Very long-term durability of the edge-to-edge repair for isolated anterior mitral leaflet prolapse: Up to 21 years of clinical and echocardiographic results

Mitral Valve Repair of the Anterior Leaflet: Are We There Yet?

Mitral regurgitation is one of the most prevalent valvulopathies with a disease burden that incurs significant healthcare costs globally. Surgical repair of the posterior mitral valve leaflet is a standard treatment, but approaches for repairing the anterior mitral valve leaflet are not widely established. Since anterior leaflet involvement is less common and more difficult to repair, fewer studies have investigated its natural history and treatment options. In this review, we discuss surgical techniques for repairing the anterior leaflet and their outcomes, including survival, reoperation, and recurrence of regurgitation. We show that most patients with mitral regurgitation from the anterior leaflet can be repaired with good outcomes if performed at centers with expertise. Additionally, equal consideration for early repair should be given to patients with mitral regurgitation from both anterior and posterior pathology. However, more studies to better evaluate the efficacy and safety of anterior mitral valve leaflet repair are needed.

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.

Comparison of meta-analytical estimates of outcomes after Alfieri or neochordal repair in isolated anterior mitral prolapse

OBJECTIVES

Repair of the isolated degenerative anterior mitral leaflet has been considered more challenging and associated with compromised durability compared with isolated posterior leaflet in major series. Implantation of neochordae or Alfieri edge-to-edge is the most employed repair technique for isolated anterior repair currently, but little data exist comparing their relative durability. We sought to investigate this issue with this meta-analysis.

METHODS

A literature search was performed (Ovid MEDLINE, Ovid Embase and The Cochrane Library). The primary outcome was the incidence rate (IR) of reoperation, the secondary outcomes were recurrent moderately severe/severe mitral regurgitation (MR), in-hospital/30-day reoperation and mortality and follow-up mortality. A random-effect model was used. Leave-one-out, subgroup analysis (Alfieri versus neochordae) and meta-regression were done.

RESULTS

Seventeen studies (including 1358 patients) were included. At a weighted mean follow-up of 5.56 ± 3.31 years, the IR for reoperation was 14.45 event per 1000 person-year and significantly lower in Alfieri than neochordae repair (9.40 vs 18.61, P = 0.04) on subgroup analysis. The IR of follow-up moderately severe/severe MR was 19.89 event per 1000 person-year and significantly lower in Alfieri than neochordae repair (10.68 and 28.63, P = 0.01). In a sensitivity analysis comparing homogenous studies, a significant difference in the recurrence of regurgitation in favour of the Alfieri approach remained. There were no differences in operative outcomes or survival. There were significant associations between increased incidence of late reoperation and New York Heart Association class III/IV and associated coronary artery bypass graft procedure for whole cohort.

CONCLUSIONS

Alfieri repair may be associated with a lower incidence of recurrent MR compared with neochordae-based repair in the setting of isolated degenerative anterior mitral pathology. This is the first such meta-analysis and further inquiry into this area is needed.

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.

Closure of Left Atrial Appendage Has no Effect on Thromboembolic Rates after Mitral Valve Repair in Patients in Sinus Rhythm

Closure of the left atrial appendage (LAA) reduces the rates of TIA/stroke in patients in atrial fibrillation (AF) but its role in patients in sinus rhythm who undergo mitral valve repair (MV) for leaflet prolapse remains unknown. This study examined the effects of closing the LAA in TIA/stroke after MV repair. Our database on patients who had MV repair for leaflet prolapse from 2000 through 2019 was reviewed. After excluding patients at higher risk of TIA/stroke, 1050 patients in sinus rhythm were entered into the study: 781 with open LAA and 269 with surgically closed LAA. Using a propensity score analysis to compensate from clinical differences, 267 pairs of patients with open and closed LAA were matched. Follow-up was truncated at 5 years because routine closure of the LAA was performed only during recent years. The cumulative incidence of TIA/stroke at 5 years in the entire cohort was 2.7% [95% CI 1.9, 4.0]; it was 2.9% [95% CI 1.9, 4.4] in patients with open LAA,and 1.8% [95% CI 0.7, 4.9] in patients with closed LAA (P = 0.53). In the matched cohorts, the cumulative incidences of TIA/stroke did not differ significantly (match-adjusted HR [95% CI] = 0.80 [0.21, 2.98], P = 0.74), and multivariable Cox proportional hazard regression analysis also confirmed no difference in the risk of TIA/stroke between the 2 groups (regression-adjusted HR [95% CI] = 0.58 [0.12, 2.9], P = 0.47). This study failed to show a reduction in the risk of TIA/stroke by closing the LAA in patients in sinus rhythm (Figure 6). Closure of the LAA during MV repair warrants a larger and more rigorous study.

