MitraClip and left ventricular reverse remodelling: a strain imaging study

Mitral Transcatheter Edge-to-Edge Repair and Clinical Value of Novel Echocardiographic Biomarkers: A Hypothesis-Generating Study

BACKGROUND

Longitudinal data on reverse cardiac remodeling and outcomes after transcatheter edge-to-edge repair (TEER) are limited.

METHODS

A total of 78 patients with severe mitral regurgitation (MR) were included retrospectively. All patients had echocardiography at baseline and again six months after TEER. They were monitored for a primary composite endpoint, consisting of heart failure hospitalization and cardiovascular death, over 13 months.

RESULTS

Significant decreases in the left ventricular ejection fraction (LVEF), all myocardial work indices (except global wasted work), and the left atrial reservoir were observed after TEER. Additionally, there was a decrease in the pulmonary artery systolic pressure and an increase in the tricuspid annular plane systolic excursion/pulmonary artery systolic pressure (TAPSE/PASP) ratio. A post-TEER TAPSE/PASP ratio of <0.47 (HR: 4.76, p-value = 0.039), and a post-TEER left atrial reservoir of <9.0% (HR: 2.77, p-value = 0.047) were associated with the primary endpoint.

CONCLUSIONS

Echocardiography post-TEER reflects impairment in ventricular performance due to preload reduction and right ventricle and pulmonary artery coupling improvement. Short-term echocardiography after TEER identifies high-risk patients who could benefit from a close clinical follow-up. The prognostic significance of LA strain and the TAPSE/PASP ratio should be validated in subsequent large-scale prospective studies.

Intraoperative Assessment of Noninvasive Left Ventricular Myocardial Work Indices in Patients Undergoing Aortic Valve Replacement

OBJECTIVE

Evaluation of noninvasive left ventricular (LV) myocardial work (MW) enables insights into cardiac contractility and efficacy beyond conventional echocardiography. However, there is limited intraoperative data on patients undergoing surgical aortic valve replacement (AVR). The aim of this study was to describe the feasibility and the intraoperative course of this technique of ventricular function assessment in these patients and compare it to conventional two (2D)- and three-dimensional (3D) echocardiographic measurements and strain analysis.

DESIGN

Prospective observational study.

SETTING

Single university hospital.

PARTICIPANTS

Twenty-five patients scheduled for isolated AVR with preoperative preserved left and right ventricular function, sinus rhythm, without significant other heart valve disease or pulmonary hypertension, and an uneventful intraoperative course.

INTERVENTIONS

Transesophageal echocardiography was performed after induction of anesthesia (T1), after termination of cardiopulmonary bypass (T2), and after sternal closure (T3). Evaluation was performed in stable hemodynamics, in sinus rhythm or atrial pacing and vasopressor support with norepinephrine ≤ 0.1 µg/kg/min.

MEASUREMENTS AND MAIN RESULTS

EchoPAC v206 software (GE Vingmed Ultrasound AS, Norway) was used for analysis of 2D and 3D LV ejection fraction (EF), LV global longitudinal strain (GLS), LV global work index (GWI), LV global constructive work (GCW), LV global wasted work (GWW), and LV global work efficiency (GWE). Estimation of myocardial work was feasible in all patients. Although there was no significant difference in the values of 2D and 3D EF, GWI and GCW decreased significantly after AVR (T1 v T2, 1,647 ± 380 mmHg% v 1,021 ± 233 mmHg%, p < 0.001; T1 v T2, 2,095 ± 433 mmHg% v 1,402 ± 242 mmHg%, p < 0.001, respectively), while GWW remained unchanged (T1 v T2, 296 mmHg% [IQR 178-452) v 309 mmHg% [IQR 255-438), p = 0.97). This resulted in a decreased GWE directly after bypass (T1 v T2, 84% ± 6% v 78% ± 5%, p < 0.001), but GWE already improved at the end of surgery (T2 v T3, 78% ± 5% v 81% ± 5%, p = 0.003). There was no significant change in the values of GWI, GCW, or 2D and 3D LVEF before and after sternal closure (T2 v T3).

CONCLUSION

LV MW analysis showed a reduction of LV workload after bypass in our group of patients, which was not detected by conventional echocardiographic measures. This evolving technique provides deeper insights into cardiac energetics and efficiency in the perioperative course of aortic valve replacement surgery.

Moving from left ventricular ejection fraction to deformation imaging in mitral valve regurgitation

The increasing prevalence of valvular heart diseases, specifically mitral regurgitation (MR), underscores the need for a careful and timely approach to intervention. Severe MR, whether primary or secondary, when left untreated leads to adverse outcomes, emphasizing the critical role of a timely surgical or transcatheter intervention. While left ventricular ejection fraction (LVEF) remains the guideline-recommended measure for assessing left ventricle damage, emerging evidence raises concerns regarding its reliability in MR due to its volume-dependent nature. This review summarizes the existing literature on the role of LVEF and deformation imaging techniques, emphasizing the latter's potential in providing a more accurate evaluation of intrinsic myocardial function. Moreover, it advocates the need for an integrated approach that combines traditional with emerging measures, aiming to optimize the management of patients with MR. It attempts to highlight the need for future research to validate the clinical application of deformation imaging techniques through large-scale studies.

Myocardial work and left heart deformation parameters across primary mitral regurgitation severity

AIMS

Myocardial work (MW) estimation by pressure-strain loops using speckle tracking echocardiography (STE) has shown to evaluate left ventricular (LV) contraction overcoming the load-dependency limit of LV global longitudinal strain (GLS). This has proved useful in hemodynamic variation settings e.g. heart failure and valvular heart disease. However, the variation of MW and strain parameters across different stages of primary mitral regurgitation (MR) and its impact on symptoms, which was the aim of our study, has never been investigated.

METHODS AND RESULTS

Consecutive patients with mild, moderate and severe MR were prospectively enrolled. Exclusion criteria were: chronic atrial fibrillation, valvular heart prosthesis, previous cardiac surgery. Clinical evaluation, blood sample tests, ECG and echocardiography with STE and MW measurement were performed. Patients were then divided into groups according to MR severity. Differences among the groups and predictors of symptoms (as NYHA class≥2) were explored as study endpoints. Overall, 180 patients were enrolled (60 mild,60 moderate,60 severe MR). LV GLS and global peak atrial longitudinal strain (PALS) reduced according to MR severity. Global constructive work (GCW) and global wasted work (GWW) significantly improved, while global work efficiency (GWE) reduced, in patients with moderate and severe MR. Among echocardiographic parameters, global PALS emerged as the best predictor of NYHA class (p < 0.001;area under curve,AUC = 0.7).

