Mitral valve repair versus replacement in patients with ischaemic mitral regurgitation and depressed ejection fraction: risk factors for early and mid-term mortality†

Restrictive annuloplasty or replacement on reverse remodeling for nonischemic dilated cardiomyopathy

BACKGROUND

For patients with nonischemic dilated cardiomyopathy (NIDCM), the indications for and results of mitral surgery remain controversial. We reviewed a strategy of mitral repair and replacement for clinically relevant secondary mitral regurgitation (MR) in patients with NIDCM.

METHODS

We retrospectively reviewed 65 patients with advanced NIDCM (LVEF < 40%) who underwent mitral surgery. Of them, 47 (72%) underwent mitral annuloplasty and 18 (28%) replacement for secondary MR. The primary endpoint was postoperative reduction in indexed LV end-systolic volume (LVESVI).

RESULTS

At baseline, there was no intergroup difference in LVESVI (123 ± 47 vs. 147 ± 37 ml/m2, P = 0.055), LVEF (27 ± 8% vs. 25 ± 6%, P = 0.41), incidence of severe MR (57% (27/47) vs. 72% (13/18), P = 0.40), or EuroSCORE II score (6.2% vs. 7.6%, P = 0.90). At 6 months, the annuloplasty group reduced LVESVI to a greater degree than the replacement group (P < 0.001), yielding significantly smaller postoperative LVESVI (96 ± 59 vs. 154 ± 61 ml/m2, P < 0.001) and better LVEF (P < 0.001). The rates of moderate/severe recurrent MR were 17% (8/47) and 0%, respectively. Multivariable analysis demonstrated that mitral annuloplasty (OR 6.10, 95% CI 1.14-32.8, P = 0.035) was significantly associated with postoperative LV reverse remodeling. Cumulative survival was not different between the groups (P = 0.26).

CONCLUSIONS

In patients with NIDCM, mitral annuloplasty reduced LV volume to a greater degree than did mitral replacement. These findings may assist with surgical options for secondary MR associated with NIDCM.

The Role of Natriuretic Peptides in Predicting Adverse Outcomes After Cardiac Surgery: An Updated Systematic Review

The increasing global burden of cardiovascular disease, particularly, in the aging population, has led to an increase in high-risk cardiac surgical procedures. The current preoperative risk stratification scores, such as the European System for Cardiac Operative Risk Evaluation and the Society for Thoracic Surgeons score, have limitations in their predictive accuracy and tend to underestimate the mortality risk in higher-risk populations. This systematic review aimed to evaluate the utility of natriuretic peptides, brain natriuretic peptide (BNP) and its precursor prohormone (N-terminal prohormone BNP), as predictive biomarkers for adverse outcomes after cardiac surgery. A comprehensive search strategy was performed, and 63 studies involving 40,667 patients who underwent major cardiac operations were included for data extraction. Preoperative levels of BNP and N-terminal prohormone BNP seemed to be associated with an increased risk of short- and long-term mortality, postoperative heart failure, kidney injury, and length of intensive care unit stay. However, their predictive value for postoperative arrhythmias and myocardial infarction was less established. Our findings suggest that natriuretic peptides may play an important role in risk prediction in patients who underwent cardiac surgery. The addition of these biomarkers to the existing clinical risk stratification strategies may enhance their predictive accuracy. However, this needs to be endorsed by data derived from wide-scale clinical trials.

Clinical Impact of Computational Heart Valve Models

This paper provides a review of engineering applications and computational methods used to analyze the dynamics of heart valve closures in healthy and diseased states. Computational methods are a cost-effective tool that can be used to evaluate the flow parameters of heart valves. Valve repair and replacement have long-term stability and biocompatibility issues, highlighting the need for a more robust method for resolving valvular disease. For example, while fluid-structure interaction analyses are still scarcely utilized to study aortic valves, computational fluid dynamics is used to assess the effect of different aortic valve morphologies on velocity profiles, flow patterns, helicity, wall shear stress, and oscillatory shear index in the thoracic aorta. It has been analyzed that computational flow dynamic analyses can be integrated with other methods to create a superior, more compatible method of understanding risk and compatibility.

