Myocardial recovery and the failing heart: myth, magic, or molecular target?

Characteristics, outcomes and the necessity of continued guideline-directed medical therapy in patients with heart failure with improved ejection fraction

BACKGROUND

Much remains to be learned about patients with heart failure with improved ejection fraction (HFimpEF).

OBJECTIVE

This study sheds light on the characteristics and clinical outcomes of HFimpEF patients, including the consequences of halting guideline-directed medical therapy (GDMT).

METHODS

This retrospective study was conducted on patients diagnosed with heart failure with reduced ejection fraction (HFrEF) who underwent a second echocardiogram at least 6 months apart between January 2009 and February 2023. The primary outcomes were major adverse cardiovascular events (MACEs), including all-cause mortality and heart failure hospitalization. The second outcome was recurrent HFrEF.

RESULTS

Of 4,560 HFrEF patients were included, 3,289 (72.1%) achieved HFimpEF within a median follow-up period of 3.4 years (IQR: 1.8 - 5.9 years). Among these HFimpEF patients, recurrent HFrEF was observed in 941 (28.6%) patients during a median follow-up period of 2.3 years (IQR: 0.8-4.6 years). The proportion of patients who halted GDMT was 70.4%, 53.2%, 59.8% and 63.8% for MRA, beta-blockers, ACEI/ARB/ARNI and SGLT-2 inhibitors. Multivariable Cox analysis revealed ischemic heart disease, chronic kidney disease, coronary heart disease, lower left ventricular ejection fraction, larger left ventricular diastolic dimension and non-use GDMT are associated with recurrent HFrEF. Individuals without GDMT use exhibited lower chances of persistently recovering ejection fraction and high risks of MACEs compared to those who continue use.

CONCLUSIONS

HFimpEF is a common condition across all clinical follow-ups. Prevalent discontinuation of GDMT medications may contribute significantly to recurrent HFrEF, placing patients at a higher risk for poor prognosis.

Finerenone in Heart Failure With Improved Ejection Fraction: The FINEARTS-HF Randomized Clinical Trial

Importance

Patients with chronic heart failure (HF) and left ventricular ejection fraction (LVEF) less than 40% who experience LVEF improvement to 40% or higher (HFimpEF) may still face residual risks.

Objective

To assess the clinical profiles, risk, and treatment response to finerenone in participants with HFimpEF.

Design, Setting, and Participants

A total of 6001 patients with HE, LVEF of 40% or higher, New York Heart Association class II to IV symptoms, and elevated natriuretic peptide levels, were enrolled between September 14, 2020, and January 10, 2023. Patients with a prior history of LVEF less than 40% were included. Data analysis was conducted between September 1 to December 10, 2024.

Intervention

Participants received finerenone (titrated to 20 mg or 40 mg) or placebo.

Main Outcomes and Measures

The primary end point was the composite of cardiovascular (CV) death and total (first and recurrent) worsening HF events.

Results

Of the 6001 participants (mean [SD] age, 72 [9.7], years; 3269 male [55%]), 273 (5%) had a prior LVEF less than 40%. Among those with a prior LVEF of less than 40%, the median recorded prior LVEF was 35% [IQR, 30%-37%], with a median improvement of 12% [IQR, 8%-17%]. Over a median follow-up of 2.6 years, those with a history of LVEF of less than 40% experienced higher rates of the primary outcome of a composite of CV death and worsening of HF events (21.4 per 100 patient-years vs 16.0 per 100 patient-years) than did those whose LVEF was consistently 40% or higher. After adjustment for clinically relevant covariates; however, this rate ratio (RR) was not statistically different (absolute RR, 1.13; 95% CI, 0.85-1.49, P = .39). The treatment effect of finerenone on the primary outcome was consistent among those with a history of LVEF less than 40% and those with LVEF that was consistently 40% or higher (P for interaction = .36). Owing to higher baseline risk, the absolute risk reduction was greater among those with HFimpEF (9.2 vs 2.5 per 100 patient-years). Patients with HFimpEF tended to develop more hypotension with finerenone treatment, but otherwise, the safety profile of finerenone was similar in patients with and without previous LVEF less than 40%.

Conclusions and Relevance

In this prespecified analysis of a randomized clinical trial, patients with HFimpEF remained at high risk of CV events, underscoring the need for continued management despite LVEF improvement. The treatment benefits of finerenone observed among the overall population of patients with HF with preserved EF were consistent among patients with HFimpEF.