Clinical and echocardiographic predictors of the anterior mitral leaflet repair failure

BACKGROUND

Anterior mitral leaflet prolapse repair is a highly effective procedure, but despite excellent operative results still has an inferior long-term durability when compared to posterior leaflet repair.

METHODS

We analysed mitral repair durability in 74 consecutive patients operated for anterior leaflet prolapse between 2010 and 2021. Their pre- and postoperative clinical, echocardiographic data and repair durability as well, were compared with 74 randomly assigned posterior leaflet prolapse patients who underwent valve repair during the same period.

RESULTS

While groups were of similar age, patients with anterior leaflet prolapse had an inferior preoperative status in terms of functional reserve, atrial fibrillation, operative risk, ejection fraction and had more dilated left heart chambers as well. 1, 5, and 10-year freedom from repair failure was 87.1 ± 4.6%, 79.8 ± 6.5% and 50.7 ± 12.5% in the anterior, and 98.5 ± 1.5% respectively in the posterior leaflet group. Atrial fibrilation (hazard ratio [HR] 5.365; 95%; confidence interval [CI] 1.093-26.324 p = .038) and left ventricle end-systolic diameter (HR 1.160 95%; CI 1.037-1.299 p = .010) independently predicted anterior leaflet repair failure. Receiver Operating Curve analysis established left ventricle end-systolic diameter ≤42 mm as a cut-off value associated with improved anterior leaflet repair durability. Accordingly, 10-year repair durability in a subset of patients, with preserved left ventricle end-systolic diameter (≤42 mm) was 86.4 ± 7.8%.

CONCLUSION

Better long-term repair durability in patients with anterior mitral leaflet prolapse and preserved sinus rhytm and left-ventricle diameters justifies early reconstructive approach.

Anterior versus posterior leaflet mitral valve repair: A propensity-matched analysis

OBJECTIVE

Mitral valve repair is superior to replacement for degenerative disease, but long-term outcomes of anterior versus posterior leaflet repair remain poorly defined. We propensity matched anterior and posterior repairs to compare long-term outcomes.

METHODS

Patients undergoing first-time degenerative mitral repair between 1992 and 2018 were identified. Primary outcome was overall survival. Secondary outcomes were postprocedural residual mitral regurgitation and reoperation. From 1025 patients, 1:1 propensity score matching was performed, yielding 309 anterior (isolated anterior = 85, bileaflet = 224) and 309 isolated posterior repairs.

RESULTS

Age was 58 ± 15 years, ejection fraction was 57% ± 10%, and matched groups were well balanced. Anterior repairs had longer bypass (122 ± 53 vs 109 ± 43 minutes, P = .001) and crossclamp (94 ± 44 vs 85 ± 62 minutes, P = .033) times. Mean residual mitral regurgitation grade was 0.44 (95% confidence interval, 0.24-0.65) for anterior repair and 0.30 (95% confidence interval, 0.13-0.47) for posterior repair (P = .31). Overall, 92% (569/618) of matched patients had no residual mitral regurgitation, with no differences in mitral regurgitation grade between groups (P = .77). Survival did not differ between anterior (10 years: 72% ± 7%; 15 years: 63% ± 7%) and posterior (10 years: 74% ± 7%; 15 years: 60% ± 8%) groups (log-rank P = .93). Linearized incidence of reoperation was 0.62% per patient-year, including 0.74% for anterior and 0.48% for posterior repairs. Cumulative incidence of reoperation at 15 years was 7.5% after anterior repair and 4.9% after posterior repair (Gray's test P = .26).