Mitral valve repair versus replacement in severe ischemic mitral regurgitation systematic review and meta-analysis

BACKGROUND AND AIM

Ischemic mitral regurgitation (IMR) is a serious consequence of coronary artery disease. The choice of the optimal surgical strategy remains debatable. The aim of the present meta-analysis is to compare the outcomes of mitral valve repair (RPR) versus replacement (RPL) regarding perioperative mortality, overall mortality, reoperation, recurrence of MR, and reverse remodeling after surgery.

METHODS

Electronic searches were performed using the searchable databases of Google Scholar, Pubmed, and Embase, and the search terms mitral valve, IMR, RPR, RPL, and coronary artery bypass grafting. The main outcomes of interest are perioperative mortality, overall mortality, reoperation, recurrence of MR, and reverse remodeling after surgery. Perioperative mortality was defined as death during the surgery or within 30 days after the operation.

RESULTS

There was a trend towards better perioperative survival in the RPR arm. However, the difference fell short of statistical significance [odds ratio (OR) (95% confidence interval [CI]): 0.66 (0.41-1.07), p = 0.09]. Patients submitted to RPR experienced a significantly higher MR recurrence rate when compared with their counterparts submitted to RPL [OR (95% CI): 16.8 (5.07-55.7, p = 0.00001)].

CONCLUSION

There is a trend towards lower perioperative mortality in RPR in comparison to RPL. On the other hand, RPL was associated with significantly lower recurrence rates.

Real-World Outcomes of Revascularization Strategies in Patients With Left Ventricular Dysfunction and Three-Vessel Coronary Disease Stratified by Mitral Regurgitation

Aims: Limited information exists regarding optimal revascularization options for patients with triple-vessel coronary artery disease (TVD), heart failure (HF), and different degrees of mitral regurgitation (MR). Thus, we aimed to compare the effect of percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) surgery in the indicated patients.

Methods and Results: In the real-world prospective study, 1190 patients with multi-vessel disease and decreased left ventricular systolic function but without severe MR, who underwent PCI or CABG, were enrolled and followed-up for 4.7 ± 1.8 years. The primary endpoint was a composite of cardiovascular death and HF hospitalization. Secondary endpoints were the individual components of the primary outcome. Risk of the primary endpoint was higher in the PCI than in the CABG group (HR = 1.38, 95%CI: 1.14–1.67, and P < 0.01), particularly in patients with moderate MR (HR = 1.85, 95%CI: 1.35–2.55, and P < 0.01). In patients with no-mild MR, the risk of the primary endpoint did not differ significantly between PCI and CABG (P = 0.09). Treatment with PCI was associated with an increased risk for cardiovascular death and HF hospitalization in the moderate MR cohort, while PCI was comparable to CABG in the no-mild MR cohort.

Conclusions: In this real-world study, for patients with HF and TVD, CABG was related to lower adverse outcome rates compared to PCI. Assessment of MR can aid in selecting optimal revascularization therapies and in risk stratification.

Repair or Replacement for Secondary Mitral Regurgitation: Results From Polish National Registry

BACKGROUND

The optimal surgical strategy (repair vs replacement) for patients with secondary mitral (MV) regurgitation is questionable.

METHODS

Patients who underwent MV repair or replacement for functional or ischemic mitral regurgitation between 2006 and 2017 were identified in Polish National Registry of Cardiac Surgery Procedures. Patients, who underwent additional procedures other than coronary artery bypass grafting or tricuspid valve surgery, as well as redo or emergency cases, were excluded. The long-term survival was verified based on National Health Fund registry. The survival was compared between MV repair and replacement both in the whole cohort and after propensity score matching. The Cox regression was used to seek for independent predictors of survival.