CONCLUSIONS

MW parameters accurately describe the pathophysiology of MR, with initial attempt of LV increased contractility to compensate volume overload parallel to the disease progress, although with low efficacy, while global PALS is the most associated with the burden of MR symptoms.

An Updated Meta-Analysis of Treatment in Patients with Heart Failure Complicated Ventricular Functional Mitral Regurgitation

Background

Ventricular functional mitral regurgitation (FMR) is a common morbidity in patients with heart failure (HF). In addition to guideline-directed medical therapy, mitral valve (MV) repair or replacement has become an option for such patients. However, the impact of different treatments on cardiac remodeling, function, and clinical outcomes remains unclear.

Methods

We systematically searched PubMed, EMBASE, Medline, Clinical Trials.gov, and the Cochrane Central Register of Controlled Trials with search terms related to mitral regurgitation, mitral valve repair, surgical mitral valve replacement, mitral annuloplasty device, and MitraClip. The outcomes were left ventricular ejection fraction (LVEF), left ventricular (LV) remodeling, all-cause mortality, cardiovascular death, and HF hospitalization. Sensitivity analysis was performed by removing high-bias risk studies. The analysis was done by Review Manager 5.4 Analyzer and MedCalc Statistical Software version 19.2.6.

Results

This meta-analysis included 10 studies with a total of 2533 patients (567 with transcatheter MitraClip, 823 with surgical MV repair, 651 with surgical MV replacement, and 492 with medical therapy). Our meta-analysis revealed that surgical MV repair had significant improvement in LVEF compared to the surgical MV replacement (mean differences (MD) 2.32, [95% CI 0.39, 4.25]), while transcatheter MitraClip treatment was associated with LVEF reduction (MD -4.82, [95% CI -7.29, -2.34]). In terms of LV remodeling, transcatheter MitraClip treatment was associated with improvement in left ventricular end-diastolic volume (MD -10.36, [95% CI -18.74, -1.99]). Furthermore, compared to surgical MV replacement, surgical MV repair was not associated with a reduction of all-cause mortality (risk ratio (RR) 0.83, [95% CI 0.61, 1.13]) and cardiovascular death (RR 0.95, [95% CI 0.56, 1.62]), while transcatheter MitraClip was associated with reduced risk of all-cause mortality (RR 0.87, [95% CI 0.78, 0.98]).

Conclusions

Surgical MV repair was associated with significant improvement in LVEF but had no significant effect on all-cause mortality compared to surgical MV replacement. Transcatheter MitraClip was associated with better long-term survival than the non-MitraClip group, thus, transcatheter MitraClip could be considered an alternative treatment in patients with HF-complicated ventricular FMR.

Early improvement of global longitudinal strain after iron deficiency correction in heart failure with reduced ejection fraction

BACKGROUND

Iron deficiency correction with ferric carboxymaltose improves symptoms and reduces rehospitalization in patients with reduced left ventricular ejection fraction. The mechanisms underlying these improvements are poorly understood. This study aimed to determine changes in left ventricular contractility after iron treatment as reflected in global longitudinal strain.

METHODS

Prospective single-center study including 43 adults with reduced ejection fraction, non-anemic iron deficiency, and functional class II-III heart failure despite optimal medical treatment. Global longitudinal strain through speckle-tracking echocardiography was measured at baseline and 4 weeks after ferric carboxymaltose.

RESULTS

A significant improvement in global longitudinal strain was detected (from -12.3% ± 4.0% at baseline to -15.6% ± 4.1%, p < .001); ferritin and transferrin saturation index had increased, but ejection fraction presented no significant changes (baseline 35.7% ± 4.6%, follow-up 37.2% ± 6.6%, p = .073).

CONCLUSIONS

In patients with heart failure and reduced ejection fraction, the correction of iron deficiency with ferric carboxymaltose is associated with an early improvement in global longitudinal strain, possibly suggesting a direct effect of iron correction on myocardial contractility.

Percutaneous Mitral Valve Repair for Secondary Mitral Regurgitation: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis aimed to investigate whether percutaneous mitral valve repair (PMVr) using MitraClip was more effective than surgery or medical therapy for long-term morbidity and mortality. We searched MEDLINE, EMBASE, and CENTRAL (Cochrane Library) databases to identify relevant studies that recruited adult patients with functional or secondary mitral valve regurgitation who underwent PMVr with MitraClip implantation using appropriate search terms and Boolean operators. The odds ratios (ORs) were pooled using the random-effects model. A total of 14 studies recruiting 2,593 patients were included. Within 12 months of follow-up, patients who underwent PMVr did not maintain mitral valve regurgitation grade 2+ (OR 0.22, 95% confidence interval [CI] 0.12 to 0.41, p <0.0001, I2 = 0.0%, p = 0.52) or symptom-free heart failure (OR 0.47, 95% CI 0.29 to 0.77, p = 0.0028, I2 = 0.0%, p = 0.66) compared with their surgical counterparts. Patients were more likely to be rehospitalized for heart failure (OR 2.79, 95% CI 1.54 to 5.05, p = 0.0007, I2 = 0.0%, p = 0.51). However, there was no difference between the groups in terms of all-cause or cardiovascular mortality. Whereas, in comparison with medical therapy, PMVr significantly reduced all-cause mortality at 12 and ≥24 months of follow-up (OR 0.41, 95% CI 0.24, 0.69, p = 0.0009, I2 = 32%, p = 0.23 and OR 0.55, 95% CI 0.40, 0.75, p = 0.0002, I2 = 0.0%, p = 0.45, respectively). In conclusion, there was no difference in all-cause death at 12 or 24 months of follow-up between PMVr and the surgical approach, but the durability of valvular repair was inferior with PMVr. In comparison with medical therapy, there was a significant reduction in mortality with PMVr.

