Mitral valve repair versus replacement for patients with preserved left ventricular function without heart failure symptoms

Long-Term Outcomes of Mitral Valve Repair Versus Replacement in Patients with Ischemic Mitral Regurgitation: A Retrospective Propensity-Matched Analysis

BACKGROUND

The optimal surgical management of ischemic mitral regurgitation (IMR)-mitral valve repair (MVr) versus mitral valve replacement (MVR)-remains controversial, with limited evidence on long-term outcomes. This study aimed to compare the outcomes of MVr and MVR in patients with IMR, focusing on survival and recurrence of mitral regurgitation. Additionally, survival was compared based on preoperative characteristics.

METHODS

A retrospective cohort analysis was conducted at a tertiary referral center and included 759 patients who underwent surgery for IMR between 2009 and 2021. Propensity score matching identified 140 matched pairs. The outcomes assessed included hospital mortality, long-term survival, recurrence of mitral regurgitation, mitral valve reintervention rates, and echocardiographic changes over time.

RESULTS

In the matched cohort, no significant differences were observed in hospital mortality (10% for MVr vs. 10.7% for MVR, p > 0.99) or long-term survival (p = 0.534). However, MVr was associated with a higher rate of recurrent moderate or higher mitral regurgitation (29.04% vs. 10.37%, p < 0.001) compared to MVR. The mitral valve reintervention rates did not differ significantly between the groups. Echocardiographic follow-up revealed significant improvements in left ventricular function and dimensions, with no significant differences between the groups. A subgroup analysis revealed no difference in survival according to the age, gender, ejection fraction, EuroSCORE category, or right ventricular function between the MVr and MVR patients.

CONCLUSIONS

MVr and MVR for IMR yielded comparable survival rates, but MVr was associated with a higher risk of recurrent MR. The efficacy of both surgical approaches across diverse patient populations was comparable, reinforcing the need for individualized decision-making based on other clinical and anatomical considerations.

Mitral Valve Repair Versus Replacement in Patients Undergoing Concomitant Aortic Valve Replacement

AIM

Mitral valve repair (MVr) is associated with more favourable long-term outcomes than mitral valve replacement (MVR) in cases of isolated mitral valve disease suitable for repair. However, there is debate regarding whether the superiority of MVr extends to patients with concomitant aortic and mitral valve disease. Therefore, this meta-analysis was conducted to compare the survival benefits between aortic valve replacement (AVR) plus MVr with a double valve replacement (DVR).

METHOD

A comprehensive literature search was conducted on PubMed, EMBASE, and Cochrane until 20 October 2022. Studies comparing MVr and MVR in patients undergoing concomitant AVR were included. The primary outcome was long-term survival. The secondary outcomes were early mortality, mitral valve reoperation, and valve-related adverse events.

RESULTS

Sixteen studies with a total of 140,638 patients were included in this analysis. Patients undergoing AVR plus MVr exhibited a favourable trend in long-term survival (HR 0.85; 95% CI 0.71-1.03; p=0.10; I2=58%). The reconstructed Kaplan-Meier curve revealed that the long-term survival at 5, 10, and 15 years was higher in the AVR plus MVr (80.95%, 67.63%, and 51.18%, respectively) than in the DVR group (76.62%, 61.36%, 43.21%, respectively). Aortic valve replacement plus MVr had a lower risk of early mortality (RR 0.67; 95% CI 0.58-0.79; p<0.001; I2=77%), thromboembolic events (RR 0.81; 95% CI 0.67-0.98; p=0.03; I2=5%), and haemorrhagic events (RR 0.87; 95% CI 0.78-0.98; p=0.01; I2=59%). Moreover, both groups displayed comparable rates of mitral valve reoperation (HR 1.73; 95% CI 0.86-3.48; p=0.13; I2=60%) and infective endocarditis (RR 1.60; 95% CI 0.65-3.93; p=0.31; I2=0%). However, the rate of reoperation for AVR plus MVr significantly increased in rheumatic heart disease patients (HR 3.30, 95% CI 1.66-6.59; p<0.0001).