Trial Registration

ClinicalTrials.gov Identifier: NCT04435626.

Early Left Ventricular Reverse Remodeling After Catheter Ablation of Atrial Fibrillation is Associated With Lower Recurrence Rates and Improved Prognosis in Patients With Left Ventricular Systolic Dysfunction

INTRODUCTION

Left ventricular (LV) reverse remodeling (LVRR) following catheter ablation (CA) of atrial fibrillation (AFCA) has not been fully elucidated. This study investigated the clinical impact of early LVRR after AFCA on prognosis in patients with LV systolic dysfunction (LVSD).

METHODS

Of 1,989 consecutive patients undergoing first-time AFCA, 302 patients with a baseline LV ejection fraction < 50% were included. LVRR was defined as a decrease in the LV end-systolic volume of ≥ 15% on an echocardiography at 3 months after AFCA. The clinical outcomes and prognoses were compared between patients with and without LVRR.

RESULTS

LVRR was observed in 191 (63%) patients at 3 months after AFCA. A multiple logistic regression analysis demonstrated that non-paroxysmal AF, non-cardiomyopathy, absence of early recurrence, QRS duration ≤ 120 ms were significantly associated with the LVRR after 3 months. During a median follow-up period of 30 (16-50) months, patients with LVRR showed a lower incidence of AF recurrence (24.1% vs. 39.6%; p = 0.004), heart failure hospitalizations (5.8% vs. 13.5%; p = 0.022), all-cause mortality (4.2% vs. 11.7%; p = 0.017), and composite events including recurrence, heart failure hospitalization, and mortality (26.7% vs. 48.7%; p < 0.001) compared to those without. A multivariate Cox regression analysis revealed that the LVRR at 3 months was independently associated with AF recurrence-free survival (hazard ratio, 0.624, p = 0.029) and composite endpoint (hazard ratio, 0.573, p = 0.006) after AFCA.

CONCLUSIONS

The LVRR emerged in two-third of the patients with LVSD after 3 months of AFCA. Early LVRR was associated with favorable clinical outcomes and prognoses after AFCA.

An interpretable radiomics-based machine learning model for predicting reverse left ventricular remodeling in STEMI patients using late gadolinium enhancement of myocardial scar

OBJECTIVES

To evaluate the added value of the late gadolinium enhancement (LGE)-scar radiomics features in predicting reverse left ventricular remodeling (r-LVR) in ST-segment elevation myocardial infarction (STEMI) patients using machine learning (ML).

MATERIALS AND METHODS

This retrospective study included 105 STEMI patients who underwent CMR within 7 days and 5 months post-percutaneous coronary intervention (PCI) on 1.5-T or 3.0-T MRI scanners (January 2014-2023). Radiomics features from LGE scar images and routine CMR markers were analyzed using a LightGBM model enhanced by Shapley Additive exPlanations (SHAP) for interpretability. Patients were divided into training (80) and test (25) sets. Three predictive models were developed: traditional CMR, LGE-scar radiomics, and a combined model integrating both. Model performance was assessed using ROC curves and AUC analysis.

RESULTS

In the training set, the traditional CMR model achieved an AUC of 0.745 (95% CI: 0.62-0.86), the LGE-scar radiomics model had an AUC of 0.712 (95% CI: 0.58-0.83), and the combined model showed the highest AUC of 0.754 (95% CI: 0.63-0.86). In the test set, the traditional CMR model's AUC decreased to 0.656 (95% CI: 0.42-0.88), while the LGE-scar radiomics model improved to 0.818 (95% CI: 0.59-1.00). The combined model achieved the highest AUC of 0.890 (95% CI: 0.75-1.00). SHAP analysis highlighted significant predictors such as infarct percentage of LV mass and wavelet-transformed texture features.

CONCLUSION

Integrating LGE scar radiomics features with traditional CMR parameters in a LightGBM model enhances predictive accuracy for r-LVR in STEMI patients, potentially improving patient stratification and treatment personalization.

KEY POINTS

Question Predicting r-LVR in STEMI patients remains challenging due to limitations in current imaging approaches. Findings Integrating LGE-scar radiomics and cardiac magnetic resonance markers in the LightGBM model significantly improves prediction accuracy for r-LVR. Clinical relevance This interpretable ML model enhances r-LVR prediction, supporting patient stratification and optimizing treatment strategies to improve patient outcomes.