The application of radiology for dilated cardiomyopathy diagnosis, treatment, and prognosis prediction: a bibliometric analysis

Background

Radiology plays a highly crucial role in the diagnosis, treatment, and prognosis prediction of dilated cardiomyopathy (DCM). Related research has increased rapidly over the past few years, but systematic analyses are lacking. This study thus aimed to provide a reference for further research by analyzing the knowledge field, development trends, and research hotspots of radiology in DCM using bibliometric methods.

Methods

Articles on the radiology of DCM published between 2002 and 2021 in the Web of Science Core Collection database (WoSCCd) were searched and analyzed. Data were retrieved and analyzed using CiteSpace V, VOSviewer, and Scimago Graphic software, and included the name, research institution, and nationality of authors; journals of publication; and the number of citations.

Results

A total of 4,257 articles were identified on radiology of DCM from WoSCCd. The number of articles published in this field has grown steadily from 2002 to 2021 and is expected to reach 392 annually by 2024. According to subfields, the number of papers published in cardiac magnetic resonance field increased steadily. The authors from the United States published the most (1,364 articles, 32.04%) articles. The author with the most articles published was Bax JJ (54 articles, 1.27%) from Leiden University Medical Center. The most cited article was titled "2016 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure", with 138 citations. Citation-based clustering showed that arrhythmogenic cardiomyopathy, T1 mapping, and endomyocardial biopsy are the current hots pots for research in DCM radiology. The most frequently occurring keyword was "dilated cardiomyopathy". The keyword-based clusters mainly included "late gadolinium enhancement", "congestive heart failure", "cardiovascular magnetic resonance", "sudden cardiac death", "ventricular arrhythmia", and "cardiac resynchronization therapy".

Conclusions

The United States and Northern Europe are the most influential countries in research on DCM radiology, with many leading distinguished research institutions. The current research hots pots are myocardial fibrosis, risk stratification of ventricular arrhythmia, the prognosis of cardiac resynchronization therapy (CRT) treatment, and subtype classification of DCM.

Changes in Left Ventricular Global Longitudinal Strain in Patients With Heart Failure and Secondary Mitral Regurgitation: The COAPT Trial

Background Left ventricular (LV) global longitudinal strain (GLS) provides incremental prognostic information over LV ejection fraction in patients with heart failure (HF) and secondary mitral regurgitation. We examined the prognostic impact of LV GLS improvement in this population. Methods and Results The COAPT (Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients With Functional Mitral Regurgitation) trial randomized symptomatic patients with HF with severe (3+/4+) mitral regurgitation to transcatheter edge-to-edge repair with the MitraClip device plus maximally tolerated guideline-directed medical therapy (GDMT) versus GDMT alone. LV GLS was measured at baseline and 6-month follow-up. The relationship between the improvement in LV GLS from baseline to 6 months and the composite of all-cause death or HF hospitalization between 6- and 24-month follow-up were assessed. Among 383 patients, 174 (45.4%) had improved LV GLS at 6-month follow-up (83/195 [42.6%] with transcatheter edge-to-edge repair+GDMT and 91/188 [48.4%] with GDMT alone; P=0.25). Improvement in LV GLS was strongly associated with reduced death or HF hospitalization between 6 and 24 months (P<0.009), with similar risk reduction in both treatment arms (Pinteraction=0.40). By multivariable analysis, LV GLS improvement at 6 months was independently associated with a lower risk of death or HF hospitalization (hazard ratio [HR], 0.55 [95% CI, 0.36-0.83]; P=0.009), death (HR, 0.48 [95% CI, 0.29-0.81]; P=0.006), and HF hospitalization (HR, 0.50 [95% CI, 0.31-0.81]; P=0.005) between 6 and 24 months. Conclusions Among patients with HF and severe mitral regurgitation in the COAPT trial, improvement in LV GLS at 6-month follow-up was associated with improved outcomes after both transcatheter edge-to-edge repair and GDMT alone between 6 and 24 months. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT01626079.

Global Longitudinal Strain Predicts Outcomes in Patients with Reduced Left Ventricular Function Undergoing Transcatheter Edge-to-Edge Mitral Repair

BACKGROUND

The timing and selection of optimal candidates for mitral transcatheter edge-to-edge valve repair remains to be fully determined, especially in cases with severely depressed left ventricular ejection fraction (LVEF). The objective of this study is to evaluate the prognostic value of myocardial strain (LVGLS) in this setting.

METHODS

Retrospectively, 172 consecutive patients with LVEF ≤40% and severe MR treated with MitraClip were included. Four groups were generated according to the LVEF (<30% or ≥30%) and median LVGLS. The primary end-point was cardiovascular mortality.

RESULTS

Procedural success was high (96.5%) and complications were rare. At one-year follow-up, 82.5% of patients maintained MR grade ≤2, 79.2% were at a NYHA class ≤II and a reduction of 80% in heart failure admissions was observed in all groups. Interestingly, among patients with a more depressed LVEF, LVGLS was found to be an independent predictor for cardiovascular mortality (HR: 3.3; 95% CI: 1.1-10, p = 0.023).

CONCLUSIONS

Mitral valve repair with MitraClip is safe and it improves the mid-term functional class of patients regardless of LVEF. LVGLS can help in the selection of optimal candidates and timing for this procedure, as well as in the recognition of those patients with worse prognoses.

Prognostic value of left ventricular global longitudinal strain in mitral regurgitation: a systematic review

Conventional echocardiographic assessment may overestimate the left ventricular (LV) function in mitral regurgitation (MR). LV global longitudinal strain (GLS) is more sensitive marker to detect subclinical LV dysfunction. Multiple studies have investigated the prognostic value of LV-GLS in MR to examine its potential to determine the timing and indication of intervention. This systematic review aimed to assess the prognostic value of LV-GLS in patients with mitral regurgitation (MR) to define its clinical applicability. PUBMED and EMBASE were queried through July 2021 to identify studies investigating the prognostic value of LV-GLS in MR. A total of 24 observational studies with 5267 patients were identified. Sixteen studies investigated for primary MR, 7 studies for secondary MR, and 1 study for both. Most studies included patients who underwent intervention. There was significant heterogeneity in patient population, intervention status, follow-up period, LV-GLS cutoff value, outcomes, and statistical methods among the studies. Meta-analysis was not performed considering the significant variability. With exception to 1 study, all studies demonstrated significant association between impaired LV-GLS and worse clinical and echocardiographic outcomes in primary MR. Prognostic value of LV-GLS in secondary MR was less certain due to inconsistent findings and limited reporting. LV-GLS is a promising parameter of prognostication in primary MR and can be considered as alternative to determine the timing of intervention. However, the optimal cutoff value remains unclear. The prognostic value of LV-GLS in secondary MR is less clear. Further large-scale prospective study is warranted before its routine clinical application.

