Effect of captopril on functional mitral regurgitation in dilated heart failure: a randomised double blind placebo controlled trial

Percutaneous repair of moderate-to-severe or severe functional mitral regurgitation in patients with symptomatic heart failure: Baseline characteristics of patients in the RESHAPE-HF2 trial and comparison to COAPT and MITRA-FR trials

AIM

The RESHAPE-HF2 trial is designed to assess the efficacy and safety of the MitraClip device system for the treatment of clinically important functional mitral regurgitation (FMR) in patients with heart failure (HF). This report describes the baseline characteristics of patients enrolled in the RESHAPE-HF2 trial compared to those enrolled in the COAPT and MITRA-FR trials.

METHODS AND RESULTS

The RESHAPE-HF2 study is an investigator-initiated, prospective, randomized, multicentre trial including patients with symptomatic HF, a left ventricular ejection fraction (LVEF) between 20% and 50% with moderate-to-severe or severe FMR, for whom isolated mitral valve surgery was not recommended. Patients were randomized 1:1 to a strategy of delivering or withholding MitraClip. Of 506 patients randomized, the mean age of the patients was 70 ± 10 years, and 99 of them (20%) were women. The median EuroSCORE II was 5.3 (2.8-9.0) and median plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) was 2745 (1407-5385) pg/ml. Most patients were prescribed beta-blockers (96%), diuretics (96%), angiotensin-converting enzyme inhibitors/angiotensin receptor blockers/angiotensin receptor-neprilysin inhibitors (82%) and mineralocorticoid receptor antagonists (82%). The use of sodium-glucose cotransporter 2 inhibitors was rare (7%). Cardiac resynchronization therapy (CRT) devices had been previously implanted in 29% of patients. Mean LVEF, left ventricular end-diastolic volume and effective regurgitant orifice area (EROA) were 31 ± 8%, 211 ± 76 ml and 0.25 ± 0.08 cm2, respectively, whereas 44% of patients had mitral regurgitation severity of grade 4+. Compared to patients enrolled in COAPT and MITRA-FR, those enrolled in RESHAPE-HF2 were less likely to have mitral regurgitation grade 4+ and, on average, HAD lower EROA, and plasma NT-proBNP and higher estimated glomerular filtration rate, but otherwise had similar age, comorbidities, CRT therapy and LVEF.

CONCLUSION

Patients enrolled in RESHAPE-HF2 represent a third distinct population where MitraClip was tested in, that is one mainly comprising of patients with moderate-to-severe FMR instead of only severe FMR, as enrolled in the COAPT and MITRA-FR trials. The results of RESHAPE-HF2 will provide crucial insights regarding broader application of the transcatheter edge-to-edge repair procedure in clinical practice.

Randomized investigation of the MitraClip device in heart failure: Design and rationale of the RESHAPE-HF2 trial design

AIMS

The safety and effectiveness of the MitraClip device to treat functional mitral regurgitation (FMR) has been tested in previous clinical trials yielding somewhat heterogeneous results in heart failure (HF) patients. Over time, the MitraClip device system has been modified and clinical practice evolved to consider also less severely diseased HF patients with FMR for this therapeutic option. The RESHAPE-HF2 trial aims to assess the safety and effectiveness of the MitraClip device system on top of medical therapy considered optimal in the treatment of clinically significant FMR in symptomatic patients with chronic HF.

METHODS

The RESHAPE-HF2 is an investigator-initiated, prospective, randomized, parallel-controlled, multicentre trial designed to evaluate the use of the MitraClip device (used in the most up-to-date version as available at sites) plus optimal standard of care therapy (device group) compared to optimal standard of care therapy alone (control group). Eligible subjects have signs and symptoms of HF (New York Heart Association [NYHA] class II-IV despite optimal therapy), and have moderate-to-severe or severe FMR, as confirmed by a central echocardiography core laboratory; have an ejection fraction between ≥20% and ≤50% (initially 15-35% for NYHA class II patients, and 15-45% for NYHA class III/IV patients); have been adequately treated per applicable standards, and have received appropriate revascularization and cardiac resynchronization therapy, if eligible; had a HF hospitalization or elevated natriuretic peptides (B-type natriuretic peptide [BNP] ≥300 pg/ml or N-terminal proBNP ≥1000 pg/ml) in the last 90 days; and in whom isolated mitral valve surgery is not a recommended treatment option. The trial has three primary endpoints, which are these: (i) the composite rate of total (first and recurrent) HF hospitalizations and cardiovascular death during 24 months of follow-up, (ii) the rate of total (i.e. first and recurrent) HF hospitalizations within 24 months, and (iii) the change from baseline to 12 months in the Kansas City Cardiomyopathy Questionnaire overall score. The three primary endpoints will be analysed using the Hochberg procedure to control the familywise type I error rate across the three hypotheses.

CONCLUSIONS

The RESHAPE-HF2 trial will provide sound evidence on the MitraClip device and its effects in HF patients with FMR. The recruitment was recently completed with 506 randomized patients.

Functional Mitral Regurgitation: Patient Selection and Optimization

Functional mitral regurgitation appears commonly among all heart failure phenotypes and can affect symptom burden and degree of maladaptive remodeling. Transcatheter mitral valve edge-to-edge repair therapies recently became an important part of the routine heart failure armamentarium for carefully selected and medically optimized candidates. Patient selection is considering heart failure staging, relevant comorbidities, as well as anatomic criteria. Indications and device platforms are currently expanding.

