Contribution of ischemic mitral regurgitation to congestive heart failure after myocardial infarction

Two-dimensional transthoracic measure of mitral annulus in mitral valve prolapse and moderate to severe regurgitation: a method comparison analysis with three-dimensional transesophageal echocardiography

BACKGROUND

Mitral annulus (MA) area is derived during transthoracic echocardiography (TTE) assuming of a circular shape using the MA diameter from the apical 4 chamber (A4c) view. Since the MA is not a circular structure, we hypothesized that an elliptical model using parasternal long-axis (PLAX) and apical 2 chamber (A2c) view measured MA diameters would have better agreement with 3-dimensional transesophageal echocardiography (3D TEE) measured MA in degenerative mitral valve disease (DMVD).

METHODS

Seventy-six patients with moderate-to-severe DMVD had 2D TTE and 3D TEE performed. MA area was measured retrospectively using semi-automatic modeling of 3D data (3D TEEsa) and considered as the reference method. MA diameters were measured using different 2D TTE views. MA area was calculated using assumptions of a circular or an elliptical shape. 2D TTE derived and 3D TEEsa. MA areas were compared using linear regression and Bland-Altman analysis.

RESULTS

The median MA area measured at 3D TEEsa was 1,386 (1,293-1,673) mm2. With 2D TTE, the circular model using A4c view diameter resulted in a small systematic underestimation of MA area (6%), while the elliptical model using PLAX and A2c diameters resulted in 25% systematic underestimation. The standard deviations of the distributions of inter-method differences were wide for all 2D TTE methods (265-289 mm2) when compared to 3D TEEsa, indicating imprecision.

CONCLUSIONS

When compared with 3D TEEsa modeling of the MA as the reference, the assumption of a circular shape using A4c TTE view diameter was the method with the least systematic error to assess MA area in DMVD and moderate to severe regurgitation.

Efficacy of mitral valve repair in combination with coronary revascularization for moderate ischaemic mitral regurgitation: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

The efficacy of mitral valve repair (MVR) in combination with coronary artery bypass grafting (CABG) for moderate ischaemic mitral regurgitation (IMR) remains unclear. To evaluate whether MVR + CABG is superior to CABG alone, the authors conducted a systematic review and meta-analysis of existing randomized controlled trials (RCTs).

METHODS

The authors searched PubMed, Web of Science, and the Cochrane Central Register of Controlled Trials for eligible RCTs from the date of their inception to October 2023. The primary outcomes were operative (in-hospital or within 30 days) and long-term (≥ 1 year) mortality. The secondary outcomes were postoperative stroke, worsening renal function (WRF), and reoperation for bleeding or tamponade. The authors performed random-effects meta-analyses and reported the results as risk ratios (RRs) with 95% CIs.

RESULTS

Six RCTs were eligible for inclusion. Compared with CABG alone, MVR + CABG did not increase the risk of operative mortality (RR, 1.244; 95% CI, 0.514-3.014); however, it was also not associated with a lower risk of long-term mortality (RR, 0.676; 95% CI, 0.417-1.097). Meanwhile, there was no difference between the two groups in terms of postoperative stroke (RR, 2.425; 95% CI, 0.743-7.915), WRF (RR, 1.257; 95% CI, 0.533-2.964), and reoperation for bleeding or tamponade (RR, 1.667; 95% CI, 0.527-5.270).

CONCLUSIONS

The findings of this meta-analysis suggest that MVR + CABG fails to improve the clinical outcomes of patients with moderate IMR compared to CABG alone.

Postmyocardial Infarction Ventricular Aneurysm: JACC Focus Seminar 5/5

Ventricular aneurysm represents a rare complication of transmural acute myocardial infarction, although other cardiac, congenital, or metabolic diseases may also predispose to such condition. Ventricular expansion includes all the cardiac layers, usually with a large segment involved. Adverse events include recurrent angina, reduced ventricular stroke volume with congestive heart failure, mitral regurgitation, thromboembolism, and ventricular arrhythmias. Multimodality imaging is paramount to provide comprehensive assessment, allowing for appropriate therapeutic decision-making. When indicated, surgical intervention remains the gold standard, although additional therapy (heart failure, anticoagulation, and advanced antiarrhythmic treatment) might be required. However, the STICH (Surgical Treatment for Ischemic Heart Failure) trial did not show any advantage from adding surgical ventricular reconstruction to coronary artery bypass surgery in terms of survival, rehospitalization or symptoms, compared with revascularization alone. Finally, implantable cardiac defibrillator may reduce the risk of fatal arrhythmias.

Prevalence, clinical characteristics and outcomes of heart failure patients with or without isolated or combined mitral and tricuspid regurgitation: An analysis from the ESC-HFA Heart Failure Long-Term Registry

AIM

Mitral regurgitation (MR) and tricuspid regurgitation (TR) are common in patients with heart failure (HF). The aim of this study was to investigate prevalence, clinical characteristics and outcomes of patients with or without isolated or combined MR and TR across the entire HF spectrum.

METHODS AND RESULTS

The ESC-HFA EORP HF Long-Term Registry is a prospective, multicentre, observational study including patients with HF and 1-year follow-up data. Outpatients without aortic valve disease were included and stratified according to isolated or combined moderate/severe MR and TR. Among 11 298 patients, 7541 (67%) had no MR/TR, 1931 (17%) isolated MR, 616 (5.5%) isolated TR and 1210 (11%) combined MR/TR. Baseline characteristics were differently distributed across MR/TR categories. Compared to HF with reduced ejection fraction, HF with mildly reduced ejection fraction was associated with a lower risk of isolated MR (odds ratio [OR] 0.69; 95% confidence interval [CI] 0.60-0.80), and distinctly lower risk of combined MR/TR (OR 0.51; 95% CI 0.41-0.62). HF with preserved ejection fraction (HFpEF) was associated with a distinctly lower risk of isolated MR (OR 0.42; 95% CI 0.36-0.49), and combined MR/TR (OR 0.59; 95% 0.50-0.70), but a distinctly increased risk of isolated TR (OR 1.94; 95% CI 1.61-2.33). All-cause death, cardiovascular death, HF hospitalization and combined outcomes occurred more frequently in combined MR/TR, isolated TR and isolated MR versus no MR/TR. The highest incident rates were observed in isolated TR and combined MR/TR.

CONCLUSION

In a large cohort of outpatients with HF, prevalence of isolated and combined MR and TR was relatively high. Isolated TR was driven by HFpEF and was burdened by an unexpectedly poor outcome.

Outcome of Surgery for Ischemic Mitral Regurgitation Depends on the Type and Timing of the Coronary Revascularization

OBJECTIVE

Long-term outcomes of mitral valve (MV) repair versus MV replacement for ischemic mitral regurgitation (IMR) in patients undergoing either prior (PCR) or concomitant coronary revascularization (CCR) by surgery (CABG) or intervention (PCI) are uncertain.

METHODS AND RESULTS

Of 446 patients receiving MV surgery for IMR between July 2006 and December 2010, 125 patients-87 CCR (69.1%) and 38 PCR (30.9%)-were eligible for inclusion in the study. Survival was higher in CCR versus PCR at long-term follow-up (78.83% vs. 57.9%, p = 0.016). The incidence of MACCE was lower in the CCR compared to PCR at both hospital discharge (34.11% vs. 63.57%, p = 0.003) and at follow-up (34.11% vs. 65.79%, p = 0.0008). Patients receiving CABG or CABG with PCI in PCR had higher mortality risks after MV surgery than CCR patients (X2 = 6.029, p = 0.014 and X2 = 6.466, p = 0.011, respectively). Whereas in the PCR group, MV repair and MV replacement achieved similar survival probability (X2 = 1.551, p = 0.213), MV repair in the CCR group led to improved survival compared to MV replacement (X2 = 3.921, p = 0.048). In MV replacement, LAD-CABG improved survival compared to LAD-PCI (U = 15,000.00, Z = -2.373 p = 0.018), and a substantial impact of arterial IMA-LAD grafting was revealed in the Cox-regression analysis (HR 0.334, CI: 0.113-0.989, p = 0.048) as opposed to venous-LAD grafting (HR 0.588, CI: 0.166-2.078, p = 0.410).

CONCLUSION

Early treatment of IMR concomitant to coronary revascularization enhances long-term survival compared to delayed MV surgery after PCR. MV repair is not superior to MV replacement when performed late after coronary revascularization; however, MV repair leads to better survival than MV replacement when performed concomitantly with CABG with arterial LAD revascularization.

