Ischemic mitral regurgitation: long-term outcome and prognostic implications with quantitative Doppler assessment

Clinical Characteristics and Long-Term Prognosis of Elderly Valvular Heart Disease Patients with Diabetes Mellitus: Five-Year Experience from a Single-Center Study of Southern China

Background

Diabetes mellitus (DM) is a prognostic marker in elderly patients with cardiovascular diseases, but its predictive value in elderly valvular heart disease (VHD) patients is unclear. This study aimed to investigate the effect of DM on the long-term outcome of elderly VHD patients.

Methods

This single-center, observational study enrolled patients aged 65 and older consecutively with confirmed VHD using echocardiography. Patients, divided into the DM group and non-DM group, were followed up for major adverse cardiac and cerebrovascular events (MACCEs), including all-cause death, ischemic stroke, and heart failure rehospitalization.

Results

Our study consisted of 532 patients over a median follow-up of 52.9 months. Compared with the non-DM group (n = 377), the DM group (n = 155) had higher incidences of ischemic stroke (25.2% vs. 13.5%, P=0.001), heart failure rehospitalization (37.4% vs. 20.7%, P < 0.001), and MACCEs (60.0% vs. 35.8%, P < 0.001). After adjustment of confounders by the multivariable cox regression, DM appeared as an independent predictor for MACCEs (adjusted hazard ratio, aHR: 1.88; 95% confidence interval 1.42–2.48; P < 0.001). In the subgroup analysis of VHD etiology and functional style, conversely, DM was a protective factor for MACCEs in the patients with rheumatic VHD compared with those without rheumatic VHD (aHR: 0.43 vs. 2.27, P=0.004).

Conclusions

DM was an independent predictor for ischemic stroke and heart failure rehospitalization in elderly VHD patients undergoing conservative treatment.

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.

Mitral Regurgitation Following Acute Myocardial Infarction Treated by Percutaneous Coronary Intervention-Prevalence, Risk factors, and Predictors of Outcome

Mitral regurgitation (MR) following acute myocardial infarction (AMI) worsens prognosis and reports of prevalence vary significantly. The objective was to determine prevalence, risk factors, and outcomes related to MR following AMI. We identified 1000 consecutive patients admitted with AMI in 2016/17 treated by percutaneous coronary intervention with pre-discharge transthoracic echocardiography. MR was observed in 294 of 1000 (29%), graded as mild (n = 224 [76%]), moderate (n = 61 [21%]) and severe (n = 9 [3%]). Compared with patients without MR, patients with MR were older (70 ± 12 vs 63 ± 13 years; p <0.001), with worse left ventricular ejection fraction (LVEF) (52 ± 15% vs 55 ± 11%; p <0.001) and creatinine clearance (69 ± 33 ml/min vs 90 ± 39 ml/min; p <0.001). They also had higher rates of hypertension (64% vs 55%; p = 0.012), heart failure (3.4% vs 1.1%; p = 0.014), previous MI (28% vs 20%; p = 0.005) and severe flow-limitation in the circumflex (50% vs 33%; p <0.001) or right coronary artery (51% vs 42%; p = 0.014). Prevalence and severity of MR were unaffected by AMI subtype. Revascularization later than 72 hours from symptom-onset was associated with increased likelihood of MR (33% vs 25%; p = 0.036) in patients with non-ST elevation myocardial infarction (NSTEMI). After a mean of 3.2 years, 56 of 288 (19%) patients with untreated MR died. Age and LVEF independently predicted mortality. The presence of even mild MR was associated with increased mortality (p = 0.029), despite accounting for confounders. In conclusion, MR is observed in over one-quarter of patients after AMI and associated with lower survival, even when mild. Prevalence and severity are independent of MI subtype, but MR was more common with delayed revascularization following NSTEMI.

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.

Mitral and Tricuspid Valves Percutaneous Repair in Patients with Advanced Heart Failure: Panacea, or Pandora's Box?

In heart failure with reduced ejection fraction, the interventional landscape has recently expanded. New transcatheter approaches are emerging for both mitral and tricuspid secondary (functional) regurgitation. Transcatheter therapies for mitral and tricuspid valve require a more tailored approach than for the aortic valve, because of more heterogeneous clinical scenarios, anatomic features, and mechanisms of valvular lesions.

CMR predictors of secondary moderate to severe mitral regurgitation and its additive prognostic role in previous myocardial infarction

BACKGROUND

We aimed to determine predictors and the additive prognostic role of moderate to severe (MS) ischemic mitral regurgitation (MR) in myocardial infarction (MI).

METHODS

Four hundred twenty-two patients with previous MI underwent cardiac magnetic resonance (CMR) imaging for the assessment of left ventricular (LV) ejection fraction (EF), end-diastolic (EDV) and end-systolic volume (ESV), sphericity index, wall motion score index (WMSI), and late gadolinium enhancement (LGE). Echocardiography was performed to assess MR.

RESULTS

Thirty-eight had from moderate to severe MR (MS-MR group) and 384 did not (No MS-MR group). The S-MR group had higher LV volumes, sphericity index, WMSI, and LGE extent, and lower LVEF. At univariate logistic regression analysis, dilated volumes, SI >0.43, dyskinesia of inferolateral wall, papillary muscle (PM)-LGE, and LGE extent >16% were associated with MS-MR. At multivariate analysis, only SI (OR=5.7) and PM-LGE (OR=3) were independently associated with MS-MR. Considering only patients without LV dilatation, only dyskinesia in the inferolateral wall was a predictor of MS-MR (OR 34.8). Thirty cardiac events (cardiac death, appropriate implantable cardioverter-defibrillator firing, and resuscitated cardiac arrest) occurred during a median follow-up of 1,276 days. After adjusting the prognostic variables at univariate analysis by age (>65 years) and selecting those that were significant (EDV > 95 ml/m², ESV >53 ml/m², EF <30%, WMSI >1.65, LGE >12%, S-MR), only WMSI >1.65 and MS-MR remained an independent predictor of cardiac events.

