surgical mitral valve repair. Transcatheter edge-to-edge repair with the MitraClip device provides a less invasive treatment option for patients with both primary and secondary MR. Worldwide, >150 000 patients have been treated with the MitraClip device. However, in the United States, MitraClip is approved for use only in primary patients with MR who are at high or prohibitive risk for mitral valve surgery. The REPAIR MR (Percutaneous MitraClip Device or Surgical Mitral Valve Repair in Patients With Primary Mitral Regurgitation Who Are Candidates for Surgery) trial is designed to compare early and late outcomes associated with transcatheter edge-to-edge repair with the MitraClip and surgical repair of primary MR in older or moderate surgical risk patients. Methods and Results The REPAIR MR trial is a prospective, randomized, parallel-controlled, open-label multicenter, noninferiority trial for the treatment of severe primary MR (verified by an independent echocardiographic core laboratory). Patients with severe MR and indications for surgery because of symptoms (New York Heart Association class II-IV), or without symptoms with left ventricular ejection fraction ≤60%, pulmonary artery systolic pressure >50 mm Hg, or left ventricular end-systolic diameter ≥40 mm are eligible for the trial provided they meet the moderate surgical risk criteria as follows: (1) ≥75 years of age, or (2) if <75 years of age, then the subject has a Society of Thoracic Surgeons Predicted Risk Of Mortality score of ≥2% for mitral repair (or Society of Thoracic Surgeons replacement score of ≥4%), or the presence of a comorbidity that may introduce a surgery-specific risk. The local surgeon must determine that the mitral valve can be surgically repaired. Additionally, an independent eligibility committee will confirm that the MR can be reduced to mild or less with both the MitraClip and surgical mitral valve repair with a high degree of certainty. A total of 500 eligible subjects will be randomized in a 1:1 ratio to receive the MitraClip device or to undergo surgical mitral valve repair (control group). There are 2 co-primary end points for the trial, both of which will be evaluated at 2 years. Each subject will be followed for 10 years after enrollment. The study has received approval from both the Food and Drug Administration and the Centers for Medicare and Medicaid Services, and enrolled its first subject in July 2020. Conclusions The REPAIR MR trial will determine the safety and effectiveness of transcatheter edge-to-edge repair with the MitraClip in patients with primary MR who are at moderate surgical risk and are candidates for surgical MV repair. The trial will generate contemporary comparative clinical evidence for the MitraClip device and surgical MV repair. Registration https://clinicaltrials.gov/ct2/show/NCT04198870; NCT04198870.

Prediction of Surgical Approach in Mitral Valve Disease by XGBoost Algorithm Based on Echocardiographic Features

In this study, we aimed to develop a prediction model to assist surgeons in choosing an appropriate surgical approach for mitral valve disease patients. We retrospectively analyzed a total of 143 patients who underwent surgery for mitral valve disease. The XGBoost algorithm was used to establish a predictive model to decide a surgical approach (mitral valve repair or replacement) based on the echocardiographic features of the mitral valve apparatus, such as leaflets, the annulus, and sub-valvular structures. The results showed that the accuracy of the predictive model was 81.09% in predicting the appropriate surgical approach based on the patient's preoperative echocardiography. The result of the predictive model was superior to the traditional complexity score (81.09% vs. 75%). Additionally, the predictive model showed that the three main factors affecting the choice of surgical approach were leaflet restriction, calcification of the leaflet, and perforation or cleft of the leaflet. We developed a novel predictive model using the XGBoost algorithm based on echocardiographic features to assist surgeons in choosing an appropriate surgical approach for patients with mitral valve disease.

Contemporary Anatomic Criteria and Clinical Outcomes With Transcatheter Mitral Repair

BACKGROUND

Consensus-driven criteria have recently been proposed for prediction of mitral transcatheter edge-to-edge repair outcomes, yet validation for response to therapy is needed. We examined the relation between contemporary criteria and outcomes with mitral transcatheter edge-to-edge repair therapy.

METHODS

Mitral transcatheter edge-to-edge repair patients were classified according to anatomic and clinical criteria (1) Heart Valve Collaboratory criteria for nonsuitability; (2) commercial indications (suitable); and (3) neither (ie, intermediate). Analyses for Mitral Valve Academic Research Consortium-defined outcomes of reduction in mitral regurgitation and survival were performed.

RESULTS

Among 386 patients (median age, 82 years; 48% women), the most common classification was intermediate (46%), with 138 patients (36%) and 70 patients (18%) in the suitable and nonsuitable categories, respectively. Nonsuitable classification was related to prior valve surgery, smaller mitral valve area, type IIIa morphology, larger coaptation depth, and shorter posterior leaflet. Nonsuitable classification was associated with less technical success (P<0.001) and survival free of mortality, heart failure hospitalization, and mitral surgery (P<0.001). Among the nonsuitable patients, technical failure or any 30-day major adverse cardiac event occurred in 25.7%. Nevertheless, in these patients, acceptable mitral regurgitation reduction without adverse events still occurred in 69%, and their 1-year survival with mild or no symptoms was 52%.