Acute and Chronic Changes in Myocardial Work Parameters in Patients with Severe Primary Mitral Regurgitation Undergoing Transcatheter Edge-to-Edge Repair

BACKGROUND

The noninvasive assessment of myocardial work (MW) allows for the evaluation of left ventricular (LV) performance by considering the effect of LV afterload. This study aims to evaluate the acute and chronic impact of transcatheter edge-to-edge repair (TEER) on MW parameters and LV remodeling in patients with severe primary mitral regurgitation (PMR).

METHODS

A total of 71 patients (age: 77 ± 9 years, females: 44%) with moderate-to-severe or severe PMR (effective regurgitant orifice: 0.57 ± 0.31 cm2; regurgitant volume: 80 ± 34 mL; LV end-systolic diameter: 42 ± 12 mm) underwent TEER after a global assessment by the heart team. MW indices were evaluated before the procedure, at hospital discharge, and at 1-year follow-up. LV remodeling was described as the percentage variation in LVEDV between baseline and 1-year follow-up.

RESULTS

TEER caused an acute reduction in LVEF, global longitudinal strain (GLS), global MW index (GWI), work efficiency (GWE), and mechanical dispersion (MD) and a significant increase in wasted work (GWW). One year after the procedure, GLS, GWI, GWE, and MD recovered, whereas GWW remained significantly impaired. Baseline GWW (β = -0.29, p = 0.03) was an independent predictor of LV reverse remodeling at 1-year follow-up.

CONCLUSIONS

In patients with severe PMR undergoing TEER, the acute reduction in LV preload causes significant impairment to all the parameters of LV performance. Baseline GWW was the only independent predictor of LV reverse remodeling, suggesting that a lower myocardial energetic efficiency in the context of chronic preload increase might impact the left ventricular response to mitral regurgitation correction.

[Clinical and echocardiographic parameters associated with the alteration of global longitudinal strain in secondary mitral regurgitation]

INTRODUCTION

Left ventricular systolic function may be overestimated in patients with secondary mitral regurgitation when using left ventricle ejection fraction. The Global longitudinal strain is a measure less dependent on left ventricle load. However, the clinical and echocardiographic parameters associated with the alteration of Global longitudinal strain in secondary mitral regurgitation have not been evaluated.

MATERIAL AND METHODS

A total of 96 patients (mean age 62.3 ± 12.1 years, 59.3% male) with secondary mitral regurgitation and low left ventricle ejection fraction < 50% were included. The study population was subdivided according to the Global longitudinal strain value with which an increased risk of all-cause mortality was associated (Global longitudinal strain < 7.0%, left ventricle systolic function impaired compared to Global longitudinal strain ≥ 7.0%, in absolute value). The clinical and echocardiographic endpoints are analysed in both groups of patients.

RESULTS

The strong and clear correlation between Global longitudinal strain (mean ± standard deviation: 7,2 ± 2,7) and parameters of systolic function (left ventricle ejection fraction mean ± standard deviation: 32,4 ± 8,0%) and contractility (dp/dt mean ± standard deviation: 682,5 ± 204,7 mmHg/s). the mean of left ventricle ejection fraction = 26.4 ± 5.3% in the Global longitudinal strain < 7 group, and the bivariate study using the 30% threshold shows that the Global longitudinal strain < 7 group presents a more altered left ventricle ejection fraction with odds ratio = 12, 5 (CI: 4.7-33.0) p < 0.001. In multivariate analysis of ultrasound parameters and linear regression shows a significant correlation between Global longitudinal strain and left ventricle ejection fraction (p < 0.001). The dp/dt analysis found a mean of 509.3 ± 99.1 mmHg/s in the Global longitudinal strain < 7 group and of 822.9 ± 154.1 in the Global longitudinal strain ≥ 7 group with significant difference (p < 0.001). In bivariate and multivariate analysis, the alteration of Global longitudinal strain is associated with a significantly lower dp / dt p < 0.001.

CONCLUSION

A Global longitudinal strain < 7 (in absolute value) reflects a severe impairment of left ventricle function. In addition, several parameters were associated with this severe alteration of the Global longitudinal strain, namely a lower left ventricle ejection fraction, a lower dp/dt and more severe symptoms permitting to characterized this group of patients in addition to an integration in a multiparametric evaluation of the secondary mitral regurgitation.

Myocardial Work in Echocardiography

Myocardial work is an emerging tool in echocardiography that incorporates left ventricular afterload into global longitudinal strain analysis. Myocardial work correlates with myocardial oxygen consumption, and work efficiency can also be assessed. Myocardial work has been evaluated in a variety of clinical conditions to assess the added value of myocardial work compared to left ventricular ejection fraction and global longitudinal strain. This review showcases the current use of myocardial work in adult echocardiography and its possible role in cardiac pathologies.

Intraoperative Noninvasive Left Ventricular Myocardial Work Indices in Patients Undergoing On-Pump Coronary Artery Bypass Surgery

OBJECTIVES

Noninvasive echocardiographic analysis of left ventricular (LV) myocardial work (MW) enables insights into cardiac mechanics, contractility, and efficacy beyond ejection fraction (EF) and global longitudinal strain (GLS). However, there are limited perioperative data on patients undergoing coronary artery bypass graft (CABG) surgery. The authors aimed to describe the feasibility and the intraoperative course of this novel assessment tool of ventricular function in these patients, and compare it to conventional 2-dimensional (2D) and 3-dimensional (3D) echocardiographic parameters and strain analysis.

DESIGN

A prospective observational study.

SETTING

At a single university hospital.

PARTICIPANTS

Twenty-five patients with preoperative preserved LV and right ventricular function, sinus rhythm, without significant heart valve disease or pulmonary hypertension, and an uncomplicated intraoperative course scheduled for isolated on-pump CABG surgery.