CONCLUSIONS

Compared with DVR, AVR plus MVr was associated with favourable long-term survival, reduced early mortality risk, and a lower incidence of thromboembolic and haemorrhagic events without increasing the risk of mitral valve reoperation or infective endocarditis in unselected patients. However, higher reoperation rates were observed in rheumatic heart disease patients undergoing AVR plus MVr.

Population-Based Analysis of Late Outcomes of Mitral Valve Repair for Degenerative Mitral Valve Regurgitation

Background

Population-based analyses may reduce uncertainty related to referral bias and/or incomplete follow-up.

Objectives

This study analyzed long-term mortality and durability of mitral valve repair in a geographically defined population with clinical and echocardiographic follow-up.

Methods

We used the Rochester Epidemiology Project to identify 153 Olmsted County patients who underwent mitral valve repair for degenerative regurgitation from 1993 to 2018. Survival was compared to a gender- and age-matched U.S. population using the Kaplan-Meier method. Cumulative incidence and repeat operation rates were estimated, accounting for the completing risk of death.

Results

The median age of the cohort was 61 years (IQR: 53-73 years), 112 patients (73%) were men, and the left ventricular ejection fraction was 65% (IQR: 60%-69%). Triangular resection of the P2 scallop combined with a 63 mm posterior band annuloplasty was performed in 108 (71%) patients. The median clinical follow-up was 13.8 years (IQR: 11.5-16.2 years), while echocardiography follow-up was available in 152 (99%) patients at 6.6 years (IQR: 1.3-12.8 years). The probability of developing severe mitral regurgitation was 4% (IQR: 3%-7%) in 9 years. Cumulative incidence of repeat mitral valve operation was 8% (n = 10) at 20 years. The probability of developing severe tricuspid regurgitation was 5% (IQR: 4%-8%) in 10 years, but no subsequent tricuspid valve operation was performed. Survival following mitral valve repair was superior to an age- and sex-matched control population (P < 0.001).

Conclusions

Mitral valve repair for degenerative disease is durable with exceedingly low repeat operation and mortality up to 20 years of follow-up. There was also a low rate of subsequent development of significant tricuspid valve regurgitation.

Mitral Valve Repair for Mitral Regurgitation in Patients With Marfan Syndrome

BACKGROUND

There is concern about the durability of mitral valve repair (MVr) for mitral regurgitation (MR) in Marfan patients due to limited long-term data. Furthermore, a detailed time course of changes in cardiac function after MVr in Marfan patients has not been reported. We examined repair techniques, postoperative cardiac function, and outcomes of MVr in Marfan patients.

METHODS AND RESULTS

We retrospectively reviewed 29 Marfan patients (mean [±SD] age 27.4±14.8 years) who underwent MVr at The University of Tokyo Hospital from 2010 to 2022. The mean follow-up period was 5.2±3.2 years. The causes of MR were isolated anterior leaflet prolapse in 25% of patients, isolated posterior leaflet prolapse in 11%, and bileaflet prolapse in 64%. Echocardiographic findings showed significant decreases in left ventricular (LV) diastolic and left atrial diameters 1 week after MVr. LV systolic diameter was significantly decreased 3 years after MVr, and LV ejection fraction initially declined before subsequently increasing. The in-hospital and 30-day mortality rates were 0%. At 5 years, the overall survival rate was 94% and the rate of freedom from MR was 84%.

CONCLUSIONS

The mid- to long-term outcomes after MVr in Marfan patients were satisfactory, supporting the durability of MVr in these patients. Postoperative cardiac reverse remodeling occurred in a phased manner in Marfan patients, similar to that in patients with degenerative MR.