CONCLUSIONS

No long-term survival or reoperation difference was found between posterior and anterior repair. On the basis of these findings, surgeons at centers of excellence should aim for repair of both anterior and posterior leaflet pathology with the same decision-making threshold over valve replacement for degenerative mitral disease.

Complications Following MitraClip Implantation

Purpose of Review

To provide a detailed overview of complications associated with MitraClip therapy and its development over time with the aim to alert physicians for early recognition of complications and to offer treatment strategies for each complication, if possible.

Recent Findings

The MitraClip system (MC) is the leading transcatheter technique to treat mitral regurgitation (MR) and has been established as a safe procedure with very low adverse event rates compared to mitral surgery at intermediate to high risk or in secondary MR. Lately, the fourth MC generation has been launched with novel technical features to facilitate device handling, decrease complication rates, and allow the treatment of even complex lesions.

Summary

Although the complication rate is low, adverse events are associated with increased morbidity and mortality. The most common complications are bleeding, acute kidney failure, procedure-induced mitral stenosis, and an iatrogenic atrial septal defect with unknown clinical impact.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11886-021-01553-9.

Resurgence of the edge-to-edge repair of the mitral valve

PURPOSE OF REVIEW

To provide a critical review of the application and outcomes of surgical edge-to-edge (E2E) or Alfieri repair for mitral valvulopathy.

RECENT FINDINGS

The E2E repair is a surgical technique to address mitral regurgitation, particularly suited when the responsible mechanism is bileaflet prolapse combined with enlarged annular area. It can also be used for a range of mitral valve pathologies. Surgically, the technique has been employed as a bailout for unsuccessful repair including residual mitral regurgitation because of systolic anterior motion (SAM). E2E repair should be accompanied by a ring annuloplasty for long-term repair durability. The simplicity of this approach makes it an ideal strategy during minimally-invasive mitral valve repair. It may also be performed via a transaortic approach at the time of aortic valve surgery to address less-than-severe mitral regurgitation or to address residual SAM following myectomy for hypertrophic obstructive cardiomyopathy. We review the surgical indication, potential complications including risk of mitral stenosis and the long-term outcomes of E2E repair.

SUMMARY

The E2E surgical repair is a simple and effective surgical strategy to address a wide range of mitral regurgitation. This is an important technique in the surgical armamentarium especially in cases of minimally-invasive mitral valve surgery.

Mitral and tricuspid annuloplasty ring dehiscence: a systematic review with pooled analysis

 

OBJECTIVES

Mitral and tricuspid ring annuloplasty dehiscence with consequent recurrent valve regurgitation is a rare but challenging procedural failure. The incidence and predisposing risk factors for annuloplasty ring dehiscence include technical and pathological ones.

METHODS

A systematic database search with pooled analysis was conducted of original articles that only included dehiscence rate of mitral and tricuspid ring in EMBASE, MEDLINE, Cochrane database and Google Scholar, from inception to November 2020. The outcomes included were dehiscence rate in mitral and tricuspid, type of ring implanted, dehiscence rate by pathology and by ring size and shape.

RESULTS

Our search yielded 821 relevant studies. Thirty-three studies met the inclusion criteria with a total of 10 340 patients (6543 mitral, 1414 tricuspid) of which 87 (mitral) and 30 (tricuspid) had dehiscence. Overall, dehiscence rate was 1.43%, diagnosed at a median of 4.5 ± 1.0 months postoperatively. A significant difference in mitral dehiscence rate was found by ring type (semi-rigid 1.86%, rigid 2.32%; flexible 0.43%; P < 0.001). There was no significant difference in rate of dehiscence by ring size (P = 0.067) and shape in mitral (P = 0.281) but there was higher dehiscence rate in ischaemic compared to non-ischaemic mitral regurgitation (3.91% vs 1.63%; P = 0.022). Among tricuspid studies, 9 of 10 studies did not report any dehiscence.