Comparison of Coronary Artery Bypass Grafting Combined With Mitral Valve Repair Versus Coronary Artery Bypass Grafting Alone in Patients With Moderate Ischemic Mitral Regurgitation: A Meta-Analysis

The aim of this meta-analysis was to compare clinical outcomes between those who underwent coronary artery bypass grafting (CABG) alone and CABG with mitral valve repair (MVR) in patients with moderate ischemic mitral regurgitation. The present study was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Two authors performed a comprehensive search of international databases, including PubMed, EMBASE, and the Cochrane Library, for relevant studies published from inception to March 1, 2023. The search was performed again before the submission of the manuscript on March 20, 2023. Primary outcomes assessed in the present meta-analysis included early mortality and long-term mortality. Secondary outcomes assessed in the present meta-analysis included change in New York Heart Association (NYHA) score from baseline, change in ejection fraction (EF) from baseline (%), and major cardiovascular events (MACE). A total of 13 studies were included in the present meta-analysis. Out of 13 included studies, four were randomized control trials (RCTs) and nine were retrospective cohort studies. The pooled analysis showed that early mortality was significantly lower in patients in the CABG group compared to the CABG+MVR group (risk ratio [RR]: 0.47, 95% confidence interval [CI]: 0.31, 0.70). Long-term mortality was also lower in patients who underwent CABG compared to patients in the CABG+MVR group. However, the difference was statistically insignificant (RR: 0.88, 95% CI: 0.77, 1.02). No significant differences were reported in the EF score between patients who underwent CABG and patients who underwent CABG plus MVR (mean difference [MD]: 0.40, 95% CI: -1.90, 2.69). NYHA score was significantly lower in patients in the CABG+repair group compared to the CABG alone group (MD: 0.39, 95% CI: 0.06, 0.72). In conclusion, our meta-analysis suggests that concomitant MVR during CABG may not improve clinical outcomes in patients with moderate ischemic mitral regurgitation. Further clinical trials are needed to investigate this intervention in more detail.

Impact of assuming a circular orifice on flow error through elliptical regurgitant orifices: computational fluid dynamics and in vitro analysis of proximal flow convergence

Grounded in hydrodynamic theory, proximal isovelocity surface area (PISA) is a simplistic and practical technique widely used to quantify valvular regurgitation flow. PISA provides a relatively reasonable, though slightly underestimated flow rate for circular orifices. However, for elliptical orifices frequently seen in functional mitral regurgitation, PISA underestimates the flow rate. Based on data obtained with computational fluid dynamics (CFD) and in vitro experiments using systematically varied orifice parameters, we hypothesized that flow rate underestimation for elliptical orifices by PISA is predictable and within a clinically acceptable range. We performed 45 CFD simulations with varying orifice areas 0.1, 0.3 and 0.5 cm², orifice aspect ratios 1:1, 2:1, 3:1, 5:1, and 10:1, and peak velocities (V_max) 400, 500 and 600 cm/s. The ratio of computed effective regurgitant orifice area to true effective area (EROA_C/EROA) against the ratio of aliasing velocity to peak velocity (V_A/V_max) was analyzed for orifice shape impact. Validation was conducted with in vitro imaging in round and 3:1 elliptical orifices. Plotting EROA_C/EROA against V_A/V_max revealed marginal flow underestimation with 2:1 and 3:1 elliptical axis ratios against a circular orifice (< 10% for 8% V_A/V_max), rising to ≤ 35% for 10:1 ratio. In vitro modeling confirmed CFD findings; there was a 8.3% elliptical EROA underestimation compared to the circular orifice estimate. PISA quantification for regurgitant flow through elliptical orifices produces predictable, but generally small, underestimation deemed clinically acceptable for most regurgitant orifices.

Contemporary Management of Ischemic Mitral Regurgitation at Coronary Artery Bypass Grafting

BACKGROUND

Recent guidelines for the treatment of moderate or severe ischemic mitral regurgitation (IMR) in patients undergoing coronary artery bypass grafting (CABG) have changed. This study assessed the real-world impact of changing guidelines on the management of IMR during CABG over time. We hypothesized that the utilization of mitral valve repair for IMR would decrease over time, whereas mitral valve replacement for severe IMR would increase.

METHODS

Patients undergoing CABG in a statewide collaborative database (2011-2020) were stratified by severity of IMR. Trends in mitral valve repair or replacement were evaluated. To account for differences of the patients, propensity score-matched analyses were used to compare patients with and without mitral intervention.

RESULTS

A total of 11,676 patients met inclusion criteria, including 1355 (11.6%) with moderate IMR and 390 (3.3%) with severe IMR. The proportion of patients undergoing mitral intervention for moderate IMR decreased over time (2011, 17.7%; 2020, 7.5%; P_trend = .001), whereas mitral replacement for severe IMR remained stable (2011, 11.1%; 2020, 13.3%; P_trend = .14). Major morbidity was higher for patients with moderate IMR who underwent mitral intervention (29.1% vs 19.9%; P = .005). In a propensity analysis of 249 well-matched pairs, there was no difference in major morbidity (29.3% with mitral intervention vs 23.7% without; P = .16) or operative mortality (1.2% vs 2.4%; P = .5).

CONCLUSIONS

Consistent with recent guideline updates, patients with moderate IMR were less likely to undergo mitral repair. However, the rate of replacement for severe IMR did not change. Mitral intervention during CABG did not increase operative mortality or morbidity.

Impact of secondary mitral regurgitation on survival in atrial and ventricular dysfunction

BACKGROUND

Natural history of atrial and ventricular secondary mitral regurgitation (SMR) is poorly understood. We compared the impact of the degree of SMR on survival between atrial and ventricular dysfunction.

METHODS

We conducted a retrospective cohort study of patients who underwent echocardiography in a healthcare network between 2013-2018. We compared the survival of patients with atrial and ventricular dysfunction, using propensity scores developed from differences in patient demographics and comorbidities within SMR severity strata (none, mild, moderate or severe). We fitted Cox proportional hazards models to estimate the risk-adjusted hazards of death across different severities of SMR between patients with atrial and ventricular dysfunction.

RESULTS

Of 11,987 patients included (median age 69 years [IQR 58-80]; 46% women), 6,254 (52%) had isolated atrial dysfunction, and 5,733 (48%) had ventricular dysfunction. 3,522 patients were matched from each arm using coarsened exact matching. Hazard of death in atrial dysfunction without SMR was comparable to ventricular dysfunction without SMR (HR 1.1, 95% CI 0.9-1.3). Using ventricular dysfunction without SMR as reference, hazards of death remained higher in ventricular dysfunction than in atrial dysfunction across increasing severities of SMR: mild SMR (HR 2.1, 95% CI 1.8-2.4 in ventricular dysfunction versus HR 1.7, 95%CI 1.5-2.0 in atrial dysfunction) and moderate/severe SMR (HR 2.8, 95%CI 2.4-3.4 versus HR 2.4, 95%CI 2.0-2.9).

CONCLUSIONS

SMR across all severities were associated with better survival in atrial dysfunction than in ventricular dysfunction, though the magnitude of the diminishing survival were similar between atrial and ventricular dysfunction in increasing severity of SMRs.

Temporal trend and potential impact of angiotensin receptor neprilysin inhibitors on transcatheter edge-to-edge mitral valve repair

INTRODUCTION AND OBJECTIVES

Transcatheter edge-to-edge repair (TEER) should be considered in patients with heart failure and secondary mitral regurgitation (MR). Angiotensin receptor-neprilysin inhibitors (ARNIs) have been demonstrated to improve prognosis in heart failure. We aimed to evaluate the impact ARNIs on patient selection and outcomes.

METHODS

The population of the Spanish TEER prospective registry (March 2012 to January 2021) was divided into 2 groups: a) TEER before the ARNI era (n=450) and b) TEER after the recommendation of ARNIs by European Guidelines (n=639), with further analysis according to intake (n=52) or not (n=587) of ARNIs.

RESULTS

A total of 1089 consecutive patients underwent TEER for secondary MR. In the ARNI era, there was a reduction in left ventricle dilation (82mL vs 100mL, P=.025), and better function (35% vs 38%, P=.011). At 2 years of follow-up, mortality (10.6% vs 17.3%, P <.001) and heart failure readmissions (16.6% vs 27.8%, P <.001) were lower in the ARNI era, but not recurrent MR. In the ARNI era, 1- and 2-year mortality were similar irrespective of ARNI intake but patients on ARNIs had a lower risk of readmission+mortality at 2 years (OR, 0.369; 95%CI, 0.137-0.992; P=.048), better NYHA class, and lower recurrence of MR III-IV (1.9% vs 14.3%, P=.011).

