Contemporary outcomes in reoperative mitral valve surgery

Tissue versus mechanical mitral valve replacement in patients aged 50-70: a propensity-matched analysis

OBJECTIVES

There remains debate over the optimal mitral valve replacement (MVR) option for patients aged 50-70 years. The objective of this study was to retrospectively compare the long-term outcomes of mechanical and bioprosthetic MVR in this patient population.

METHODS

Data from patients undergoing MVR between 2004 and 2018 were retrospectively reviewed. The primary outcome was all-cause mortality. Secondary outcomes included perioperative and late morbidity.

RESULTS

Two hundred and eight-six propensity-matched patients (n = 143 mechanical; n = 143 bioprosthetic) aged 50-70 years were included in the final analysis. Maximum follow-up was 15.8 years. There was no significant difference in all-cause mortality between the groups at 30 days, 1 year, 5 years, 10 years, and at the longest follow-up. Patients who underwent mechanical MVR experienced significantly lower rates of postoperative atrial fibrillation (P = 0.001). There were no significant differences in rates of sepsis, acute kidney injury, superficial and deep sternal wound infection, mediastinal bleeding, and permanent pacemaker implantation. At the longest follow-up, there were no differences in myocardial infarction, stroke, heart failure or overall rehospitalization. At the same time point, there was an increased rate of MVR in patients receiving a bioprosthetic valve (P = 0.015).

CONCLUSIONS

Survival following mechanical and bioprosthetic MVR in patients 50-70 years of age is similar to up to 15 years of follow-up. Bioprosthetic MVR is associated with an increased risk of repeat MVR. Mechanical MVR is not associated with an increased risk of stroke. Valve selection in this patient population requires diligent consideration of structural valve deterioration and subsequent reoperation risk as well as bleeding and thromboembolic risk.

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

AIMS

We aimed to evaluate transcatheter mitral valve implantation (TMVI) using predominantly balloon-expandable transcatheter heart valves (THV) in patients with a landing zone for a percutaneously delivered prosthesis.

BACKGROUND

Patients with a degenerated mitral valve bioprosthesis, annuloplasty ring, and mitral annulus calcification (MAC) considered at high surgical risk currently represent a treatment challenge. TMVI is an alternative treatment option.

METHODS

Retrospective analysis of patients with symptomatic degenerated mitral valve bioprosthesis, or annuloplasty ring, and MAC treated with TMVI between November 2011 and April 2021. Endpoints were defined according to Mitral Valve Academic Research Consortium (MVARC) criteria and included device and procedure success at 30 days as well as mortality at 30 days and 1 year after the procedure.

RESULTS

A total of 77 patients underwent TMVI (valve in valve [ViV = 56], valve in ring [ViR = 11], and valve in MAC [ViMAC = 10]). There was a trend toward higher technical success (all = 93.5%, ViV = 96.4%, ViR = 90.9%, ViMAC = 80%, p = 0.06) and lower 30-day (all = 11.7%, ViV = 10.7%, ViR = 9.1%, ViMAC = 20%, p = 0.49) and 1-year mortality (all = 26%, ViV = 23.2%, ViR = 27.3%, ViMAC= 40%, p = 0.36) after ViV and ViR compared to ViMAC.

CONCLUSION

TMVI represents a reasonable treatment option in selected patients with MAC or who are poor candidates for redo mitral valve surgery. Technical success and survival up to 1 year were not significantly dependent on the subgroup in which TMVI was performed.

Mitral valve replacement in young patients: review and current challenges

Mitral valve repair is the ideal intervention for mitral valve disease with excellent long-term survival comparable to the age-matched general population. When the mitral valve is not repairable, mechanical prostheses may be associated with improved survival as compared with biological prostheses. Newer mechanical and biological valve prostheses have the potential to improve outcomes following mitral valve replacement in young patients. Patients presenting for mitral valve surgery after failed transcatheter mitral valve-in-valve have high rates of postoperative mortality and morbidity, exceeding those seen with reoperative mitral valve surgery, which poses issues in young patients who have a higher cumulative incidence of reintervention.

Expanding treatment horizons: transcatheter mitral valve-in-valve replacement in bridging to heart transplant

Transcatheter mitral valve (MV) replacement is an option in complex MV disease with potentially more predictable treatment outcomes and less invasiveness that increases the treatment spectrum to high-risk or non-surgical patients. We present an interesting case of failed MV bioprosthesis who presented with progressively worsening heart failure for heart transplant evaluation, but was successfully managed with transcatheter mitral valve-in-valve replacement (TMViVR). This case illustrates the pivotal role of TMViVR utilization in addressing complex cardiac scenarios, particularly when re-operative surgical MV replacement poses a high risk and also bridging the gap between the present and future heart transplantation preparations by paving the way for a well-prepared patient in the subsequent phase. The lifetime disease management and patient-centric approach with meticulous risk assessment reinforces the importance of shared decision-making in complex cases.

Mechanical Valves: Past, Present, and Future-A Review

The mechanical valve was first invented in the 1950s, and since then, a wide variety of prostheses have been developed. Although mechanical valves have outstanding durability, their use necessitates life-long treatment with anticoagulants, which increases the risk of bleeding and thromboembolic events. The current guidelines recommend a mechanical prosthetic valve in patients under 50-60 years; however, for patients aged 50-70 years, the data are conflicting and there is not a clear-cut recommendation. In recent decades, progress has been made in several areas. First, the On-X mechanical valve was introduced; this valve has a lower anticoagulant requirement in the aortic position. Second, a potential alternative to vitamin K-antagonist treatment, rivaroxaban, has shown encouraging results in small-scale trials and is currently being tested in a large randomized clinical trial. Lastly, an innovative mechanical valve that eliminates the need for anticoagulant therapy is under development. We attempted to review the current literature on the subject with special emphasis on the role of mechanical valves in the current era and discuss alternatives and future innovations.

Mortality and resource utilization in surgical versus transcatheter repeat mitral valve replacement: A national analysis

BACKGROUND

Transcatheter mitral valve replacement (TMVR) has garnered interest as a viable alternative to the traditional surgical mitral valve replacement (SMVR) for high-risk patients requiring redo operations. This study aims to evaluate the association of TMVR with selected clinical and financial outcomes.

METHODS

Adults undergoing isolated redo mitral valve replacement were identified in the 2016-2020 Nationwide Readmissions Database and categorized into TMVR or SMVR cohorts. Various regression models were developed to assess the association between TMVR and in-hospital mortality, as well as additional secondary outcomes. Transseptal and transapical catheter-based approaches were also compared in relation to study endpoints.

RESULTS

Of an estimated 7,725 patients, 2,941 (38.1%) underwent TMVR. During the study period, the proportion of TMVR for redo operations increased from 17.8% to 46.7% (nptrend<0.001). Following adjustment, TMVR was associated with similar odds of in-hospital mortality (AOR 0.82, p = 0.48), but lower odds of stroke (AOR 0.44, p = 0.001), prolonged ventilation (AOR 0.43, p<0.001), acute kidney injury (AOR 0.61, p<0.001), and reoperation (AOR 0.29, p = 0.02). TMVR was additionally correlated with shorter postoperative length of stay (pLOS; β -0.98, p<0.001) and reduced costs (β -$10,100, p = 0.002). Additional analysis demonstrated that the transseptal approach had lower adjusted mortality (AOR 0.44, p = 0.02), shorter adjusted pLOS (β -0.43, p<0.001), but higher overall costs (β $5,200, p = 0.04), compared to transapical.

CONCLUSIONS

In this retrospective cohort study, we noted TMVR to yield similar odds of in-hospital mortality as SMVR, but fewer complications and reduced healthcare expenditures. Moreover, transseptal approaches were associated with lower adjusted mortality, shorter pLOS, but higher cost, relative to the transapical. Our findings suggest that TMVR represent a cost-effective and safe treatment modality for patients requiring redo mitral valve procedures. Nevertheless, future studies examining long-term outcomes associated with SMVR and TMVR in redo mitral valve operations, are needed.

Contemporary 1-Year Outcomes of Mitral Valve-in-Ring With Balloon-Expandable Aortic Transcatheter Valves in the U.S

BACKGROUND

Adequate valve performance after surgical mitral valve repair with an annuloplasty ring is not always sustained over time. The risk of repeat mitral valve surgery may be high in these patients. Transcatheter mitral valve-in-ring (MViR) is emerging as an alternative for high-risk patients.