Transvalvular Mechanical Circulatory Support Reverse Remodels the Ischemic Chronic Failing Heart in an Ovine Model

Sixteen sheep with ischemic chronic heart failure were randomized to either 3 months of Impella 5.5 support (Abiomed) or sham. Myocardial reverse remodeling by Impella support was shown by a significant reduction of end-diastolic volume (Impella 22% reduction, and control 5% increase; P = 0.011) and end-systolic volume (Impella 20% reduction, and control 11% increase; P = 0.011). Functional measurements demonstrated improved regional ejection fraction and wall thickening in the viable myocardium of hearts supported with Impella. Supported animals had a significant decrease in wall volume, with less cardiomyocyte hypertrophy than control subjects.

Effects of Rhythm Control for Atrial Fibrillation on Cardiac Remodeling and Valvular Regurgitation in Patients with Heart Failure

PURPOSE

Previous studies investigating cardiac remodeling and functional regurgitation of rhythm control for atrial fibrillation (AF) in heart failure (HF) are limited. Therefore, this study aimed to evaluate the impact of rhythm control for AF on cardiac remodeling and functional regurgitation in the spectrum of HF. Its effect on prognosis was explored.

METHODS

According to the treatment strategies of AF, the cohort was classified into the rhythm control and rate control groups. To further detect the implications of rhythm control on cardiac remodeling, functional regurgitation, and outcomes in HF subtypes, patients were further divided into HF with reduced ejection fraction (HFrEF), HF with mildly reduced ejection fraction, and HF with preserved ejection fraction (HFpEF) subgroups.

RESULTS

A total of 828 patients were enrolled, with 307 patients in the rhythm control group and 521 patients in the rate control group. Over a median follow-up time of 3.8 years, patients with rhythm control treatments experienced improvements in biatrial structure parameters, left ventricular ejection fraction, and functional regurgitation (mitral and tricuspid regurgitation) compared with rate control treatment (p < 0.05). Cox regression analysis demonstrated that rhythm control reduced the risks of all-cause mortality (HR 0.436 [95% CI, 0.218-0.871], p = 0.019) in HFpEF and HF-related admissions in HFrEF (HR 0.500 [95% CI, 0.330-0.757], p = 0.001) and HFpEF (HR 0.541 [95% CI, 0.407-0.720], p < 0.001); these associations were similar after adjusting for multiple confounders.

CONCLUSIONS

Rhythm control therapy can be considered an appropriate treatment strategy for the management of AF in HF to improve cardiac remodeling, functional regurgitation, and prognosis.

Cardiovascular Effects of Increasing Positive End-expiratory Pressure in a Model of Left Ventricular Cardiogenic Shock in Female Pigs

BACKGROUND

Cardiogenic shock (CS) presents a medical challenge with limited treatment options. Positive end-expiratory pressure (PEEP) during mechanical ventilation has been linked with clinical benefits in patients with CS. This study investigated whether increasing PEEP levels could unload the left ventricle (LV) in CS in a large animal model of LV-CS.

METHODS

Left ventricle cardiogenic shock was induced in 26 female pigs (60 kg) by microsphere injections into the left main coronary artery. In one study, protocol PEEP was increased (5, 10, and 15 cm H2O) and then reverted (15, 10, and 5 cm H2O) in 3-min intervals. In another protocol, PEEP increments with higher granularity were conducted through 3-min intervals (5, 8, 10, 13, and 15 cm H2O). Hemodynamic measurements were performed at all PEEP levels during a healthy state and in LV-CS with LV pressure-volume loops. The primary endpoint was pressure-volume area. Secondary endpoints included other mechanoenergetic parameters and estimates of LV preload and afterload.