Predictive Factors of Cardiac Mortality Following TEER in Patients with Secondary Mitral Regurgitation

Background: Transcatheter edge-to-edge mitral valve repair (TEER) has emerged as a viable approach to addressing substantial secondary mitral regurgitation. In the contemporary landscape where ultimate heart failure-specific therapies, such as cardiac replacement modalities, are available, prognosticating a high-risk cohort susceptible to early cardiac mortality post-TEER is pivotal for formulating an effective therapeutic regimen. Methods: Our study encompassed individuals with secondary mitral regurgitation and chronic heart failure enlisted in the multi-center (Optimized CathEter vAlvular iNtervention (OCEAN)-Mitral registry. We conducted an assessment of baseline variables associated with cardiac death within one year following TEER. Results: Amongst the 1517 patients (median age: 78 years, 899 males), 101 experienced cardiac mortality during the 1-year observation period after undergoing TEER. Notably, a history of heart failure-related admissions within the preceding year, utilization of intravenous inotropes, and elevated plasma B-type natriuretic peptide levels emerged as independent prognosticators for the primary outcome (p < 0.05 for all). Subsequently, we devised a novel risk-scoring system encompassing these variables, which significantly stratified the cumulative incidence of the 1-year primary outcome (16%, 8%, and 4%, p < 0.001). Conclusions: Our study culminated in the development of a new risk-scoring system aimed at predicting 1-year cardiac mortality post-TEER.

Valvular heart disease and cardiomyopathy: reappraisal of their interplay

Cardiomyopathies and valvular heart diseases are typically considered distinct diagnostic categories with dedicated guidelines for their management. However, the interplay between these conditions is increasingly being recognized and they frequently coexist, as in the paradigmatic examples of dilated cardiomyopathy and hypertrophic cardiomyopathy, which are often complicated by the occurrence of mitral regurgitation. Moreover, cardiomyopathies and valvular heart diseases can have a shared aetiology because several genetic or acquired diseases can affect both the cardiac valves and the myocardium. In addition, the association between cardiomyopathies and valvular heart diseases has important prognostic and therapeutic implications. Therefore, a better understanding of their shared pathophysiological mechanisms, as well as of the prevalence and predisposing factors to their association, might lead to a different approach in the risk stratification and management of these diseases. In this Review, we discuss the different scenarios in which valvular heart diseases and cardiomyopathies coexist, highlighting the need for an improved classification and clustering of these diseases with potential repercussions in the clinical management and, particularly, personalized therapeutic approaches.

Mitral Interventions in Heart Failure

Patients with heart failure with reduced ejection fraction who have secondary mitral regurgitation (SMR) have poorer outcomes and quality of life than those without SMR. Guideline-directed medical therapy is the cornerstone of SMR treatment. Careful evaluation of landmark trials using mitral transcatheter edge-to-edge repair in SMR has led to an improved understanding of who will benefit from percutaneous interventions with emphasis on a multidisciplinary approach. The success with mitral transcatheter edge-to-edge repair in SMR has also spurred the evaluation of its role in populations that were not initially studied, such as end-stage heart failure and cardiogenic shock. A spectrum of transcatheter devices in development and clinical trials promise to further provide a growing array of management options for heart failure with reduced ejection fraction patients with symptomatic SMR.

New Perspective on Pathophysiology and Management of Functional Mitral Regurgitation

Functional mitral regurgitation (FMR) occurs as a result of global or segmental left ventricular (LV) dysfunction or left atrial dilatation, leading to mitral annular dilatation, papillary muscle displacement, mitral valve (MV) leaflet tethering, and leaflet remodeling. The prevalence of FMR continues to rise in the United States. Even mild FMR is associated with adverse clinical outcomes. Echocardiography is the primary imaging modality used to assess the type and severity of mitral regurgitation. FMR treatment depends on the etiology. Evidence-based pharmacologic and cardiac resynchronization therapies for underlying LV dysfunction remain the mainstay of treatment. Patients who remain symptomatic despite optimal medical therapy can be considered for surgical or percutaneous MV intervention. This article reviews the pathophysiology, imaging evaluation, and therapeutic options of FMR, highlighting the most recent developments in a rapidly evolving field.

Medical Therapy for Functional Mitral Regurgitation

Functional mitral regurgitation (FMR) can be broadly categorized into 2 main groups: ventricular and atrial, which often coexist. The former is secondary to left ventricular remodeling usually in the setting of heart failure with reduced ejection fraction or less frequently due to ischemic papillary muscle remodeling. Atrial FMR develops due to atrial and annular dilatation related to atrial fibrillation/flutter or from increased atrial pressures in the setting of heart failure with preserved ejection fraction. Guideline-directed medical therapy is the first step and prevails as the mainstay in the treatment of FMR. In this review, we address the medical therapeutic options for FMR management and highlight a targeted approach for each FMR category. We further address important clinical and echocardiographic characteristics to aid in determining when medical therapy is expected to have a low yield and an appropriate window for effective interventional approaches exists.

Percutaneous Edge-to-Edge Mitral Valve Repair for Functional Mitral Regurgitation

The presence and severity of functional mitral regurgitation (FMR) is associated with worse outcomes in patients with heart failure and reduced ejection fraction. Prior to the availability of percutaneous mitral valve repair, management for FMR has been limited to medical therapy, cardiac resynchronization therapy for a specific subset of patients and surgery which has yet to demonstrate mortality benefits. Transcatheter edge-to-edge repair (TEER) of the mitral valve has emerged in the past decade as an invaluable member of the armamentarium against FMR with the 2 landmark randomized controlled trials providing deep insights on patient selection. In addition, TEER has spurred the rapid advancement in our understanding of FMR. This article seeks to provide an overview as well as our current understanding on the role of TEER in FMR.

Clinical impact of changes in mitral regurgitation severity after medical therapy optimization in heart failure

Background

Few data are available regarding changes in mitral regurgitation (MR) severity with guideline-recommended medical therapy (GRMT) in heart failure (HF). Our aim was to evaluate the evolution and impact of MR after GRMT in the Biology study to Tailored treatment in chronic heart failure (BIOSTAT-CHF).

Methods

A retrospective post-hoc analysis was performed on HF patients from BIOSTAT-CHF with available data on MR status at baseline and at 9-month follow-up after GRMT optimization. The primary endpoint was a composite of all-cause death or HF hospitalization.

Results

Among 1022 patients with data at both time-points, 462 (45.2%) had moderate-severe MR at baseline and 360 (35.2%) had it at 9-month follow-up. Regression of moderate-severe MR from baseline to 9 months occurred in 192/462 patients (41.6%) and worsening from baseline to moderate-severe MR at 9 months occurred in 90/560 patients (16.1%). The presence of moderate-severe MR at 9 months, independent from baseline severity, was associated with an increased risk of the primary endpoint (unadjusted hazard ratio [HR], 2.03; 95% confidence interval [CI], 1.57–2.63; p < 0.001), also after adjusting for the BIOSTAT-CHF risk-prediction model (adjusted HR, 1.85; 95% CI 1.43–2.39; p < 0.001). Younger age, LVEF ≥ 50% and treatment with higher ACEi/ARB doses were associated with a lower likelihood of persistence of moderate-severe MR at 9 months, whereas older age was the only predictor of worsening MR.