OBJECTIVES

The authors sought to assess contemporary outcomes of MViR using third-generation balloon-expandable aortic transcatheter heart valves.

METHODS

Patients who underwent MViR and were enrolled in the STDS/ACC TVT (Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy) Registry between August 2015 and December 2022 were analyzed.

RESULTS

A total of 820 patients underwent MViR at 236 sites, mean age was 72.2 ± 10.4 years, 50.9% were female, mean STS score was 8.2% ± 6.9%, and most (78%) were in NYHA functional class III to IV. Mean left ventricular ejection fraction was 47.8% ± 14.2%, mean mitral gradient was 8.9 ± 7.0 mm Hg, and 75.5% had ≥ moderate mitral regurgitation. Access was transseptal in 93.9% with 88% technical success. All-cause mortality at 30 days was 8.3%, and at 1 year, 22.4%, with a reintervention rate of 9.1%. At 1-year follow-up, 75.6% were NYHA functional class I to II, Kansas City Cardiomyopathy Questionnaire score increased by 25.9 ± 29.1 points, mean mitral valve gradient was 8.4 ± 3.4 mm Hg, and 91.7% had ≤ mild mitral regurgitation.

CONCLUSIONS

MViR with third-generation balloon-expandable aortic transcatheter heart valves is associated with a significant reduction in mitral regurgitation and improvement in symptoms at 1 year, but with elevated valvular gradients and a high reintervention rate. MViR is a reasonable alternative for high-risk patients unable undergo surgery who have appropriate anatomy for the procedure. (STS/ACC TVT Registry Mitral Module [TMVR]; NCT02245763).

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.

Transcatheter mitral valve implantation versus conventional redo surgery for degenerated mitral valve prostheses and rings in a multicenter registry

OBJECTIVES

Degeneration of mitral prostheses/rings may be treated by redo surgery, and, recently, by transcatheter valve-in-valve/ring implantation. This multicenter registry presents results of transcatheter valve-in-valve and repeat surgery for prostheses/rings degeneration.

METHODS

Data provided by 10 German heart centers underwent propensity score-matched retrospective analysis. The primary endpoint was 30-day/midterm mortality. Perioperative outcome was assessed according to the Mitral Valve Academic Research Consortium criteria. Further, the influence of moderate or greater tricuspid regurgitation (TR) on 30-day/midterm mortality was analyzed.

RESULTS

Between 2014 and 2019, 273 patients (79 transcatheter mitral valve-in-valve [TM-ViV] and 194 redo mitral valve replacement [Re-MVR]) underwent repeat procedure for mitral prosthesis/ring degeneration. Propensity score matching distinguished 79 patient pairs. European System for Cardiac Operative Risk Evaluation (EuroSCORE) II-predicted risk was 15.7 ± 13.7% in the TM-ViV group and 15.0% ± 12.7% in the Re-MVR group (P = .5336). TM-ViV patients were older (74.73 vs 72.2 years; P = .0030) and had higher incidence of atrial fibrillation (54 vs 40 patients; P = .0233). Severe TR incidence was similar (17.95% in TM-ViV vs 14.10%; P = .1741). Sixty-eight TM-ViV patients previously underwent mitral valve replacement, whereas 41 Re-MVR patients underwent valve repair (P < .0001). Stenosis was the leading degeneration mechanism in 42 TM-ViV versus 22 Re-MVR patients (P < .0005). The 30-day/midterm mortality did not differ between groups. Moderate or greater TR was a predictor of total (odds ratio [OR], 4.36; P = .0011), 30-day (OR, 3.76; P = .0180), and midterm mortality (OR, 4.30; P = .0378), irrespective of group.

CONCLUSIONS

In both groups, observed mortality was less than predicted. Redo surgery enabled treatment of concomitant conditions, such as atrial fibrillation or TR. TR was shown to be a predictor of total, 30-day, and midterm mortality in both groups.

Transcatheter Aortic Valve Implantation to Treat Degenerated Aortic, Mitral and Tricuspid Bioprosthesis

Transcatheter aortic valve implantation (TAVI) is now well established as the treatment of choice for patients with native aortic valve stenosis who are high or intermediate risk for surgical aortic valve replacement. Recent data has also supported the use of TAVI in patients at low surgical risk and also in anatomical subsets that were previously felt to be contra-indicated including bicuspid aortic valves and aortic regurgitation. With advancements and refinements in procedural techniques, the application of this technology has now been further expanded to include the management of degenerated bioprosthesis. After the demonstration of feasibility and safety in the management of degenerated aortic bioprosthetic valves, mitral and tricuspid bioprosthetic valve treatment is now also well-established and provides an attractive alternative to performing redo surgery. In this review, we appraise the latest clinical evidence and highlight procedural considerations when utilising TAVI technology in the management of degenerated aortic, mitral or tricuspid prosthesis.

Cardiac Reoperation or Transcatheter Mitral Valve Replacement for Patients With Failed Mitral Prostheses

BACKGROUND

Evidence is limited regarding patient outcomes comparing redo surgical mitral valve replacement (redo SMVR) vs transcatheter mitral valve replacement (TMVR) for failed prostheses.

OBJECTIVES

The goal of this study was to compare the outcomes of redo SMVR vs TMVR in patients with failed prostheses, as well as evaluate the association between case volume and outcomes.

METHODS

Medicare beneficiaries aged ≥65 years who underwent redo SMVR or TMVR for failed mitral prostheses between 2016 and 2020 were included. The primary endpoint was mid-term (up to 3 years) major adverse cardiovascular events (MACE), including all-cause death, heart failure rehospitalization, stroke, or reintervention. Propensity score-matched analysis was used.

RESULTS

A total of 4,293 patients were included (redo SMVR: 64%; TMVR: 36%). TMVR recipients were older, with a higher comorbidity burden. In matched cohort (n = 1,317 in each group), mid-term risk of MACE was similar (adjusted HR: 0.92; 95% CI: 0.80-1.04; P = 0.2). However, landmark analysis revealed a lower risk of MACE with TMVR in the first 6 months (adjusted HR: 0.75; 95% CI: 0.63-0.88; P < 0.001) albeit with a higher risk beyond 6 months (adjusted HR: 1.28; 95% CI: 1.04-1.58; P = 0.02). Increasing procedural volume was associated with decreased risk of mid-term MACE after redo SMVR (P = 0.001) but not after TMVR (P = 0.3).

CONCLUSIONS

In this large cohort of Medicare beneficiaries with failed mitral prostheses, outcomes were similar between redo SMVR and TMVR at 3 years, with TMVR showing a lower initial risk but a higher risk of MACE after 6 months. These findings highlight the importance of striking a balance between surgical risk, anticipated longevity, and hospital expertise when selecting interventions.

Urgent Transcatheter Mitral Valve-in-Valve Replacement With Venoarterial Extracorporeal Membrane Oxygenation Support: Case Report and Review of the Literature

Critical mitral valve stenosis due to a failed bioprosthetic valve is associated with significant morbidity and mortality, with the transcatheter Valve-in-Valve (ViV) approach becoming a popular treatment option. We present a case of cardiogenic shock secondary to a stenotic mitral bio-prosthetic valve. The Heart team was consulted; the patient was a high-risk surgical candidate for valve replacement. He required venoarterial extracorporeal membrane oxygenation as a bridge to definitive therapy. The patient underwent a successful urgent transcatheter mitral ViV procedure with a trans-septal approach. Follow-up echocardiography showed significant improvement in mitral valve dynamics. Recently emerging transcatheter approaches for mitral ViV implantation after balloon valvuloplasty into a failed mitral valve prosthesis are technically feasible in high-risk patient populations and should be considered over re-operative mitral valve surgery.