CONCLUSIONS

Increased WMSI and PM-LGE in the overall population and inferolateral dyskinesia in patients without ESV dilatation are predictors of MS-MR; MS-MR and elevated WMSI have independent negative prognostic value.

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.

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.

Multiple percutaneous coronary interventions worsen outcomes for subsequent surgical correction of chronic ischemic mitral regurgitation

Objective

We investigated whether or not a history of multiple percutaneous coronary interventions (PCIs) is associated with clinical outcomes after surgery for ischemic mitral regurgitation.

Methods

A total of 309 patients with chronic ischemic mitral regurgitation and left ventricular ejection fraction ≤40% who underwent restrictive mitral annuloplasty were classified as follows: patients with no or 1 previous PCI (nonmultiple PCI group [n = 211]) and patients with 2 or more previous PCIs (multiple PCIs group [n = 98]). Mean follow-up duration was 53 ± 40 months.

Results

Before surgery, there were no intergroup differences in patient demographic characteristics except for lower estimated glomerular filtration rate in patients with multiple PCIs. These patients underwent concomitant coronary artery bypass grafting less frequently with a lower number of distal anastomoses (P < .05 for both). The 30-day mortality was 3.3% and 2.0% in the nonmultiple and multiple PCIs group, respectively (P = .72). During follow-up, there were 157 deaths. Patients with multiple PCIs showed lower 5-year survival rate (44% vs 64%; P = .002). After adjustments with inverse-probability-of-treatment weighting, multiple PCIs history was an independent risk factor for mortality (adjusted hazard ratio, 1.4; 95% confidential interval, 1.1-1.7; P = .002). Patients with multiple PCIs showed less improvement in left ventricular ejection fraction (interaction effect P < .001).

Conclusions

In patients with ischemic mitral regurgitation, a history of previous multiple PCIs was associated with increased risk of long-term postoperative mortality, with less improvement in left ventricular ejection fraction.

Integration of Functional Imaging, Cytometry, and Unbiased Proteomics Reveals New Features of Endothelial-to-Mesenchymal Transition in Ischemic Mitral Valve Regurgitation in Human Patients

Background: Following myocardial infarction, mitral regurgitation (MR) is a common complication. Previous animal studies demonstrated the association of endothelial-to-mesenchymal transition (EndMT) with mitral valve (MV) remodeling. Nevertheless, little is known about how MV tissue responds to ischemic heart changes in humans.

Methods: MVs were obtained by the Cardiothoracic Surgical Trials Network from 17 patients with ischemic mitral regurgitation (IMR). Echo-doppler imaging assessed MV function at time of resection. Cryosections of MVs were analyzed using a multi-faceted histology and immunofluorescence examination of cell populations. MVs were further analyzed using unbiased label-free proteomics. Echo-Doppler imaging, histo-cytometry measures and proteomic analysis were then integrated.

Results: MVs from patients with greater MR exhibited proteomic changes associated with proteolysis-, inflammatory- and oxidative stress-related processes compared to MVs with less MR. Cryosections of MVs from patients with IMR displayed activated valvular interstitial cells (aVICs) and double positive CD31+ αSMA+ cells, a hallmark of EndMT. Univariable and multivariable association with echocardiography measures revealed a positive correlation of MR severity with both cellular and geometric changes (e.g., aVICs, EndMT, leaflet thickness, leaflet tenting). Finally, proteomic changes associated with EndMT showed gene-ontology enrichment in vesicle-, inflammatory- and oxidative stress-related processes. This discovery approach indicated new candidate proteins associated with EndMT regulation in IMR.

Conclusion: We describe an atypical cellular composition and distinctive proteome of human MVs from patients with IMR, which highlighted new candidate proteins implicated in EndMT-related processes, associated with maladaptive MV fibrotic remodeling.

From secondary to tertiary mitral regurgitation: the paradigm shifts, but uncertainties remain

Secondary mitral regurgitation (MR) is the most common and undertreated form of MR, whose contribution to poor prognosis and indications to correction remains under discussion. MR has been characterized into 'proportionate' or 'disproportionate', based on left ventricle (LV) and regurgitant volumes, whereas 'tertiary' MR identifies conditions, in which regurgitation is pathologic per se and actively contributes to LV dysfunction. Echocardiographic and anatomo-pathological studies revealed that secondary MR prompts subtle leaflet maladaptive changes, actively contributing to the dynamic progression of secondary MR. We critically discuss the paradigm shift from secondary to tertiary MR and question the notion that MV leaflets play a passive role in secondary MR. We also review the role of standard transthoracic echocardiography for appraising and quantifying maladaptive MV leaflet changes and LV volumes and call for a more sophisticated and comprehensive imaging framework for classifying MR in future interventional studies.

Prognostic impact of transcatheter mitral valve repair in patients with exercise-induced secondary mitral regurgitation

AIMS

Although exercise-induced secondary mitral regurgitation (MR) is known to have a poor prognosis, the therapeutic strategy towards this condition remains to be investigated. In the present study, we aimed to investigate the prognostic impact of transcatheter mitral valve repair (TMVr) using the MitraClip in patients with exercise-induced secondary MR.