CONCLUSIONS

Although rigid, semi-rigid and flexible annuloplasty rings provide acceptable valve repair outcomes, mitral annuloplasty ring dehiscence is clinically more common among rigid rings. Understanding the multifactorial nature of ring dehiscence will help in identifying the patients at high risk and improve their clinical outcomes.

Advances in Mitral Valve Repair for Degenerative Mitral Regurgitation: Philosophy, Technical Details, and Long-Term Results

Degenerative mitral valve disease represents the most common cause of mitral regurgitation in industrialized countries. When left untreated, patients with severe degenerative mitral regurgitation show a poor clinical outcome. Conversely, a timely and appropriate correction provides a restored life expectancy and a good quality of life. Therefore, in this scenario, surgical mitral valve repair represents the gold standard of treatment. This review aims to analyze the indications, timing, and contemporary surgical techniques of mitral valve repair for degenerative mitral regurgitation. Moreover, the value of heart team approach and centers of excellence for mitral valve repair are also deeply discussed.

Excellent long-term results with minimally invasive edge-to-edge repair in myxomatous degenerative mitral valve regurgitation

OBJECTIVES

Previous series of minimally invasive mitral valve repairs showed excellent results at up to 10 years of follow-up. The goal of this study was to assess the long-term durability beyond 10 years of the edge-to-edge repair for myxomatous degeneration performed through a minimally invasive approach.

METHODS

Ninety-seven consecutive patients (mean age 35 ± 9 years; left ventricular ejection fraction 63 ± 6%) with severe myxomatous mitral regurgitation (MR) underwent mitral valve repair through a right minithoracotomy between 1999 and 2006. MR was due to lesions involving the posterior leaflet (7.2% of patients), anterior leaflet (12.4%) and both leaflets (80.4%).

RESULTS

No hospital deaths occurred. At hospital discharge all patients had no or trivial MR. Follow-up was 100% complete (median 15.5 years; interquartile range 13.6-17.0, max 19.3 years). The 16-year overall survival rate was 95.9 ± 2.02% [95% confidence interval (CI) 89.39-98.43]. At 16 years, the cumulative incidence function of cardiac death, with non-cardiac death as a competing risk, was 3.1 ± 1.75 (95% CI 0.83-8.02). Only 3 patients (4.1%) had redo operations for recurrent severe MR. At 16 years, the cumulative incidence functions of reoperation for and recurrence of MR ≥3+, with death as a competing risk, were 3.1 ± 1.76% (95% CI 0.83-8.02) and 5.6 ± 2.47% (95% CI 2.06-11.83), respectively. No predictors of recurrence of MR ≥3+ were identified. At the last follow-up, moderate MR (2+/4+) was detected in 17 patients (17.5%); most of the patients were in New York Heart Association functional class I-II (97%) and in sinus rhythm (90%).

CONCLUSIONS

Minimally invasive mitral valve edge-to-edge repair through a right minithoracotomy for myxomatous degeneration appears to be an effective and durable approach even in the long-term follow-up (up to 19 years).

[Infective prosthetic endocarditis following percutaneous edge-to-edge mitral valve repair - A Case-report of a successfully medically-treated Staphylococcus epidermidis endocarditis and a literature review]