Outcomes of minimally invasive versus conventional sternotomy for redo mitral valve surgery according to Mitral Valve Academic Research Consortium: A systematic review and meta-analysis

A minimally invasive approach through right mini-thoracotomy for redo mitral valve surgery may improve patients' outcomes compared to median sternotomy. This study aims to evaluate the outcomes of both procedures according to the Mitral Valve Academic Research Consortium (MVARC). This systematic review and meta-analysis were performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). Literature searching was performed in several databases including PubMed, EBSCOhost, Scopus, and Proquest up to 28 February 2022. Meta-analysis using proportions or means was applied. A total of 13 retrospective cohort articles were included in this study. The incidence of in-hospital mortality (3% vs 9.2%, OR = 0.35; 95% CI: 0.21-0.58; P ≤ 0.0001), reintervention for bleeding (3.8% vs 5.9%, OR = 0.56; 95% CI: 0.32-0.97; P = 0.04), and acute renal failure (5% vs 12%, OR = 0.29; 95% CI: 0.23-0.65; P = 0.0003) was significantly lower in mini-thoracotomy (MINI) group compared to median sternotomy (STER) group. The incidence of neurologic events (3.4% vs 5.5%, OR = 0.66; 95% CI: 0.4-1.08; P = 0.1) and arrhythmia (19.5% vs 25.5%, OR = 0.64; 95% CI: 0.38-1.09; P = 0.1) were also lower in MINI group compared to STER group but was not significant statistically. No significant differences were found in myocardial infarct (1% vs 1%, OR = 0.71; 95% CI: 0.06-8.85; P = 0.79) between MINI and STER group. A minimally invasive surgery through right mini-thoracotomy is associated with a lower incidence of in-hospital mortality, reintervention for bleeding, and acute renal failure. It is a safe alternative to median sternotomy for redo mitral valve surgery.

What determines outcomes in multivalve reoperations? Effect of patient and surgical complexity

OBJECTIVE

Patient characteristics, risks, and outcomes associated with reoperative multivalve cardiac surgery are poorly characterized. Effect of patient variables and surgical components of each reoperation were evaluated with regard to operative mortality.

METHODS

From January 2008 to January 2022, 2324 patients with previous cardiac surgery underwent 2352 reoperations involving repair or replacement of multiple cardiac valves at Cleveland Clinic. Mean age was 66 ± 14 years. Number of surgical components representing surgical complexity (valve procedures, aortic surgery, coronary artery bypass grafting, and atrial fibrillation procedures) ranged from 2 to 6. Random forest for imbalanced data was used to identify risk factors for operative mortality.

RESULTS

Surgery was elective in 1327 (56%), urgent in 1006 (43%), and emergency in 19 (0.8%). First-time reoperations were performed in 1796 (76%) and 556 (24%) had 2 or more previous operations. Isolated multivalve operations comprised 54% (1265) of cases; 1087 incorporated additional surgical components. Two valves were operated on in 80% (1889) of cases, 3 in 20% (461), and 4 in 0.09% (2). Operative mortality was 4.2% (98 out of 2352), with 1.7% (12 out of 704) for elective, isolated multivalve reoperations. For each added surgical component, operative mortality incrementally increased, from 2.4% for 2 components (24 out of 1009) to 17% for ≥5 (5 out of 30). Predictors of operative mortality included coronary artery bypass grafting, surgical urgency, cardiac, renal dysfunction, peripheral artery disease, New York Heart Association functional class, and anemia.

CONCLUSIONS

Elective, isolated reoperative multivalve surgery can be performed with low mortality. Surgical complexity coupled with key physiologic factors can be used to inform surgical risk and decision making.

Reoperation after failure of mitral valve repair for degenerative disease: A single surgeon experience

Background

With an increasing number of patients undergoing mitral valve repair, more patients are presenting for reoperation. This study aimed to evaluate factors influencing mortality and survival of patients undergoing reoperation for mitral valve surgery after previous mitral valve repair under a single surgeon.

Methods

We retrospectively collected data from 117 patients who underwent reoperation after previous mitral valve repair between 2010 and 2022. We aimed to identify preoperative, operative, and postoperative factors affecting outcomes. The primary outcome was overall survival, and the secondary outcomes included prolonged hospital stay and in-hospital mortality. The mean follow-up was 9.13 ± 10.36 years (median, 6.50 years).

Results

Out of 117 patients, 85 underwent mitral valve replacement (MVR) and 32 underwent mitral valve repair (MVr). The mean age was 64.7 ± 12.7 years (65.5 ± 12.2 years in the MVR group and 62.7 ± 14.0 years in the MVr group), and 66 (56.4%) were men. On a standard multivariate analysis of the overall factors influencing mortality, advanced age was associated with a higher risk of overall mortality (hazard ratio [HR], 1.07; 95% confidence interval [CI], f1.03-1.12; P = .001). The urgency of surgical intervention also played a role, with a higher risk of in-hospital mortality in patients undergoing emergency reoperation (HR, 1.55; 95% CI, 1.60-149.05; P = .02). Furthermore, the presence of mixed lesions, encompassing both mitral regurgitation and stenosis, was strongly linked to increased overall mortality (HR, 17.09; 95% CI, 4.06-71.94; P < .001) and in-hospital mortality (HR, 1.75; 95% CI, 15.83-1925.61; P < .001). Infective endocarditis emerged as a prominent risk factor for overall mortality (HR, 992.08; 95% CI, 85.74-11,479.08; P < .001) and in-hospital mortality (HR, 5.83; 95% CI, 514.81-65,932.99; P < .001). Additionally, chronic obstructive pulmonary disease was associated with a significantly increased risk of overall mortality (HR, 4.3; 95% CI, 1.24-14.97; P = .02).

Conclusions

Our single surgeon experience demonstrates that mitral valve reoperation after a previous repair is associated with good outcomes and survival.

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.

MitraClip used for severe mitral regurgitation after surgery for type A aortic dissection combined with Marfan syndrome

Mitral regurgitation is a rare but catastrophic condition in patients after surgery for type A aortic dissection. The second thoracotomy to complete the mitral valve operation could be fatal. Here, we report a case of severe mitral regurgitation treated with MitraClip in a 53-year-old woman after surgery for type A aortic dissection combined with Marfan syndrome. She was discharged uneventfully, and a significant reduction of regurgitation of mitral valve and tricuspid valve was observed at the 6-month follow-up. MitraClip could be an alternative device for such high-risk patients.

5-Year Prospective Evaluation of Mitral Valve-in-Valve, Valve-in-Ring, and Valve-in-MAC Outcomes: MITRAL Trial Final Results

BACKGROUND

The MITRAL (Mitral Implantation of Transcatheter Valves) trial is the first prospective trial to evaluate the safety and feasibility of balloon-expandable aortic transcatheter heart valves in patients with failed surgical bioprostheses or annuloplasty rings and severe mitral annular calcification treated with mitral valve-in-valve (MViV), valve-in-ring (MViR), or valve-in-mitral annular calcification (ViMAC).

OBJECTIVES

The aim of this study was to evaluate 5-year outcomes among these patients.

METHODS

A multicenter prospective study was conducted among patients at high surgical risk at 13 U.S. sites. Patients underwent MViV (n = 30), MViR (n = 30), or ViMAC (n = 31) and were followed annually for 5 years. Kansas City Cardiomyopathy Questionnaire scores were obtained at baseline and follow-up visits. Echocardiograms were analyzed at independent core laboratories.

RESULTS

A total of 91 patients underwent transcatheter mitral valve replacement (February 2015 to December 2017). The mean age was 74.3 ± 8.9 years. At 5-year follow-up, the lowest all-cause mortality was observed in the MViV group (21.4%), 94.7% of patients were in NYHA functional class I or II, and the mean mitral gradient was 6.6 ± 2.5 mm Hg. The MViR and ViMAC groups had higher all-cause mortality (65.5% and 67.9%), most survivors were in NYHA functional classes I and II (50% and 55.6%), and mean mitral gradients remained stable (5.8 ± 0.1 and 6.7 ± 2.5 mm Hg). Significant improvements in Kansas City Cardiomyopathy Questionnaire scores were observed when all 3 arms were pooled.

CONCLUSIONS

MViV, MViR, and ViMAC procedures were associated with sustained improvement of heart failure symptoms and quality of life among survivors at 5 years. Transcatheter heart valve function remained stable in all 3 groups. Patients treated with MViV had excellent survival at 5 years, whereas survival was lower in the MViR and ViMAC groups, consistent with underlying disease severity. Patients with more residual mitral regurgitation had higher mortality.