METHODS AND RESULTS

Of the 200 consecutive patients with secondary MR who underwent exercise stress echocardiography, 46 (23%) that presented with exercise-induced secondary MR [i.e. increase in effective regurgitant orifice area (EROA) of ≥ 0.13 cm2] were enrolled in the present investigation. The composite endpoints of all-cause mortality and hospitalization for heart failure were evaluated. Of the 46 patients included in the current cohort, 19 (41%) underwent TMVr and 27 (59%) were medically managed (control group). Although the TMVr group tended to present with a greater EROA at rest (0.26 ± 0.10 vs. 0.20 ± 0.08 cm2, P = 0.047), there were no differences in the EROA changes during exercise between the two groups (0.18 ± 0.10 vs. 0.18 ± 0.04 cm2, P = 0.940). While the TMVr group reported a higher event-free survival rate after the 13-month follow-up period (log-rank P = 0.017), the Cox proportional-hazard analysis suggested the TMVr to be associated with clinical outcomes (hazard ratio: 0.419, P = 0.044).

CONCLUSION

As opposed to the medical management, TMVr treatment was associated with a lower risk of composite endpoints in patients with exercise-induced secondary MR. Exercise stress echocardiography is considered to have played an important role in decision-making for secondary MR.

Long-term clinical and haemodynamic results after transcatheter annuloplasty for secondary mitral regurgitation

AIMS

The study sought to investigate the long-term outcome after transcatheter mitral valve annuloplasty for secondary mitral regurgitation (MR).

METHODS AND RESULTS

Consecutive patients with symptomatic secondary MR undergoing transcatheter mitral valve annuloplasty with the Carillon device at Leipzig University Hospital between 2012 and 2018 were studied prospectively. Left ventricular (LV) function and MR severity were quantified by standardized echocardiography. 33 patients were included. Mean age was 75 ± 10 years, and 20 patients were women. A Society of Thoracic Surgeons score of 8.1 ± 7.2% indicated high-risk status. In 24 patients, MR resulted from LV remodelling and dysfunction, eight suffered from left atrial dilatation, and one patient had MR due to combined primary and secondary aetiology. LV ejection fraction at baseline was (median) 38% [inter-quartile range (IQR) 30-49%]. During the mean follow-up time of 45 ± 20 months, 17 patients died, two patients withdraw consent, and four patients were lost. Of the remaining patients, four were hospitalized for decompensated heart failure. Two of these patients underwent additional transcatheter edge-to-edge mitral valve repair. At follow-up, New York Heart Association (NYHA) functional class improved from 95% in Class III/IV at baseline to 70% in Class I/II with no patients in NYHA Class IV (P < 0.0001). Mitral regurgitant volume was reduced from 27 mL (IQR 25-42 mL) to 8 mL (IQR 3-17 mL) (P = 0.018) and regurgitant fraction from 42% (IQR 34-54%) to 11% (IQR 8-24%) (P = 0.014). LV end-diastolic volume index [92 mL/m2 (IQR 74-107 mL/m2 ) vs. 67 mL/m2 (IQR 46-101 mL/m2 ), P = 0.065] and end-systolic volume index [50 mL/m2 (IQR 44-69 mL/m2 ) vs. 32 mL/m2 (IQR 20-53 mL/m2 ), P = 0.037] decreased. Total stroke volume remained unchanged [38 mL/m2 (IQR 33-43 mL/m2 ) vs. 33 mL/m2 (IQR 26-44 mL/m2 ), P = 0.695], while LV ejection fraction increased [43% (IQR 35-49%) vs. 54% (IQR 46-57%), P = 0.014]. Forward stroke volume, heart rate, and forward cardiac output were not significantly altered.

CONCLUSIONS

Among high-risk patients undergoing transcatheter mitral valve annuloplasty for symptomatic secondary MR, mortality was ~50% at 4 years. In the surviving patients, reduced MR severity was associated with reduced NYHA functional class, reverse LV remodelling, and improved LV function.

Managing the patient undergoing transcatheter aortic valve replacement with ongoing mitral regurgitation

INTRODUCTION

Significant mitral regurgitation (MR) frequently coexists in patients with severe symptomatic aortic stenosis undergoing transcatheter aortic valve replacement (TAVR). These patients have worse clinical outcomes than those with non-significant MR, especially if MR persists after treatment of the aortic stenosis. The optimal treatment approach for this challenging high-risk population is not well defined.

AREAS COVERED

This review aims to present the current literature on concomitant significant MR in the TAVR population, and to provide a comprehensive algorithmic approach for clinical decision-making in this challenging cohort of patients.

EXPERT OPINION

Concomitant mitral and aortic valve disease is a complex clinical entity. An exhaustive and comprehensive assessment of patient's clinical characteristics and mitral valve anatomy and function is required in order to assess the surgical risk, predict the MR response after AVR and evaluate the feasibility of percutaneous MV treatment if necessary. Further developments in transcatheter techniques will expand the indications for double valve treatment in operable and inoperable patients with concomitant significant MR and aortic stenosis.

Outcomes of transcatheter mitral valve repair for secondary mitral regurgitation by severity of left ventricular dysfunction

BACKGROUND

In the COAPT trial, transcatheter mitral valve repair with the MitraClip plus maximally tolerated guideline-directed medical therapy (GDMT) improved clinical outcomes compared with GDMT alone in symptomatic patients with heart failure (HF) and 3+ or 4+ secondary mitral regurgitation (SMR) due to left ventricular (LV) dysfunction.

AIMS

In this COAPT substudy, we sought to evaluate two-year outcomes in HF patients with reduced LV ejection fraction (HFrEF; LVEF ≤40%) versus preserved LVEF (HFpEF; LVEF >40%) and in those with severe (LVEF ≤30%) versus moderate (LVEF >30%) LV dysfunction.