During the last decade there has been a craze for the percutaneous edge-to-edge mitral valve repair technique with the Mitra-Clip device. This is an alternative treatment to mitral valve surgery for severe mitral regurgitation. In France, this device is aimed at poor candidates for mitral valve surgery. It involves intra-cardiac prosthetic material, which exposes them to the risk of bacterial endocarditis. The consequences of this infective disease can be dramatic, especially for these old patients who suffer from multiple comorbidities. It appears to be a rare but relatively unknown and potentially underestimated complication. The relative data remain scarce and consist of rare case-reports. We report an original case of a Methicilline-sensitive Staphylococcus epidermidis mitral endocarditis following the implantation of clips two months earlier. The patient was then successfully treated with antibiotics. Since the first Mitra-Clip implantation in 2003, only 19 cases of endocarditis have previously been reported. This article proposes a review of theses case-reports and a collection of their relevant clinical, echocardiographic and microbiological characteristics, the delivered therapies and their outcomes. These data contribute to a humble discussion around the main stakes of the disease, which are the prevention, the diagnosis, the involved bacteria's type, the prognosis and the treatments with a focus on the question of the recourse to surgical management.

Long-term results of the edge-to-edge repair for failed mitral valve repair as a bailout option

OBJECTIVE

We evaluate the long-term clinical and echocardiographic outcomes of edge-to-edge (E2E) repair combined with mitral annuloplasty in our institute with degenerative mitral regurgitation (MR) up to 10 years.

METHODS

Twenty-six consecutive patients undergoing E2E mitral repair after failure of other conventional mitral repair technique. There were 16 (61.5%) male and the mean age was 52.2 ± 10.4 years. Mitral regurgitation was due to anterior leaflet prolapse in 12 (46.2%) patients, bileaflet prolapse in 9 (34.6%), and multiple segment posterior leaflet prolapse in 5 (19.2%).

RESULTS

There were no perioperative deaths. Follow-up was 100% complete. The mean length of follow-up was 8.7 ± 0.9 years (median 8.4 years, 6.8-10.1 years). Two patients required reoperation of the MV. The freedom from reoperation and ≥ Moderate MR at 10 years was 69.9 ± 11.7%. The freedom from reoperation, ≥ Moderate MR and mitral stenosis (MS) at 10 years was (59.6 ± 10.0) %. The mean transmitral pressure gradient (TMPG) was 6.1 ± 2.5 mmHg, which was significantly elevated compared with preoperative TTE (P = 0.004). The freedom from ≥ Moderate MS at 10 years was 76.9 ± 8.3%. There were no differences between patients with and without MS at follow-up regarding the echocardiographic parameters and clinical status.

CONCLUSION

There is a slowly progressive elevation of TMPG after E2E mitral repair, while mildly elevated TMPG can be tolerated in most patients. In appropriate patients, the E2E repair combined with annuloplasty provides an effective "bailout" choice.

Loop technique with ink-dot marking test: An alternative strategy to the ink test

Objective

We assessed the long-term outcomes of the loop technique with the ink-dot marking test, an alternative to the ink test for aligning the mitral valve (MV) leaflet height, during MV repair.

Methods

We retrospectively reviewed 351 patients who underwent MV repair with the loop technique via median sternotomy or right mini-thoracotomy. The ink-dot marking test involves creation of a dotted line between the rough and clear zones in the anterior leaflet and the center of the posterior leaflet by gentian violet. According to this marking, we adjusted the fixing position of the loops with or without the loop-in-loop technique and additional neochordal repair.

Results

This study involved 141 women and 210 men (mean age, 63.7 ± 13.0 years). Forty-one patients required additional adjustment after the ink-dot marking test. No significant differences were found in the need for second arrest between patients who did and did not require additional adjustment after the ink-dot marking test (3 vs 32 patients, P = .782). Predischarge transthoracic echocardiography showed trivial residual MV regurgitation (MR) in 285 patients, mild in 64, and moderate in 2. Ten patients needed reoperations (9 MV replacements and 1 MV re-repair) because of recurrent MR during postoperative follow-up. The 3-, 5-, and 10-year postoperative cumulative incidence of moderate to severe recurrent MR was 3.6%, 6.0%, and 19.8%, respectively.

Conclusions

The loop technique with the ink-dot marking test provided good early and long-term results. This test may help to decrease residual MR, especially when using the loop technique.