Transcatheter heart valve interventions for patients with rheumatic heart disease

Rheumatic heart disease [RHD] is the most prevalent cause of valvular heart disease in the world, outstripping degenerative aortic stenosis numbers fourfold. Despite this, global resources are firmly aimed at improving the management of degenerative disease. Reasons remain complex and include lack of resources, expertise, and overall access to valve interventions in developing nations, where RHD is most prevalent. Is it time to consider less invasive alternatives to conventional valve surgery? Several anatomical and pathological differences exist between degenerative and rheumatic valves, including percutaneous valve landing zones. These are poorly documented and may require dedicated solutions when considering percutaneous intervention. Percutaneous balloon mitral valvuloplasty (PBMV) is the treatment of choice for severe mitral stenosis (MS) but is reserved for patients with suitable valve anatomy without significant mitral regurgitation (MR), the commonest lesion in RHD. Valvuloplasty also rarely offers a durable solution for patients with rheumatic aortic stenosis (AS) or aortic regurgitation (AR). MR and AR pose unique challenges to successful transcatheter valve implantation as landing zone calcification, so central in docking transcatheter aortic valves in degenerative AS, is often lacking. Surgery in young RHD patients requires mechanical prostheses for durability but morbidity and mortality from both thrombotic complications and bleeding on Warfarin remains excessively high. Also, redo surgery rates are high for progression of aortic valve disease in patients with prior mitral valve replacement (MVR). Transcatheter treatments may offer a solution to anticoagulation problems and address reoperation in patients with prior MVR or failing ventricles, but would have to be tailored to the rheumatic environment. The high prevalence of MR and AR, lack of calcification and other unique anatomical challenges remain. Improvements in tissue durability, the development of novel synthetic valve leaflet materials, dedicated delivery systems and docking stations or anchoring systems to securely land the transcatheter devices, would all require attention. We review the epidemiology of RHD and discuss anatomical differences between rheumatic valves and other pathologies with a view to transcatheter solutions. The shortcomings of current RHD management, including current transcatheter treatments, will be discussed and finally we look at future developments in the field.

Transapical Mitral Valve-in-Ring Replacement Using the Innovative System under 3-Dimensional Printing Guidance

BACKGROUND

Transcatheter mitral valve-in-ring replacement (TMViR) is an emerging alternative for patients with recurrent mitral regurgitation (MR) after a prior failed annuloplasty ring. However, intraoperative common issues and complications remain to be addressed.

CASE SUMMARY

We describe the case of a 67-year-old male patient who underwent surgical mitral concomitant tricuspid annuloplasty repair 7 years ago who developed recurrent severe MR (New York Heart Association functional class IV). To avoid a high-risk surgical reoperation, we chose to perform a TMViR using an innovative dedicated device-the Mi-thos system-via a transapical approach. A patient-specific, 3-dimensional printed model was used to guide the procedure to avoid potential challenges. The procedure was performed successfully, and the patient exhibited symptomatic improvement.

CONCLUSIONS

This case report highlights the first use of the innovative Mi-thos system in a TMViR procedure. The findings demonstrate the feasibility and safety of utilizing the Mi-thos system, guided by 3-dimensional printing technology, for patients who have experienced recurrent mitral regurgitation MR following a failed annuloplasty ring.

Valve-in-valve transcatheter mitral valve replacement procedure in prosthetic valve stenosis

A patient presented with acute respiratory failure and shock due to severe prosthetic mitral valve stenosis. A valve-in-valve transcatheter mitral valve replacement procedure was performed via the transeptal approach due to his high-risk presentation with good results.

Low-Dose vs Standard Warfarin After Mechanical Mitral Valve Replacement: A Randomized Trial

BACKGROUND

Current guidelines recommend a target international normalized ratio (INR) range of 2.5 to 3.5 in patients with a mechanical mitral prosthesis. The Prospective Randomized On-X Anticoagulation Clinical Trial (PROACT) Mitral randomized controlled noninferiority trial assessed safety and efficacy of warfarin at doses lower than currently recommended in patients with an On-X (Artivion, Inc) mechanical mitral valve.

METHODS

After On-X mechanical mitral valve replacement, followed by at least 3 months of standard anticoagulation, 401 patients at 44 North American centers were randomized to low-dose warfarin (target INR, 2.0-2.5) or standard-dose warfarin (target INR, 2.5-3.5). All patients were prescribed aspirin, 81 mg daily, and encouraged to use home INR testing. The primary end point was the sum of the linearized rates of thromboembolism, valve thrombosis, and bleeding events. The design was based on an expected 7.3% event rate and 1.5% noninferiority margin.

RESULTS

Mean patient follow-up was 4.1 years. Mean INR was 2.47 and 2.92 (P <.001) in the low-dose and standard-dose warfarin groups, respectively. Primary end point rates were 11.9% per patient-year in the low-dose group and 12.0% per patient-year in the standard-dose group (difference, -0.07%; 95% CI, -3.40% to 3.26%). The CI >1.5%, thus noninferiority was not achieved. Rates (percentage per patient-year) of the individual components of the primary end point were 2.3% vs 2.5% for thromboembolism, 0.5% vs 0.5% for valve thrombosis, and 9.13% vs 9.04% for bleeding.

CONCLUSIONS

Compared with standard-dose warfarin, low-dose warfarin did not achieve noninferiority for the composite primary end point. (PROACT Clinicaltrials.gov number, NCT00291525).

Meta-Analysis Comparing Valve-in-Valve Transcatheter Mitral Valve Replacement Versus Redo Surgical Mitral Valve Replacement in Degenerated Bioprosthetic Mitral Valve

Valve-in-valve transcatheter mitral valve replacement (ViV-TMVR) and redo surgical mitral valve replacement (redo-SMVR) are 2 treatment strategies for patients with bioprosthetic mitral valve dysfunction. We conducted a systematic review and meta-analysis to compare the outcomes of ViV-TMVR versus redo-SMVR. We searched PubMed, EMBASE, Cochrane, and Google Scholar for studies comparing outcomes of ViV-TMVR versus redo-SMVR in degenerated bioprosthetic mitral valves. We used a random-effects model to calculate odd ratios (ORs) with 95% confidence intervals (CIs). Outcomes included in-hospital, 30-day, 1-year, and 2-year mortality, stroke, bleeding, acute kidney injury, arrhythmias, permanent pacemaker insertion, and hospital length of stay (LOS). A total of 6 observational studies with 707 subjects were included. The median follow-up was 2.7 years. Despite their older age and greater co-morbidity burden, patients who underwent ViV-TMVR had a similar in-hospital mortality (OR 0.52, 95% CI 0.22 to 1.23, p = 0.14), 30-day mortality (OR 0.65, 95% CI 0.36 to 1.17, p = 0.15), 1-year mortality (OR 0.97, 95% CI 0.63 to 1.49, p = 0.89), and 2-year mortality (OR 1.17, 95% CI 0.65 to 2.13, p = 0.60) compared with redo-SMVR. ViV-TMVR was associated with significantly lower periprocedural complications, including stroke, bleeding, acute kidney injury, arrhythmias, and permanent pacemaker insertion, and shorter hospital LOS than redo-SMVR. In conclusion, ViV-TMVR was associated with better outcomes than redo-SMVR in patients with degenerated bioprosthetic mitral valves, including lower complication rates and shorter hospital LOS, with no significant difference in mortality rates. Large-scale randomized trials are needed to mitigate biases and confirm our findings.

Transcatheter mitral valve replacement versus redo surgery for mitral prosthesis failure: A systematic review and meta-analysis

Background

Transcatheter mitral valve replacement (TMVR) has emerged as an alternative to redo surgery. TMVR compared with redo surgical mitral valve replacement (SMVR) in patients with mitral prosthesis failure remains limited. In this study, we performed a meta-analysis to assess the outcomes of TMVR (including valve-in-valve and valve-in-ring) versus redo surgery for mitral prosthesis failure.

Methods

We comprehensively searched the PubMed, Embase, and Cochrane library databases according to predetermined inclusion and exclusion criteria, and then we extracted data. We compared the outcomes of TMVR and redo SMVR for mitral prosthesis failure in terms of the in-hospital mortality, stroke, renal dysfunction, vascular complication, pacemaker implantation, exploration for bleeding, paravalvular leak, mean mitral valve gradient, 30-day mortality, and 1-year mortality.