Conclusions

Among patients with HF undergoing GRMT optimization, ACEi/ARB up-titration and HFpEF were associated with MR improvement, and the presence of moderate-severe MR after GRMT was associated with worse outcome.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s00392-022-01991-7.

2-Year Outcomes of Transcatheter Mitral Valve Replacement in Patients With Severe Symptomatic Mitral Regurgitation

BACKGROUND

Transcatheter mitral valve replacement (TMVR) is feasible for selected patients with severe mitral regurgitation (MR) who are poor candidates for valve surgery. Intermediate-term to long-term TMVR outcomes have not been reported.

OBJECTIVES

This study sought to evaluate the safety and effectiveness through 2-year follow-up of TMVR in high-surgical-risk patients with severe MR.

METHODS

The first 100 patients enrolled in the Expanded Clinical Study of the Tendyne Mitral Valve System, an open-label, nonrandomized, prospective study of transapical TMVR, were followed for 2 years.

RESULTS

The patients (aged 74.7 ± 8.0 years, 69.0% male) had symptomatic (66.0% New York Heart Association [NYHA] functional class III or IV) grade 3+ or 4+ MR that was secondary or mixed in 89 (89.0%). Prostheses were successfully implanted in 97 (97.0%) patients. At 2 years, all-cause mortality was 39.0%; 17 (43.6%) of 39 deaths occurred during the first 90 days. Heart failure hospitalization (HFH) fell from 1.30 events per year preprocedure to 0.51 per year in the 2 years post-TMVR (P < 0.0001). At 2 years, 93.2% of surviving patients had no MR. No patient had >1+ MR. The improvement in symptoms at 1 year (88.5% NYHA functional class I or II) was sustained to 2 years (81.6% NYHA functional class I or II). Among survivors, the left ventricular ejection fraction was 45.6 ± 9.4% at baseline and 39.8 ± 9.5% at 2 years (P = 0.0012). Estimated right ventricular systolic pressure decreased from 47.6 ± 8.6 mm Hg to 32.5 ± 10.4 mm Hg (P < 0.005).

CONCLUSIONS

In this study, the impact of TMVR on severity of MR, reduction in HFH rate, and improvement in symptoms was sustained through 2 years. All-cause mortality and the need for HFH was highest in the first 3 months postprocedure. (Expanded Clinical Study of the Tendyne Mitral Valve System; NCT02321514).

Effect of oral tolvaptan for 1 year in patients with functional mitral regurgitation

The effect of the oral selective vasopressin V2-receptor antagonist tolvaptan for chronic phase therapy on patients with FMR remains unclear. We aimed to determine the efficacy of oral tolvaptan in patients with significant functional mitral regurgitation (FMR) to reduce the mortality and rehospitalization due to worsening heart failure (HF). We enrolled 219 patients (mean age 76 ± 9 years, 59.4% men) who were admitted at our hospital due to congestive HF during different two 1-year periods. The patients were divided into 2 groups: those who had significant FMR (MR ≥ grade 2 [n = 76]) and those who did not (MR < grade 2 [n = 143]) at discharge. The patients were further divided into a study group that received tolvaptan during follow-up and a control group that did not receive tolvaptan. We used an inverse probability of treatment weighting method with the primary end point defined as overall all-cause mortality and rehospitalization due to worsening HF within 1 year. Of the 76 patients with significant FMR at discharge, 2 of 20 (10%) who were administered tolvaptan died and 8 (40%) were readmitted to a hospital. Of the 56 patients who did not receive tolvaptan, 2 (3.5%) died and 18 (27.5%) required rehospitalization. After multiple adjustments, there were no significant differences for overall survival and rehospitalization between the groups (log-rank p = 0.700 and 0.510, respectively). Our results suggest that oral tolvaptan administration in addition to conventional diuretics had less impact on outcomes in patients with significant FMR.

Revisiting the Role of Guideline-Directed Medical Therapy for Patients with Heart Failure and Severe Functional Mitral Regurgitation

Patients with heart failure often have mitral regurgitation, which can generate a vicious cycle. Medical therapy remains the cornerstone of their treatment in this setting. This review revisits the role of medical therapy and its optimization for severe functional mitral regurgitation in the contemporary era.

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.

Treatment of Secondary Mitral Regurgitation in Heart Failure: A Shifting Paradigm in the Wake of the COAPT Trial

Secondary mitral regurgitation (MR) is common in patients with left heart dysfunction and it is associated with poor outcomes. Findings from the Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients with Functional Mitral Regurgitation (COAPT) trial, published in 2018, suggest that in a subset of people with heart failure with secondary MR that persists despite optimization of guideline-directed medical therapies, there is now a role for percutaneous mitral valve repair using the MitraClip device. Defining which patients are most likely to benefit from MitraClip, and when, requires both a multidisciplinary approach centered on heart failure, as well as a recognition of the need for further research in this area.

Treatment options for ischemic mitral regurgitation: A meta-analysis

BACKGROUND

Treatment of ischemic mitral regurgitation (IMR) is in evolution, as percutaneous procedures and complex surgical repair have been recently investigated in randomized clinical trials and matched studies. This study aims to review and compare the current treatment options for IMR.

METHODS

A comprehensive literature search was conducted using electronic databases. The primary outcome was all-cause long-term mortality. The secondary outcomes were perioperative mortality, unplanned rehospitalization, reoperation, and composite end points as defined in the original articles.