Elevated gradient after mitral valve repair: The effect of surgical technique and relevance of postoperative atrial fibrillation

OBJECTIVES

We sought to investigate the effect of surgical technique in mitral valve repair on postoperative transmitral gradient (PTMG) and the relationship between PTMG and postoperative atrial fibrillation (AF).

METHODS

In this retrospective study, 390 patients who underwent mitral valve repair for degenerative mitral regurgitation without AF were included. PTMG was measured using transthoracic echocardiography before patient discharge. At follow-up, occurrences of AF within 6 months of surgery (early AF) and 6 months after surgery (late AF), as well as clinical and echocardiographic data were documented and investigated.

RESULTS

The in-hospital mortality was 0, and the mean gradient was 3.1 ± 1.2 mm Hg before patient discharge. The risks for higher PTMG included cleft closure, edge-to-edge technique, full ring annuloplasty, and smaller indexed prosthetic size (P < .05 for all). After a median follow-up of 46 months, stable sinus rhythm was maintained in 73.1% of the overall cohort and early AF occurred in 22.7% of patients. A total of 32 patients (8.5%) had late AF, which was significantly associated with PTMG (odds ratio, 3.93; P = .004). The minimum P value approach identified a mean gradient of ≥4.5 mm Hg as the best threshold for predicting late AF (χ² = 40.704; P < .001).

CONCLUSIONS

Patients who undergo mitral valve repair for degenerative mitral insufficiency might benefit from modification of the existing leaflet repair and annuloplasty techniques to achieve a lower PTMG level, which is associated with a decreased incidence of late AF during midterm follow-up.

Infective endocarditis following transcatheter edge-to-edge mitral valve repair: A systematic review

OBJECTIVES

To assess the clinical characteristics, management, and outcomes of patients diagnosed with infective endocarditis (IE) after edge-to-edge mitral valve repair with the MitraClip device.

BACKGROUND

Transcatheter edge-to-edge mitral valve repair has emerged as an alternative to surgery in high-risk patients. However, few data exist on IE following transcatheter mitral procedures.

METHODS

Four electronic databases (PubMed, Google Scholar, Embase, and Cochrane Library) were searched for original published studies on IE after edge-to-edge transcatheter mitral valve repair from 2003 to 2017.

RESULTS

A total of 10 publications describing 12 patients with definitive IE (median age 76 years, 55% men) were found. The mean logistic EuroSCORE/EuroSCORE II were 41% and 45%, respectively. The IE episode occurred early (within 12 months post-procedure) in nine patients (75%; within the first month in five patients). Staphylococcus aureus was the most frequent (60%) causal microorganism, and severe mitral regurgitation was present in all cases but one. Surgical mitral valve replacement (SMVR) was performed in most (67%) patients, and the mortality associated with the IE episode was high (42%).

CONCLUSIONS

IE following transcatheter edge-to-edge mitral valve repair is a rare but life-threatening complication, usually necessitating SMVR despite the high-risk profile of the patients. These results highlight the importance of adequate preventive measures and a prompt diagnosis and treatment of this serious complication.

Management of Incomplete Initial Repair in the Treatment of Degenerative Mitral Insufficiency

We sought to present our institutional protocol to manage incomplete initial repair of degenerative mitral regurgitation and to evaluate its mid-term outcomes. Eight hundred and fifteen patients with degenerative mitral insufficiency undergoing mitral valve repair were investigated in this study. The initial repair attempt was incomplete in 48 patients, leaving a degree of residual regurgitation > mild, and an elevated transmitral gradient or systolic anterior motion (SAM). These patients were further treated with medication or mitral valve re-repair or replacement under reinstituted cardiopulmonary bypass. Transesophageal echocardiographic reports and operational records were reviewed to identify morphological causes and establish management of incomplete initial repair. Mid-term outcomes of patients with re-repair and complete initial repair were evaluated and compared. Residual mitral regurgitation > mild was detected in 25 patients, an elevated transmitral gradient was detected in seven patients, and SAM was detected in 16 patients. The condition of eight patients with SAM was resolved with medication only. Mitral valve re-repair was performed in 23 patients and replacement was performed in 17, with comparable early mortality and morbidity. At 60.3 ± 25.5 months after surgery, late mitral stenosis and reoperation rate were significantly higher in re-repair patients than in patients with complete initial repair, despite comparable survival, left chamber reverse remodeling, and degree of residual regurgitation. Based on our institutional protocol, acceptable outcomes can be achieved for patients with incomplete initial mitral valve repair. Management should be tailored based on the characteristics of the mitral valve complex, expected repair durability, and operative risk.