RESULTS

Cardiac output (CO) decreased significantly in LV-CS from 4.5 ± 1.0 to 3.1 ± 0.9 l/min (P < 0.001). Increasing PEEP resulted in lower pressure-volume area, demonstrating a 36 ± 3% decrease in the healthy state (P < 0.001) and 18 ± 3% in LV-CS (P < 0.001) at PEEP 15 cm H2O. These effects were highly reversible when PEEP was returned to 5 cm H2O. Although mean arterial pressure declined with higher PEEP, CO remained preserved during LV-CS (P = 0.339). Increasing PEEP caused reductions in key measures of LV preload and afterload during LV-CS. The right ventricular stroke work index was decreased with increased PEEP. Despite a minor increase in heart rate at PEEP levels of 15 cm H2O (71 beats/min vs. 75 beats/min, P < 0.05), total mechanical power expenditure (pressure-volume area normalized to heart rate) decreased at higher PEEP.

CONCLUSIONS

Applying higher PEEP levels reduced pressure-volume area, preserving CO while decreasing mean arterial pressure. Positive end-expiratory pressure could be a viable LV unloading strategy if titrated optimally during LV-CS.

EDITOR’S PERSPECTIVE

Dynamic trajectories of left ventricular ejection fraction in heart failure with improved ejection fraction

BACKGROUND

Heart failure with improved ejection fraction (HFimpEF) has been regarded as a new heart failure (HF) type in 2022. However, studies on the impact of left ventricular ejection fraction (LVEF) trajectories on the prognosis of patients with HFimpEF are scarce. In this study, we investigated dynamic trajectories of LVEF and different clinical outcomes in HFimpEF.

METHODS AND RESULTS

This was a multi-center study included patients diagnosed with HF with reduced ejection fraction (HFrEF) between January 1, 2015, and October 31, 2022. Enrolled patients were divided into HFimpEF and persistent HFrEF groups. To further investigate different LVEF trajectories in HFimpEF patients, they were classified into persistent HFimpEF and transient HFimpEF subgroups. Adverse clinical outcomes encompassed all-cause death, cardiovascular death, and HF-related rehospitalization. A total of 734 patients were included (HFimpEF: n = 162; persistent HFrEF: n = 572). Cox regression analysis revealed that compared with persistent HFrEF, patients with HFimpEF experienced a lower risk of all-cause and cardiovascular death. Subgroup analysis determined that only 113 (69.75%) patients maintained an LVEF exceeding 40%. Cox regression analysis revealed that persistent HFimpEF patients had a lower risk of all-cause and cardiovascular death compared to those with transient HFimpEF. Finally, multivariate logistic analysis showed that gender and high-density lipoprotein cholesterol levels were independent predictors of persistent HFimpEF.

CONCLUSIONS

HFimpEF does not accurately represent HF recovery, given that there are different trajectories of LVEF in HFimpEF. Patients with persistent HFimpEF experience better clinical outcomes, highlighting clinicians should identify clinical modifiable factors to maintain a stable HF stage for better prognosis.

TRIAL REGISTRATION

ChiCTR2400086622, 08/07/2024.

Prognosis After Withdrawal of Cardioprotective Therapy in Patients With Improved Cancer Therapeutics-Related Cardiac Dysfunction

Background

The long-term prognosis after the discontinuation of cardioprotective therapy (CPT) in patients with cancer therapeutics-related cardiac dysfunction (CTRCD) that has shown improvement remains unclear.

Objectives

This study aims to assess the prognosis after CPT withdrawal in patients exhibiting improved CTRCD.

Methods

In this retrospective analysis of a single-center prospective cohort study, patients with improved CTRCD, defined as an increase in left ventricular ejection fraction (LVEF) ≥10 percentage points from the time of CTRCD diagnosis, were included. We analyzed their clinical outcomes, which included hospitalization for heart failure or a decrease in LVEF ≥10 percentage points within 2 years after CTRCD improvement, alongside echocardiographic changes.

Results

The cohort comprised 134 patients with improved CTRCD. The median follow-up duration after CTRCD diagnosis was 368.3 days (Q1-Q3: 160-536 days). After improvement, 90 patients continued CPT (continued group [CG]) and 44 withdrew CPT (withdrawn group [WG]). Among patients whose baseline LVEF at CTRCD diagnosis ranged from 45% to 55%, the final mean LVEF was comparable between both groups (CG: 64.9% ± 4.4% vs WG: 62.9% ± 4.2%; P = 0.059). However, for patients with a baseline LVEF <45%, the final mean LVEF was significantly lower in the WG (CG: 53.3% ± 6.4% vs WG: 48.2% ± 6.9%; P < 0.001). The occurrence of composite major clinical events was notably higher in the WG (HR: 3.06; 95% CI: 1.51-7.73; P = 0.002).