Outcomes and Complications of Mitral and Tricuspid Transcatheter Edge-to-edge Repair

In the realm of innovative medical procedures, TEER (transcatheter edge-to-edge repair) has emerged as a promising field, showcasing significant growth and advancements. Mitral TEER has been performed for the last two decades; in contrast, tricuspid TEER is newer, with long-term outcomes pending. This article aims to provide a comprehensive review of the current literature, with a primary focus on outcomes and potential complications associated with both procedures. Both procedures carry a low risk of complications when done by experienced providers. A team approach involving specialists in cardiology, cardiothoracic surgery, cardiac imaging and heart failure ensures comprehensive care. A unified approach encompassing preprocedural workup, risk assessment, and standardised care throughout the procedure and recovery contributes to successful outcomes.

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.

Renal function improvement correlates with 3D echocardiographic findings: Effect of surgical mitral valve repair

BACKGROUND

The association between surgical treatment of mitral regurgitation (MR) and renal function is not sufficiently well-known. We tried to evaluate renal function before and after the procedure of surgical mitral valve repair (SMVR) in degenerative severe MR.

METHODS

Patients with primary severe (4+) MR and normal left ventricular ejection fraction (LVEF) that underwent SMVR, examined by a cutting-edge 3-dimensional (3D) echocardiographic probe were enrolled in this study. We took three CKD-EPI equations to measure estimated glomerular filtration rate (eGFR) before SMVR and shortly before patients discharge. A total of 40 patients with baseline lower mean eGFR were evaluated.

RESULTS

Measurements substantiated statistically significant improvements in eGFR (p < 0.001), multivariable linear regression modeling indicating prominent associations between increase in eGFR and decrease of MR (p = 0.003), decline of pulmonary arterial systolic pressure (p = 0.018), as well as increment of forward stroke volume (p = 0.02), in spite of LVEF reduction, left ventricular global longitudinal strain worsening and left atrial ejection fraction impairment.

CONCLUSIONS

Renal function improves after SMVR in patients with degenerative significant MR and preserved LVEF, regardless of cardiac functional worsening.

Mitral Valve Repair vs. Replacement by Different Etiologies - A Nationwide Population-Based Cohort Study

BACKGROUND

When mitral valve (MV) surgery is indicated, repair is preferred over replacement; however, this preference is not supported by evidence from clinical trials. Furthermore, the benefits of MV repair may not be universal for all etiologies of MV disease.

METHODS AND RESULTS

This study identified a total of 18,428 patients who underwent MV repair (n=4,817) or MV replacement (n=13,611) during 2001-2018 from Taiwan's National Health Insurance Research Database. These patients were classified into 4 etiologies: infective endocarditis (IE, n=2,678), rheumatic heart disease (RHD, n=4,524), ischemic mitral regurgitation (IMR, n=3,893), and degenerative mitral regurgitation (DMR, n=7,333). After propensity matching, all-cause mortality during follow-up was lower among patients receiving MV repair than among patients receiving MV replacement in the IE, IMR, and DMR groups (hazard ratio [HR]=0.72, 95% confidence interval [CI]: 0.55-0.93; HR=0.82, 95% CI: 0.73-0.92; and HR 0.73, 95% CI: 0.64-0.84, respectively). However, in the RHD group, the MV reoperation rate was higher after MV repair than after MV replacement (subdistribution HR=1.91, 95% CI: 1.02-3.55).

CONCLUSIONS

In comparison with MV replacement, MV repair was associated with a lower late mortality in patients with IE, IMR, and DMR, and a higher risk of reoperation in patients with RHD.

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

OBJECTIVE

Here we report our preclinical, proof-of-concept testing to assess the ability of a novel device to correct mitral regurgitation. The Milwaukee Heart device aims to enable any cardiac surgeon to perform high-quality mitral valve repair using a standard annuloplasty ring with a crosshatch of microporous, monofilament suture.

METHODS

Hemodynamic, echocardiographic, and videographic data were collected at baseline, following induction of mitral regurgitation, and after repair using porcine hearts in an ex vivo biosimulator model. A commercially available cardiac prosthesis assessment platform was then used to assess the hydrodynamic characteristics of the study device.