RESULTS

A total of 12 articles met the inclusion criteria and were included in the final meta-analysis. The MitraClip procedure did not confer a significant benefit in mortality and repeated hospitalization compared with medical therapy alone. In patients with moderate IMR, the adjunct of mitral procedure over coronary artery bypass graft is not associated with clinical improvements. When evaluating mitral valve (MV) replacement versus repair, hospital mortality was greater among patients undergoing replacement (odds ratio [OR], 1.91; P = .009), but both reoperation and readmission rates were lower (OR, 0.60, P = .05; and OR, 0.45, P < .02, respectively). Comparing restrictive annuloplasty alone with adjunctive subvalvular repair, subvalvular procedures resulted in fewer readmissions (OR, 0.50; P = .06) and adverse composite end points (P = .009).

CONCLUSIONS

MitraClip procedure is not associated with improved outcomes compared with medical therapy. MV replacement is associated with increased early mortality but reduced reoperation rate and readmission rate compared with MV repair using annuloplasty in moderate-to-severe IMR. Despite no significant benefit in isolated outcomes comparing annular and adjunct subvalvular procedures, the adjunct of subvalvular procedures reduces the risk of major postoperative adverse events.

Mitral regurgitation: lessons learned from COAPT and MITRA-Fr

Recent studies about percutaneous treatment of secondary mitral regurgitation (MR) underlined the importance of left ventricular geometry and features of mitral valve as determinants of procedural and long-term success. Guideline-directed medical therapy (GDMT), transcatheter mitral valve treatment (TMVT) and surgical procedures (mitral valve replacement, mitral valve repair at level of the annulus or subvalvular apparatus) have been extensively evaluated but not adequately compared in current clinical studies. A detailed analysis of the results of the study about transcatheter mitral valve repair would allow to evaluate the safety and effectiveness of such procedure and would provide potential indications for improving the quality of percutaneous and surgical repair in patients with moderate-to-severe secondary MR. Patients with proportionate MR (i.e., MR severity is proportional to the amount of left ventricular dilatation) are prone to respond to the optimization of medical therapy, while patients with disproportionate MR (i.e., MR severity is disproportionately higher than predicted by left ventricular dilatation, with high EROA and small left ventricle) are likely to benefit from additional repair. The identification of specific subpopulation of "high responders", based on the anatomic characteristics of the mitral valve and the relative dimensions of the annulus, the regurgitation and the left ventricle, can also apply to medical therapy. However, some pivotal component of MR (such as the symmetry of tethering and the differences in biomechanical features of leaflets) are not adequately investigated in current studies and warrant further evaluation.

Contrasting Effects of Pharmacological, Procedural, and Surgical Interventions on Proportionate and Disproportionate Functional Mitral Regurgitation in Chronic Heart Failure

Two distinct pathways can lead to functional mitral regurgitation (MR) in patients with chronic heart failure and a reduced ejection fraction. When remodeling and enlargement of the left ventricle (LV) cause annular dilatation and tethering of the mitral valve leaflets, there is a linear relationship between LV end-diastolic volume and the effective regurgitant orifice area of the mitral valve. These patients, designated as having proportionate MR, respond favorably to treatments that lead to reversal of LV remodeling and a decrease in LV volumes (eg, neurohormonal antagonists and LV assist devices), but they may not benefit from interventions that are directed only at the mitral valve leaflets (eg, transcatheter mitral valve repair). In contrast, when ventricular dyssynchrony causes functional MR attributable to unequal contraction of the papillary muscles, the magnitude of regurgitation is greater than that predicted by LV volumes. These patients, designated as having severe but disproportionate MR, respond favorably to treatments that are directed to the mitral valve leaflets or their supporting structures (eg, cardiac resynchronization or transcatheter mitral valve repair), but they may derive little benefit from interventions that act only to reduce LV cavity size (eg, pharmacological treatments). This novel conceptual framework reflects the important interplay between LV geometry and mitral valve function in determining the clinical presentation of patients, and it allows characterization of the determinants of functional MR to guide the most appropriate therapy in the clinical setting.

The Role of Arterial Hypertension in Mitral Valve Regurgitation

PURPOSE OF REVIEW

To review medical literature for evidence of association between hypertension and mitral regurgitation (MR) and summarize potential favorable effects of antihypertensive drugs on MR natural history and treatment.

RECENT FINDINGS

Hypertension and MR are common diseases affecting a large proportion of the general population. Contemporary evidence suggests that hypertension may worsen the progression and prognosis of MR through augmented mechanical stress and increased regurgitation volume. Renin-angiotensin axis inhibitors, beta-blockers, and vasodilators have been tested in order to prevent or decrease primary or secondary MR. Although antihypertensive agents may improve hemodynamic parameters and left ventricular remodeling in primary MR, there is no strong evidence of benefit on clinical outcomes. On the other hand, a beneficial effect of these drugs on secondary MR is better established. Moreover, there are no studies evaluating a possible benefit of lower blood pressure targets in MR. Randomized controlled trials are warranted to elucidate the precise role of antihypertensive therapy on treatment of MR.

Secondary mitral regurgitation: percutaneous edge-to-edge repair on the cutting edge?

PURPOSE OF REVIEW

Secondary mitral regurgitation commonly complicates heart failure. Although the evidence for its management is most robust for treating the underlying cardiomyopathy, treatment aimed at additionally reducing the severity of mitral regurgitation with a percutaneous edge-to-edge device, MitraClip, has recently emerged.

RECENT FINDINGS

Despite the use of contemporary evidence-based heart failure therapies, patients with secondary mitral regurgitation and heart failure continue to remain at high risk for adverse clinical events; in both the MITRA-FR and COAPT trials, an extremely high event rate was evident in the medically managed arms over the respective 12-24-month follow-up. Data supporting the use of MitraClip to mitigate adverse outcomes in secondary mitral regurgitation is, however, conflicting. In MITRA-FR no difference was noted between MitraClip compared with the medically managed arm for the composite of all-cause death or heart failure hospitalization at 12 months. However, in COAPT, a significant reduction in the rate of heart failure re-hospitalization over 2 years was evident with MitraClip compared with medical therapy alone.

SUMMARY

Recommendations exist for the use of MitraClip in patients with primary mitral regurgitation and prohibitive surgical risk. However, with the divergent results of two recent high-quality randomized trials, its role in patients with secondary mitral regurgitation remains controversial.