A prospective study examining the role of myocardial Fibrosis in outcome following mitral valve repair IN DEgenerative mitral Regurgitation: rationale and design of the mitral FINDER study

Background

The optimal management of chronic severe primary degenerative mitral regurgitation (MR) is to repair the valve but identification of the optimal timing of surgery remains challenging. Current guidelines suggest ‘watchful waiting’ until the onset of symptoms or left ventricular (LV) dysfunction but these have been challenged as promoting ‘rescue surgery’. Better predictors are required to inform decision-making in relation to the necessity and timing of surgery. Chronic volume overload is a stimulus for adverse adaptive LV remodelling. Subclinical reduction in LV strain before mitral repair predicts a fall in LV ejection fraction following surgery and is thought to reflect the development of myocardial fibrosis in response to chronic volume overload. Myocardial fibrosis can be detected non-invasively using cardiac magnetic resonance (CMR) imaging techniques as an expansion of the extracellular volume (ECV).

Methods/design

This study investigates whether: 1) patients with above median ECV will have smaller reduction in end-systolic volume index (as a measure of the degree of reverse LV remodelling) on CMR following mitral valve repair, compared to those with below median ECV; and 2) higher ECV on CMR, validated through histology, adversely impacts upon post-operative complications and symptomatic improvement following surgery.

This is a multi-centre, prospective, cross-sectional comparison of patients prior to and 9 months following surgery for chronic severe primary degenerative MR. To establish the natural history of ECV in MR, an additional cohort of patients with asymptomatic MR who do not wish to consider early repair will be followed. Investigations include CMR, cardiopulmonary exercise test, stress echocardiography, signal-averaged electrocardiogram, 24-h electrocardiogram monitoring, laboratory tests and patient-reported outcome measures. Patients undergoing surgery will have cardiac biopsies performed at the time of mitral valve repair for histological quantification of fibrosis.

Discussion

This study will advance our understanding of ventricular remodelling in MR, its impact on patient symptoms and ventricular response following surgery. Establishing the link between myocardial fibrosis (measured on CMR and validated through histology), with early ventricular dysfunction, will offer physicians a novel non-invasive biomarker that can further inform the timing of surgery.

Trial registration

This trial was registered at ClinicalTrials.gov (NCT02355418) on 30th November 2015.

Mitral valve repair for degenerative mitral valve disease: surgical approach, patient selection and long-term outcomes

Mitral valve repair (MVRepair) has become the procedure of choice to correct severe degenerative mitral regurgitation (MR), due to its documented superiority to valve replacement regarding long-term survival, freedom from valve-related adverse events and preservation of left ventricular (LV) function. The refinement of MVRepair techniques has rendered almost all valves (more than 95%) amenable to repair with a 15-year freedom from reoperation of 90%. The concept of 'centres of excellence for MVRepair' has emerged, encouraging referring doctors to select the most experienced institutions or individual surgeons to deal with the most complex cases, based on repair volume, appropriate peri-procedural imaging and data regarding expected outcomes (repair, mortality and durability of repair). Based on the good results, operating on asymptomatic patients with severe MR is now widely accepted, prophylactically avoiding the dire consequences of chronic MR, such as LV function deterioration/enlargement, and development of atrial fibrillation and pulmonary hypertension. In reference centres, where the repair rate is over 95% for all types of disease with <1% mortality, it has become standard practice in nearly 50%-60% of all patients submitted to MVRepair. Finally, recent advances in the surgical treatment with the purpose of reducing invasiveness and surgical trauma, through partial sternotomy or mini-thoracotomy (video-assisted with or without robotics), are now being increasingly performed in 20%-30% of centres, claiming comparable results to conventional surgery. In addition, transcatheter technology, particularly the MitraClip, is evolving and treading its way in the treatment of high-risk patients with severe MR, but the results are still short of ideal.