RESULTS

Of 7633 identified patients, 1793 (23%) underwent MV replacement and 5840 (77%) underwent MV repair. Coronary artery bypass surgery was performed together with MV repair in 3992 (69%) patients and together with MV replacement in 915 (52%) patients (P < .001). Tricuspid valve surgery was added to 1393 (24%) MV repairs and to 561 (32%) MV replacements (P < .001). The crude actuarial 5-year survival was 71% (95% confidence interval [CI], 70%-72%) in the repair group and 66% (95% CI, 63%-68%) in the replacement group (P < .001). MV replacement was an independent predictor of mortality (hazard ratio, 1.32; 95% CI, 1.17-1.49) (P < .001) in Cox regression modeling. In the propensity-matched cohort (1105 pairs), the long-term mortality was also significantly higher in the replacement group (hazard ratio, 1.24; 95% CI, 1.06-1.45; P = .008).

CONCLUSIONS

Repair of secondary mitral regurgitation has an associated survival benefit compared with MV replacement.

Multicenter experience: early outcome of mitral valve repair in patients with ischemic mitral regurgitation

BACKGROUND

Ischemic mitral regurgitation is associated with poor outcomes. The optimal surgical strategy for management of ischemic mitral regurgitation is still debated. The objective of this study was to evaluate the early mortality and morbidity of mitral valve repair in patients with ischemic mitral regurgitation undergoing coronary artery bypass grafting.

METHODS

We performed a retrospective, observational, cohort study on prospectively collected data on 136 consecutive coronary artery bypass graft patients with ischemic mitral regurgitation undergoing mitral valve repair between January 2016 and January 2020. Perioperative echocardiogram findings, operative procedures, and outcomes were analyzed.

RESULTS

The overall mortality rate was 4.4%. Mitral valve repair with a low ejection fraction had a 4-fold increase in the risk of death compared to mitral valve repair with preserved ejection fraction > 30%. However, after adjusting for preoperative risk factors, the number of grafts was not an independent risk factor for mortality (odds ratio = 0.18, 95% confidence interval: 0.03-2.81, p = 0.84). Multivariable analysis showed that preoperative ejection fraction (odds ratio = 1.14, 95% confidence interval: 0.82-4.86, p < 0.01), preoperative left ventricular end-systolic dimension (odds ratio = 1.03, 95% confidence interval: 0.65-3.51, p < 0.01) and preoperative left ventricular end-diastolic dimension (odds ratio = 0.99, 95% confidence interval: 0.64-3.28, p = 0.04) were independent risk factors for mortality.

CONCLUSIONS

Mitral valve repair can be performed safely concomitantly with coronary artery bypass grafting in patients with moderate, moderately severe, and severe ischemic mitral regurgitation.

Interrelationship Between Kidney Function and Percutaneous Mitral Valve Interventions: A Comprehensive Review

Percutaneous mitral valve repair is emerging as a reasonable alternative especially in those with an unfavorable surgical risk profile in the repair of mitral regurgitation. At this time, our understanding of the effects of underlying renal dysfunction on outcomes with percutaneous mitral valve repair and the effects of this procedure itself on renal function is evolving, as more data emerges in this field. The current evidence suggests that the correction of mitral regurgitation via percutaneous mitral valve repair is associated with some degree of improvement in cardiac function, hemodynamics and renal function. The improvement in renal function was more significant for those with greater renal dysfunction at baseline. The presence of Chronic Kidney Disease (CKD) in turn has been associated with poor long-term outcomes including increased mortality and hospitalization among patients who undergo percutaneous mitral valve repair. This was true regardless of the degree of improvement in GFR post repair advanced CKD. The adverse impact of CKD on long-term outcomes was consistent across all studies and was more prominent in those with GFR<30 mL/min/1.73 m². It is clear that from these contrasting evidences of improved renal function post mitral valve repair but poor long-term outcomes including increased mortality in patients with CKD, that proper patient selection for percutaneous mitral valve repair is key. There is a need to have better-standardized criteria for patients who should qualify to have percutaneous mitral valve replacement with Mitraclip. In this new era of percutaneous mitral valve repair, much work needs to be done to optimize long-term patient outcomes.