INTERVENTIONS

Transesophageal echocardiography (TEE) was performed intraoperatively after the induction of anesthesia (T1), after termination of cardiopulmonary bypass (T2), and after sternal closure (T3). All measurements were performed under stable hemodynamic conditions, in sinus rhythm or atrial pacing, and vasopressor support with norepinephrine ≤ 0.1 µg/kg/min.

MEASUREMENTS AND MAIN RESULTS

The EchoPAC v204 software (GE Vingmed Ultrasound AS, Norway) was used for analysis of 2D and 3D LVEF, LV GLS, LV global work index (GWI), LV global constructive work (GCW), LV global wasted work (GWW), and LV global work efficiency (GWE). The MW analysis was feasible in all patients. Although there was no significant difference in the values of 2D and 3D EF during the intraoperative interval, GLS deteriorated significantly after CABG compared to assessment after induction of anesthesia (T1 v T2, -13.3 ± 3.0% v -11.6 ± 3.1%; p = 0.012). The GWI declined significantly after surgery (T1 v T2, 1,224 ± 312 mmHg% v 940 ± 267 mmHg%; p < 0.001), as well as GCW (T1 v T2, 1,460 ± 312 mmHg% v 1,244 ± 336 mmHg%; p = 0.005). The GWW increased after CABG (T1 v T2, 143 mmHg% (IQR 99-183) v 251 mmHg% (IQR 179-361); p < 0.001), and GWE decreased (T1 v T2, 89% (IQR 85-92) v 80% (IQR 75-87); p < 0.001). There were no significant changes in the values of 2D and 3D EF, GLS, GWI, GCW, GWW, and GWE before and after sternal closure (T2 v T3).

CONCLUSION

The intraoperative analysis of noninvasive echocardiographically-assessed LV MW indices is feasible. In the short-term period after uncomplicated on-pump CABG, GLS, as well as global and constructive MW, decreased, whereas wasted work increased, resulting in a less efficient left ventricle. None of these aspects was detected by conventional echocardiographic parameters. Therefore, strain and MW analysis might be more sensitive parameters in detecting myocardial dysfunction by TEE in the perioperative setting, adding information on perioperative cardiac energetics.

ECHOCARDIOGRAPHIC METHODS FOR ASSESSING LEFT VENTRICULAR SYSTOLIC FUNCTION

Transthoracic echocardiography (TTE) is the recommended primary method of assessing cardiac function. The measurement of LVEF determines the strategy for treatment of patients, as well as influences their prognosis. 3D echocardiography has higher accuracy and reproducibility than 2D echocardiography; hence it is currently recommended for volume and LVEF measurements. New echocardiographic techniques: global longitudinal strain measured by speckle tracking and myocardial work allow earlier detection of myocardial abnormalities. In addition, they have greater sensitivity in detecting ischemia, fibrosis and left ven¬tricular systolic dyssynchrony. In some myocardial pathologies, such as amyloidosis, hypertrophic cardiomyopathy or Chagas disease, we observe characteristic patterns of myocardial deformation (strain), which are their hallmarks. Myocardial work, on the other hand, allows assessment of contractility independent of the effect of afterload. The new echocardiographic techniques provide additional diagnostic tools for assessing left ventricular systolic function and informa¬tion on prognosis, and hence their use can be expected to become more widespread in daily clinical practice.

Heart failure: an update from the last years and a look at the near future

In the last years, major progress occurred in heart failure (HF) management. Quadruple therapy is now mandatory for all the patients with HF with reduced ejection fraction. Whilst verciguat is becoming available across several countries, omecamtiv mecarbil is waiting to be released for clinical use. Concurrent use of potassium-lowering agents may counteract hyperkalaemia and facilitate renin-angiotensin-aldosterone system inhibitor implementations. The results of the EMPagliflozin outcomE tRial in Patients With chrOnic heaRt Failure With Preserved Ejection Fraction (EMPEROR-Preserved) trial were confirmed by the Dapagliflozin in Heart Failure with Mildly Reduced or Preserved Ejection Fraction (DELIVER) trial, and we now have, for the first time, evidence for treatment of also patients with HF with preserved ejection fraction. In a pre-specified meta-analysis of major randomized controlled trials, sodium-glucose co-transporter-2 inhibitors reduced all-cause mortality, cardiovascular (CV) mortality, and HF hospitalization in the patients with HF regardless of left ventricular ejection fraction. Other steps forward have occurred in the treatment of decompensated HF. Acetazolamide in Acute Decompensated Heart Failure with Volume Overload (ADVOR) trial showed that the addition of intravenous acetazolamide to loop diuretics leads to greater decongestion vs. placebo. The addition of hydrochlorothiazide to loop diuretics was evaluated in the CLOROTIC trial. Torasemide did not change outcomes, compared with furosemide, in TRANSFORM-HF. Ferric derisomaltose had an effect on the primary outcome of CV mortality or HF rehospitalizations in IRONMAN (rate ratio 0.82; 95% confidence interval 0.66-1.02; P = 0.070). Further options for the treatment of HF, including device therapies, cardiac contractility modulation, and percutaneous treatment of valvulopathies, are summarized in this article.

Guideline-directed medical therapy in patients undergoing transcatheter edge-to-edge repair for secondary mitral regurgitation

AIMS

Guideline-directed medical therapy (GDMT), based on the combination of beta-blockers (BB), renin-angiotensin system inhibitors (RASI), and mineralocorticoid receptor antagonists (MRA), is known to have a major impact on the outcome of patients with heart failure with reduced ejection fraction (HFrEF). Although GDMT is recommended prior to mitral valve transcatheter edge-to-edge repair (M-TEER), not all patients tolerate it. We studied the association of GDMT prescription with survival in HFrEF patients undergoing M-TEER for secondary mitral regurgitation (SMR).

METHODS AND RESULTS

EuroSMR, a European multicentre registry, included SMR patients with left ventricular ejection fraction <50%. The outcome was 2-year all-cause mortality. Of 1344 patients, BB, RASI, and MRA were prescribed in 1169 (87%), 1012 (75%), and 765 (57%) patients at the time of M-TEER, respectively. Triple GDMT prescription was associated with a lower 2-year all-cause mortality compared to non-triple GDMT (hazard ratio [HR] 0.74; 95% confidence interval [CI] 0.60-0.91). The association persisted in patients with glomerular filtration rate <30 ml/min, ischaemic aetiology, or right ventricular dysfunction. Further, a positive impact of triple GDMT prescription on survival was observed in patients with residual mitral regurgitation of ≥2+ (HR 0.62; 95% CI 0.44-0.86), but not in patients with residual mitral regurgitation of ≤1+ (HR 0.83; 95% CI 0.64-1.08).