Results

Nine retrospective cohort studies and a total of 3,038 patients were included in this analysis. Compared with redo SMVR for mitral prosthesis failure, TMVR was associated with lower in-hospital mortality [odds ratios (OR): 0.44; 95% confidence interval (CI): 0.30-0.64; P < 0.001], stroke (OR: 0.44; 95% CI: 0.29-0.67; P = 0.0001), renal dysfunction (OR: 0.52; 95% CI: 0.37-0.75; P = 0.0003), vascular complication (OR: 0.58; 95% CI: 0.43-0.78; P = 0.004), pacemaker implantation (OR: 0.23; 95% CI: 0.15-0.36; P < 0.00001), and exploration for bleeding (OR: 0.24; 95% CI: 0.06-0.96; P = 0.04). Conversely, redo SMVR had lower paravalvular leak (OR: 22.12; 95% CI: 2.81-174.16; P = 0.003). There was no difference in mean mitral valve gradient (MD: 0.04; 95% CI: -0.47 to 0.55; P = 0.87), 30-day mortality (OR: 0.65; 95% CI: 0.36-1.17; P = 0.15), and 1-year mortality (OR: 0.96; 95% CI: 0.63-1.45; P = 0.84).

Conclusion

In patients with mitral prosthesis failure, TMVR is associated with lower in-hospital mortality and lower occurrence of postoperative complications, except for paravalvular leak. TMVR offers a viable alternative to the conventional redo surgery in selected patients.

Transcatheter Mitral Valve Replacement in Failed Bioprosthetic Valve, Ring, and Mitral Annular Calcification Associated Mitral Valve Disease Using Balloon Expandable Transcatheter Heart Valve

Transcatheter mitral valve replacement (TMVR) using the SAPIEN platform has been performed in failed bioprosthetic valves (valve-in-valve), surgical annuloplasty rings (valve-in-ring), and native valves with mitral annular calcification (MAC) (valve-in-MAC). Experience over the past decade has identified important challenges and solutions to improve clinical outcomes. In this review, we discuss the indication, trend in utilization, unique challenges, procedural planning, and clinical outcomes of valve-in-valve, valve-in-ring, and valve-in-MAC TMVR.

Minimally Invasive Beating Heart Mitral Valve Repair in a Patient With Connective Tissue Disease at Prohibitive Risk for Redo Sternotomy

Sternal reentry when the ascending aorta is adherent to the posterior table of the sternum is associated with substantial risk. A minimally invasive right thoracotomy beating heart approach is an alternative when the aorta cannot be cross-clamped. This report details this technique for a complex reoperative mitral valve repair procedure performed in a patient with connective tissue disease who had required multiple aortic operations and presented with heart failure and severe functional mitral regurgitation.

Transcatheter valve-in-valve implantation versus redo surgical mitral valve replacement in patients with failed mitral bioprostheses

BACKGROUND

Data on the safety of valve-in-valve transcatheter mitral valve replacement (ViV-TMVR) compared with redo surgical mitral valve replacement (SMVR) in patients with a history of bioprosthetic mitral valve (MV) remain limited.

AIMS

We aimed to evaluate the in-hospital, 30-day and 6-month readmission outcomes of ViV-TMVR compared with redo-SMVR in a real-world cohort.

METHODS

The Nationwide Readmission Database was utilised, analysing data from 2015 to 2019. To determine the adjusted odds ratio (aOR), we used the propensity-matched analysis for major outcomes at index hospitalisation, 30 days, and 6 months during the episode of readmission.

RESULTS

A total of 3,691 patients were included, of these, 24.2% underwent ViV-TMVR and 75.8% underwent redo-SMVR. Patients undergoing ViV-TMVR were older with higher rates of comorbidities. The mean length of stay (15 days vs 4 days) and cost of hospitalisation ($76,558 vs $46,743) were significantly higher for redo-SMVR. The rate of in-hospital all-cause mortality was also significantly lower in ViV-TMVR (2.6% vs 7.3%). By contrast, 30-day all-cause mortality during the episode of readmission (aOR 1.01, 95% confidence interval [CI]: 0.40-2.55) and all-cause readmission rates (aOR 0.82, 95% CI: 0.66-1.02) were similar between both groups. The incidence of all-cause readmissions at 6 months (aOR 0.83, 95% CI: 0.65-1.05) and all-cause mortality during the episode of readmission at 6 months (aOR 1.84, 95% CI: 0.54-6.36) were also comparable. The utilisation of the ViV-TMVR procedure increased significantly during our study duration, from 5.2% to 36.8%, (ptrend<0.01).

CONCLUSIONS

ViV-TMVR is associated with lower odds of in-hospital mortality, complications, and resource utilisation. The all-cause readmissions and 30-day and 6-month mortality during the episode of readmissions were comparable between both groups.

The Evolution of Transcatheter Therapies for Mitral Valve Disease: From Mitral Valvuloplasty to Transcatheter Mitral Valve Replacement

The prevalence of mitral valve disease has evolved over the past 5 decades from primarily a disease of rheumatic origin to a disease affecting the aging population that encompasses a range of phenotypes from rheumatic mitral stenosis, degenerative mitral regurgitation, and degenerative mitral valve calcification to secondary mitral regurgitation. A reflection on the history of therapy for mitral valve disease is an expedition that follows the birth and development of structural heart intervention from the first percutaneous balloon mitral valvuloplasty to innovative technologies for transcatheter mitral valve repair and replacement. This review will lead you along this journey, pause to acknowledge the feats accomplished, and reflect on the road that lies ahead.

Transcatheter Mitral Valve-in-Valve Implantation with the Balloon-Expandable Myval Device

Background: The vast majority of transcatheter valve-in-valve (ViV) mitral procedures have been reported with the SAPIEN family. We aimed to report the preliminary experience with the Myval balloon-expandable device in this setting. Methods: Multicenter retrospective study of high-risk surgical patients with mitral bioprosthesis degeneration undergoing transcatheter ViV implantation with Myval device. Results: A total of 11 patients from five institutions were gathered between 2019 and 2022 (age 68 ± 7.8, 63% women). The peak and mean transvalvular gradients were 27 ± 5 mmHg and 14.7 ± 2.3 mmHg, respectively, and the predicted neo-left ventricular outflow tract (neo-LVOT) area was 183.4 ± 56 mm2 (range: 171 to 221 mm2). The procedures were performed via transfemoral access in all cases (through echocardiography-guided transeptal puncture (81.8% transesophageal, 11.2% intracardiac)). Technical success was achieved in all cases, with no significant residual mitral stenosis in any of them (peak 7.2 ± 2.7 and mean gradient 3.4 ± 1.7 mmHg) and no complications during the procedure. There were no data of LVOT obstruction, migration, or paravalvular leak in any case. Mean hospital stay was 3 days, with one major vascular complication and no stroke. At 6-month follow-up, there was one case with suboptimal anticoagulation presenting an increase in the transmitral gradients (mean 15 mmHg) that normalized after optimization of the anticoagulation, but no other relevant events. Conclusions: Transseptal ViV mitral implantation with the balloon-expandable Myval device was feasible and safe avoiding redo surgery in high-risk patients with bioprosthesis degeneration.

Transcatheter Mitral Valve Replacement in High-Surgical Risk Patients: A Single-Center Experience and Outcome

Background

Re-operative mitral valve (MV) replacement is a high-risk procedure, therefore, transcatheter MV replacement (TMVR) is a promising therapeutic option.

Aim

In this study, we aimed to evaluate the feasibility and safety of TMVR in patients with high surgical risk with degenerated mitral bioprostheses (TMViV), failed surgical rings (TMViR), and mitral annular calcification (TMViMAC).

Methods

This is a retrospective cohort study that enrolled patients with high surgical risk who underwent TMVR from February 2017 to September 2020. The TMVR procedure was performed using Edwards SAPIEN-3 valves through the transseptal approach.

Results

Sixty-four patients aged 62.7 ± 16.1 years with an STS score of 9.2 ± 3.7% underwent TMVR [35 (55%) TMViV, 16 (25%) TMViR, and 13 (20%) TMViMAC]. Mitral stenosis was more frequent in TMViV, mitral regurgitation was more frequent in TMViR, and combined mitral stenosis and regurgitation were more frequent in TMViMAC (P < 0.05). The MV gradient was 14.3 ± 5.3 mmHg and the MV area was 1.5±0.6 cm2. The 29 mm valve was frequently used in TMViV and TMViMAC, while the 23 mm valve was frequently used in TMViR (P=0.003 ∗ ). The procedural and fluoroscopy times were 58.7 ± 8.9 and 41.1 ± 8.2 minutes, respectively. Technical success was reported in 62 (98.4%) patients; 1 TMViR patient experienced valve embolization and salvage surgery, and 1 TMViMAC patient experienced slight valve malposition. At 3 months, 2 (3.1%) patients showed valve thrombosis (treated with anticoagulation), and 1 (1.6%) patient developed a paravalvular leak (underwent surgical MV replacement). At 6 months, 3 (4.7%) patients showed valve degeneration (underwent surgical MV replacement). Throughout follow-up, no patient exhibited mortality.