RESULTS

Porcine biosimulator pressure and flow metrics exhibited successful correction of mitral regurgitation following device implantation with similar values to baseline. Hydrodynamic results yielded pressure gradients and an effective orifice area comparable to currently approved prostheses.

CONCLUSIONS

The study device effectively reduced mitral valve regurgitation and improved hemodynamics in our preclinical model with similar biophysical metrics to currently approved devices. Future in vivo trials are needed to evaluate the efficacy, biocompatibility, and freedom from the most likely adverse events, such as device thrombosis, embolic events, and hemolysis.

Robotic repair for Barlow mitral regurgitation: Repairability, safety, and durability

OBJECTIVE

In Barlow disease, increased repair complexity drives decreased repair rates. We evaluated outcomes of a simplified approach to robotic mitral repair in Barlow disease.

METHODS

A prospective institutional registry with vital-statistics, statewide admissions and echocardiographic follow-up was used to identify 924 consecutive patients undergoing robotic surgery for degenerative mitral regurgitation (MR) between 2005 and 2020, including 12% (n = 111) with Barlow disease. Freedom from >moderate (>2+) MR was analyzed with death as a competing risk and predictors of failure were analyzed using multivariable Cox regression. Median follow-up was 5.5 years (range, 0-15 years).

RESULTS

Patients with Barlow disease were younger (median, age 59 years; interquartile range [IQR], 51-67 vs 62; IQR, 54-70 years, P = .05) than patients without Barlow disease. Replacements were performed in 0.9% (n = 1) of patients with Barlow disease and 0.8% (n = 6) of patients without Barlow disease (P = 1). Repairs comprised simple leaflet resection and annuloplasty band in 73.9% (n = 546) of non-Barlow valves versus 12.7% (n = 14) of patients with Barlow disease who required neochordae (53.6%, n = 59), chordal transfer (20%, n = 22), and commissural sutures (37.3%, n = 41), with longer cardiopulmonary bypass time (median 133; IQR, 117-149 minutes vs 119; IQR, 106-142 minutes, P < .01). Survival free from greater than moderate MR at 5 years was 92.0% (95% confidence interval [CI], 80.2%-98.1%) in patients with Barlow disease versus 96.0% (95% CI, 93.3%-98.0%) in patients without Barlow disease (P = .40). Predictors of late failure included Barlow disease (hazard ratio, 3.9; 95% CI, 1.7-9.0) and non-Barlow isolated anterior leaflet prolapse (hazard ratio, 5.6; 95% CI, 2.3-13.4).

CONCLUSIONS

Barlow disease may be reliably and safely repaired with acceptable long-term durability by experienced robotic mitral surgery programs.

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.

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.

Adoption of minimally invasive mitral valve surgery: single-centre implementation experience in Vietnam

The adoption of minimally invasive mitral valve surgery (MIMVS) has become a prominent trend in mitral valve procedures. This article emphasizes that the success of the MIMVS program relies not only on effective teamwork but also on comprehensive hospital support and a clearly defined training strategy. Additionally, targeted marketing initiatives that highlight the value of the heart valve centre are crucial for sustaining the program's success and attracting a consistent patient flow. The implementation of these strategies requires diligent execution, consistent maintenance, and continuous improvement to ensure the triumph of the MIMVS program. This article aims to share our experience in implementing MIMVS at our centre, providing valuable insights for centres that have yet to adopt this approach or have low adoption rates. While acknowledging that sharing our centre's experience cannot guarantee success in all centres, customizing the implementation by selecting appropriate features and access points is vital. Each centre may encounter unique challenges, and tailoring the strategy to address specific needs will enhance the effectiveness of the MIMVS program.

Short-Term Results on Leaflet Mobility in Patients Undergoing Rheumatic Mitral Valve Repair With an Efficient 4-Step Commissuroplasty Technique

BACKGROUND

Mitral valve stenosis (MS) is the primary pathologic feature of rheumatic mitral valve disease, and the complex repair affects its clinical outcome. This study aimed to examine the efficacy of the 4-step commisuroplasty "SCORe" procedure by assessing changes in the mobility of mitral valve leaflets and its clinical effects.