CONCLUSION

Triple GDMT prescription is associated with higher 2-year survival after M-TEER in HFrEF patients with SMR. This association was consistent also in patients with major comorbidities or non-optimal results after M-TEER.

Acute effect of edge-to-edge repair of mitral regurgitation on left heart mechanics and health status

AIMS

Examine the impact of acute changes in left heart strain and volumes with percutaneous edge-to-edge MitraClip repair on improvement in health status assessed using Kansas City Cardiomyopathy Questionnaire-12 (KCCQ-12) score.

METHODS

Changes in left atrial strain, left ventricular (LV) global longitudinal strain (LVGLS), LV end-systolic volume (LVESV), and end-diastolic volume (LVEDV) were evaluated in 50 patients undergoing MitraClip repair for symptomatic primary mitral regurgitation (PMR) and secondary mitral regurgitation (SMR) on transthoracic echocardiography before and 1 month after MitraClip. Multivariable regression was used to evaluate changes in left heart strain and volumes as predictors of change in KCCQ-12 scores, adjusting for baseline clinical and echocardiographic characteristics.

RESULTS

Both PMR and SMR patients had significant increase in LVGLS and reduction in LVEDV and LVESV (P < 0.05) after MitraClip, reduction trend in left atrial conduit strain (PMR P = 0.053; SMR P = 0.12) but no significant change in LV ejection fraction. KCCQ-12 score improved significantly in both PMR (P < 0.001) and SMR cohorts (P < 0.001). Higher delta KCCQ-12 tertiles were associated with greater reduction in LVEDV (P = 0.022) after MitraClip. On multiple regression analysis, lower preprocedural Society of Thoracic Surgeons for Mitral Valve Replacement and KCCQ-12 score, and greater reduction in LVESV and left atrial strain conduit phase were associated with KCCQ-12 score improvement (P < 0.001).

CONCLUSION

There is a significant increase in LVGLS and reduction in LVEDV, LVESV and left atrial strain conduit after edge-to-edge MitraClip repair in both PMR and SMR. Lower preprocedural Society of Thoracic Surgeons for Mitral Valve Replacement and KCCQ-12 score, and greater reduction in LVESV and left atrial conduit strain were associated with KCCQ-12 score improvement after MitraClip. Further studies are warranted to understand the mechanism and significance of our findings.

Myocardial work: the analytical methodology and clinical utilities

The evaluation of left ventricular (LV) systolic function is an essential part of the clinical practice of cardiology. Although left ventricular ejection fraction (LVEF) is the most validated and widely used parameter, it has fundamental limitations. LV strain is more sensitive to detect subtle myocardial dysfunction when LVEF was preserved, but it is load-dependent. Invasive left ventricular pressure-volume loop (LV-PVL) is the reliable standard to evaluate cardiac function, but its wide clinical application is limited by the risk of invasive LV pressure detection. Until the advent of non-invasive LV pressure-strain loop (LV-PSL), things have changed. LV-PSL is in good agreement with regional myocardial oxygen consumption and metabolism. Compared with traditional echocardiographic parameters or LV strain, myocardial work (MW) derived from LV-PSL is a more advanced tool that combines deformation as well as hemodynamics through integration of global longitudinal strain and non-invasive LV systolic pressure. In recent years, researches on MW are going on in full swing and show many advantages of MW. This review described the method and discussed the applications, advantages, limitations, and prospects of MW in multiple cardiovascular diseases. The goal is to provide the readers new insights for evaluating LV systolic function and promote the incorporation of MW into daily practice.

Relation of Myocardial Work Indexes and Forward Flow Reserve in Patients With Significant Secondary Mitral Regurgitation Undergoing Transcatheter Mitral Valve Repair

Left ventricular (LV) myocardial work (LVMW) indexes have shown incremental value over LV ejection fraction and were found to have prognostic significance in patients with secondary mitral regurgitation. We therefore aimed to investigate the association between LVMW indexes and forward flow reserve in patients with secondary mitral regurgitation, treated with transcatheter edge-to-edge repair (TEER). LVMW indexes were evaluated at baseline and forward stroke volume index (FSVI) was evaluated at baseline and 6-month follow-up after TEER. Patients were divided in 2 groups: improvers (improvement in FSVI ≥20%) and nonimprovers (improvement in FSVI <20%). A total of 70 patients (median age 76 years, 59% men) were included. FSVI was the only echocardiographic parameter that improved after TEER. There was a significant decrease in LV global longitudinal strain in the nonimprovers (p = 0.002) but not in the improvers (p = 0.177). Global work index and global constructive work worsened in nonimprovers (p = 0.005 and p = 0.004, respectively), whereas no difference was seen in these indexes in improvers (p = 0.093 and p = 0.112, respectively). Global work efficiency remained independently associated with forward flow reserve after adjusting for a variety of potential confounders. In conclusion, FSVI nonimprovers demonstrated worsening of LV systolic function after TEER compared with improvers, in whom LV systolic function remained stable. Global work efficiency was associated with FSVI improvement after TEER, independent of LV systolic function.

Global longitudinal strain and outcome after endoscopic mitral valve repair

Aims

Identification of heart failure (HF) patients with secondary mitral regurgitation (SMR) that benefit from mitral valve (MV) repair remains challenging. We have focused on the role of left ventricular global longitudinal strain (LV‐GLS) and reservoir left atrial longitudinal strain (LASr) for the prediction of long‐term survival and reverse remodelling in patients with SMR undergoing endoscopic MV repair.