METHODS

The principal effectiveness outcome was the two-year rate of death from any cause or HF hospitalisations (HFH). Subgroup analysis with interaction testing was performed according to baseline LVEF; 472 patients (82.1%) had HFrEF (mean LVEF 28.0%±6.2%; range 12% to 40%) and 103 (17.9%) had HFpEF (mean LVEF 46.6%±4.9%; range 41% to 65%), while 292 (50.7%) had severely depressed LVEF (LVEF ≤30%; mean LVEF 23.9%±3.8%) and 283 (49.3%) had moderately depressed LVEF (LVEF >30%; mean LVEF 39.0%±6.8%).

RESULTS

The two-year rate of death or HFH was 56.7% in patients with HFrEF and 53.4% with HFpEF (HR 1.16, 95% CI: 0.86-1.57, p=0.32). MitraClip reduced the two-year rate of death or HFH in patients with HFrEF (HR 0.50, 95% CI: 0.39-0.65) and HFpEF (HR 0.60, 95% CI: 0.35-1.05), pint=0.55. MitraClip was consistently effective in reducing the individual endpoints of mortality and HFH, improving MR severity, quality of life, and six-minute walk distance in patients with HFrEF, HFpEF, LVEF ≤30%, and LVEF >30%.

CONCLUSIONS

In the COAPT trial, among patients with HF and 3+ or 4+ SMR who remained symptomatic despite maximally tolerated GDMT, the MitraClip was consistently effective in improving survival and health status in patients with severe and moderate LV dysfunction and those with preserved LVEF.

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.

Clinical and Echocardiographic Predictors of Reduced Survival in Patient with Functional Mitral Regurgitation

Functional mitral regurgitation (FMR) is associated with a poor outcome in patients with reduced left ventricular ejection fraction (LVEF). Two recent studies of percutaneous mitral valvular repair therapy reported disparate results, likely due in part to variable risk among FMR patients. The aim of this study is to define echocardiographic factors of prognostic significance in FMR patients, and particularly to compare ischemic and nonischemic FMR. We followed three hundred sixteen consecutive patients (age 60 ± 14 years, men 70%) with FMR and LVEF ≤ 35% between January 2010 and December 2015 (mean follow-up 3.7 years). Patients were categorized into ischemic (39.6%) and nonischemic (60.4%). MR was graded according to the American Society of Echocardiography guidelines. Although echo findings were similar between ischemic and nonischemic patient, the incidence of death, heart transplantation (HT), or LVAD implantation was higher in ischemic than in nonischemic patients (Log rank p = 0.001). In age and gender adjusted multivariate (11 variables) Cox regression analysis, left atrium volume index (LAVI) was associated with death, HT, or LVAD with hazard ratio of 2.1 for patients with FMR (p = 0.003). LAVI greater than 48.7 mL/m² predicts adverse outcome in both nonischemic and ischemic FMR (AUC 0.62, p < 0.001). Combined ischemic FMR with LAVI ≥ 48.7 mL/m² had the highest incident rate of all groups. In conclusion, despite similar LV function and MR severity, ischemic FMR patients had higher mortality than nonischemic patients. Of all echocardiographic parameters, an LAVI ≥ 48.7 mL/m² predicted adverse clinical outcome.

Impact of mitral regurgitation in patients with worsening heart failure: insights from BIOSTAT-CHF

AIMS

Few data regarding the prevalence and prognostic impact of mitral regurgitation (MR) in patients with worsening chronic or new-onset acute heart failure (HF) are available. We investigated the role of MR in the BIOlogy Study to TAilored Treatment in Chronic Heart Failure (BIOSTAT-CHF).

METHODS AND RESULTS

We performed a retrospective post-hoc analysis including patients from both the index and validation BIOSTAT-CHF cohorts with data regarding MR status. The primary endpoint was a composite of all-cause death or HF hospitalization. Among 4023 patients included, 1653 patients (41.1%) had moderate-severe MR. Compared to others, patients with moderate-severe MR were more likely to have atrial fibrillation and chronic kidney disease and had larger left ventricular (LV) dimensions, lower LV ejection fraction (LVEF), worse quality of life, and higher plasma concentrations of N-terminal pro-B-type natriuretic peptide (NT-proBNP). A primary outcome event occurred in 697 patients with, compared to 836 patients without, moderate-severe MR [Kaplan-Meier 2-year estimate: 42.2% vs. 35.3%; hazard ratio (HR) 1.28; 95% confidence interval (CI) 1.16-1.41; log-rank P < 0.0001]. The association between MR and the primary endpoint remained significant after adjusting for baseline variables and the previously validated BIOSTAT-CHF risk score (adjusted HR 1.11; 95% CI 1.00-1.23; P = 0.041). Subgroup analyses showed a numerically larger impact of MR on the primary endpoint in patients with lower LVEF, larger LV end-diastolic diameter, and higher plasma NT-proBNP.

CONCLUSIONS

Moderate-severe MR is common in patients with worsening chronic or new-onset acute HF and is strongly associated with outcome, independently of other features related to HF severity.

Devices for transcatheter mitral valve repair: current technology and a glimpse into the future

Introduction: Due to a large unmet need for the treatment of mitral regurgitation, transcatheter mitral valve repair devices have emerged in the last decade as an alternative therapeutic option. Given the complexity of this disease, several device systems for transcatheter mitral valve repair have been developed and are categorized according to its mechanism of action; each device has advantages and disadvantages for certain clinical and pathophysiologic characteristics, and in order to improve outcomes, proper patient selection among other key points are fundamental.Areas covered: The purpose of this article is to review the current state-of-the-art technologies available for transcatheter mitral valve repair, patient suitability, outcomes, and future perspectives.Expert opinion: Transcatheter therapy for mitral regurgitation improves outcomes and pushes the boundaries of biomedical technology while maintaining scientific rigor for device development. Surgical and percutaneous procedures should be viewed as complements to treat a wider spectrum of patients affected by this entity. Future directions from multidisciplinary innovation and cooperation will consolidate this therapeutic option.