Kallikrein-Kinin System Suppresses Type I Interferon Responses: A Novel Pathway of Interferon Regulation

The Kallikrein–Kinin System (KKS), comprised of kallikreins (klks), bradykinins (BKs) angiotensin-converting enzyme (ACE), and many other molecules, regulates a number of physiological processes, including inflammation, coagulation, angiogenesis, and control of blood pressure. In this report, we show that KKS regulates Type I IFN responses, thought to be important in lupus pathogenesis. We used CpG (TLR9 ligand), R848 (TLR7 ligand), or recombinant IFN-α to induce interferon-stimulated genes (ISGs) and proteins, and observed that this response was markedly diminished by BKs, klk1 (tissue kallikrein), or captopril (an ACE inhibitor). BKs significantly decreased the ISGs induced by TLRs in vitro and in vivo (in normal and lupus-prone mice), and in human PBMCs, especially the induction of Irf7 gene (p < 0.05), the master regulator of Type I IFNs. ISGs induced by IFN-α were also suppressed by the KKS. MHC Class I upregulation, a classic response to Type I IFNs, was reduced by BKs in murine dendritic cells (DCs). BKs decreased phosphorylation of STAT2 molecules that mediate IFN signaling. Among the secreted pro-inflammatory cytokines/chemokines analyzed (IL-6, IL12p70, and CXCL10), the strongest suppressive effect was on CXCL10, a highly Type I IFN-dependent cytokine, upon CpG stimulation, both in normal and lupus-prone DCs. klks that break down into BKs, also suppressed CpG-induced ISGs in murine DCs. Captopril, a drug that inhibits ACE and increases BK, suppressed ISGs, both in mouse DCs and human PBMCs. The effects of BK were reversed with indomethacin (compound that inhibits production of PGE2), suggesting that BK suppression of IFN responses may be mediated via prostaglandins. These results highlight a novel regulatory mechanism in which members of the KKS control the Type I IFN response and suggest a role for modulators of IFNs in the pathogenesis of lupus and interferonopathies.

Percutaneous Mitral Valve Interventions and Heart Failure

Mitral regurgitation (MR) is the most frequent Valvular Heart Disease (VHD) and is an important cause of heart failure. MR can be caused by primary valve abnormality (Degenerative MR/Primary MR) or it can be secondary to cardiomyopathy (Functional MR/Secondary MR). Medical management alleviates symptoms but does not alter the progression of the disease. Current guidelines recommend surgery for moderate-to-severe (Grade > 3) MR in patients with symptoms or evidence of left ventricular dysfunction. Despite current practice guidelines, the majority of patients with severe MR do not undergo surgery. The reasons include high surgical risk from advanced age or multiple comorbidities, and a lack of clear data supporting valve surgery for secondary MR with LV dysfunction. The recent emergence of percutaneous interventional approaches in treating MR has expanded therapeutic options for patients who are at high risk for conventional Mitral Valve (MV) surgery. In this chapter, we will review the novel advancements in the field of percutaneous MV interventions that could potentially become the standard of care for patients with MR and heart failure.

Renin-angiotensin system inhibitors in patients with or without ischaemic mitral regurgitation after acute myocardial infarction

Objective

Little is known about the long-term effects of renin–angiotensin system inhibitors (RASI) on cardiovascular events in patients after acute myocardial infarction (AMI) with ischaemic mitral regurgitation (IMR). The purpose of this study was to investigate the association of RASI with the incidence of adverse cardiac events in patients with or without IMR after AMI.

Methods

We reviewed charts of 1208 consecutive patients admitted with AMI who underwent emergency coronary angiography between 2000 and 2012. After excluding patients who died within 30 days, 551 patients were diagnosed to have mild or greater MR by transthoracic echocardiography (patients with IMR); the remaining 505 patients had no or trivial MR (non-IMR patients).

Results

Of the study patients, 395 (72%) patients with IMR and 403 (80%) non-IMR patients received RASI. Survival analysis showed that freedom from cardiac death and the composite of cardiac death and heart failure (HF) was significantly higher in patients with IMR receiving RASI than in those not receiving RASI (P<0.001 and P<0.001, respectively). Moreover, adjusted survival analysis using the inverse probability treatment weighting method showed a significant association of RASI therapy with reduced cardiac death (P=0.010) and the composite of cardiac death and HF (P=0.044) in patients with IMR. However, in non-IMR patients, there were no significant associations between RASI therapy and the outcome measures.

Conclusions

RASI therapy was associated with a lower incidence of adverse cardiac events in patients with IMR after AMI, but not in patients without IMR.

Functional Mitral Regurgitation: Appraising the Evidence Behind Recommended Treatment Strategies

Functional mitral regurgitation (MR) is the most common type of MR encountered in clinical practice. Because the disease arises from the ventricular aspect of the mitral valve apparatus, treatment therapies are less defined and outcomes are poor. In this review, the state of evidence for medical and surgical therapy in functional MR is appraised. Future directions for research in this area are also defined.

Comparison of the Efficacy and Safety of Different ACE Inhibitors in Patients With Chronic Heart Failure: A PRISMA-Compliant Network Meta-Analysis

Heart failure is a public health problem and a great economic burden for patients and healthcare systems. Suppression of the renin-angiotensin system (RAS) by angiotensin-converting enzyme (ACE)-inhibitors remains the mainstay of treatment for heart failure. However, the abundance of ACE inhibitors makes it difficult for doctors to choose.We performed this network meta-analysis of ACEIs in patients with heart failure in order to address this area of uncertainty.We searched PubMed, Embase, CENTRAL, and Medline.Any randomized controlled trial evaluating the efficacy and safety of captopril, enalapril, lisinopril, ramipril, or trandolapril or combined interventions of 2 or more of these drugs.Two reviewers extracted the data and made the quality assessment. At first, we used Stata software (version 12.0, StataCorp, College Station, TX) to make traditional pairwise meta-analyses for studies that directly compared different interventions. Then, network meta-analysis was performed using WinBUGS (version 1.4.3, MRC Biostatistics Unit, Cambridge, UK).A total of 29 studies were included. Lisinopril was associated with a higher rate of all-cause mortality compared with placebo (odds ratio 65.9, 95% credible interval 1.91 to 239.6) or ramipril (14.65, 1.23 to 49.5). Enalapril significantly reduced systolic blood pressure when compared with placebo (standardized mean differences -0.6, 95% credible interval -1.03 to -0.18). Both captopril (odds ratio 76.2, 95% credible interval 1.56 to 149.3) and enalapril (274.4, 2.4 to 512.9) were associated with a higher incidence of cough compared to placebo.Some important outcomes such as rehospitalization and cardiac death were not included. The sample size and the number of studies were limited, especially for ramipril.Our results suggest that enalapril might be the best option when considering factors such as increased ejection fraction, stroke volume, and decreased mean arterial pressure. However, enalapril was associated with the highest incidence of cough, gastrointestinal discomfort, and greater deterioration in renal function. Trandolapril ranked first in reducing systolic and diastolic blood pressure. Ramipril was associated with the lowest incidence of all-cause mortality. Lisinopril was the least effective in lowering systolic and diastolic blood pressure and was associated with the highest incidence of all-cause mortality.