Methods and results

The study population consisted of 110 patients (age 67 ± 11 years, 66% men) with symptomatic SMR undergoing isolated MV repair using a minimally invasive surgical approach. Speckle tracking‐derived LV‐GLS and LASr were assessed in apical views using vendor‐independent software. Over a median of 7.7 years (IQRs 2.9–11.2), 64 patients (58%) died. Significant reverse LV (↓ LVESVI >10 mL/m²), LA (↓ LAVI >10 mL/m²) remodelling or both were observed in 43 (39%), 37 (34%) and 19 (17%) patients, respectively. LV‐GLS (HR 0.68, 95% CI 0.58–0.79, P < 0.001) and LASr (HR 0.93, 95% CI 0.88–0.97, P < 0.01) but not LV ejection fraction (LVEF) and LA volume index (LAVi) emerged as independent predictors of all‐cause mortality in Cox regression analysis. LV‐GLS was the only independent predictor of LV reverse remodelling (OR 1.24, 95% CI 1.05–1.43, P < 0.001) whereas LAVi and LASr were both independent predictors of LA reverse remodelling (both P < 0.05). In patients with atrial fibrillation at baseline, only LASr was an independent predictor (P < 0.05) of LA reverse remodelling.

Conclusions

In patients with SMR undergoing endoscopic MV repair, LV‐GLS and LASr are independently associated with long‐term survival and reverse remodelling and may be helpful in selecting SMR patients who may benefit from this procedure.

Left ventricular reverse remodelling and its predictors in non-ischaemic cardiomyopathy

Adverse remodelling following an initial insult is the hallmark of heart failure (HF) development and progression. It is manifested as changes in size, shape, and function of the myocardium. While cardiac remodelling may be compensatory in the short term, further neurohumoral activation and haemodynamic overload drive this deleterious process that is associated with impaired prognosis. However, in some patients, the changes may be reversed. Left ventricular reverse remodelling (LVRR) is characterized as a decrease in chamber volume and normalization of shape associated with improvement in both systolic and diastolic function. LVRR might occur spontaneously or more often in response to therapeutic interventions that either remove the initial stressor or alleviate some of the mechanisms that contribute to further deterioration of the failing heart. Although the process of LVRR in patients with new‐onset HF may take up to 2 years after initiating treatment, there is a significant portion of patients who do not improve despite optimal therapy, which has serious clinical implications when considering treatment escalation towards more aggressive options. On the contrary, in patients that achieve delayed improvement in cardiac function and architecture, waiting might avoid untimely implantable cardioverter‐defibrillator implantation. Therefore, prognostication of successful LVRR based on clinical, imaging, and biomarker predictors is of utmost importance. LVRR has a positive impact on prognosis. However, reverse remodelled hearts continue to have abnormal features. In fact, most of the molecular, cellular, interstitial, and genome expression abnormalities remain and a susceptibility to dysfunction redevelopment under biomechanical stress persists in most patients. Hence, a distinction should be made between reverse remodelling and true myocardial recovery. In this comprehensive review, current evidence on LVRR, its predictors, and implications on prognostication, with a specific focus on HF patients with non‐ischaemic cardiomyopathy, as well as on novel drugs, is presented.

The non-invasive assessment of myocardial work by pressure-strain analysis: clinical applications

Pressure–volume (PV) analysis is the most comprehensive way to describe cardiac function, giving insights into cardiac mechanics and energetics. However, PV analysis still remains a highly invasive and time-consuming method, preventing it from integration into clinical practice. Most of the echocardiographic parameters currently used in the clinical routine to characterize left ventricular (LV) systolic function, such as LV ejection fraction and LV global longitudinal strain, do not take the pressure developed within the LV into account and therefore fall too short in describing LV function as a hydraulic pump. Recently, LV pressure-strain analysis has been introduced as a new technique to assess myocardial work in a non-invasive fashion. This new method showed new insights in comparison to invasive measurements and was validated in different cardiac pathologies, e.g., for the detection of coronary artery disease, cardiac resynchronization therapy (CRT)-response prediction, and different forms of heart failure. Non-invasively assessed myocardial work may play a major role in guiding therapies and estimating prognosis. However, its incremental prognostic validity in comparison to common echocardiographic parameters remains unclear. This review aims to provide an overview of pressure-strain analysis, including its current application in the clinical arena, as well as potential fields of exploitation.

Left Ventricular Global Longitudinal Strain as a Predictor of Outcomes in Patients with Heart Failure with Secondary Mitral Regurgitation: The COAPT Trial

BACKGROUND

Left ventricular (LV) global longitudinal strain (GLS) is a sensitive marker of LV function and may help identify patients with heart failure (HF) and secondary mitral regurgitation who would have a better prognosis and are more likely to benefit from edge-to-edge transcatheter mitral valve repair with the MitraClip. The aim of this study was to assess the prognostic utility of baseline LV GLS during 2-year follow-up of patients with HF with secondary mitral regurgitation enrolled in the Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients with Functional Mitral Regurgitation trial.

METHODS

Patients with symptomatic HF with moderate to severe or severe secondary mitral regurgitation who remained symptomatic despite maximally tolerated guideline-directed medical therapy (GDMT) were randomized to transcatheter mitral valve repair plus GDMT or GDMT alone. Speckle-tracking-derived LV GLS from baseline echocardiograms was obtained in 565 patients and categorized in tertiles. Death and HF hospitalization at 2-year follow-up were the principal outcomes of interest.

RESULTS

Patients with better baseline LV GLS had higher blood pressure, greater LV ejection fraction and stroke volume, lower levels of B-type natriuretic peptide, and smaller LV size. No significant difference in outcomes at 2-year follow-up were noted according to LV GLS. However, the rate of death or HF hospitalization between 10 and 24 months was lower in patients with better LV GLS (P = .03), with no differences before 10 months. There was no interaction between GLS tertile and treatment group with respect to 2-year clinical outcomes.

CONCLUSIONS

Baseline LV GLS did not predict death or HF hospitalization throughout 2-year follow-up, but it did predict outcomes after 10 months. The benefit of transcatheter mitral valve repair over GDMT alone was consistent in all subgroups irrespective of baseline LV GLS.

Myocardial work index: a marker of left ventricular contractility in pressure- or volume overload-induced heart failure

Aims

While global longitudinal strain (GLS) is considered to be a sensitive marker of left ventricular (LV) function, it is significantly influenced by loading conditions. We hypothesized that global myocardial work index (GMWI), a novel marker of LV function, may show better correlation with load‐independent markers of LV contractility in rat models of pressure‐induced or volume overload‐induced heart failure.