METHODS

From September 1, 2018, to January 13, 2019, patients with MS who underwent mitral valve repair with the SCORe procedure in the study center were analyzed in this prospective study. Mitral valve structure was assessed by transthoracic echocardiography pre- and postoperatively as well as during follow-up.

RESULTS

In total, 60 consecutive patients were examined. In 56 patients (93.3%), mitral valve orifice area (MVOA) was less than 1.5 cm2, and mean (SD) MVOA for the whole cohort was 1.20 (0.34) cm2. The mobility of the anterior leaflet was improved (P < .001) during the cardiac cycle postsurgery, but that of the posterior leaflet was not (P = .591). The mean (SD) coaptation length was increased significantly from 6.69 (1.32) mm to 7.92 (1.24) mm (P < .001) postoperatively. Mean (SD) MVOAs increased to 2.24 (0.38) cm2 postoperatively (P < .001). During the 1-year follow-up, there were no deaths or reoperations. Follow-up echocardiography revealed minor or mild regurgitation in 98.3% of patients.

CONCLUSION

These findings demonstrated that the SCORe procedure can effectively improve the mobility of mitral leaflets and enlarge the valve orifice area in patients with rheumatic MS in China, with minimal complications and promising results.

Non-robotic minimally invasive mitral valve repair: a 20-year single-centre experience

OBJECTIVES

Minimally invasive mitral valve repair (MVR) promises major advantages over median sternotomy regarding cosmetic results and faster recovery. However, the long-term functional outcome of minimally invasive MVR has been questioned by critics because the limited access may not exclusively promise high-quality repair. This study examines the long-term outcome regarding survival and reoperation rate.

METHODS

All patients undergoing minimally invasive MVR from February 2000 until March 2020 were included in this study. Baseline clinical and surgical characteristics were summarized from the internal database. Primary end points were survival and freedom from reoperation, analysed via Kaplan-Meier curves. Secondary end points were periprocedural complications after minimally invasive MVR and incidence for recurrent mitral regurgitation >II°.

RESULTS

A total of 1194 patients underwent minimally invasive MVR, in 17 cases mitral valve replacement was required. The mean age was 55.1 years [47.6; 62.7]. The successful minimally invasive repair rate was 97%. The 30-day mortality was 0.6%. Survival was 96.7% [standard deviation (SD): 5.8%], 91.6% (SD: 1.1%) and 80.0% (SD: 11.2%) at 5, 10 and 20 years. The incidence of reoperation was 4.4% (SD: 3.2%), 10.3% (SD: 7.4%) and 16.7% (SD : 7.4%) at 5, 10 and 20 years, respectively. Concomitant procedures such as tricuspid valve repair and modified Cryo-maze procedure were performed in 263 cases.

CONCLUSIONS

Minimally invasive MVR for degenerative mitral regurgitation is safe, shows excellent functional long-term results and is associated with low perioperative and late mortality.

A soft functional mitral valve model prepared by three-dimensional printing as an aid for an advanced mitral valve operation

OBJECTIVES

The goal of this study was to build a soft mitral valve (MV) model for surgical simulation to aid with an advanced MV operation.

METHODS

Soft three-dimensional models of the MV were constructed by the mould-modelling method using silicone. The properties of the material used were tested and compared with those of the valve tissue. Then, the accuracy of the three-dimensional model was assessed from the perspectives of the pathological and morphological parameters. Thereafter, surgical simulation of MV repair, closure of the perforation and transcatheter MV replacement were simulated using our model. Two experienced surgeons were invited to perform and evaluate the fidelity and softness of the model. Morphological changes in the MV and the potential compression of the device on surrounding cardiac tissue were also measured after simulation.