Mitral clip - looking back and moving forward

PURPOSE OF REVIEW

Guidelines indicate surgical intervention for patients with symptomatic severe mitral regurgitation or signs of left ventricular dilatation or dysfunction. However, many patients do not receive surgery because of age or comorbidities, and have poor outcomes with conservative therapy. Transcatheter mitral repair with MitraClip (Abbott Vascular, IL, USA) has recently emerged as a viable treatment option for high-risk patients with heart failure. This article will review current evidence supporting the use of MitraClip across the spectrum of patient risk and discuss future directions for this technology.

RECENT FINDINGS

Both randomized and registry studies have demonstrated the efficacy and safety of MitraClip for mitral regurgitation reduction, with significant improvements in functional class and reductions in heart failure hospitalizations. With increasing global experience, a broader scope of patients and diseases can now be successfully treated, ranging from patients with failed surgical annuloplasty rings to those in cardiogenic shock. Ongoing randomized trials will further define the role of MitraClip in the management of heart failure patients with secondary mitral regurgitation.

SUMMARY

MitraClip is a useful therapeutic tool for nonsurgical patients with advanced heart failure and severe mitral regurgitation. Further developments in device design and procedural technique will continue to expand the range of patients who can be treated, with a goal of reducing heart failure hospitalizations and improving quality of life.

Durability of mitral valve repair for mitral regurgitation due to degenerative mitral valve disease

Degenerative diseases of the mitral valve (MV) are the most common cause of mitral regurgitation in the Western world and the most suitable pathology for MV repair. Several studies have shown excellent long-term durability of MV repair for degenerative diseases. The best follow-up results are obtained with isolated prolapse of the posterior leaflet, however even with isolated prolapse of the anterior leaflet or prolapse of both leaflets the results are gratifying, particularly in young patients. The freedom from reoperation on the MV at 15 years exceeds 90% for isolated prolapse of the posterior leaflet and it is around 70-85% for prolapse of the anterior leaflet or both leaflets. The degree of degenerative change in the MV also plays a role in durability of MV repair. Most studies have used freedom from reoperation to assess durability of the repair but some studies that examined valve function late after surgery suggest that recurrent mitral regurgitation is higher than estimated by freedom from reoperation. We can conclude that MV repair for degenerative mitral regurgitation is associated with low probability of reoperation for up to two decades after surgery. However, almost one-third of the patients develop recurrent moderate or severe mitral regurgitation suggesting that surgery does not arrest the degenerative process.

Therapeutic decision-making for patients with fluctuating mitral regurgitation

Mitral regurgitation (MR) is a common, progressive, and difficult-to-manage disease. MR is dynamic in nature, with physiological fluctuations occurring in response to various stimuli such as exercise and ischaemia, which can precipitate the development of symptoms and subsequent cardiac events. In both chronic primary and secondary MR, the dynamic behaviour of MR can be reliably examined during stress echocardiography. Dynamic fluctuation of MR can also have prognostic value; patients with a marked increase in regurgitant volume or who exhibit increased systolic pulmonary artery pressure during exercise have lower symptom-free survival than those who do not experience significant changes in MR and systolic pulmonary artery pressure during exercise. Identifying patients who have dynamic MR, and understanding the mechanisms underlying the condition, can potentially influence revascularization strategies (such as the surgical restoration of coronary blood flow) and interventional treatment (including cardiac resynchronization therapy and new approaches targeted to the mitral valve).