Repair or replacement for severe ischemic mitral regurgitation: A meta-analysis

BACKGROUND

The best surgical option for severe ischemic mitral regurgitation (IMR) is still controversial. The aim of this study was to perform a meta-analysis to compare the clinical outcomes of mitral valve repair (MVP) with replacement (MVR).

METHODS

A literature search was conducted in PubMed, Embase, and Medline using the terms "ischemic mitral regurgitation" and "repair or annuloplasty or reconstruction" and "replacement" in the title/abstract field. The primary outcomes of interest were perioperative mortality and long-term survival. Secondary outcomes were mitral regurgitation (MR) recurrence and reoperation.

RESULTS

Of 276 studies, 13 studies met the inclusion and exclusion criteria. A total of 1993 patients were included in these studies, consisting of 1259 (63%) repair cases, and 734 (37%) replacement cases. Perioperative mortality was lower with MVP compared with MVR [OR 0.61; (95% CI, 0.43-0.87; P < .05)]. There was no difference with respect to long-term survival [HR 0.75; (95% CI, 0.52-1.09; P = .14)] and reoperation [OR 0.77; (95% CI, 0.38-1.57; P = .47)]. MVP is associated with a higher recurrence of MR [OR = 4.09; (95% CI, 1.82-9.19; P < .001)].

CONCLUSION

MVP is associated with a lower perioperative mortality but a higher recurrence of MR compared with MVR for severe IMR. No differences were found with respect to long-term survival and reoperation.

Surgical Treatment of Ischemic Mitral Regurgitation: Valve Repair Versus Replacement

PURPOSE OF REVIEW

Ischemic mitral regurgitation (MR), which occurs in about 20-30% patients with a prior myocardial infarction, is associated with worsening heart failure and an increase in cardiovascular mortality. It should be treated surgically if certain hemodynamic severity criteria are met and in patients who continue to experience symptoms of heart failure despite optimal medical therapy. However, current guidelines do not suggest which of the available approaches to mitral valve surgery-mitral valve (MV) repair or replacement (MVR) is superior for this indication. While MV repair is reported to confer improved survival, MVR may provide higher rates of freedom from recurrent MR. This article attempts to provide the reader with a comprehensive review and comparison of current techniques of mitral valve surgery in patients with severe ischemic MR.

RECENT FINDINGS

The first randomized trial to compare MV repair versus MVR in patients with severe ischemic MR, the Cardiothoracic Surgical Trials Network (CTSN) trial, was recently concluded and reported no significant difference in the primary outcome of left ventricular end systolic volume index between the two approaches at either 1- or 2-year follow-ups. Data comparing approaches of MV repair and MVR for ischemic MR is largely limited to small, non-randomized retrospective trials. The only randomized trial data to examine this issue suggested no difference in mortality with either MVR or MV repair; however, MVR was shown to be consistently associated with higher rates of MR recurrence. Certain echocardiographic features have been reported to predict poor outcomes with MVR and may help refine the selection of the surgical approach in the individual patient.

Repair or replace ischemic mitral regurgitation during coronary artery bypass grafting? A meta-analysis

Background

No agreement has been reached for the best surgical treatment for patients with chronic ischemic mitral regurgitation (IMR) undergoing coronary artery bypass grafting (CABG). Our objective was to meta-analyze the clinical outcomes of repair and replacement.

Methods

A computerized search was performed using Pubmed, Embase, Ovid medline and Cochrane Library. The search terms “ischemic or ischaemic” and “mitral valve” and “repair or replacement or annuloplasty” and “coronary artery bypass grafting” were entered as MeSH terms and keywords. The primary outcomes were operative mortality and late mortality. Secondary outcomes were 2+ or greater recurrence of mitral regurgitation and reoperation rate.