Conclusions

TMVR is a feasible and safe approach in patients with high surgical risk. TMViV and TMViR are reasonable as the first treatment approaches, and TMViMAC seems encouraging.

Clinical outcomes and predictors in patients with previous cardiac surgery undergoing mitral valve transcatheter edge-to-edge repair

BACKGROUND

Mitral-valve transcatheter edge-to-edge repair (MV-TEER) is recommended in patients with severe functional mitral regurgitation (FMR) and in those with degenerative mitral regurgitation (DMR) not eligible to traditional surgery. Patients with a history of previous cardiac surgery are considered at high risk for surgical reintervention, but data are lacking regarding procedural and clinical outcomes.

OBJECTIVE

aim of this study was to assess the efficacy and clinical results of MV-TEER in patients with previous cardiac surgery enrolled in the "multicentre Italian Society of Interventional Cardiology registry of transcatheter treatment of mitral valve regurgitation" (GIOTTO).

METHODS

Patients with previous coronary artery bypass grafting (CABG), surgical aortic valve replacement (AVR), or mitral valve repair (MVR) were included. Those with multiple or combined previous cardiac surgeries were excluded. Clinical follow-up was performed at 30 days, 1 year, and 2 years. The primary endpoint was a composite of death or rehospitalization at 1- and 2-year follow-ups.

RESULTS

A total of 330 patients enrolled in the GIOTTO registry were considered (CABG 77.9%, AVR 14.2%, and MVR 7.9%). Most patients showed FMR (66.9%), moderate reduction of left ventricular (LV) ejection fraction, and signs of LV dilation. Procedural and device successes were 94.8% and 97%. At 1 and 2 years, the composite endpoint occurred are 29.1% and 52.4%, respectively. The composite outcome rates were similar across the three subgroups of previous cardiac surgery (p = 0.928) and between the FMR and DMR subgroups (p = 0.850) at 2 years. In a multivariate analysis, residual mitral regurgitation (rMR) ≥2+ was the main predictor of adverse events at 1 year (hazard ratio: 1.54 [95% confidence interval, CI: 1.00-2.38]; p = 0.050). This association was confirmed at 2 years of Kaplan-Meier analysis (p = 0.001).

CONCLUSIONS

MV-TEER is effective in these patients, regardless of the subtype of previous cardiac surgery and the MR etiology. An rMR ≥2+ is independently associated with adverse outcomes at 1-year follow-up.

Contemporary results of transcatheter mitral valve procedures: bi-centric retrospective analysis

Background

Transcatheter mitral valve-in-valve (TMVIV) or valve-in-ring (TMVIR) replacement offer an alternative therapy for high risk patients. We aimed to highlight the operative and postoperative results of TMVIV and TMVIR procedures.

Results

We included all patients underwent TMVIV and TMVIR procedures between 2017 and 2020 at two heart centers in Germany. We included a total of 36 high risk patients in our study where 12 received TMVIV and 24 received TMVIR. All patients underwent TMVIV or TMVIR with Edwards Sapien XT or S3 transcatheter valves (Edwards Lifesciences). The mean age was 79 (75–83 years old). The median (IQR) preoperative STS score was 9 (7–13)% and EuroSCORE II was 14.5% (12–16). The majority of our patients were operated via transapical approach (n = 26) and the minority via transseptal approach (n = 10). Out of our records, none of our patients required reopening for bleeding or any other surgical complications. None of our patients required reintervention during the 6 months follow-up period. One mortality was recorded on fifth postoperative day due to low cardiac output syndrome (obviously because of LVOT obstruction by the anterior mitral leaflet). The average blood loss was 200 ml in the first 24 h in patients underwent transapical approach. Average operative time was 93 min and all patients were immediately extubated after the procedure in the operating room (even the patient with echocardiographically documented LVOT obstruction who died on the fifth postoperative day). Length of Intensive Care Unit stay was 2 ± 1.2 days and length of hospital stay was 4.1 ± 1.2 days. In the follow up period, echocardiograms showed normal prosthetic valve function with low transvalvular gradients, no LVOT obstruction in TMVIR cases and no evidence of valve migration or thrombosis (except in one patient). Concerning 6 months readmission, it was recorded in 2 patients due to right sided heart failure symptoms due to preexisting high degree of tricuspid valve regurge which did not disappear or even decrease after the operation and the other patient due to gastrointestinal bleeding.

Conclusions

TMVIV and TMVIR offer an efficient, safe and less invasive alternative in high surgical risk patients.

Challenges and Open Issues in Transcatheter Mitral Valve Implantation: Smooth Seas Do Not Make Skillful Sailors

According to the European and American guidelines, surgery represents the treatment of choice for mitral valve (MV) disease. However, a number of patients are deemed unsuitable for surgery due to a prohibitive/high operative risk. In such cases, transcatheter therapies aiming at MV repair have been proven to be a valuable alternative and have been recently introduced in the latest American guidelines on valvular heart disease. Indeed, percutaneous repair techniques, particularly transcatheter edge-to-edge, have gained a broad experience and demonstrated to be safe and effective. However, given the complexity and heterogeneity of MV anatomy and pathology, transcatheter MV implantation (TMVI) has grown as a possible alternative to percutaneous MV repair. Current data about TMVI are still limited and come from different settings: valve-in-native MV, valve-in-valve (ViV), valve-in-ring (ViR), and valve-in-mitral annular calcification. Preliminary data are promising although several open issues still need to be addressed. This paper provides a comprehensive review of the available devices in the different clinical settings, to discuss potentialities, limitations, and future directions for TMVI.

Robotic Mitral Valve Surgery After Prior Sternotomy

Objective

Despite the recent increase in the use of minimally invasive approaches to mitral valve surgery in patients with a prior sternotomy, the outcomes of the robotic approach to mitral valve surgery in this patient population have not been examined.

Methods

We retrospectively reviewed 342 consecutive patients who underwent mitral valve surgery after a prior sternotomy between 2013 and 2020, in which the robotic approach was used in 21 patients (6.1%). We reviewed the clinical details of these 21 patients.

Results

The median age was 71 years [interquartile range 64.00, 74.00 years], and mean Society of Thoracic Surgeons Predicted Risk of Mortality was 4.2% ± 3.8%. The indication for mitral valve surgery was degenerative mitral valve disease in 33.3% (7/21), functional disease in 28.6% (6/21), mixed disease in 4.8% (1/21), rheumatic disease in 9.5% (2/21), and failed repair for degenerative disease in 23.8% (5/21). No cases required conversion from robotic assistance to alternative approaches, there were no intraoperative deaths, and intraoperative transesophageal echocardiogram confirmed complete elimination of mitral regurgitation in 90.5% (19/21) of cases. Thirty-day mortality was 0.0% (0/21), and 1-year mortality was 4.8% (1/21). There were no strokes or wound infections at 30 days, and 14.3% (3/21) of patients received intraoperative blood product transfusions.

Conclusions

The results of this retrospective review suggest that the robotic approach to mitral valve surgery in patients with a prior sternotomy is safe in experienced hands. Although some centers have considered prior sternotomy a relative contraindication to robotic mitral valve surgery, this approach is feasible and can be considered an option for experienced surgeons.

Clinical and Surgical Evaluations of Reoperation After Mechanical Mitral Valve Replacement Due to Different Etiologies

Background:

This study aimed to evaluate the clinical and surgical characteristics of patients who required reoperation after mechanical mitral valve replacement (MVR).

Methods:

We retrospectively identified 204 consecutive patients who underwent reoperation after mechanical MVR between 2009 and 2018. Patients were categorized according the reason for reoperation (perivalvular leakage, thrombus formation, or pannus formation). The patients' medical and surgical records were studied carefully and the rates of in-hospital complications were calculated.