RESULTS

The soft MV model was successfully constructed by the mould-modelling method. The property of the material used was closer to that of valve tissue than to that of the rigid model. In addition, the pathological details and morphological measurements of the three-dimensional model were consistent with the surgical findings. The simulated surgical procedure was successful using our model. Morphological changes, including the ratio of the leaflet/annulus area and the coaptation depth, were closely correlated with the regurgitation left after MV repair, which might be an indicator of the surgical effects. The results of this study demonstrated the great advantages of our constructed soft model in exploring the interaction of the device with the surrounding tissue. These advantages were not obtained using the rigid model in a previous study.

CONCLUSIONS

The soft MV model was successfully constructed using the mould-modelling method, and its physical properties were similar to those of heart tissue. In addition, the constructed model exhibited great advantages in surgical simulation and clinical application compared with the anatomical model.

Association between individual surgeon volume and outcome in mitral valve surgery: a systematic review

Background

Surgeon volume has been identified as a possible factor that influences outcomes in mitral valve (MV) surgery. The aim of this study was to systematically review all published studies on the association between individual surgeon volume and outcome in MV surgery.

Methods

PubMed was searched last on 19 November 2020. The reporting of this systematic review was done in accordance with PRISMA guidelines. Manuscripts were eligible when these studied individual surgeon volumes and its association with repair rate, mortality or reoperation. The methodological quality of the studies was assessed with the Newcastle-Ottawa Scale (NOS). Absolute numbers and percentages of the outcome measures, odds ratios (ORs), P values and threshold values regarding surgeon volume were collected.

Results

A total of 7 retrospective cohort studies were included in the qualitative analysis with total of 158488 patients. Definitions of surgeon volumes were found to be heterogenic and therefore pooling of data was not possible. Surgeon volume was significantly associated with repair rate (OR =1.25–5.5) and mortality (OR =0.46–0.84 and OR =1.50–2.27 depending on the reference group). Regarding reoperation, results were not consistent and did not always show a significant lower reoperation rate when surgeon volume increased. A mean threshold of minimally 30 MV surgeries per year was found.

Discussion

Higher surgeon volume is significantly associated with improved outcomes of repair rate and mortality. MV should preferentially be performed by high-volume surgeons and centralization of MV surgery might be necessary.

Mitral valve repair for degenerative mitral regurgitation in patients with left ventricular systolic dysfunction: early and mid-term outcomes

BACKGROUND

This study aims to evaluate the early and mid-term outcomes of mitral valve repair for degenerative mitral regurgitation (MR) in patients with left ventricular systolic dysfunction.

METHODS

From January 2005 to December 2016, the profiles of patients with degenerative MR who underwent mitral valve repair at our institution were analyzed. Left ventricular systolic dysfunction was defined as an ejection fraction < 60% or left ventricular end-systolic dimension > 40 mm. Finally, 322 patients with left ventricular systolic dysfunction were included in this study. The prognosis of left ventricular function during follow-up was evaluated and preoperative factors associated with deteriorated left ventricular systolic function during follow-up were analyzed.

RESULTS

The in-hospital mortality rate was 1.6%. The rate of eight-year overall survival, freedom from reoperation for mitral valve and freedom from recurrent MR were 96.9, 91.2 and 73.4%, respectively. Intraoperative residual mild MR (hazard ratio 4.82) and an isolated anterior leaflet lesion (hazard ratio 2.48) were independent predictive factors for recurrent MR. During follow-up, 212 patients underwent echocardiography examinations at our institution. Among them, 132 patients had improved left ventricular systolic function, and 80 patients had deteriorated left ventricular systolic. Freedom from recurrent MR was found in 75.9% of the improved left ventricular systolic function group and 56.2% of the deteriorated left ventricular systolic function group (P = 0.047). An age > 50 years (odds ratio 2.40), ejection fraction≤52% (odds ratio 2.79) and left ventricular end-systolic dimension≥45 mm (odds ratio 2.31) were independent risk factors for deteriorated left ventricular systolic function during follow-up.

CONCLUSIONS

Mitral valve repair could be safely performed for degenerative MR in patients with left ventricular systolic dysfunction. Intraoperative residual mild MR and an isolated anterior leaflet lesion were independent predictive factors for recurrent MR. An age > 50 years, ejection fraction≤52% and left ventricular end-systolic dimension≥45 mm were independent risk factors for deteriorated left ventricular systolic function during follow-up.