Results

Eleven studies were eligible for the final meta-analysis. These studies included a total of 1750 patients, 60.4 % of whom received mitral valve repair. All patients underwent concomitant coronary artery bypass graft. No differences were found in operative mortality (summary odds ratio [OR] 0.65; 95 % confidence interval [CI] 0.43-1.00; p = 0.05), late mortality (summary hazard ratio [HR] 0.87; 95 % confidence interval [CI] 0.67-1.14; p = 0.31) and reoperation (summary odds ratio [OR] 1.47; 95 % confidence interval [CI] 0.90-2.38; p = 0.12). Regurgitation recurrence was lower in the replacement group (summary odds ratio [OR] 5.41; 95 % confidence interval [CI] 3.12-9.38; p < 0.001).

Conclusion

In patients with chronic ischemic mitral regurgitation during CABG, mitral valve replacement is associated with lower recurrence of regurgitation. No differences were found regarding survival and reoperation rates.

Is valve repair preferable to valve replacement in ischaemic mitral regurgitation? A systematic review and meta-analysis

Ischaemic mitral regurgitation (MR) is associated with poor survival. The favoured surgical option remains debatable. Our aim was to perform a meta-analysis to compare the outcomes of mitral valve repair (MVRp) with replacement (MVR). A literature search was conducted in PubMed, Medline and Ovid using the terms 'ischaemic mitral regurgitation', 'repair' and 'replacement'. The primary outcome measure was 30-day survival. The secondary outcome measures were MR recurrence and reoperation. Out of 310 articles, 18 fulfilled the inclusion criteria. A total of 3978 patients were included: 2563 (64%) MVRp cases and 1415 (36%) MVR cases. Operative techniques included annuloplasty for MVRp and subvalvular apparatus-sparing MVR techniques. Thirty-day mortality was lower after MVRp compared with MVR [OR 0.42; (95% CI 0.33-0.54; P = 0.0001)]. There was no difference in long-term survival ranging 1-5 years (HR 0.85, 95% CI 0.65-1.12). Recurrence of MR was significantly higher in the MVRp group (OR 4.26, 95% CI 2.52-7.22), as was the rate of reoperation (OR 2.03, 95% CI 1.49-2.77). Although MVR for ischaemic MR has a higher 30-day mortality rate compared with MVRp, MVRp is associated with the higher rate of MR recurrence and the need for reoperation. MVR remains an attractive option for ischaemic MR.

A meta-analysis of mitral valve repair versus replacement for ischemic mitral regurgitation

BACKGROUND

The development of ischemic mitral regurgitation (IMR) portends a poor prognosis and is associated with adverse long-term outcomes. Although both mitral valve repair (MVr) and mitral valve replacement (MVR) have been performed in the surgical management of IMR, there remains uncertainty regarding the optimal approach. The aim of the present study was to meta-analyze these two procedures, with mortality as the primary endpoint.

METHODS

Seven databases were systematically searched for studies reporting peri-operative or late mortality following MVr and MVR for IMR. Data were independently extracted by two reviewers and meta-analyzed according to pre-defined study selection criteria and clinical endpoints.

RESULTS

Overall, 22 observational studies (n=3,815 patients) and one randomized controlled trial (n=251) were included. Meta-analysis demonstrated significantly reduced peri-operative mortality [relative risk (RR) 0.61; 95% confidence intervals (CI), 0.47-0.77; I(2)=0%; P<0.001] and late mortality (RR, 0.78; 95% CI, 0.67-0.92; I(2)=0%; P=0.002) following MVr. This finding was more pronounced in studies with longer follow-up beyond 3 years. At latest follow-up, recurrence of at least moderate mitral regurgitation (MR) was higher following MVr (RR, 5.21; 95% CI, 2.66-10.22; I(2)=46%; P<0.001) but the incidence of mitral valve re-operations were similar.

CONCLUSIONS

In the present meta-analysis, MVr was associated with reduced peri-operative and late mortality compared to MVR, despite an increased recurrence of at least moderate MR at follow-up. However, these findings must be considered within the context of the differing patient characteristics that may affect allocation to MVr or MVR. Larger prospective studies are warranted to further compare long-term survival and freedom from re-intervention.