CONCLUSIONS

Better patient selection for TEER has been achieved in the last few years with a parallel improvement in outcomes. The use of ARNIs was associated with a significant reduction in overall events, better NYHA class, and lower MR recurrence.

An Integrative, Multiparametric Approach to Mitral Regurgitation Evaluation

Echocardiography is the first-line modality for assessing mitral regurgitation (MR). In addition to evaluation of the MR jet characteristics, echocardiography can provide quantitative parameters of MR severity. This case series illustrates the importance of integrating multiple parameters in the evaluation of MR and the role of multimodality imaging. (Level of Difficulty: Advanced.)

Wnt Site Signaling Inhibitor Secreted Frizzled‐Related Protein 3 Protects Mitral Valve Endothelium From Myocardial Infarction–Induced Endothelial‐to‐Mesenchymal Transition

Background

The onset and mechanisms of endothelial‐to‐mesenchymal transition (EndMT) in mitral valve (MV) leaflets following myocardial infarction (MI) are unknown, yet these events are closely linked to stiffening of leaflets and development of ischemic mitral regurgitation. We investigated whether circulating molecules present in plasma within days after MI incite EndMT in MV leaflets.

Methods and Results

We examined the onset of EndMT in MV leaflets from 9 sheep with inferior MI, 8 with sham surgery, and 6 naïve controls. Ovine MVs 8 to 10 days after inferior MI displayed EndMT, shown by increased vascular endothelial cadherin/α‐smooth muscle actin–positive cells. The effect of plasma on EndMT in MV endothelial cells (VECs) was assessed by quantitative polymerase chain reaction, migration assays, and immunofluorescence. In vitro, post‐MI plasma induced EndMT marker expression and enhanced migration of mitral VECs; sham plasma did not. Analysis of sham versus post‐MI plasma revealed a significant drop in the Wnt signaling antagonist sFRP3 (secreted frizzled‐related protein 3) in post‐MI plasma. Addition of recombinant sFRP3 to post‐MI plasma reversed its EndMT‐inducing effect on mitral VECs. RNA‐sequencing analysis of mitral VECs exposed to post‐MI plasma showed upregulated FOXM1 (forkhead box M1). Blocking FOXM1 reduced EndMT transcripts in mitral VECs treated with post‐MI plasma. Finally, FOXM1 induced by post‐MI plasma was downregulated by sFRP3.

Conclusions

Reduced sFRP3 in post‐MI plasma facilitates EndMT in mitral VECs by increasing the transcription factor FOXM1. Restoring sFRP3 levels or inhibiting FOXM1 soon after MI may provide a novel strategy to modulate EndMT in the MV to prevent ischemic mitral regurgitation and heart failure.

Effect of Mitral Regurgitation on Left Ventricular Deformation in Myocardial Infarction Patients: Evaluation by Cardiac Magnetic Resonance Imaging

BACKGROUND

Mitral regurgitation (MR) is a comorbidity of myocardial infarction (MI), which may promote the incidence of adverse cardiovascular clinical events. However, it is not yet completely understood how MR in MI patients is associated with impaired myocardial deformation.

PURPOSE

To determine the damaging myocardium effects of MR in MI patients in terms of the global peak strain (PS) and left ventricular (LV) function, and evaluate the independent risk factors impacting LV deformation after MI.

STUDY TYPE

Retrospective.

POPULATION

One hundred eighty-six MI patients (17.7% female) and 84 normal control subjects (27.4% female).

FIELD STRENGTH/SEQUENCE

3.0T; late gadolinium enhancement sequence, balanced steady-state free precession.

ASSESSMENT

LV function and LV global PS (global radial peak strain [GRPS]; global circumferential peak strain [GCPS]; and global longitudinal peak strain [GLPS]) were compared among normal controls, MI without MR (MR-) and MI with MR (MR+, mild, moderate, severe) patients.

STATISTICAL TESTS

One-way analysis of variance (ANOVA) test, Mann-Whitney U test, Kruskal-Wallis test, and multiple linear regressions were used. A P value <0.05 indicated statistically significant difference (two-tailed).

RESULTS

The MI (MR+) patients showed significantly lower LV global PS than both MI (MR-) and control groups in three directions (GRPS 16.66 ± 7.43%; GCPS -11.27 ± 4.27%; GLPS -7.75 ± 3.44%), and significantly higher LV end-systolic (128.85 [87.91, 188.01] mL) and end-diastolic volumes (210.29 [164.07, 264.00] mL) and significantly lower LV ejection fraction (38.23 ± 13.02%). Multiple regression analysis demonstrated that MR was independently associated with LV GCPS (β = -0.268) and GLPS (β = -0.320). LV infarct size was an independent indicator of LV GRPS (β = -0.215) and GCPS (β = -0.222). LV end-diastolic volume was an independent indicator of LV GRPS (β = -0.518), GCPS (β = -0.503), and GLPS (β = -0.331).

DATA CONCLUSION

MR may further exacerbate the reduction of LV global peak strains and function. The MR, infarct size, and LV end-diastolic volume can be used as independent association indicators for LV global PS in MI (MR+) patients.

LEVEL OF EVIDENCE

4 Technical Efficacy Stage: 2 TOC Category: Chest.

[Experience of complex application of cardiac contractility modulation by Optimizer Smart System and endovascular mitral valve repair by the MitraClip System in the treatment of heart failure]

A 58-year-old female patient with severe chronic heart failure and mitral regurgitation receiving an optimal drug therapy was implanted with an Optimizer Smart device for modulation of cardiac contractility and underwent transcatheter mitral plasty using a MitraClip system. The complex therapy resulted in a significant clinical improvement and beneficial dynamics of echocardiographic parameters.

Ischemic mitral regurgitation: when should one intervene?

PURPOSE OF REVIEW

Optimal timing of intervention for ischemic mitral regurgitation remains to be elucidated. This review summarizes the data on the management of ischemic mitral regurgitation, and their implications on current practice and future research.

RECENT FINDINGS

Mechanistically, ischemic mitral regurgitation can present as Type I, Type IIIb or mixed Type I and IIIb disease. Severity of mitral regurgitation is typically quantified with echocardiography, either transthoracic or transesophageal echocardiography, but may also be assessed via cardiac MRI. In patients with moderate ischemic mitral regurgitation, revascularization can lead to left ventricular reverse remodeling in some. In patients with severe ischemic mitral regurgitation, mitral valve replacement may be associated with fewer adverse events related to heart failure and cardiovascular readmissions, compared with valve repair, although reverse remodeling may be better in patients following successful mitral repair. Transcatheter edge-to-edge repair also further complements the treatment of ischemic mitral regurgitation.

SUMMARY

A tailored approach to patients should be considered for each patient presenting with ischemic mitral regurgitation.

Stress Echocardiography Protocol for Deciding Type of Surgery in Ischemic Mitral Regurgitation: Predictors of Mitral Regurgitation Recurrence following CABG Alone

PURPOSE

Although coronary artery bypass grafting alone (CABGa), or, with mitral annuloplasty (CABGmp), is considered the best therapeutic strategy for patients with ischemic mitral regurgitation (IMR), some recurrences are still reported. The aim of this study was to evaluate the use of the mitral deformation indices (MDI) as a predictor of recurrence of mitral regurgitation in a 12-month follow-up after CABG alone.

METHODS

A total of 145 patients after myocardial infarction with significant IMR, eligible for CABG, were prospectively enrolled in the study. Mitral valve morphology, left ventricle function, IMR degree as assessed by effective regurgitation orifice area (ERO), myocardial viability, and MDI were assessed prior to surgery. Patients were referred for CABGa (gr.1; n = 90) or CABGmp (gr.2; n = 55) based on clinical assessment, and the results of rest and stress echocardiography (exercise echocardiography and low dose dobutamine echocardiography-DBX). One year after surgery, each patient underwent the evaluation of cardiovascular events. Univariable logistic regression analysis was used to identify the factors of recurrence of IMR in 1 year follow-up. Serial echo examinations were performed in all patients at discharge, and at 1 and 12 months after surgery.

RESULTS

Logistic regression analysis revealed that in CABGa, group preoperative changes of tenting area (TA) and coaptation high (CH) during DBX remained the predictors of the recurrence of IMR in 12 months follow-up. TAdbx > 1 cm2 provided a sensitivity of 90% and specificity of 29%, (AUC 0.6436). The best cut-off value for CHdbx was 0.4 cm (sensitivity 90%, specificity 34%; AUC 0.6432). In both groups (CABGa vs. CABGmp) no significant differences were observed in 12-month mortality (1.2% vs. 0%; p = 1.0), hospitalizations due to the heart failure (HF) exacerbation (5.9% vs. 8.5%; p = 0.72), and in the incidence of the composite endpoint (deaths/CV hosp/stroke) (7% vs. 8.5%; p = 0.742).