The MitraClip and survival in patients with mitral regurgitation at high risk for surgery: A propensity-matched comparison

BACKGROUND

We compared 30-day and 1-year survival among high-risk mitral regurgitation (MR) patients treated with the MitraClip (Abbott Vascular, Abbott Park, IL) with matched non-surgically treated patients from the Duke Echocardiography Laboratory Database (DELD).

METHODS AND RESULTS

High-risk patients with 3+/4+ MR managed non-surgically between years 2000 and 2010 in the longitudinal DELD were matched to high-risk MitraClip patients. Patient matching was performed using the method of nearest available Mahalanobis distance metric within calipers defined by the propensity score. Kaplan-Meier estimates and stratified Cox proportional hazards models were used to compare survival at 30 days and 1 year. Among 953 high-risk DELD patients available for matching, 30-day and 1-year mortality were 6.5% and 26.2%. Close matches were obtained for 239 of the 351 MitraClip patients. The 30-day mortality in MitraClip patients was lower (4.2%) when compared with matched DELD patients (7.2%). The 1-year relative risk of mortality of the MitraClip compared with non-surgical treatment was 0.64 (95% CI 0.45-0.91; log-rank P = .013). These results in favor of the MitraClip remained significant upon further adjustment for baseline differences between groups (P = .043).

CONCLUSIONS

This matched comparison of severe MR patients at high surgical risk supports the safety of the MitraClip relative to medical therapy at 30 days and a survival benefit at 1 year.

Comparative effectiveness of Mitraclip plus medical therapy versus medical therapy alone in high-risk surgical patients: a comprehensive review

In recent years, Mitraclip has become available as a treatment option for mitral regurgitation in high-risk surgical patients. Focusing on the incremental effectiveness of Mitraclip versus the current standard of care, this article provides a comparative review of the evidence on Mitraclip and standard medical therapy (MT) in high-risk mitral regurgitation patients. Evidence was retrieved from seven major databases. Results suggest that Mitraclip presents a high safety profile and a good middle-term effectiveness performance. Evidence on long-term effectiveness is limited both for Mitraclip and MT. Few studies allow a comparison with MT and comparative results on different endpoints are mixed. Therefore, the available evidence does not conclusively inform whether or under which circumstances Mitraclip should be preferred over MT in the treatment of high-risk patients. Head-to-head real-world studies would be needed, as they would provide great and timely insights to support policy decisions when medical devices are at stake.

Early improvement of functional mitral regurgitation in patients with idiopathic dilated cardiomyopathy

The aim of the study was to assess the clinical and prognostic impact of early functional mitral regurgitation (FMR) improvement on the outcome of patients with idiopathic dilated cardiomyopathy (IDC). The prevalence and prognostic role of FMR improvement, particularly at early follow-up, in patients with IDC are still unclear. From 1988 to 2009, we enrolled 470 patients with IDC with available FMR data at baseline and after 6 ± 2 months. According to the evolution of FMR, patients were classified into 3 groups: stable absent-mild FMR, early FMR improvement (downgrading from moderate-severe to absent-mild), and persistence/early development of moderate-severe FMR. At baseline, 177 of 470 patients (38%) had moderate-severe FMR. Patients with early FMR improvement had significantly better survival rate-free from heart transplant with respect to those with persistence/early development of moderate-severe FMR (93%, 81%, and 66% vs 91%, 64%, and 52% at 1, 6, and 12 years, respectively; p = 0.044). At 6-month follow-up multivariate analysis, FMR improvement was associated with better prognosis (hazard ratio 0.78, 95% confidence interval [CI] 0.64 to 0.96, p = 0.02); the other independent predictors were male gender, heart failure duration, and early re-evaluation of the New York Heart Association class and left ventricle systolic function. This model provided more accurate risk stratification compared with the baseline model (Net Reclassification Index 80% at 12 months and 41% at 72 months). In conclusion, in a large cohort of patients with IDC receiving optimal medical treatment, early improvement of FMR was frequent (53%) and emerged as a favorable independent prognostic factor with an incremental short- and long-term power compared with the baseline evaluation.

Secondary Mitral Regurgitation in Heart Failure with Reduced or Preserved Left Ventricular Ejection Fraction

Secondary mitral regurgitation (MR) has been extensively studied in heart failure due to reduced ejection fraction. In contrast, the occurrence and the pathogenesis of secondary MR are much less known in heart failure with preserved ejection fraction (HFpEF). The present review aimed at describing this common but ignored feature of HFpEF.

Mitral valve regurgitation and left ventricular systolic dysfunction: corrective surgery or cardiac resynchronization therapy?

Mitral regurgitation (MR) can be found in a sizeable percentage of patients with chronic congestive heart failure (CHF) and systolic left ventricular (LV) dysfunction despite a structurally normal valve. This functional or secondary regurgitation results from a dysbalance between closing and opening forces on the mitral leaflets due to reduced LV contractility, geometric distortion of the subvalvular apparatus, and global dilatation of the left ventricle and the mitral annulus. MR in LV dysfunction has a negative impact on both symptoms and prognosis. Surgical correction of secondary MR remained controversial although it was found to be technically feasible and to provide symptomatic benefit in some (mostly) mono-center series. Cardiac resynchronization therapy (CRT) was also found to improve secondary mitral regurgitation. However, the prediction in which patient significant secondary MR will improve with CRT is largely unresolved. The following paper reviews the available data concerning the two major interventional options for significant secondary MR in patients with CHF and systolic LV dysfunction, i.e. mitral valve surgery vs. CRT, and describes our institutional approach to this problem.