How does severe functional mitral regurgitation redefined by European guidelines affect pulmonary vascular resistance and hemodynamics in heart transplant candidates?

OBJECTIVE

Increased pulmonary artery pressure (PAP) and pulmonary vascular resistance (PVR) are important prognostic factors in patients with heart transplantation (HT). It is well known that severe mitral regurgitation increases pulmonary pressures. However, the European Society of Cardiology and the 6th World Symposium of pulmonary hypertension (PH) task force redefined severe functional mitral regurgitation (FMR) and PH, respectively. We aimed to investigate the effect of severe FMR on PAP and PVR based on these major redefinitions in patients with HT.

METHODS

A total of 212 patients with HT were divided into 2 groups: those with severe FMR (n=70) and without severe FMR (n=142). Severe FMR was defined as effective orifice regurgitation area ≥20 mm2 and regurgitation volume ≥30 mL where the mitral valve was morphologically normal. A mean PAP of >20 mm Hg was accepted as PH. Patients with left ventricular ejection fraction ≤25% were included in the study.

RESULTS

The systolic PAP, mean PAP, and PVR were higher in patients with severe FMR than in those without severe FMR [58.5 (48.0-70.2) versus 45.0 (36.0-64.0), p<0.001; 38.0 (30.2-46.6) versus 31.0 (23.0-39.5), p=0.004; 4.0 (2.3-6.8) versus 2.6 (1.2-4.3), p=0.001, respectively]. Univariate analysis revealed that the severe FMR is a risk factor for PVR ≥3 and 5 WU [odds ratio (OR): 2.0, 95% confidence interval (CI): 1.1-3.6, p=0.009; and OR: 3.2, 95% CI: 1.5-6.7, p=0.002]. The multivariate regression analysis results revealed that presence of severe FMR is an independent risk factor for PVR ≥3 WU and presence of combined pre-post-capillary PH (OR: 2.23, 95% CI: 1.30-3.82, p=0.003 and OR: 2.30, 95% CI: 1.25-4.26, p=0.008).

CONCLUSION

Even in the updated definition of FMR with a lower threshold, severe FMR is associated with higher PVR, systolic PAP, and mean PAP and appears to have an unfavorable effect on pulmonary hemodynamics in patients with HT.

Guide to functional mitral regurgitation: a contemporary review

Functional mitral regurgitation (FMR) occurs in the absence of organic mitral valve (MV) disease and is a result of LV dysfunction due to ischemic vs. non ischemic etiologies. The prevalence of FMR is increasing, as 2.0-2.5 million people in the USA were diagnosed with FMR in 2000-and this number is expected to double to 4 million by 2030. FMR tends to develop in a significant number of patients after myocardial infarction (MI) and many develop heart failure (HF) subsequently with mortality rates ranging from 15-40% at 1 year. Therefore, there has been much interest and effort to develop optimized methods for quantifying and classifying the severity of FMR, as well as developing effective therapeutic interventions to improve outcomes in patients with significant FMR. Echocardiogram is typically the primary diagnostic method of assessment, however, there have been various technological advances including cardiac CT and cardiac MRI that can better guide quantification and management of this disease. Management of this disease is mostly aimed at optimizing left ventricular (LV) remodeling with surgical and transcatheter management gaining more popularity with recent times. The purpose of this paper is to provide a comprehensive review of the current evaluation methods and interventional strategies for FMR.

10-Year Results of Mitral Repair and Coronary Bypass for Ischemic Regurgitation: A Randomized Trial

BACKGROUND

The decision to treat moderate ischemic mitral regurgitation (IMR) at the time of coronary artery bypass surgery (CABG) remains controversial. We previously conducted a prospective randomized trial that showed a benefit of adding restricted annuloplasty to bypass surgery (CABG-Ring group) in terms of IMR grade, New York Heart Association classification, and left ventricle reverse remodeling. Here, we present the long-term (>10 years) follow-up data from this randomized trial.

METHODS

The original trial arms accounted for 54 patients in the CABG-alone and 48 in the CABG-Ring group; patients were re-contacted for follow-up to obtain relevant clinical and echocardiographic information.

RESULTS

The mean follow-up was 160.4 ± 45.5 months. Survival probabilities in the CABG-alone and CABG-Ring groups were 96% vs 93% at 3 years, 85% vs 89% at 6 years, 79% vs 85% at 9 years, 77% vs 83% at 12 years, and 72% vs 80% at 15 years, respectively (P = .18) Freedom from at least moderate IMR or reintervention at last follow-up was also higher in the CABG-Ring group (P < .001). Compared with the CABG-alone group, the CABG-Ring group had a higher degree of left ventricular reverse remodeling (54.7 ± 6.9 mm vs 51.6 ± 6 mm, respectively; P = .03), lower New York Heart Association class (P < .001), and a lower rate of rehospitalization (P = .002).

CONCLUSIONS

Long-term follow-up data from our randomized trial further support the utility of performing restricted annuloplasty at the time of CABG to prevent further progression of IMR, mitral reintervention, and left ventricle remodeling. Untreated IMR was associated with significantly higher New York Heart Association class and rehospitalization.