CONCLUSIONS

The preoperative assessment of MDI changes during dbx can be used to identify patients with IMR qualified to CABG alone at increased risk of recurrence of IMR in 1 year follow-up. Mitral deformation analysis should be used for a better qualification of patients with IMR to the exact surgical approach.

The association between myocardial scar and the response of moderate ischemic mitral regurgitation to isolated coronary artery bypass grafting

Background

The factors that associated with the response of moderate ischemic mitral regurgitation (IMR) to isolated coronary artery bypass grafting (CABG) remain unclear. This study aims to evaluate whether left ventricular (LV) myocardial scar assessed by cardiovascular magnetic resonance (CMR) is associated with the outcome of moderate IMR after isolated CABG.

Methods

Forty-six patients with coronary artery disease (CAD) and moderate IMR who underwent isolated CABG between January 2014 and February 2019 in Anzhen Hospital Affiliated to Capital Medical University were enrolled in this case-control study. All patients underwent CMR and echocardiography before surgery. Patients were classified into two groups according to the severity of IMR 1 year after CABG: an improved group (no or mild IMR) and an unimproved group (moderate or severe IMR). Univariate and multivariate logistic regression analyses were used to assess the association between individual variables and unimproved IMR at 1-year post-CABG.

Results

Compared to patients in the improved group, the patients in the unimproved group had a significantly greater amount of LV myocardial scar (18.0%±9.5% vs. 30.8%±11.2%, P<0.001). In the multiple logistic regression model, after adjustment for age, sex, and body mass index, only LV myocardial scar (OR: 0.89, 95% CI: 0.83–0.96, P=0.001) was independently associated with unimproved IMR after isolated CABG. Furthermore, there was no difference in the 3-year overall survival rates between the two groups (92.3% vs. 90.3%, P=0.46). In addition, patients in the unimproved group had a higher New York Heart Association (NYHA) classification (P=0.01) and more major adverse cardiac events such as MI, angina pectoris, and readmission for heart failure (P=0.03).

Conclusions

A greater amount of preoperative LV myocardial scar was associated with unimproved moderate IMR after isolated CABG. Measuring preoperative LV myocardial scar is helpful to predict post-operative outcome and determine optimal surgery in patients with moderate IMR.

Endothelial-Mesenchymal Transition in Cardiovascular Disease

Endothelial-to-mesenchymal transition is a dynamic process in which endothelial cells suppress constituent endothelial properties and take on mesenchymal cell behaviors. To begin the process, endothelial cells loosen their cell-cell junctions, degrade the basement membrane, and migrate out into the perivascular surroundings. These initial endothelial behaviors reflect a transient modulation of cellular phenotype, that is, a phenotypic modulation, that is sometimes referred to as partial endothelial-to-mesenchymal transition. Loosening of endothelial junctions and migration are also seen in inflammatory and angiogenic settings such that endothelial cells initiating endothelial-to-mesenchymal transition have overlapping behaviors and gene expression with endothelial cells responding to inflammatory signals or sprouting to form new blood vessels. Reduced endothelial junctions increase permeability, which facilitates leukocyte trafficking, whereas endothelial migration precedes angiogenic sprouting and neovascularization; both endothelial barriers and quiescence are restored as inflammatory and angiogenic stimuli subside. Complete endothelial-to-mesenchymal transition proceeds beyond phenotypic modulation such that mesenchymal characteristics become prominent and endothelial functions diminish. In proadaptive, regenerative settings the new mesenchymal cells produce extracellular matrix and contribute to tissue integrity whereas in maladaptive, pathologic settings the new mesenchymal cells become fibrotic, overproducing matrix to cause tissue stiffness, which eventually impacts function. Here we will review what is known about how TGF (transforming growth factor) β influences this continuum from junctional loosening to cellular migration and its relevance to cardiovascular diseases.

Sacubitril/Valsartan: A new dawn has begun!: A revisited review

Heart failure (HF) is among the major causes of global morbidity as well as mortality. Increased prevalence, frequent and prolonged hospitalization, rehospitalization, long-term consumption of healthcare resources, absenteeism, and death upsurge the economic burden linked to HF. For decades, Angiotensin-Converting Enzyme Inhibitors (ACEIs), Angiotensin II Receptor Blockers (ARBs), Beta-Blockers (BBs), and mineralocorticoid receptor antagonists (MRA), have remained the mainstay of the standard of care for HF management. Despite their proven efficacy and cost-effectiveness, HF remains a global pandemic and is still increasing in prevalence. Sacubitril/Valsartan (SAC/VAL) is an Angiotensin Receptor/Neprilysin Inhibitor (ARNI) that proved out to be a game-changer drug in HF treatment. Recent data indicated that SAC/VAL is more efficient and can improve the overall quality of life of HF patients with reduced ejection fraction (HFrEF) with fewer side effects. It is now incorporated in the guidelines as an alternative to ACEIs or ARBs to lower morbidity in addition to mortality in HFrEF patients. This review article will discuss the current guidelines-approved indications and highlight the potential emerging indications, in addition to the currently ongoing clinical trials that will expand the use of SAC/VAL.

Effect of Neprilysin Inhibition for Ischemic Mitral Regurgitation after Myocardial Injury

Angiotensin receptor neprilysin inhibitor (ARNI) treatment reduces functional mitral regurgitation (MR) to a greater extent than angiotensin receptor blocker (ARB) treatment alone, but the mechanism is unclear. We evaluated the mechanisms of how ARNI has an effect on functional MR. After inducing functional MR by left circumflex coronary artery occlusion, male Sprague Dawley rats (n = 31) were randomly assigned to receive the ARNI LCZ696, the ARB valsartan, or corn oil only (MR control). Excised mitral leaflets and left ventricle (LV) were analyzed, and valvular endothelial cells were evaluated focusing on molecular changes. LCZ696 significantly attenuated LV dilatation after 6 weeks when compared with the control group (LV end-diastolic volume, 461.3 ± 13.8 µL versus 525.1 ± 23.6 µL; p < 0.05), while valsartan did not (471.2 ± 8.9 µL; p > 0.05 to control). Histopathological analysis of mitral leaflets showed that LCZ696 strongly reduced fibrotic thickness compared to the control group (28.2 ± 2.7 µm vs. 48.8 ± 7.5 µm; p < 0.05). Transforming growth factor-β and downstream phosphorylated extracellular-signal regulated kinase were also significantly lower in the LCZ696 group. Consequently, excessive endothelial-to-mesenchymal transition (EndoMT) was mitigated in the LCZ696 group compared to the control group and leaflet area was higher (11%) in the LCZ696 group than in the valsartan group. Finally, the MR extent was significantly lower in the LCZ696 group and functional improvement was observed. In conclusion, neprilysin inhibitor has positive effects on LV reverse remodeling and also attenuates fibrosis in MV leaflets and restores adaptive growth by directly modulating EndoMT.

Functional Mitral Regurgitation Outcome and Grading in Heart Failure With Reduced Ejection Fraction

OBJECTIVES

This study aims to define excess-mortality linked to functional mitral regurgitation (FMR) quantified in routine-practice.

BACKGROUND

Appraisal of FMR in heart failure with reduced ejection fraction (HFrEF) is challenging because risks of excess mortality remain uncertain and guidelines diverge.

METHODS

Cases of HFrEF (ejection-fraction <50%) Stage B-C that were diagnosed between 2003 and 2011 and had routine-practice FMR quantitation (FMR cohort, n = 6,381) were analyzed for excess mortality thresholds/rates within the cohort and in comparison to the general population. These were also compared to those of a degenerative mitral regurgitation (DMR) simultaneous cohort (DMR cohort, n = 2,416).