Exercise does not enhance the prognostic value of Doppler echocardiography in patients with left ventricular systolic dysfunction and functional mitral regurgitation at rest

BACKGROUND

Functional mitral regurgitation (MR) is a powerful predictor of poor prognosis in patients with chronic heart failure (CHF) due to left ventricular systolic dysfunction (LVSD). However, severity of MR varies with dynamic exercise. Accordingly, we sought to assess the prognostic value of exercise-induced changes in functional MR in patients with LVSD and functional MR at rest.

METHODS

One hundred four patients with chronic heart failure due to LVSD (ejection fraction [EF] < 45%) and functional MR at rest underwent conventional continuous 2-dimensional Doppler echocardiography at rest and during maximal symptom-limited exercise. The primary end point of the study was all-cause mortality. The median follow-up period was 20 months.

RESULTS

Fifty-six patients (54%) had ischemic cardiomyopathy. When feasible, all 56 patients with ischemic cardiomyopathy had undergone revascularization procedures before enrollment into the study. In the whole patient cohort, resting LV end-diastolic volume was 205 +/- 76 mL and EF was 26% +/- 9%. Univariate predictors of death were functional class (New York Heart Association), LV EF, LV end-diastolic volume, resting mitral effective regurgitant orifice, mitral E deceleration time, tricuspid annular plane systolic excursion < or = 14 mm, systolic blood pressure, LV EF, and trans-tricuspid pressure gradient response to exercise. Exercise-induced change in mitral effective regurgitant orifice did not predict survival (HR 0.99, 95% CI 0.94-1.04, P = .63). By Cox multivariate analysis, resting LV end-diastolic volume and tricuspid annular plane systolic excursion < or = 14 mm were the independent predictors of death.

CONCLUSIONS

Exercise Doppler echocardiography does not refine the predictive value of resting Doppler echocardiography in patients with LVSD and functional MR at rest.

The frequency, impact, and management of mitral regurgitation in patients with heart failure

Management of severe chronic mitral regurgitation (MR) in severe heart failure is challenging. There are controversies over the efficacy of surgical correction of MR in the presence of severely depressed left ventricular (LV) function. The etiology of MR plays an important role in clinical decision making. In organic MR, surgical correction should be performed even if patients have an LV ejection fraction of less than or equal to 30%. In functional MR, treatment of myocardial damage should be considered as the priority. The long-term mortality benefit of surgical correction of functional MR associated with severe LV dysfunction caused by cardiomyopathy (ischemic or dilated) likely depends on whether myocardial dysfunction can be reversed or improved by treatments (eg, coronary artery revascularization, pharmacologic treatment). Preoperative examination of viable myocardium (ischemic and hibernating myocardium) helps to identify a surgical candidate with ischemic MR associated with ischemic cardiomyopathy. The role of device treatment of MR in heart failure needs further investigation with outcome data.

Intraventricular dyssynchrony may play a role in the development of mitral regurgitation in dilated cardiomyopathy

BACKGROUND

The development of functional mitral regurgitation (MR) in dilated cardiomyopathy (DCM) has been attributed to altered left ventricular (LV) geometry and annular dilatation. We propose the hypothesis that intraventricular dyssynchrony may play a role in the development of MR in DCM.

METHODS AND RESULTS

Tissue Doppler echocardiography was performed in 32 DCM patients to assess the time from the onset of the QRS complex to the peak systolic myocardial strain (Ts) at 2 segments adjacent to the anterolateral and posteromedial papillary muscles from a short axis view. The time difference corrected by the RR interval (DeltaTs/ radicalRR) was used to evaluate dyssynchrony of these segments. There was no difference in the QRS duration (103 +/- 29 ms versus 95 +/- 22 ms, P = .38) or the presence of left bundle branch block (39% versus 14 %, P = .25) between 18 patients with MR and 14 patients without MR. However, DeltaTs/ radicalRR was significantly increased in the patients with MR, compared with those without MR (104 +/- 67 ms versus 5 +/- 16 ms, P < .0001). Stepwise multiple regression analysis showed that DeltaTs/ radicalRR was independent contributing factor of MR.

CONCLUSION

Dyssynchrony of myocardial segments adjacent to the papillary muscles may disturb synchronized closure of the mitral leaflets and cause MR in DCM.

Drugs for left ventricular remodeling in heart failure

Left ventricular (LV) remodeling (ie, enlargement and functional deterioration occurring over time) is among the main mechanisms of progression in heart failure (HF). LV dilatation and dysfunction are major negative prognostic markers in patients with HF. Treatments that are effective in limiting or even reversing this process can be expected to provide clinical benefit. Changes in LV dimensions rather than in ejection fraction should be used to monitor remodeling. Ejection fraction can be influenced by transient loading conditions and by agents that stimulate contractility at the expense of increased oxygen demand, whereas dimensional changes probably reflect structural modifications occurring in the myocardium. The neurohormonal antagonists that have been demonstrated to reduce mortality and morbidity in HF (angiotensin-converting enzyme inhibitors [ACE], beta-blockers, angiotensin receptor blockers, and aldosterone antagonists) are also able to inhibit or reverse remodeling. In reverse remodeling, beta-blockers appear to be superior to the other classes of drugs, with a stronger correlation between dose and effect, but it must be remembered that they have been tested as an addition to background therapy that may include ACE inhibitors. With regard to nonpharmacologic strategies, biventricular pacing is associated with functional improvement and reverse remodeling in patients with advanced HF and electromechanical dyssynchrony, and it recently has been demonstrated to improve survival in a randomized clinical trial.

Activity questionnaires; a useful tool in accessing heart failure patients

AIM

The aim of the study was to correlate the score derived from Specific Activity Questionnaire (SAQ), Left Ventricular Dysfunction 36 (LVD 36) and the Minnesota Living with Heart Failure Questionnaire (LIhFE) with peak oxygen consumption measured during maximal treadmill exercise spirometry in patients with heart failure.