Results:

The mean age was 51±12 years and 44% of the patients were male. The reasons for reoperation were perivalvular leakage (117 patients), thrombus formation (35 patients), and pannus formation (52 patients). The most common positions for perivalvular leakage were at the 6–10 o'clock positions (proportions of ≥25% for each hour position). Most patients had an interval of &gt;10 years between the original MVR and reoperation. The most common reoperation procedure was re-do MVR (157 patients), and 155 of these patients underwent concomitant cardiac procedures. There were 10 in-hospital deaths and 32 patients experienced complications. The 10-year survival rate was 82.2 ± 3.9% in general, and the group of lowest rate was patients with PVL (77.5 ± 5.2%). The independent risk factors were “male” (4.62, 95% CI 1.57–13.58, P = 0.005) and “Hb &lt;9g/dL before redo MV operation” (3.45, 95% CI 1.13–10.49, P = 0.029).

Conclusion:

Perivalvular leakage was the most common reason for reoperation after mechanical MVR, with a low survival rate in long term follow-up relatively.

Five-year outcomes of transcatheter mitral valve implantation and redo surgery for mitral prosthesis degeneration

BACKGROUND

Transcatheter mitral valve replacement (TMVR) has emerged as a feasible alternative to redo surgical mitral valve replacement (SMVR) in patients with degenerated mitral prostheses, with limited comparative data.

METHODS

We compared mid-term outcomes in patients with degenerated mitral valve prostheses treated with TMVR or redo SMVR. The primary endpoint was survival at 5 years of follow-up.

RESULTS

From 2014 to 2020, 215 patients presented with degenerated mitral valve prostheses. Of whom 86 (40%) were treated with TMVR (75[87%] valve-in-valve and 11[13%] valve-in-ring), while 129 patients (60%) underwent SMVR. The TMVR cohort was older (p < 0.0001), more symptomatic (p = 0.0003) and had more chronic lung disease (p = 0.02), worse renal function (p = 0.02) and higher right ventricular systolic pressures (p < 0.0001). Thirty-day mortality was lower with TMVR versus SMVR (2.4% vs. 10.2%, OR4.69 [95% CI 1.25-30.5], p = 0.04) with probability of mortality at 1, 2, and 5 years being 14.7% versus 17.5%, 24.5% versus 20.7%, and 49.9% versus 34.0%, respectively. Mode of prosthesis degeneration, baseline hemodynamics, and valve selection did not appreciably impact outcomes.

CONCLUSIONS

TMVR for degenerated mitral prostheses is associated with better early survival compared to SMVR despite a greater burden of comorbidities. In contrast, 5 year survival rates appear more favorable with SMVR, which may reflect the lower baseline risk of this population. Clinical, hemodynamic, and echocardiographic follow-up support the mid-term durability of TMVR for degenerated mitral prostheses. Further dedicated studies, however, are required to optimize outcomes in this challenging patient cohort and to navigate the choice of approach for each individual patient.

Replacement of a Björk-Shiley tilting disc mitral valve prosthesis 33 years after initial replacement

Björk-Shiley tilting disc prosthesis was the first tilting disc prosthesis to be used worldwide on a large-scale basis. Herein, we report a case of a 67-year-old male presenting with severe prosthetic valvular dysfunction. He had undergone mitral valve replacement with Björk-Shiley valve at some other center in 1987. The surgical challenge was to replace that with an adequately sized prosthesis. To achieve that, we removed all the previously preserved posterior cusp and then reconstructed the sub-valvular apparatus. The patient had a smooth post-operative recovery. This case report highlights the longest reported survival of a Björk-Shiley mitral valve and specific challenges faced during such redo cases.

Transcatheter Mitral Valve-in-Valve Implantation in Pediatric Patients

BACKGROUND

Transcatheter implantation of the Edwards Sapien 3 valve (Edwards Lifesciences, Irvine CA) within the bioprosthetic mitral valve (MV) is an established method of treatment in adults. However, it has not been well studied in the pediatric age group.

METHODS

Transcatheter mitral valve-in-valve implantation was attempted in 4 symptomatic pediatric patients with a dysfunctional MV bioprosthesis implanted at an earlier stage due to severe MV stenosis or regurgitation. We reviewed our experience with MV implantation in this cohort.

RESULTS

The mean age and weight of the patients at the time of the procedure were 11.4 years (range: 10-14 years) and 36 kg (range: 31-44 kg), respectively. The transmitral mean gradient dropped from a mean of 19.75 mm Hg (range: 15-22 mm Hg) to a mean of 1 mm Hg (range: 0-3 mm Hg) after the procedure. The mean fluoroscopy time was 55.25 minutes (range: 40-72 minutes), and the mean hospital length of stay was 4 days (range: 3-7 days). The patients' functional class improved from New York Heart Association class IV to class I during the follow-up period.

CONCLUSIONS

Transcatheter mitral valve-in-valve implantation can be performed safely for dysfunctional bioprosthetic MVs in the pediatric age group with favorable early and midterm outcomes. This procedure offers a viable alternative in patients who have high surgical risk or are deemed unfit for conventional surgery. However, we still recommend a long-term study of this approach in a large cohort, multicentre study.

Comparative differences of mitral valve-in-valve implantation: A new mitral bioprosthesis versus current mosaic and epic valves

OBJECTIVE

Evaluate transcatheter mitral valve replacement (TMVR) valve-in-valve (VIV) outcomes in three different mitral bioprostheses (of comparable measured internal diameters) under stable hemodynamic and surgical conditions by bench, echocardiographic, computerized tomography (CT), and autopsy comparisons pre- and post-valve implantation in a porcine model under matched controlled conditions.

BACKGROUND

Impact of surgical bioprosthesis design on TMVR VIV procedures is unknown.

METHODS

Fifteen similar-sized Yorkshire pigs underwent pre-procedural CT screening. Twelve had consistent anatomic features and underwent implantation of mitral bioprostheses. Four valves from each of three manufacturers were implanted in randomized fashion: 27-mm Epic, 27-mm Mosaic, and 25-mm Mitris, followed by TMVR VIV with 26 Edwards Sapien3. Post-VIV, suprasternal TEE studies were performed to assess hemodynamic function, followed by a gated contrast CT. After euthanasia, animals underwent necropsy for anatomic evaluation.

RESULTS

All 12 animals had successful VIV implantation with no study deaths. The post vivMitris (3.77 ± 0.36)/(2.2 ± 0.25 mmHg) had the lowest peak/mean trans-mitral gradient and the vivEpic the highest (15.5 ± 2.55)/(7.09 ± 1.13 mmHg). All THVs (transcatheter heart valves) had greatest deformation within the center of the THV frame; with the smallest waist opening area in the vivEpic (329 ± 35.8 mm² ) and greatest in the vivMitris (414 ± 33.12 mm² ). Bioprosthetic frames without obvious radiopaque markers resulted in the most ventricular implantation of the THV's anteroseptal frame (Epic: -4.52 ± 0.76 mm), versus the most radiopaque bioprosthesis (Mitris: -1.18 ± 2.95 mm), and higher peak LVOT gradients (Epic: 4.82 ± 1.61 mmHg; Mitris: 2.91 ± 1.47 mmHg).

CONCLUSIONS

The current study demonstrates marked variations in hemodynamics, THV opening area, and anatomic dimensions among measured similarly sized mitral bioprostheses. These data suggest a critical need for understanding the potential impact of variations in bioprosthesis design on TMVR VIV clinical outcomes.

Transapical transcatheter mitral valve implantation in patients with degenerated mitral bioprostheses or failed ring annuloplasty

Background

We sought to evaluate the outcomes of transapical transcatheter mitral valve replacement in patients with degenerated mitral bioprostheses or failed mitral ring annuloplasty and high surgical risk for redo mitral valve procedure.

Methods

Between August 2012 and December 2020, 41 consecutive high-risk patients underwent transcatheter mitral 'valve-in-valve' (TM-ViV, n=25) or 'valve-in-ring' (TM-ViR, n=16) implantation at our institution. All procedures were performed in a hybrid operating theater using the SAPIEN XT/3™ or the DIRECT FLOW MEDICAL™ prostheses. Data was collected prospectively according to MVARC criteria.