RESULTS

In the FMR cohort (age: 70 ± 11 years, ejection fraction: 36 ± 10%, effective regurgitant orifice area [EROA]: 0.09 ± 0.13 cm²), EROA distribution was skewed towards low-values (≥0.40 cm² in only 8% vs 38% for the DMR cohort; P < 0.0001). One-year mortality was high (15.6%), increasing steeply from 13.3% without FMR to 28.5% with EROA ≥0.30 cm² (adjusted odds ratio: 1.57 [95% CI: 1.19-2.97]; P = 0.001). In the long term, 3,538 FMR cohort patients died with excess mortality threshold ∼0.10 cm² (vs ∼0.20 cm² in the DMR cohort), with 0.10 cm² EROA increments independently associated with considerable mortality increment (adjusted HR: 1.11 [95% CI: 1.08-1.15]; P < 0.0001) and with no detectable interaction. Compared to the general population, FMR excess mortality increased exponentially with higher EROA (risk ratio point estimates 2.8, 3.8, and 5.1 at EROA 0.20, 0.30, and 0.40 cm², respectively), and was much steeper than that of the DMR cohort (P < 0.0001). In nested models, individualized EROA was the strongest FMR survival marker, and a new expanded FMR grading scale based on 0.10 cm² EROA increments provided incremental power over current American Heart Association-American College of Cardiology/European Society of Cardiology guidelines (all P < 0.03).

CONCLUSIONS

In HFrEF, FMR is skewed towards smaller EROA. Nevertheless, when measured in routine practice, EROA is the strongest independent FMR determinant of survival after diagnosis. Excess mortality increases exponentially above the threshold of 0.10 cm², with a much steeper slope than in DMR, for any EROA increment. An expanded EROA-based stratification, superior to existing grading schemes in determining survival, should allow guideline harmonization.

Survival of patients with mild secondary mitral regurgitation with and without mild tricuspid regurgitation

BACKGROUND

Mild secondary mitral regurgitation (SMR) is considered clinically benign when left ventricular ejection fraction (LVEF) is preserved, but evidence on survival associated with mild SMR in normal LVEF is limited.

METHODS

We conducted a retrospective cohort study of patients who underwent echocardiogram in a healthcare network between 2013 and 2018. We compared the survival of 4 groups: no valvular abnormalities (group 1), trace SMR with trace or mild TR (group 2), mild SMR with trace or no TR (group 3), and mild SMR with mild TR (group 4). A Cox proportional hazard model evaluated hazard of death in groups 2-4 compared with group 1, adjusting for demographics, comorbidities, and LVEF. The same comparisons were repeated in a subgroup of patients with preserved LVEF.

RESULTS

Among the 16,372 patients of mean age 61 (51-71) years and 48% women, there were 8,132 (49.7%) group 1 patients, 1,902 (11.6%) group 2 patients, 3,017 (18.4%) group 3 patients, and 3,321 (20.3%) group 4 patients. Compared with group 1, group 4 had significantly increased adjusted hazard of death (hazard ratio [HR]:1.21 (95% confidence interval [CI]1.12-1.31), p<0.001) while groups 2 and 3 did not show a significantly different hazard of death. In those with preserved LVEF, the hazard was also significantly higher in group 4 compared with group 1 (HR1.14, 95%CI 1.03-1.26, p=0.013).

CONCLUSIONS

Mild SMR with mild TR, irrespective of LVEF, was associated with worse survival compared with patients without any valvular abnormalities. Patients with mild SMR may require closer monitoring even with normal LVEF.

Tricuspid regurgitation in ischemic mitral regurgitation patients: prevalence, predictors for outcome and long-term follow-up

Background

Functional tricuspid regurgitation (FTR) is common in left-sided heart pathology involving the mitral valve. The incidence, clinical impact, risk factors, and natural history of FTR in the setting of ischemic mitral regurgitation (IMR) are less known.

Method

We conducted a cohort study based on data collected from January 2012 to December 2014. Patients diagnosed with IMR were eligible for the study. The median follow-up was 5 years. The primary outcome is defined as FTR developing at any stage.

Results

Among the 134 IMR patients eligible for the study, FTR was detected in 29.9% (N = 40, 20.0% mild, 62.5% moderate, and 17.5% severe). In the FTR group, the average age was 60.7 ± 9.2 years (25% females), the mean LV ejection fraction (LVEF) was 37.3 ± 6.45 [%], LA area 46.4 ± 8.06 (mm²), LV internal diastolic diameter (LVIDD) 59.6 ± 3.94 (mm), RV fractional area change 22.3 ± 4.36 (%), systolic pulmonary artery pressure (SPAP) 48.4 ± 9.45 (mmHg). Independent variables associated with FTR development were age ≥ 65y [OR 1.2], failed revascularization, LA area ≥ 42.5 (mm²) [OR 17.1], LVEF ≤ 24% [OR 32.5], MR of moderate and severe grade [OR 419.4], moderate RV dysfunction [OR 91.6] and pulmonary artery pressure of a moderate or severe grade [OR 33.6]. During follow-up, FTR progressed in 39 (97.5%) patients. Covariates independently associated with FTR progression were lower LVEF, RV dysfunction, and PHT of moderate severity. LA area and LVIDD were at the margin of statistical significance (p = 0.06 and p = 0.05, respectively).

Conclusion

In our cohort study, FTR development and progression due to IMR was a common finding. Elderly patients with ischemic MR following unsuccessful PCI are at higher risk. FTR development and severity are directly proportional to LV ejection fraction, to the extent of mitral regurgitation, and SPAP. FTR tends to deteriorate in the majority of patients over a mean of 5-y follow-up.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-01982-y.

Percutaneous Mitral Valve Repair with the MitraClip System in the Current Clinical Practice

Severe mitral valve regurgitation (MR) carries a significant burden both in prognosis and quality of life of patients, as well as on healthcare systems, with high rates of hospitalization for heart failure. While mitral valve surgery constitutes the first-line treatment option for primary MR in suitable patients, surgical treatment for secondary severe MR remains controversial, with a substantial lack of evidence on a survival benefit. In recent decades, percutaneous mitral valve repair has emerged as an alternative treatment for patients deemed not suitable for surgery. Among several devices under development or evaluation, the MitraClip system is the most widespread and is supported by the strongest evidence. While the role of MitraClip in patients with chronic primary MR who are not deemed suitable for surgery is well established, with consistent data showing improvement in both prognosis and quality of life, MitraClip treatment in secondary MR is a rapidly evolving field. Two recent randomized clinical trials generated apparently controversial results but actually provided an interesting pathophysiologic frame that could help discerning patients who will benefit from the procedure versus patients who will not. In this review, we will discuss current treatment options for mitral regurgitation, focusing on percutaneous mitral valve repair with the MitraClip system.

Predictors of moderate to severe ischemic mitral regurgitation after myocardial infarction: a cardiac magnetic resonance study

OBJECTIVES

The purpose of this study is to explore the predictors of moderate to severe ischemic mitral regurgitation (IMR) after myocardial infarction with cardiovascular magnetic resonance (CMR).

METHODS

From January 2016 to September 2018, 109 patients (mean age 60 ± 8 years) with IMR were studied retrospectively. All patients underwent CMR-cine with True-FISP sequence and late gadolinium enhancement (LGE) with a phase-sensitive inversion recovery sequence. The presence of papillary muscle infarction (PMI), global left ventricular (LV) infarcted extent, LV functional parameters, and LV myocardial strain were assessed. Univariate and multivariate analyses were performed to identify factors in the development of moderate to severe IMR.

RESULTS

Mild IMR was present in 61 patients (56%), and moderate to severe IMR was present in 48 patients (44%). PMI was identified in 22 patients (20.1%); 14 of them (63.63%) showed a moderate or severe IMR. Global LV infarcted extent was increased in patients with moderate to severe IMR (p < 0.001). LV functional parameters of patients with moderate to severe IMR were statistically different from those of the patients with mild IMR (all p < 0.001), except the LV SV index (p = 0.142) and LV CI (p = 0.447). The global longitudinal strain (GLS), regional radial strain (RS), and circumferential strain (CS) of the moderate-to-severe IMR group were significantly decreased compared with those of the mild IMR group (p < 0.05). In multivariable analyses, age (OR = 1.11; p = 0.001), global LV infarct extent (OR = 1.14; p = 0.000), and GLS (OR = 1.31; p = 0.000) were associated with moderate-to-severe chronic IMR.

CONCLUSIONS

The incidence of PMI was higher in patients with moderate-to-severe IMR. The extent of global LV infarcted extent and GLS were independent predictors of moderate-to-severe IMR.

KEY POINTS

• Cardiovascular magnetic resonance late gadolinium enhancement and feature-tracking imaging provide reliable information on LV function, myocardial viability, and papillary muscle morphology. • Papillary muscle infarction is not an independent predictor of moderate-to-severe IMR. • The extent of global LV infarction and LV global longitudinal strain were independent predictors of moderate-to-severe chronic IMR.