CONCLUSIONS

Contemporary classification criteria identify patients less suitable for mitral transcatheter edge-to-edge repair with respect to acute procedural success and survival, though patients most commonly fit an intermediate category. In experienced centers, sufficient mitral regurgitation reduction can be achieved safely in the selected patients even with challenging anatomy.

Mitral Repair With Complete Rings or Posterior Bands in Barlow Disease: Long-term Results

BACKGROUND

Complete rings or posterior bands are both commonly used during mitral valve repair, but which one ensures the best long-term outcome in patients with Barlow disease is a topic of debate. This study evaluated whether the type of annuloplasty device affects the long-term durability of the repair.

METHODS

We selected 296 consecutive patients with severe mitral regurgitation due to Barlow disease who underwent edge-to-edge mitral repair at our institution between 2004 and 2013. For the edge-to-edge repair, a complete semirigid ring was used in 151 patients, whereas a posterior flexible band was used in 145 patients. The clinical and echocardiographic outcomes of both groups were compared at long-term follow-up.

RESULTS

At 14 years, the overall survival was 87.3% ± 2.79% in the ring group and 94.1% ± 2.30% in the band group (P = .056). The incidence of mitral valve reintervention was 4.9% ± 1.95% in the ring group and 5.5% ± 2.53% in the band group (P = .371) at 14 years. The incidence of recurrence of mitral regurgitation ≥3+ and ≥2+ was 8.3% ± 2.64% in the ring group and 8.7% ± 3.07% in the band group (P = .991) and 26.5% ± 4.23% in the ring group and 17.4% ± 3.26% in the band group (P = .697), respectively. Mitral regurgitation ≥1+ at discharge was the only independent predictor of reoperation and recurrence of mitral regurgitation ≥3+ in the long-term.

CONCLUSIONS

In patients with Barlow disease undergoing edge-to-edge mitral valve repair, the type of annuloplasty device does not influence the long-term results. Achieving an optimal immediate result remains the key to maintain the stability of the repair at long-term.

3D echocardiography in mitral valve prolapse

Mitral valve prolapse (MVP) is the leading cause of mitral valve surgery. Echocardiography is the principal imaging modality used to diagnose MVP, assess the mitral valve morphology and mitral annulus dynamics, and quantify mitral regurgitation. Three-dimensional (3D) echocardiographic (3DE) imaging represents a consistent innovation in cardiovascular ultrasound in the last decades, and it has been implemented in routine clinical practice for the evaluation of mitral valve diseases. The focus of this review is the role and the advantages of 3DE in the comprehensive evaluation of MVP, intraoperative and intraprocedural monitoring.

Edge-to-Edge Technique Used as a Bailout for Suboptimal Mitral Repair: Long-term Results

BACKGROUND

For cases of initial suboptimal mitral valve repair, the edge-to-edge (EE) technique has been used as a bailout procedure. However the long-term durability of those rescued mitral valves is currently unknown. With this study we aim to evaluate the long-term clinical and echocardiographic results of the EE technique used to rescue patients with initial suboptimal conventional mitral valve repair.

METHODS

A retrospective review of our institutional database was done to query for patients who had undergone mitral valve repair with the EE technique used as a bailout procedure. The cumulative incidence function using death as a competing event was used to estimate cardiac death and redo for mitral valve replacement. To describe the time course of mitral regurgitation, we performed a longitudinal analysis using generalized estimating equations with random intercept for correlated data.

RESULTS

Eighty-one patients were selected. The median follow-up was 9.1 years (interquartile range, 6.7-12.1; maximum, 22.6 years). At 15 years the estimated Kaplan-Meier overall survival was 63.2% ± 8.69% (95% confidence interval, 43.76-77.46) and the predicted rate of moderate to severe mitral regurgitation recurrence was 16.67%. At 15 years the cumulative incidence function for redo for mitral valve replacement with death as a competing event was 2.5% (95% confidence interval, 0.48-7.84). No case of more than mild mitral stenosis was detected.

CONCLUSIONS

The EE technique can be effectively used as a bailout procedure in patients with suboptimal conventional mitral valve repair with satisfactory long-term results.

Functional analysis of differently expressed ferroptosis-related genes in patients with mitral valve prolapse

Background: The prevalence of mitral valve prolapse (MVP) in heart valvular diseases is globally increasing. However, the understanding of its etiology and pathogenesis is limited. So far, the relationship between ferroptosis-related genes and long non-coding RNAs (lncRNAs) in MVP remains unexplored. This study investigates the potential pathogenesis of ferroptosis-related genes in MVP and provides a therapeutic target for the disease.