Safety and Feasibility of MitraClip Implantation in Patients with Acute Mitral Regurgitation after Recent Myocardial Infarction and Severe Left Ventricle Dysfunction

Patients with severe mitral regurgitation (MR) after myocardial infarction (MI) have an increased risk of mortality. Transcatheter mitral valve repair may therefore be a suitable therapy. However, data on clinical outcomes of patients in an acute setting are scarce, especially those with reduced left ventricle (LV) dysfunction. We conducted a multinational, collaborative data analysis from 21 centers for patients who were, within 90 days of acute MI, treated with MitraClip due to severe MR. The cohort was divided according to median left ventricle ejection fraction (LVEF)-35%. Included in the study were 105 patients. The mean age was 71 ± 10 years. Patients in the LVEF < 35% group were younger but with comparable Euroscore II, multivessel coronary artery disease, prior MI and coronary artery bypass graft surgery. Procedure time was comparable and acute success rate was high in both groups (94% vs. 90%, p = 0.728). MR grade was significantly reduced in both groups along with an immediate reduction in left atrial V-wave, pulmonary artery pressure and improvement in New York Heart Association (NYHA) class. In-hospital and 1-year mortality rates were not significantly different between the two groups (11% vs. 7%, p = 0.51 and 19% vs. 12%, p = 0.49) and neither was the 3-month re-hospitalization rate. In conclusion, MitraClip intervention in patients with acute severe functional mitral regurgitation (FMR) due to a recent MI in an acute setting is safe and feasible. Even patients with severe LV dysfunction may benefit from transcatheter mitral valve intervention and should not be excluded.

Physiological and prognostic differences between types of exercise stress echocardiography for functional mitral regurgitation

Objective

Secondary mitral regurgitation (MR) demonstrates dynamic change during exercise. This prospective observational study aimed to compare exercise stress echocardiography (ESE) where handgrip exercise (handgrip-ESE) or semisupine ergometer exercise was performed (ergometer-ESE) for patients with secondary MR.

Methods

Handgrip-ESE and symptom-limited ergometer-ESE were performed for 53 patients (median age (IQR): 68 (58–78) years; 70% male) on the same day. Baseline global longitudinal strain (GLS) was 9.2% (6.0%–14.0%) and MR volume was 20 (14–26) mL. All-cause death and cardiac hospitalisation were tracked for median 439 (101–507) days.

Results

Handgrip-ESE induced slightly but significantly greater degrees of MR increase (median one grade increase; p<0.001) than ergometer-ESE, although the changes in other parameters, including GLS (+1.1% vs −0.6%, p<0.001), were significantly smaller. Correlations between the two examinations with respect to the changes in the echocardiographic parameters were weak. Kaplan-Meier analyses revealed poor improvement in GLS during ergometer-ESE, but not the change in MR, was associated with adverse events (p=0.0065). No echocardiographic change observed during handgrip-ESE was prognostic. After adjusting for a clinical risk score, GLS changes during ergometer-ESE remained significant in predicting the adverse events (HR 0.39, p=0.03) A subgroup analysis in patients with moderate or greater MR at baseline (n=27) showed the same results as in the entire cohort.

Conclusions

The physiological and prognostic implications of handgrip-ESE and ergometer-ESE findings significantly differ in patients with left ventricular dysfunction and secondary MR. The type of exercise to be performed in ESE should be carefully selected.

Ischemic Mitral Regurgitation: A Multifaceted Syndrome with Evolving Therapies

Dysfunction of the left ventricle (LV) with impaired contractility following chronic ischemia or acute myocardial infarction (AMI) is the main cause of ischemic mitral regurgitation (IMR), leading to moderate and moderate-to-severe mitral regurgitation (MR). The site of AMI exerts a specific influence determining different patterns of adverse LV remodeling. In general, inferior-posterior AMI is more frequently associated with regional structural changes than the anterolateral one, which is associated with global adverse LV remodeling, ultimately leading to different phenotypes of IMR. In this narrative review, starting from the aforementioned categorization, we proceed to describe current knowledge regarding surgical approaches in the management of IMR.

Percutaneous mitral valve repair with MitraClip device in hemodynamically unstable patients: A systematic review

BACKGROUND

Very few data exist on percutaneous mitral valve repair (PMVr) in unstable patients with concomitant moderate-severe mitral regurgitation (MR). The purpose of this systematic review was to evaluate baseline characteristics, management and clinical outcomes of critically ill patients undergoing PMVr with MitraClip.

METHODS

We conducted a systematic review of the published data on MitraClip from its first use in 2003 to December 2020. Studies referring to critically ill patients in cardiogenic shock or acute refractory pulmonary edema were included. A total of 40 publications including 254 patients with significant MR (Grade 4 in 91%) were included.

RESULTS

Mean age was 70 ± 12 years with mean Euroscore II and STS of 21 ± 13 and 20.5 ± 16, respectively. Clinical presentation was with cardiogenic shock and acute myocardial infarction in 72.8 and 60.0% of patients, respectively. Device success was achieved in 238 (93.7%) patients with a significant reduction in MR (Grade ≤ 2 in 91.8%, p < .001). The median weaning time from the procedure, to discontinuation of mechanical circulatory or respiratory support, was 2 days (IQR 1-4), with an in-hospital mortality and non-fatal complication rate of 12.6 and 9.1%, respectively. Kaplan-Meier curves estimated an overall mortality rate of 39.1% at 12-month follow-up, with persistent reduction in MR severity for survivors (Grade ≤ 2 in 81.3%) and one case of mitral valve reintervention.

CONCLUSIONS

Percutaneous mitral valve repair with MitraClip device is a technically feasible and potentially viable management option in high-risk patients with cardiogenic shock or refractory pulmonary edema and concomitant moderate-severe MR. Prospective trials are required to confirm these findings, and definitively determine the value of MitraClip in hemodynamically unstable patients.