Causes and mechanisms of isolated mitral regurgitation in the community: clinical context and outcome

AIMS

To define the hitherto unknown aetiology/mechanism distributions of mitral regurgitation (MR) in the community and the linked clinical characteristics/outcomes.

METHODS AND RESULTS

We identified all isolated, moderate/severe MR diagnosed in our community (Olmsted County, MN, USA) between 2000 and 2010 and classified MR aetiology/mechanisms. Eligible patients (n = 727) were 73 ± 18 years, 51% females, with ejection fraction (EF) 49 ± 17%. MR was functional (FMR) in 65%, organic (OMR) in 32% and 2% mixed. Functional MR was linked to left ventricular remodelling (FMR-v) 38% and isolated atrial dilatation (FMR-a) 27%. At diagnosis FMR-v vs. FMR-a, vs. OMR displayed profound differences (all P < 0.0001) in age (73 ± 14, 80 ± 10, 68 ± 21years), male-sex (59, 33, 51%), atrial-fibrillation (28, 54, 13%), EF (33 ± 14, 57 ± 11, 61 ± 10%), and regurgitant-volume (38 ± 13, 37 ± 11, 51 ± 24 mL/beat). Dominant MR mechanism was Type I (normal valve-movement) 38%, Type II (excessive valve-movement) 25%, Type IIIa (diastolic movement-restriction) 3%, and Type IIIb (systolic movement-restriction) 34%. Outcomes were mediocre with excess-mortality vs. general-population in FMR-v [risk ratio 3.45 (2.98-3.99), P < 0.0001] but also FMR-a [risk ratio 1.88 (1.52-2.25), P < 0.0001] and OMR [risk ratio 1.83 (1.50-2.22), P < 0.0001]. Heart failure was frequent, particularly in FMR-v (5-year 83 ± 3% vs. 59 ± 4% FMR-a, 40 ± 3% OMR, P < 0.0001). Mitral surgery during patients' lifetime was performed in 4% of FMR-v, 3% of FMR-a, and 37% of OMR.

CONCLUSION

Moderate/severe isolated MR in the community displays considerable aetiology/mechanism heterogeneity. Functional MR dominates, mostly FMR-v but FMR-a is frequent and degenerative MR dominates OMR. Outcomes are mediocre with excess-mortality particularly with FMR-v but FMR-a, despite normal EF incurs notable excess-mortality and frequent heart failure. Pervasive undertreatment warrants clinical trials of therapies tailored to specific MR cause/mechanisms.

Long Term Survival After Surgery for Ischaemic Mitral Regurgitation: A Single Centre Australian Experience

BACKGROUND

Ischaemic mitral regurgitation (IMR) is associated with an increase in both mortality and congestive heart failure in patients undergoing coronary artery bypass grafting (CABG). Intervention for moderate to severe IMR involves either valve repair or replacement. The ideal option is yet to be fully defined with relatively poor long-term survival being noted in the literature.

METHOD

A retrospective observational study was conducted to review the outcomes of patients undergoing CABG in combination with either mitral valve repair (MVr) or mitral valve replacement (MVR) for concurrent coronary artery disease with moderate to severe IMR at The Prince Charles Hospital in Brisbane between the years 2002 to 2015.

RESULTS

One hundred and five (105) patients were included, 81 patients (77%) undergoing CABG and MVr and 24 patients (23%) undergoing CABG and MVR. There was no difference in 30-day mortality between the two groups (1% in MVr and 0% in MVR, p=0.589), however patients in the MVr group were significantly more likely, in univariate and multivariate analysis, to develop at least moderate MR (40% v. 8%, p=0.006). The 5-year survival was 87% and 55% at 10 years.

CONCLUSIONS

In patients undergoing CABG and mitral valve intervention for IMR, long-term mortality remains high. There was no difference in short- or long-term mortality between repair and replacement although recurrence of at least moderate mitral regurgitation was significantly higher with mitral valve repair.

MITRA-FR vs. COAPT: lessons from two trials with diametrically opposed results

Percutaneous mitral valve repair using the MitraClip device has been proposed to correct secondary mitral regurgitation (MR). Recently, the results of two randomized controlled trials, that is MITRA-FR (Percutaneous Repair with the MitraClip Device for Severe Functional/Secondary Mitral Regurgitation) and COAPT (Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients with Functional Mitral Regurgitation), assessing the efficacy and safety of MitraClip in patients with systolic heart failure and severe secondary MR were published. A priori, these two trials targeted the same patient populations with the same disease using the same device but the results of these trials were diametrically opposed, MITRA-FR being neutral and COAPT being highly positive with respect to efficacy of the MitraClip procedure. The objectives of this viewpoint are: (i) to highlight not only the similarities but also the differences between MITRA-FR and COAPT, which may explain the strikingly different results and conclusions between these two trials and (ii) to derive from these results, implications with regards to the application of the MitraClip procedure in clinical practice.

Impact of Mitral Regurgitation Severity and Left Ventricular Remodeling on Outcome After MitraClip Implantation: Results From the Mitra-FR Trial

OBJECTIVES

This study aimed to identify a subset of patients based on echocardiographic parameters who might have benefited from transcatheter correction using the MitraClip system in the MITRA-FR (Percutaneous Repair with the MitraClip Device for Severe Functional/Secondary Mitral Regurgitation) trial.

BACKGROUND

It has been suggested that differences in the degree of mitral regurgitation (MR) and left ventricular (LV) remodeling may explain the conflicting results between the MITRA-FR and the COAPT (Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients with Functional Mitral Regurgitation) trials.

METHODS

In a post hoc analysis, we evaluated the interaction between the intervention and subsets of patients defined based on MR severity (effective regurgitant orifice [ERO], regurgitant volume [RVOL] and regurgitant fraction [RF]), LV remodeling (end-diastolic and end-systolic diameters and volumes) and combination of these parameters with respect to the composite of death from any cause or unplanned hospitalization for heart failure at 24 months.

RESULTS

We observed a neutral impact of the intervention in subsets with the highest MR degree (ERO ≥30 mm², RVOL ≥45 ml or RF ≥50%) as in patients with milder MR degree. The same was seen in subsets with the milder LV remodeling using either diastolic or systolic diameters or volumes. When parameters of MR severity and LV remodeling were combined, there was still no benefit of the intervention including in the subset of patients with an ERO/end-diastolic volume ratio ≥ 0.15 despite similar ERO and LV end-diastolic volume compared with COAPT patients.

CONCLUSIONS

In the MITRA-FR trial, we could not identify a subset of patients defined based on the degree of the regurgitation, LV remodeling or on their combination, including those deemed as having disproportionate MR, that might have benefited from transcatheter correction using the MitraClip system. (Multicentre Study of Percutaneous Mitral Valve Repair MitraClip Device in Patients With Severe Secondary Mitral Regurgitation [MITRA-FR]; NCT01920698).

Regurgitant Volume/Left Ventricular End-Diastolic Volume Ratio: Prognostic Value in Patients With Secondary Mitral Regurgitation

OBJECTIVES

The purpose of this study was to investigate the prognostic implications of the ratio of mitral regurgitant volume (RVol) to left ventricular (LV) end-diastolic volume (EDV) in patients with significant secondary mitral regurgitation (MR).

BACKGROUND

Quantification of secondary MR remains challenging, and its severity can be over- or underestimated when using the proximal isovelocity surface area method, which does not take LV volume into account. This limitation can be addressed by normalizing mitral RVol to LVEDV.

METHODS

A total of 379 patients (mean age 67 ± 11 years; 63% male) with significant (moderate and severe) secondary MR were divided into 2 groups according to the RVol/EDV ratio: RVol/EDV ≥20% (greater MR/smaller EDV) and <20% (smaller MR/larger EDV). The primary endpoint was all-cause mortality.

RESULTS

During median (interquartile range) follow-up of 50 (26 to 94) months, 199 (52.5%) patients died. When considering patients receiving medical therapy only, patients with RVol/EDV ratio ≥20% tended to have higher mortality rates than those with RVol/EDV ratio <20% (5-year estimated rates 24.1% vs. 18.4%, respectively; p = 0.077). Conversely, when considering the entire follow-up period including mitral valve interventions, patients with a higher RVol/EDV ratio (≥20%) had lower rates of all-cause mortality compared with patients with RVol/EDV ratio <20% (5-year estimated rates 39.0% vs. 44.8%, respectively; p = 0.018). On multivariable analysis, higher RVol/EDV ratio (per 5% increment as a continuous variable) was independently associated with lower all-cause mortality (0.93; p = 0.023).