Methods: Blood samples from patients with MVP and healthy volunteers were collected for transcriptomic sequencing to analyze the expression of ferroptosis-related differentially expressed genes (DEGs) and differentially expressed long non-coding RNAs (DElncRNAs Co-expression network of ferroptosis-related DEGs and DElncRNAs. Furthermore, this work conducted GO and KEGG enrichment analyses.

Results:CDKN2A, SLC1A4, ATF3, and other core genes related to the mitral valve prolapse were screened out. CDKN2A, SLC1A4, and ATF3 genes were at the core position of the network, regulated by numerous lncRNAs. Notably, these genes are primarily involved in the extracellular region and p53 signaling pathway.

Conclusion: In summary, CDKN2A, SLC1A4, and ATF3 regulate the pathophysiological process of MVP and are potential therapeutic targets.

Minimally invasive mitral valve surgery with or without robotics: Examining the evidence

Minimally invasive mitral valve surgery can be performed with or without robotic assistance. In this issue of the journal, Zheng et al. compare between these two approaches in a propensity‐matched study over a 5‐year period and show that the two techniques have similar successful short and mid‐term outcomes. Although we are proponents of the robotic approach, we agree with their conclusions and discuss in this commentary some of the previously published studies that have shown similar findings.

Outcomes After Transcatheter Edge-to-Edge Mitral Valve Repair According to Mitral Regurgitation Etiology and Cardiac Remodeling

BACKGROUND

Transcatheter edge-to-edge repair (TEER) has been increasingly used for selected patients with mitral regurgitation (MR), but limited data are available regarding clinical outcomes in patients with varied etiology and mechanism of MR.

OBJECTIVES

The aim of this study was to evaluate the outcomes of TEER according to etiology and left ventricular (LV) and left atrial remodeling.

METHODS

Consecutive patients who underwent TEER between 2007 and 2020 were included in the analysis. Among patients with functional MR (FMR), those with predominant LV remodeling were classified as having ventricular FMR (v-FMR), whereas those without LV remodeling but predominant left atrial remodeling were classified as having atrial FMR (a-FMR). The primary outcome was a composite of all-cause mortality and heart failure hospitalization at 2 years and was compared among patients with degenerative MR (DMR), a-FMR, and v-FMR.

RESULTS

A total of 1,044 patients (11% with a-FMR, 48% with v-FMR, and 41% with DMR) with a mean Society of Thoracic Surgeons score of 8.6 ± 7.8 underwent TEER. Patients with a-FMR had higher rates of atrial fibrillation and severe tricuspid regurgitation with larger left and right atria, whereas patients with v-FMR had lower LV ejection fractions with larger LV dimensions. Residual MR more than moderate at discharge was not significantly different among the 3 groups (5.2% vs 3.2% vs 2.6%; P = 0.37). Compared with patients with DMR, 2-year event rates of the primary outcome were significantly higher in patients with a-FMR and v-FMR (21.6% vs 31.5% vs 42.3%; log-rank P < 0.001).

CONCLUSIONS

Despite excellent procedural outcomes, patients with a-FMR and v-FMR had worse clinical outcomes compared with those with DMR.

Prognosis for Mitral Valve Repair Surgery in Functional Mitral Regurgitation

Purpose: Our aim was to evaluate the development of new significant mitral regurgitation and long-term survival after mitral repair surgery in functional mitral regurgitation.

Methods: A retrospective observational analysis of the recurrence of functional mitral regurgitation (ischemic and nonischemic) and global mortality during follow-up of 176 patients who underwent mitral repair surgery between 1999 and 2018 in our center was conducted.

Results: The etiology of functional mitral regurgitation was ischemic in 55.7% of cases. After surgery, mitral regurgitation was 0-I in 92.3% of cases. We conducted a long-term clinical follow-up of a mean 42.2 months and an echocardiographic follow-up of a mean 41.8 months. We observed mitral regurgitation of at least grade II in 52 patients (36.9%). Survival at 1, 3, and 5 years was 78.8%, 66.7%, and 52.3%, respectively. Predictive factors for global mortality were age (hazard ratio = 1.038, p = 0.01) and a depressed preoperative ejection fraction. After a competing risk analysis, we found the only predictive factor for the recurrence of mitral regurgitation in our series to be age (sub-hazard ratio = 1.03, 95% confidence interval = 1.01–1.06, p = 0.016).

Conclusion: Repair surgery for functional mitral regurgitation shows age as the only independent predictor of recurrence. Age and depressed ejection fraction were predictors of mortality.