METHODS

We prospectively studied 106 patients, average age 47+/-15.5 (mean+/-SD), with symptomatic heart failure. All were asked to answer the questions of the above mentioned questionnaires. Subsequently patients underwent treadmill exercise spirometry to measure peak oxygen consumption (VO2 peak ml/kg/min) using the Dargie protocol and to derive functional class according to the Weber classification system.

RESULTS

SAQ had a very high performance in classifying patients with a VO2 peak <20 ml/kg/min and those with a VO2 peak <14 ml/kg/min. The correlation between VO2 peak achieved and the METs corresponding to the score derived from SAQ according to the given answers was r=0.77 (p<0.01). The correlation between VO2 peak achieved and the score from LVD 36 was r=-0.74 (p<0.01). The correlation between VO2 peak achieved and the score from LIhFE was r=-0.71 (p<0.01).

CONCLUSION

The Specific Activity Questionnaire, the Left Ventricular Dysfunction and the Minnesota Living with Heart Failure Questionnaire were used to predict aerobic capacity and all correlated significantly with peak VO2 achieved from exercise spirometry. The above questionnaires represent a useful method to access heart failure patients and are valuable for those unable to undergo a treadmill test.

Quantification of annular dilatation and papillary muscle separation in functional mitral regurgitation: role of anterior mitral leaflet length as reference

BACKGROUND

We hypothesized that anterior mitral leaflet length (ALL) does not differ significantly between normal subjects and patients with functional mitral regurgitation (FMR) and hence may be used as a reference measurement to quantify annular dilatation and papillary muscle separation.

METHODS AND RESULTS

We prospectively studied 50 controls, 15 patients with systolic left ventricular dysfunction (LVD) with significant FMR, and 15 patients with LVD without significant FMR. Significant MR was defined as an effective regurgitant orifice area > or = 0.2 cm2 as measured by the flow convergence method. Annular diameter, interpapillary distance, and ALL were measured, and the following ratios were derived: annular diameter indexed to ALL (ADI) and interpapillary distance indexed to ALL (IPDI). There was no significant difference in ALL among the three groups. The mean ADI was 1.26 times controls in patients with LVD without significant FMR compared to 1.33 times controls in patients with LVD with significant FMR (P = 0.06, no significant difference between groups). The mean IPDI was 1.42 times controls in patients with LVD without significant FMR compared to 2.1 times controls in patients with LVD with significant FMR (P < 0.0001, significant difference between groups).

CONCLUSION

There was no significant difference in ALL between controls and patients with LVD. ALL can be used as a reference measurement to quantify annular dilatation and papillary muscle separation in patients with FMR. Interpapillary distance but not annular diameter indexed to ALL correlates with severity of FMR.

Contribution of exercise-induced mitral regurgitation to exercise stroke volume and exercise capacity in patients with left ventricular systolic dysfunction

BACKGROUND

Functional mitral regurgitation (MR) is common in patients with heart failure and left ventricular (LV) dysfunction, and its severity may vary over time, depending primarily on the loading conditions. Because dynamic changes in the severity of functional MR may affect forward stroke volume, we hypothesized that exercise-induced changes in MR severity influence the stroke volume response of patients with LV dysfunction to exercise, and hence their exercise capacity.

METHODS AND RESULTS

Heart failure patients (n=25; mean age 53+/-12 years) with LV dysfunction underwent dynamic bicycle exercise at steady-state levels of 30%, 60%, and 90% of predetermined peak VO2. During each exercise level, right heart pressures, cardiac output, VO2, and MR severity were measured simultaneously. During exercise, MR severity, as evaluated by the ratio of MR jet over left atrium area, increased from 15+/-8% to 33+/-15%. Peak VO2, exercise-induced changes in stroke volume, and those in capillary wedge pressure correlated with the changes in MR (r=-0.55, -0.87, and 0.62, respectively, P<0.01). The changes in MR severity also correlated with those in end-diastolic (r=-0.75, P<0.01) and end-systolic (r=-0.72, P<0.01) sphericity indexes and those in the coaptation distance (r=0.86, P<0.01).

CONCLUSIONS

Our data indicate that in patients with LV dysfunction, exercise-induced changes in MR severity limit the stroke volume adaptation during exercise and therefore contribute to limitation of exercise capacity.

Effect of losartan on degree of mitral regurgitation quantified by echocardiography

The objective of this study was to determine the effect of oral losartan on the degree of mitral regurgitation (MR). The regurgitant volume and effective regurgitant orifice were quantified using 3 methods (flow convergence, quantitative Doppler, and quantitative 2-dimensional echocardiography) in 32 patients (26 men, mean age 67 +/- 14 years) with MR, both at baseline and 4 hours after losartan (50 mg orally). Twenty-eight patients were also reevaluated after 1 month of continued treatment with losartan (50 mg/day). With treatment, systolic blood pressure decreased from 143 +/- 16 to 130 +/- 18 mm Hg and left ventricular end-systolic wall stress from 173 +/- 46 to 156 +/- 44 g/cm2 (both p < 0.001). With treatment, regurgitant volume decreased (from 77 +/- 28 to 64 +/- 26 ml, - 18 +/- 10%; p < 0.001) in direct relation to the effective regurgitant orifice change (from 43 +/- 16 to 37 +/- 15 mm2, -17 +/- 10%; p < 0.001) but without significant change in regurgitant gradient or duration. Wide individual variability in response was observed unrelated to the magnitude of blood pressure changes. Larger reduction in regurgitant volume was observed in patients with a marked decrease in wall stress (r = 0.47, p = 0.01) and higher baseline end-diastolic volume index (r = -0.38, p = 0.03) and regurgitant volume (r = -0.45, p = 0.01). Acute improvements were sustained and unchanged at 1 month (all p > 0.15). Treatment of MR using the angiotensin receptor antagonist losartan produces a significant and sustained decrease in the degree of MR, with decreases in regurgitant volume and effective regurgitant orifice. However, the changes are of modest and variable magnitude.