CONCLUSIONS

In patients with significant secondary MR treated medically, survival tended to be lower in those with a higher RVol/EDV ratio. Conversely, a higher RVol/EDV ratio was independently associated with reduced all-cause mortality. when mitral valve interventions were taken into consideration.

An observational, prospective study on surgical treatment of secondary mitral regurgitation: The SMR study. Rationale, purposes, and protocol

The natural history of secondary mitral regurgitation (MR) is unfavorable. Nevertheless, there are no evidence that its correction can improve the outcome. If from one side the original cause of secondary MR can be such to limit the possibilities of improvement, from the other side it is possible that the surgical technique widely applied to repair, restrictive mitral annuloplasty, is not adequate to correct the regurgitation. The addition of valvular and/or subvalvular techniques has been considered a possible technical solution. However, we do not know the prevalence of each technique, how many times mitral replacement is used to correct secondary MR. This aspect is of particular importance, as we know that a successful mitral repair causes a better left ventricular systolic remodeling than a unsuccessful repair or replacement. This study is a prospective, observational registry, conceived to understand what is done in the real world. Any surgeon will use the technique he thinks the most suitable for the patient. Every year, for 5 years, patients will have a clinical and echocardiographic follow-up, to evaluate the risk factors for a worse result (death, rehospitalization for heart failure, reoperation for MR return, moderate, or more MR return). This knowledge will give us the possibility to understand which is the technique, or the strategy, more efficient to treat this disease and the real efficacy of the surgical treatment.

Dismal Outcomes and High Societal Burden of Mitral Valve Regurgitation in France in the Recent Era: A Nationwide Perspective

Background Although US recent data suggest that mitral regurgitation (MR) is severely undertreated and carries a poor outcome, population-based views on outcome and management are limited. We aimed to define the current treatment standards, clinical outcomes, and costs related to MR at the nationwide level. Methods and Results In total, 107 412 patients with MR were admitted in France in 2014 to 2015. Within 1 year, 8% were operated and 92% were conservatively managed and constituted our study population (68% primary MR and 32% secondary MR). The mean age was 77±15 years; most patients presented with comorbidities. In-hospital and 1-year mortality rates were 4.1% and 14.3%, respectively. Readmissions were common (63% at least once and 37% readmitted ≥2 times). Rates of 1-year mortality or all-cause readmission and 1-year mortality or heart failure readmission were 67% and 34%, respectively, and increased with age, Charlson index, heart failure at admission, and secondary MR etiology; however, the event rate remained notably high in the primary MR subset (64% and 28%, respectively). The mean costs of hospital admissions and of readmissions were 5345±6432 and 10 080±10 847 euros, respectively. Conclusions At the nationwide level, MR was a common reason for admission and affected an elderly population with frequent comorbidities. Less than 10% of patients underwent a valve intervention. All subsets of patients who were conservatively managed incurred high mortality and readmissions rates, and MR represented a major societal burden with an extrapolated annual cost of 350 to 550 million euros (390-615 million US dollars). New strategies to improve the management and outcomes of patients with both primary and secondary MR are critical and warranted.

Secondary valve regurgitation in patients with heart failure with preserved ejection fraction, heart failure with mid-range ejection fraction, and heart failure with reduced ejection fraction

Secondary mitral regurgitation and secondary tricuspid regurgitation due to heart failure (HF) remain challenging in almost every aspect: increasing prevalence, poor prognosis, notoriously elusive in diagnosis, and complexity of therapeutic management. Recently, defined HF subgroups according to three ejection fraction (EF) ranges (reduced, mid-range, and preserved) have stimulated a structured understanding of the HF syndrome but the role of secondary valve regurgitation (SVR) across the spectrum of EF remains undefined. This review expands this structured understanding by consolidating the underlying phenotype of myocardial impairment with each type of SVR. Specifically, the current understanding, epidemiological considerations, impact, public health burden, mechanisms, and treatment options of SVR are discussed separately for each lesion across the HF spectrum. Furthermore, this review identifies important gaps in knowledge, future directions for research, and provides potential solutions for diagnosis and treatment. Mastering the challenge of SVR requires a multidisciplinary collaborative effort, both, in clinical practice and scientific approach to optimize patient outcomes.

Feasibility of a Mitral Annuloplasty With the Capability for Peri- and Postoperative Adjustment

Surgical repair with implantation of a mitral annuloplasty ring is the gold standard treatment for mitral regurgitation. However, outcomes are variable and recurrent mitral regurgitation is not uncommon. A REshapeable Mitral Annuloplasty DevIce (REMADI) is proposed, which consists of a fully encapsulated low melting temperature alloy. The alloy is solid and rigid at body temperature and provides traction force to shape the annulus. When heated using a noncontact method, the alloy melts and the REMADI becomes malleable. The REMADI is engaged with the mitral valve annulus using anchors which automatically deploy upon contact. A passive beating porcine heart model was used to demonstrate the feasibility of the REMADI device, which was deployed, engaged, and used to reduce the diameter of the mitral valve annulus.

The Prognostic Importance of TAPSE in Early and in Stable Cardiovascular Diseases

The identification of predictors of major cardiovascular events (MACES) represents a big challenge, especially in early and stable cardiovascular diseases. This prospective study comparatively evaluated the prognostic importance of left ventricular (LV) and right ventricular (RV) systolic and diastolic function, pulmonary artery pressure (PAP) and pulmonary vascular resistance (PVR) in a stable patient’s cohort with cardiovascular risk factors. The LV ejection fraction, mitral annular plane systolic excursion (MAPSE), tricuspid annular plane systolic excursion (TAPSE), functional mitral regurgitation (FMR), doppler tissue imaging of mitral and tricuspid annulus with systolic and diastolic peaks estimation, tricuspid regurgitation velocity (TRV), pulmonary velocity outflow time integral (PVTI), mean pulmonary artery pressure (MPAP) and PVR were estimated at enrollment. During the follow-up, MACES and all-cause mortality were recorded. 369 subjects with or without previous MACES were enrolled. Bivariate analysis revealed LVEF, TAPSE, MPAP, TRV, PVR, LV diastolic function, and FMR were associated with the endpoints. When computing the influence of covariates to the primary endpoint (all-cause mortality and MACES) through Cox analysis, only LV diastolic function and TAPSE entered the final model; for the secondary endpoint (MACES) only TAPSE entered. TAPSE was able to predict MACES and all-cause mortality in early and stable cardiovascular diseases. The use of TAPSE should be implemented.

Association of Machine Learning-Derived Phenogroupings of Echocardiographic Variables with Heart Failure in Stable Coronary Artery Disease: The Heart and Soul Study

BACKGROUND

Many individual echocardiographic variables have been associated with heart failure (HF) in patients with stable coronary artery disease (CAD), but their combined utility for prediction has not been well studied.

METHODS

Unsupervised model-based cluster analysis was performed by researchers blinded to the study outcome in 1,000 patients with stable CAD on 15 transthoracic echocardiographic variables. We evaluated associations of cluster membership with HF hospitalization using Cox proportional hazards regression analysis.

RESULTS

The echo-derived clusters partitioned subjects into four phenogroupings: phenogroup 1 (n = 85) had the highest levels, phenogroups 2 (n = 314) and 3 (n = 205) displayed intermediate levels, and phenogroup 4 (n = 396) had the lowest levels of cardiopulmonary structural and functional abnormalities. Over 7.1 ± 3.2 years of follow-up, there were 198 HF hospitalizations. After multivariable adjustment for traditional cardiovascular risk factors, phenogroup 1 was associated with a nearly fivefold increased risk (hazard ratio [HR] = 4.8; 95% CI, 2.4-9.5), phenogroup 2 was associated with a nearly threefold increased risk (HR = 2.7; 95% CI, 1.4-5.0), and phenogroup 3 was associated with a nearly twofold increased risk (HR = 1.9; 95% CI, 1.0-3.8) of HF hospitalization, relative to phenogroup 4.

CONCLUSIONS

Transthoracic echocardiographic variables can be used to classify stable CAD patients into separate phenogroupings that differentiate cardiopulmonary structural and functional abnormalities and can predict HF hospitalization, independent of traditional cardiovascular risk factors.

Refining the prognostic impact of functional mitral regurgitation in chronic heart failure

Aims

Significant efforts are currently undertaken to reduce functional mitral regurgitation (FMR) in patients with chronic heart failure in the hope to improve prognosis. We aimed to assess the prognostic impact of FMR in heart failure with reduced ejection fraction (HFrEF) under optimal medical therapy (OMT) and various conditions of HFrEF. We further intended to identify a heart failure phenotype, where FMR is most likely a driving force and not a mere bystander of the disease.