Surgical treatment of mitral regurgitation

PURPOSE OF REVIEW

Mitral repair is the best treatment for degenerative mitral regurgitation. Many patients are referred too late for optimal outcomes. The US repair vs. replacement rate is only 60-80%, at a time when the inferiority of replacement has been established. Therefore, widely used traditional techniques of repair are being reappraised.

RECENT FINDINGS

Identification of risk factors predictive of poor early and late outcome have improved timing for surgical referral. Composite risk scores have been developed. Novel echocardiographic, cardiac MRI, and molecular level risk factors could improve timing. Analysis of factors contributing to low repair rates is also of critical importance. The role of institutional and surgeon volumes have been identified. More detailed data on the importance of dynamic function of the mitral valve have led to improved repair techniques such as intraoperative simulation of end diastole and early systole, use of expanded polytetrafluoroethylene neochords instead of leaflet resection, and dynamic instead of rigid annuloplasty.

SUMMARY

Our perception of mitral regurgitation has changed from a seemingly simple condition to one of considerable complexity at multiple levels. National guidelines should be studied and followed.

Comparison of Mitral Valve Replacement and Repair for Degenerative Mitral Regurgitation: a Meta-analysis and Implications for Transcatheter Mitral Procedures

PURPOSE OF REVIEW

Surgical mitral valve repair is considered superior to replacement to treat primary mitral regurgitation. However, the heterogeneity of cohorts and the lack of consideration of confounding in the published literature raise potential biases. The aim of this study was to pool all available matched data comparing outcomes of mitral valve repair and replacement in the setting of primary mitral regurgitation.

RECENT FINDINGS

We searched Medline, Embase and the Cochrane Library Central Register of Controlled Trials to identify propensity-matched studies or reports with multivariable adjustment comparing repair and replacement in patients with primary mitral regurgitation. The primary outcome was all-cause mortality. DerSimonian and Laird random effects were used to perform the meta-analysis. Eight observational studies were selected including 4599 patients (3064 mitral repairs and 1535 replacements). Mean age ranged from 62 to 69 years, and the mean follow-up duration ranged between 3 and 9 years. Replacement was associated with an increased risk of long-term all-cause mortality compared to repair (HR of 1.68, 95% confidence interval 1.35-2.09, p < 0.001, τ² = 0.03). Surgical era and atrial fibrillation impacted the risk of mortality but not mitral anatomy. Neither repair nor replacement impacted significantly on the risk of re-operation after mitral surgery (HR 1.18, 95% CI 0.85-1.63, p = 0.33, τ² < 0.01). Mitral valve replacement is possibly associated with higher long-term mortality than mitral valve repair in primary mitral regurgitation but often used as a bailout option in more complex anatomy. Despite this observation, both techniques have similar risk of re-operation.

Echocardiographic prediction of surgical reparability in degenerative mitral regurgitation due to leaflet prolapse: a review

Introduction: Despite current guidelines provide recommendations for the optimal management of degenerative mitral regurgitation (MR), this condition remains often undertreated with delay in surgical referral and dismal effect on outcomes. Areas covered: This review focuses on the role of echocardiography in guiding mitral valve (MV) surgical repair in degenerative MR due to leaflet prolapse. Expert opinion: A stepwise protocol-driven echocardiography shared by referring physician and surgeon may help to guide referral to surgical repair in degenerative MR. This protocol particularly is useful to identify the ideal patho-anatomy for a successful and durable repair especially when early surgery is proposed and to refer the patient to centers of excellence in case of complex anatomy. Nearly 100% repair rate can be achieved when the surgical technique is adapted to the lesions seen in each valve. Three-dimensional echocardiography predicts repair complexity may be useful and should therefore be implemented. However, the current literature is far from comprehensive deriving from small, single-center studies. Therefore, reproducibility and external validation, especially with newly developed quantitative automated software, are still needed.