Quantitating Mitral Regurgitation in Clinical Trials: The Need for a Uniform Approach

BACKGROUND

There is an established relationship between the degree of mitral regurgitation (MR) and prognosis. Quantitation of MR severity guides therapeutic approaches. Inconsistent definitions and categorization of MR severity in clinical studies limit meaningful comparisons between trials and compromise development of an effective evidence base. The purpose of this study was to quantify heterogeneity in grading systems for MR severity in the contemporary literature.

METHODS

We performed a systematic review of randomized (RCT) and propensity score (PS) adjusted clinical studies of MV interventions (surgical or percutaneous). A total of 35 articles from 2015-2020 were included (15 RCT, 20 PS).

RESULTS

There were 22 studies that reported MR severity in numerical categories, either values from the historical "plus" system or numerical MR grades, while 9 studies reported MR severity using text-only descriptive categories. Among the studies that used numerical categories, 2+ MR was defined as moderate in 64% of studies, mild in 27%, and mild-moderate in 9% and 3+ MR was defined as moderate in 14%, moderate-severe in 52%, and severe in 14%.

CONCLUSIONS

There was substantial variability in MR severity definition and reporting in contemporary clinical studies of MV interventions. We recommend the historical "plus" numerical grading system be abandoned and that inclusion and outcome criteria in MR clinical trials be based on American and European guideline-recommended categories as none/trace, mild, moderate, and severe. Adoption of these simple recommendations will improve the consistency and quality of MR clinical trial design and reporting.

Ischemia-Mediated Dysfunction in Subpapillary Myocardium as a Marker of Functional Mitral Regurgitation

OBJECTIVES

The goal of this study was to test whether ischemia-mediated contractile dysfunction underlying the mitral valve affects functional mitral regurgitation (FMR) and the prognostic impact of FMR.

BACKGROUND

FMR results from left ventricular (LV) remodeling, which can stem from myocardial tissue alterations. Stress cardiac magnetic resonance can assess ischemia and infarction in the left ventricle and papillary muscles; relative impact on FMR is uncertain.

METHODS

Vasodilator stress cardiac magnetic resonance was performed in patients with known or suspected coronary artery disease at 7 sites. Images were centrally analyzed for MR etiology/severity, mitral apparatus remodeling, and papillary ischemia.

RESULTS

A total of 8,631 patients (mean age 60.0 ± 14.1 years; 55% male) were studied. FMR was present in 27%, among whom 16% (n = 372) had advanced (moderate or severe) FMR. Patients with ischemia localized to subpapillary regions were more likely to have advanced FMR (p = 0.003); those with ischemia localized to other areas were not (p = 0.17). Ischemic/dysfunctional subpapillary myocardium (odds ratio: 1.24/10% subpapillary myocardium; confidence interval: 1.17 to 1.31; p < 0.001) was associated with advanced FMR controlling for infarction. Among a subgroup with (n = 372) and without (n = 744) advanced FMR matched (1:2) on infarct size/distribution, patients with advanced FMR had increased adverse mitral apparatus remodeling, paralleled by greater ischemic/dysfunctional subpapillary myocardium (p < 0.001). Although posteromedial papillary ischemia was more common with advanced FMR (p = 0.006), subpapillary ischemia with dysfunction remained associated (p < 0.001), adjusting for posteromedial papillary ischemia (p = 0.074). During follow-up (median 5.1 years), 1,473 deaths occurred in the overall cohort; advanced FMR conferred increased mortality risk (hazard ratio: 1.52; 95% confidence interval: 1.25 to 1.86; p < 0.001) controlling for left ventricular ejection fraction, infarction, and ischemia.

CONCLUSIONS

Ischemic and dysfunctional subpapillary myocardium provides a substrate for FMR, which predicts mortality independent of key mechanistic substrates.

Looking into the Mechanistic Link Between Mitral Regurgitation and Atrial Fibrillation

Atrial functional mitral regurgitation (AFMR) can occur in patients with atrial fibrillation despite a preserved left ventricular systolic function. AFMR has received attention as a cause of heart failure; it is a therapeutic target in patients with heart failure with atrial fibrillation. Mitral annular dilatation from atrial fibrillation-induced left atrial dilatation is necessary for the generation of AFMR. Posterior mitral leaflet hamstringing also relates to the generation of AFMR. Further mitral annular dilatation owing to progressive left atrial and left ventricular dilatations, with mitral regurgitation-induced volume overload, worsens AFMR.

The management of secondary mitral regurgitation in patients with heart failure: a joint position statement from the Heart Failure Association (HFA), European Association of Cardiovascular Imaging (EACVI), European Heart Rhythm Association (EHRA), and European Association of Percutaneous Cardiovascular Interventions (EAPCI) of the ESC

Secondary (or functional) mitral regurgitation (SMR) occurs frequently in chronic heart failure (HF) with reduced left ventricular (LV) ejection fraction, resulting from LV remodelling that prevents coaptation of the valve leaflets. Secondary mitral regurgitation contributes to progression of the symptoms and signs of HF and confers worse prognosis. The management of HF patients with SMR is complex and requires timely referral to a multidisciplinary Heart Team. Optimization of pharmacological and device therapy according to guideline recommendations is crucial. Further management requires careful clinical and imaging assessment, addressing the anatomical and functional features of the mitral valve and left ventricle, overall HF status, and relevant comorbidities. Evidence concerning surgical correction of SMR is sparse and it is doubtful whether this approach improves prognosis. Transcatheter repair has emerged as a promising alternative, but the conflicting results of current randomized trials require careful interpretation. This collaborative position statement, developed by four key associations of the European Society of Cardiology-the Heart Failure Association (HFA), European Association of Percutaneous Cardiovascular Interventions (EAPCI), European Association of Cardiovascular Imaging (EACVI), and European Heart Rhythm Association (EHRA)-presents an updated practical approach to the evaluation and management of patients with HF and SMR based upon a Heart Team approach.