Conclusions

Patients who withdrew CPT after demonstrating improvement in CTRCD experienced worse clinical outcomes. Notably, a significant decrease in LVEF was observed after CPT withdrawal in patients with a baseline LVEF <45%.

Recovery From Left Ventricular Dysfunction

The treatment of heart failure is an evolving field of cardiology, with increasingly available therapeutics and significant disease burden. With the effective treatments available, we see a substantial patient population whose once reduced ejection fraction (EF) has normalized. Studies have assessed the natural history of these patients with improved EF and found improved mortality as compared with those patients with persistently reduced EF, with some evidence stating that each 5% increase in left ventricular EF correlates with a 4.9-fold decrease in the odds of mortality. This prognostic divergence has led to the recognition of this subset of patients as having a unique heart failure diagnosis, distinct from heart failure with reduced EF (HFrEF) or heart failure with preserved EF and to the adoption of the term heart failure with recovered EF. These patients, despite having improved mortality, do retain some of the molecular and histologic changes seen in HFrEF and are still at risk for decline in left ventricular function and adverse cardiac events, particularly when medical therapy is stopped. This distinction between recovery of EF and true myocardial recovery led to recent guidelines recommending continuation of guideline-directed medical therapy indefinitely, as well as surveillance echocardiography.

Myocardial Recovery versus Myocardial Regeneration: Mechanisms and Therapeutic Modulation

Myocardial recovery is characterized by a return toward normal structure and function of the heart after an injury. Mechanisms of myocardial recovery include restoration and/or adaptation of myocyte structure and function, mitochondrial activity and number, metabolic homeostasis, electrophysiological stability, extracellular matrix remodeling, and myocardial perfusion. Myocardial regeneration is an element of myocardial recovery that involves the generation of new myocardial tissue, a process which is limited in adult humans but may be therapeutically augmented. Understanding the mechanisms of myocardial recovery and myocardial regeneration will lead to novel therapies for heart failure.

Myocardial Recovery in Cardiogenic Shock

The overarching goal of cardiogenic shock (CS) therapy is ensuring long-term survival. In recent years, increasing emphasis has been placed on analyzing mechanisms to improve outcomes in CS. This includes averting in-hospital mortality, modifying the disease process by promoting heart recovery while avoiding multiorgan failure, and circumventing complications related to both CS and treatment strategies deployed to treat CS. Heart replacement therapies represent a viable strategy for long-term survival but are restricted to a small, select percentage of patients. In this review we focus on pathophysiology of the shock state, with an emphasis on addressing reversible etiologies contributing to the decompensated state, optimizing physiological factors for recovery, and identifying therapeutic targets to promote recovery. We also review the known predictors of myocardial recovery, regardless of the etiology of CS. Lastly, we highlight the current gaps in knowledge in this field and support additional high-quality studies focusing on myocardial recovery in CS.

The Pathobiology of Myocardial Recovery and Remission: From Animal Models to Clinical Observations in Heart Failure Patients

Heart failure with reduced left ventricular (LV) ejection fraction (HFrEF) is a morbid and life-threatening disease, arising secondary to abnormalities of cardiac structure and function that lead to adverse LV remodeling. Implementation of medical and device therapies results in significant improvements in patient outcomes that are associated with reverse LV remodeling and improved LV ejection fraction. This review provides an overview of the pathobiology of reverse LV remodeling in animal models and in HFrEF patients. We emphasize the differences between myocardial recovery and remission as well as the fragile nature of maintaining a state of myocardial remission.

Role of Artificial Intelligence and Machine Learning to Create Predictors, Enhance Molecular Understanding, and Implement Purposeful Programs for Myocardial Recovery

Heart failure (HF) affects millions of individuals and causes hundreds of thousands of deaths each year in the United States. Despite the public health burden, medical and device therapies for HF significantly improve clinical outcomes and, in a subset of patients, can cause reversal of abnormalities in cardiac structure and function, termed "myocardial recovery." By identifying novel patterns in high-dimensional data, artificial intelligence (AI) and machine learning (ML) algorithms can enhance the identification of key predictors and molecular drivers of myocardial recovery. Emerging research in the area has begun to demonstrate exciting results that could advance the standard of care. Although major obstacles remain to translate this technology to clinical practice, AI and ML hold the potential to usher in a new era of purposeful myocardial recovery programs based on precision medicine. In this review, we discuss applications of ML to the prediction of myocardial recovery, potential roles of ML in elucidating the mechanistic basis underlying recovery, barriers to the implementation of ML in clinical practice, and areas for future research.