Methods and results

Male Wistar rats underwent either transverse aortic constriction (TAC; n = 12) or aortocaval fistula creation (ACF; n = 12), inducing LV pressure or volume overload, respectively. Sham procedures were performed to establish control groups (n = 12/12). Echocardiographic loops were obtained to determine GLS and GMWI. Pressure‐volume analysis with transient occlusion of the inferior caval vein was carried out to calculate preload recruitable stroke work (PRSW), a load‐independent ‘gold‐standard’ parameter of LV contractility. Myocardial samples were collected to assess interstitial and perivascular fibrosis area and also myocardial atrial‐type natriuretic peptide (ANP) and brain‐type natriuretic peptide (BNP) relative mRNA expression. Compared with controls, GLS was substantially lower in the TAC group (−7.0 ± 2.8 vs. −14.5 ± 2.5%; P < 0.001) and was only mildly reduced in the ACF group (−13.2 ± 2.4 vs. −15.4 ± 2.0%, P < 0.05). In contrast with these findings, PRSW and GMWI were comparable with sham in TAC (110 ± 26 vs. 116 ± 68 mmHg; 1687 ± 275 mmHg% vs. 1537 ± 662 mmHg%; both P = NS), while it was found to be significantly reduced in ACF (58 ± 14 vs. 111 ± 40 mmHg; 1328 ± 411 vs. 1934 ± 308 mmHg%, both P < 0.01). In the pooled population, GMWI (r = 0.70; P < 0.001) but not GLS (r = −0.23; P = 0.12) showed a strong correlation with PRSW. GLS correlated with interstitial (r = 0.61; P < 0.001) and perivascular fibrosis area (r = 0.54; P < 0.001), and also with myocardial ANP (r = 0.85; P < 0.001) and BNP relative mRNA expression (r = 0.75; P < 0.001), while GMWI demonstrated no or only marginal correlation with these parameters.

Conclusions

Being significantly influenced by loading conditions, GLS may not be a reliable marker of LV contractility in heart failure induced by pressure or volume overload. GMWI better reflects contractility in haemodynamic overload states, making it a more robust marker of systolic function, while GLS should be considered as an integrative marker, incorporating systolic function, haemodynamic loading state, and adverse tissue remodelling of the LV.

Myocardial Work: Methodology and Clinical Applications

A precise and accurate assessment of left ventricular (LV) contractility is of utmost importance in terms of prognosis in most cardiac pathologies. Given the limitations of ejection fraction (EF) and global longitudinal strain (GLS) due to their load dependency, a novel imaging tool called myocardial work (MW) has emerged as a promising method for LV performance evaluation. MW is a novel, less load-dependent method based on computation of myocardial strain-arterial blood pressure curves. This method provides a more detailed assessment of segmental and global LV function incorporating the patient's LV pressure and is derived by brachial artery pressure utilizing an empiric reference curve adjusted to the duration of the isovolumic and ejection phases as determined by echocardiography. The clinical implications of this unique method have been expanding in the last few years, which attest to the robust additive role of MW in routine practice.

Transcatheter Repair of the Mitral Valve: Relevant Pathophysiology, Investigation, and Management

Mitral regurgitation (MR) is a common condition causing significant morbidity and mortality in the Western world. Although surgical therapy has developed over 5 decades to provide solutions, only a minority of patients undergo surgery. The last decade has seen the emergence and application of multiple transcatheter techniques in attempts to address this undertreated population with the large clinical experience of MitraClip providing the most insight. Clear understanding of the pathophysiology of different MR types as well as the role of particularly secondary MR on patient's clinical syndrome allow for better prediction as to which patient subgroups will benefit from different repair techniques or intervention at all. Most of the techniques are based on surgical technique and are applied as single-device/technique solutions, whether leaflet, chordal, or annular solutions, but with broadening experience, combination therapies are likely to find a place in creating a more complete and surgical-like solution.

MitraClip and left ventricular reverse remodelling: a strain imaging study

AIMS

The purpose of this study is to identify echocardiography predictors of clinical response and reverse left ventricular (LV) remodelling in patients with functional mitral regurgitation (FMR) treated with MitraClip.

METHOD AND RESULTS

We retrospectively analysed 86 high surgical risk patients with severe FMR; of those, 58 were implanted a MitraClip, and 28 received medical treatment and served as controls. At baseline and at 1-year follow-up, we performed clinical and echocardiography evaluation to assess global longitudinal strain (GLS) and myocardial work [global work index (GWI), global constructive work (GCW), global wasted work (GWW), global work efficiency (GWE)]. Mitral regurgitation was significantly reduced after MitraClip implantation (3.7 ± 0.4 vs. 1.7 ± 0.8, P < 0.001), and the procedure was associated with improvement in brain natriuretic peptide levels (980 ± 1027 vs. 420 ± 338 pg/mL, P < 0.001), New York Heart Association class status (3.2 ± 0.55 vs. 2.0 ± 0.6, P < 0.001), 6-min walking test (233 ± 154 vs. 286 ± 114 m, P = 0.01) at follow-up and reduction of left ventricle end-systolic (LVESV) and left ventricle end-diastolic volumes (LVEDV) (152 ± 68 vs. 136 ± 43 mL, P = 0.004 & 219 ± 74 vs. 193 ± 66 mL, P = 0.001, respectively). MitraClip procedure was associated with improvement of LV performance and significant increase of GWI (607 ± 282 vs. 650 ± 260 mmHg%, P = 0.045) and GCW (854 ± 288 vs. 949 ± 325 mmHg%, P < 0.001). Baseline ejection fraction (EF), GLS, GWI, GCW, and effective regurgitant orifice area were the variables that were associated with reduction of LVEDV 1 year after intervention (P < 0.05 for all) and baseline GCW of the LV was the only variable associated with reduction of LVESV (P = 0.002). Receiver operating characteristic curve analysis identified that a GLS cut-off value of -8.65% (AUC 0.815, P = 0.007) was associated with a 20% reduction of the LVEDV with a sensitivity and specificity of 72% and 70%, respectively, and that a GCW cut-off value of 846 mmHg% (AUC 0.759, P = 0.007) was associated with a 10% reduction of LVESV with sensitivity and specificity 79% and 74%, respectively.

CONCLUSIONS

Mitral valve repair with MitraClip has positive clinical and echocardiographic impact in patients with FMR 1 year after implantation. Preserved GLS and GCW values appear to be associated with LV reverse remodelling post intervention.