Results

The logistic EuroSCORE-I was 42.3%±20.5% (mean ± SD), the Society of Thoracic Surgeons (STS) score was 11.9%±10.8%, and the STS/ACC-score was 7.6%±4.2%. Transcatheter mitral valve implantations were successful in all patients (100%). Early echocardiographic examinations showed no obstruction of the left ventricular outflow tract (LVOT), no paravalvular leakage, and only trace transvalvular leakage in eight patients. There was no operative mortality; thirty-day mortality was 9.8%. Survival was 72% at one year and 63% at three years. At two-year follow-up, transvalvular mean pressure gradients were 4.6±1.4 mmHg.

Conclusions

Transapical transcatheter mitral valve-in-valve or valve-in-ring implantation represents a true minimally invasive alternative to surgical redo procedures, especially in high-risk patients with failed bioprosthetic mitral valves or annuloplasty and favorable anatomy.

Use of transesophageal echocardiography for transcatheter valve-in-valve implantation for patients with prior bioprosthetic surgical aortic, mitral, tricuspid, and pulmonic valves

Valve-in-valve (ViV) transcatheter procedures are the preferred option for redo valve replacement in patients who otherwise would be high risk for surgery. Transesophageal echocardiography (TEE) is an integral imaging modality for both peri-procedural and intra-procedural guidance during transcatheter ViV replacement. When intentional leaflet laceration is needed, such as with the BASILICA (Bioprosthetic or native Aortic Scallop Intentional Laceration to prevent Iatrogenic Coronary Artery obstructions during TAVR) or LAMPOON (Laceration of the Anterior Mitral valve leaflet to Prevent left ventricular Outlet ObstructioN) procedures, TEE is critical to proper guidewire positioning and achieving a successful laceration. In this paper we detail the role of TEE in ViV transcatheter valve replacement in patients with prior surgical aortic, mitral, tricuspid, and pulmonic valves.

Transcatheter valve-in-valve implantation in degenerated surgical aortic and mitral bioprosthesis: Current state and future perspectives

The use of bioprosthetic valves for treating patients with severe valve disease has increased over the last 2 decades, and, as a consequence, a growing number of patients with failing surgical bioprosthesis is expected in the near future. In this setting, valve-in-valve (ViV) transcatheter aortic/mitral valve replacement (TAVR and TMVR) has emerged as an alternative to redo surgery. Despite the increasing experience in ViV procedures, the development of these techniques faces several specific challenges, mainly related to the unique anatomical and physiological characteristics presented in ViV-TAVR/TMVR. Subsequently, various approaches have been proposed to overcome ViV-related complications and pitfalls. A growing body of evidence is currently available concerning early- and long-term clinical outcomes of patients undergoing ViV-TAVR/TMVR. These data should be comprehensively evaluated by the Heart Team in the decision-making process involving patients with failing surgical bioprostheses. In this review, we aimed to delineate the technical challenges and risks associated with ViV-TAVR and ViV-TMVR, provide an updated overview of the main clinical results, and summarize the future perspectives of this evolving field.

Mini-thoracotomy in redo mitral valve surgery: safety and efficacy of a standardized procedure

Background

Re-operative mitral valve surgery is sometimes burdened by a greater technical difficulty and a higher complications rate than the first operation. Minimally invasive cardiac surgery has become routine, and it could significantly reduce the surgical risk in redo surgery. The objective of our retrospective observational study is to assess the results of cardiac reoperations in patients with mitral valve disease approached trough a 5–7 cm right mini-thoracotomy.

Methods

From February 2017 to December 2019, 65 patients underwent re-operative mitral valve surgery in our institution. Cardiopulmonary bypass (CPB) was started by cannulation of the femoral and jugular vein and femoral artery or alternatively right axillary artery. Patients enrolled had a mean age of 66.6±11.5 years. Patients were divided into three groups based on the procedure adopted: external aortic cross-clamp (EAC), EndoAortic balloon occlusion (EABO) and ventricular fibrillation (VF). Major complications were evaluated and compared with a propensity matched population of patients undergoing elective isolated mitral valve surgery via right minithoracotomy (MVS).

Results

The average time between last operation and reoperation was 7.1±3.4 years. Fourteen patients (21%) underwent mitral valve repair and 51 patients (78%) underwent mitral valve replacement; 9 patients (14%) received tricuspid valve surgery. There was no statistically significant difference in CPB time between the groups. Seven patients (11%) had a postoperative renal failure, 5 patients (8%) underwent surgical reopening for bleeding; incidence of post-operative stroke and pace-maker implantation was 3% for both. No deaths were registered during in-hospital stay and at 30-days echocardiographic control all patients respect the criterions of device success according with MVARC. Propensity matched patients of group redo had a longer CPB time (100.8±42.7 versus 72.8±16.7 min, P<0.001) and cross-clamp time (71.9±30.7 versus 59±10.7 min, P<0.001) respect to first operation mitral valve surgery patients.

Conclusions

Minimally invasive mitral valve redo surgery is a safe procedure. Less invasive techniques in redo surgery could minimize morbidity and mortality without prolonging the duration of CPB.

Outcomes of combined aortic and mitral valve replacement with reconstruction of the fibrous skeleton of the heart

OBJECTIVES

The objectives of this study were to examine operative and long-term results of combined aortic and mitral valve replacement when reconstruction of the fibrous skeleton of the heart is needed because of calcification, abscess, previous operations, or patient-prosthesis mismatch.

METHODS

From 1985 to 2020, 182 consecutive patients underwent combined aortic and mitral valve replacement with reconstruction of the intervalvular fibrous skeleton in all cases and also the posterior mitral annulus in 63 patients. Bovine pericardium or Dacron grafts were used for the reconstructions. Median follow-up was 7.5 (interquartile range, 2.1-12.6) years and 98% complete.

RESULTS

Patient mean age was 62 years; 69% had 1 or more previous valve operations, and 92% were functional class III or IV. The indications for reconstruction were extensive calcification of the fibrous skeleton in 34%, abscess in 13%, tissue damage secondary to previous operations in 39%, and patient-prosthesis mismatch of the mitral valve in 13%. Bovine pericardium was used in two-thirds of cases and Dacron grafts in one-third. Operative mortality was 13.2% and postoperative complications were common. Survival at 1, 10, and 20 years was 81.8%, 51.1%, and 23.7%, respectively. Fourteen patients required reoperation and 3 transcatheter interventions. The cumulative probability of reinterventions at 1, 10, and 20 years were 3.3%, 5.8%, and 9.1%, respectively. Most patients experienced symptomatic improvement postoperatively.

CONCLUSIONS

Reconstructions of the fibrous skeleton of the heart are associated with high operative mortality but the long-term results are satisfactory because most patients would not have survived without surgical intervention.

Redo Surgical Mitral Valve Replacement Versus Transcatheter Mitral Valve in Valve From the National Inpatient Sample

Background Redo mitral valve surgery is required in up to one-third of patients and is associated with significant mortality and morbidity. Valve-in-valve transcatheter mitral valve replacement (ViV TMVR) is less invasive and could be considered in those at prohibitive surgical risk. Studies on comparative outcomes of ViV TMVR and redo surgical mitral valve replacement (SMVR) remain limited. Our study aimed to investigate the real-world outcomes of the above procedures using the National Inpatient Sample database. Methods and Results We analyzed National Inpatient Sample data using the International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) from September 2015 to December 2018. A total of 495 and 2250 patients underwent redo ViV TMVR and SMVR, respectively. The patients who underwent ViV TMVR were older (77 versus 68 years, P<0.01). Adjusted mortality was higher in the redo SMVR group compared with the ViV TMVR group (7.6% versus <2.8%, P<0.01). Perioperative complications were higher among patients undergoing redo SMVR including blood transfusions (38% versus 7.6%, P<0.01) and acute kidney injury (36.7% versus 13.9%, P<0.01). Cost of care was higher (USD$57 172 versus USD$52 579, P<0.01), length of stay was longer (10 versus 3 days, P<0.01), and discharge to home was lower (20.3% versus 64.6%, P<0.01) in the SMVR group compared with the ViV TMVR group. Conclusions ViV TMVR is associated with lower mortality, periprocedural morbidity, and resource use compared with patients undergoing redo SMVR. ViV TMVR may be a viable option for some patients with mitral prosthesis dysfunction. Studies evaluating long-term outcomes and durability of ViV TMVR are needed. A patient-centered approach by the heart team, local institutional expertise, and careful preprocedure planning can help decision-making about the choice of intervention for the individual patient.