Methods and results

We prospectively included 576 consecutive HFrEF patients into our long-term observational study. Functional [i.e. New York Heart Association (NYHA) class], echocardiographic, invasive haemodynamic, and biochemical (i.e. NT-proBNP, MR-proANP, MR-proADM, CT-proET-1, copeptin) measurements were performed at baseline. During a median follow-up of 62 months (interquartile range 52-76), 47% of patients died. Severe FMR was a significant predictor of mortality [hazard ratio (HR) 1.76, 95% confidence interval (CI) 1.34-2.30; P < 0.001], independent of clinical (adjusted HR 1.61, 95% CI 1.22-2.12; P = 0.001), and echocardiographic (adjusted HR 1.46, 95% CI 1.09-1.94; P = 0.01) confounders, OMT (adjusted HR 1.81, 95% CI 1.25-2.63; P = 0.002), and neurohumoral activation (adjusted HR 1.38, 95% CI 1.03-1.84; P = 0.03). Subanalysis revealed that severe FMR was associated with poor outcome in an intermediate-failure phenotype of HFrEF i.e. patients with NYHA class II (adjusted HR 2.17, 95% CI 1.07-4.44; P = 0.03) and III (adjusted HR 1.80, 95% CI 1.17-2.77; P = 0.008), moderately reduced left ventricular function (adjusted HR 2.37, 95% CI 1.36-4.12; P = 0.002), and within the second quartile (871-2360 pg/mL) of NT-proBNP (adjusted HR 2.16, 95% CI 1.22-3.86; P = 0.009).

Conclusion

In a patient cohort under OMT, the adverse prognostic impact of FMR is given predominantly in a sub-cohort of a specific intermediate-failure phenotype-well-defined functionally, haemodynamically, biochemically, and morphologically.

Diagnosis and Management of Ischemic Mitral Regurgitation: Evidence-Based Clinical Decision Making at the Point of Care

Anatomical, functional, and pathophysiologic mechanisms of ischemic mitral regurgitation (IMR) are markedly different from the primary mitral regurgitation. The older and ubiquitous cutoff of EROA (effective regurgitant orifice area) and Rvol (regurgitant volume) for IMR has been reinstated in the new guideline after a brief hiatus. There had always been a lack of good-quality evidence for its introduction for guiding IMR severity in the previous guideline, and we still do not have quality evidences that could justify its reintroduction. Unlike primary MR, IMR is usually associated with reduced ejection fraction. Therefore, it appears unrealistic to keep the similar cutoff for primary MR and IMR. The cutoff of severity can be modified according to projected values of Rvol normalized to ejection fraction and EROA normalized to Rvol. In addition, the treatment outcome in these patients is determined by factors (left ventricular dyssynchrony, annular dilatation, tenting area, tenting height, tenting volume, and myocardial viability) other than the simple grading. In this review article, a series of graph have been constructed from the numerical data derived from the literatures on IMR to depict the relationship between EROA, Rvol, left ventricular end diastolic volume, and ejection fraction in order to obtain a reasonable projection formula for EROA and Rvol. Furthermore, a management algorithm has been proposed for patients with IMR undergoing coronary artery bypass grafting based on echocardiographic predictors that influence the postoperative outcome.

Mitral regurgitation worsens cardiac remodeling in ischemic cardiomyopathy in an experimental model

OBJECTIVE

Mitral regurgitation (MR) developing concomitant with ischemic cardiomyopathy is a frequently diagnosed valvular lesion, for which an optimal therapeutic strategy is unknown. The contribution of MR to the ongoing cardiac remodeling from myocardial infarction (MI) remains controversial. We have developed a novel experimental model in which MI and severe MR can be independently introduced, to study the role of MR in chronic remodeling of the ischemic heart.

METHODS

A total of 98 rats were induced with MI+MR (group 1), MI (group 2), MR (group 3), or sham surgery (group 4). MR was induced by inserting a needle into the anterior mitral leaflet via the ventricular apex in a beating heart. MI was induced by ligating the left coronary artery. Biweekly ultrasound examinations were performed after surgery, and invasive hemodynamic assessments were performed in some rats at 2, 10, and 20 weeks.

RESULTS

At 2 weeks postsurgery, the mean end-diastolic volume was 432 ± 103 μL in ischemic hearts with MR, compared with 390 ± 76.3 μL in ischemic hearts without MR (a 10.76% difference). By 20 weeks, the mean volume was significantly greater in the former group (767 ± 246 μL vs 580 ± 85 μL; a 32.24% difference). At 2 weeks, mean end-systolic volume was 147 ± 46.8 μL in the ischemic hearts with MR and 147 ± 45.7 μL in those without MR. By 20 weeks, the mean volumes had increased to 357 ± 136.4 μL and 271 ± 82.3 μL, respectively (a 31.73% difference).

CONCLUSIONS

MR in ischemic hearts significantly increased end-diastolic and end-systolic volumes of the left ventricle, indicating adverse cardiac remodeling and worse systolic function.

Early and long-term results of surgery for secondary mitral regurgitation with a damaged heart

BACKGROUND

Surgery for secondary mitral regurgitation is still controversial, especially when the left ventricle is damaged. The Mitra Clip has been shown to be safe and effective for certain patient groups but does not offer superior control of mitral regurgitation compared with the surgery. If performed safely, the surgery can provide greater benefits over the long-term. The objective of this study was to retrospectively investigate the early and long-term results of mitral valve surgery for secondary mitral valve regurgitation with a damaged, dilated left ventricle.

METHODS

Patients with ejection fraction <40% and left ventricular end-diastolic/systolic diameter >50/40 mm who underwent mitral valve surgery for secondary mitral regurgitation were investigated retrospectively.

RESULTS

The mean age of the 80 identified cases was 65.7 years, and 63 patients were male. Preoperative echocardiograms showed a mean ejection fraction of 25.2% and mean left ventricular diameters in diastole/systole of 64.5/56.9 mm, respectively. Mitral valve replacement was performed in 39 cases, and mitral valve plasty in 41 cases. The most common concomitant procedures were coronary artery bypass grafting and tricuspid valve surgery (41.3% each). Mitral regurgitation improved significantly from 3.5 to 0.83, and no operative or in-hospital deaths were encountered. Long-term results showed actual 1-, 3- and 5-year survival rates of 93.1%, 80.0%, and 64.7%, respectively (mean follow-up, 1264 days).

CONCLUSIONS

Early results of this study were good and long-term results were acceptable. Our results suggest that mitral valve surgery is feasible for secondary mitral valve regurgitation even in dilated, damaged hearts.

Transcatheter Valve Repair for Patients With Mitral Regurgitation: 30-Day Results of the CLASP Study

OBJECTIVES

The authors report the procedural and 30-day results of the PASCAL Transcatheter Valve Repair System (Edwards Lifesciences, Irvine, California) in patients with mitral regurgitation (MR) enrolled in the multicenter, prospective, single-arm CLASP study.

BACKGROUND

Severe MR may lead to symptoms, impaired quality of life, and reduced functional capacity when untreated.

METHODS

Eligible patients had grade 3+ or 4+ MR despite optimal medical therapy and were deemed appropriate for the study by the local heart team. All outcomes were assessed through 30 days post-procedure. Major adverse events (MAEs) were adjudicated by an independent clinical events committee, and echocardiographic images were assessed by a core laboratory. The primary safety endpoint was the rate of MAEs at 30 days.

RESULTS

Between June 2017 and September 2018, 62 patients with grade 3+ or 4+ MR were enrolled. The mean age was 76.5 years, and 51.6% of patients were in New York Heart Association functional class III or IV, with 56% functional, 36% degenerative, and 8% mixed MR etiology. At 30 days, the MAE rate was 6.5%, with an all-cause mortality rate of 1.6% and no occurrence of stroke; 98% had MR grade ≤2+, with 86% with MR grade ≤1+ (p < 0.0001); and 85% were in New York Heart Association functional class I or II (p < 0.0001). Six-minute walk distance improved by 36 m (p = 0.0018), and Kansas City Cardiomyopathy Questionnaire and EQ-5D scores improved by 17 (p < 0.0001) and 10 (p = 0.0004) points, respectively.

CONCLUSIONS

The PASCAL repair system showed feasibility and acceptable safety in the treatment of patients with grade 3+ or 4+ MR. MR severity, irrespective of etiology, was significantly reduced and accompanied by clinically and statistically significant improvements in functional status, exercise capacity, and quality of life. (The CLASP Study Edwards PASCAL Transcatheter Mitral Valve Repair System Study; NCT03170349).