Assessing proportionate and disproportionate functional mitral regurgitation with individualized thresholds

AIMS

The concept of proportionate/disproportionate functional mitral regurgitation (FMR) has been limited by the lack of a simple way to assess it and by the paucity of data showing its prognostic superiority. The aim of this study was to evaluate the prognostic value of an individualized method of assessing FMR proportionality.

METHODS AND RESULTS

We retrospectively identified 572 patients with at least mild FMR and reduced left ventricular ejection fraction (<50%) under medical therapy. To determine FMR proportionality status, we used an approach where a simple equation determined the individualized theoretical regurgitant volume (or effective regurgitant orifice area) threshold associated with haemodynamically significant FMR. Then, we compared the measured with the theoretical value to categorize the population into non-severe, proportionate, and disproportionate FMR. The primary endpoint was all-cause mortality. During a median follow-up of 3.8 years (interquartile range: 1.8-6.2), 254 patients died. The unadjusted mortality incidence per 100 persons-year rose as the degree of FMR disproportionality worsened. On multivariable analysis, disproportionate FMR remained independently associated with all-cause mortality [adjusted hazard ratio: 1.785; 95% confidence interval (CI): 1.249-2.550; P = 0.001]. The FMR proportionality concept showed greater discriminative power (C-statistic 0.639; 95% CI: 0.597-0.680) than the American (C-statistic 0.583; 95% CI: 0.546-0.621; P for comparison <0.001) and European guidelines (C-statistic 0.584; 95% CI: 0.547-0.620; P for comparison <0.001). When added to any of the before-mentioned guidelines, FMR proportionality also improved risk stratification by reclassifying patients into lower and higher risk subsets.

CONCLUSION

Disproportionate FMR is independently associated with all-cause mortality and improves the risk stratification of current guidelines.

Functional outcomes with Carillon device over 1 year in patients with functional mitral regurgitation of Grades 2+ to 4+: results from the REDUCE-FMR trial

AIMS

The objective of this study was to compare functional outcomes through 1 year in patients with core-lab verified moderate to severe (Grades 2+ to 4+) functional mitral regurgitation (FMR) treated with the Carillon device or control in the blinded sham-controlled REDUCE-FMR (Carillon Mitral Contour System for Reducing Functional Mitral Regurgitation) study.

METHODS AND RESULTS

The main outcomes of this analysis were the change in 6 min walk test (6MWT) distance, incidence of heart failure hospitalization or death, change in New York Heart Association (NYHA) class, and change in Kansas City Cardiomyopathy Questionnaire (KCCQ) score through 1 year of follow-up. The minimum clinically important difference (MCID) was defined as a ≥30 m increase in 6MWT distance, an NYHA decrease in ≥1 class, and a ≥3 point increase in KCCQ score. The proportion of patients achieving the MCID in each treatment group was compared using Fisher's exact test, and the number needed to treat (NNT) with the Carillon device was calculated. Among 83 patients (62 Carillon and 21 sham), no statistically significant group differences were observed in the baseline characteristics. All outcomes at 1 year numerically favoured the Carillon group, including MCID for the 6MWT distance (59% vs. 23%, P = 0.029; NNT = 2.8), NYHA class (48% vs. 33%, P = 0.38; NNT = 6.9), KCCQ score (69% vs. 47%, P = 0.14; NNT = 4.5), and freedom from heart failure hospitalization or death (60% vs. 48%, P = 0.45; NNT = 8.3).

CONCLUSIONS

REDUCE-FMR was the first blinded sham-controlled trial to report outcomes with percutaneous therapy for the treatment of FMR. Trends towards improvement in mean 6MWT distance, KCCQ score, and NYHA class were observed with the Carillon device. A substantially higher number of patients achieved MCID for all patient-centred outcomes with the Carillon device compared with the sham procedure.

Exercise Right Heart Catheterisation in Cardiovascular Diseases: A Guide to Interpretation and Considerations in the Management of Valvular Heart Disease

The use of exercise right heart catheterisation for the assessment of cardiovascular diseases has regained attention recently. Understanding physiologic haemodynamic exercise responses is key for the identification of abnormal haemodynamic patterns. Exercise total pulmonary resistance >3 Wood units identifies a deranged haemodynamic response and when total pulmonary resistance exceeds 3 Wood units, an exercise pulmonary artery wedge pressures/cardiac output slope >2 mmHg/l/min indicates the presence of underlying exercise-induced pulmonary hypertension related to left heart disease. In the evolving field of transcatheter interventions for valvular heart disease, exercise right heart catheterisation may objectively unmask symptoms and underlying haemodynamic abnormalities. Further studies are needed on the use of the procedure to inform the selection of patients who might receive the most benefit from transcatheter interventions for valvular heart diseases.

Importance of Myocardial Fibrosis in Functional Mitral Regurgitation: From Outcomes to Decision-Making

Functional mitral regurgitation (FMR) is a common and complex valve disease, in which severity and risk stratification is still a conundrum. Although risk increases with FMR severity, it is modulated by subjacent left ventricular (LV) disease. The extent of LV remodeling and dysfunction is traditionally evaluated by echocardiography, but a growing body of evidence shows that myocardial fibrosis (MF) assessment by cardiac magnetic resonance (CMR) may complement risk stratification and inform treatment decisions. This review summarizes the current knowledge on the comprehensive evaluation that CMR can provide for patients with FMR, in particular for the assessment of MF and its potential impact in clinical decision-making.