Learnings from the 2024 Utah Cardiac Recovery Symposium: A Roadmap for the Field of Myocardial Recovery

The 12th annual Utah Cardiac Recovery Symposium (U-CARS) in 2024 continued its mission to advance cardiac recovery by uniting experts across various fields. The symposium featured key presentations on cutting-edge topics such as CRISPR gene editing for heart failure, guideline-directed medical therapy for heart failure (HF) with improved/recovered ejection fraction (HFimpEF), the role of extracorporeal cardiopulmonary resuscitation (ECPR) in treating cardiac arrest, and others. Discussions explored genetic and metabolic contributions to HF, emphasized the importance of maintaining pharmacotherapy in HFimpEF to prevent relapse, and identified future research directions including refining ECPR protocols, optimizing patient selection, and leveraging genetic insights to enhance therapeutic strategies.

Impact of Diabetes and Glycemia on Cardiac Improvement and Adverse Events Following Mechanical Circulatory Support

BACKGROUND

Type 2 diabetes is prevalent in cardiovascular disease and contributes to excess morbidity and mortality. We sought to investigate the effect of glycemia on functional cardiac improvement, morbidity, and mortality in durable left ventricular assist device (LVAD) recipients.

METHODS AND RESULTS

Consecutive patients with an LVAD were prospectively evaluated (n=531). After excluding patients missing pre-LVAD glycated hemoglobin (HbA1c) measurements or having inadequate post-LVAD follow-up, 375 patients were studied. To assess functional cardiac improvement, we used absolute left ventricular ejection fraction change (ΔLVEF: LVEF post-LVAD-LVEF pre-LVAD). We quantified the association of pre-LVAD HbA1c with ΔLVEF as the primary outcome, and all-cause mortality and LVAD-related adverse event rates (ischemic stroke/transient ischemic attack, intracerebral hemorrhage, gastrointestinal bleeding, LVAD-related infection, device thrombosis) as secondary outcomes. Last, we assessed HbA1c differences pre- and post-LVAD. Patients with type 2 diabetes were older, more likely men suffering ischemic cardiomyopathy, and had longer heart failure duration. Pre-LVAD HbA1c was inversely associated with ΔLVEF in patients with nonischemic cardiomyopathy but not in those with ischemic cardiomyopathy, after adjusting for age, sex, heart failure duration, and left ventricular end-diastolic diameter. Pre-LVAD HbA1c was not associated with all-cause mortality, but higher pre-LVAD HbA1c was shown to increase the risk of intracerebral hemorrhage, LVAD-related infection, and device thrombosis by 3 years on LVAD support (P<0.05 for all). HbA1c decreased from 6.68±1.52% pre-LVAD to 6.11±1.33% post-LVAD (P<0.001).

CONCLUSIONS

Type 2 diabetes and pre-LVAD glycemia modify the potential for functional cardiac improvement and the risk for adverse events on LVAD support. The degree and duration of pre-LVAD glycemic control optimization to favorably affect these outcomes warrants further investigation.

Mechanisms of myocardial reverse remodelling and its clinical significance: A scientific statement of the ESC Working Group on Myocardial Function

Cardiovascular disease (CVD) is the leading cause of morbimortality in Europe and worldwide. CVD imposes a heterogeneous spectrum of cardiac remodelling, depending on the insult nature, that is, pressure or volume overload, ischaemia, arrhythmias, infection, pathogenic gene variant, or cardiotoxicity. Moreover, the progression of CVD-induced remodelling is influenced by sex, age, genetic background and comorbidities, impacting patients' outcomes and prognosis. Cardiac reverse remodelling (RR) is defined as any normative improvement in cardiac geometry and function, driven by therapeutic interventions and rarely occurring spontaneously. While RR is the outcome desired for most CVD treatments, they often only slow/halt its progression or modify risk factors, calling for novel and more timely RR approaches. Interventions triggering RR depend on the myocardial insult and include drugs (renin-angiotensin-aldosterone system inhibitors, beta-blockers, diuretics and sodium-glucose cotransporter 2 inhibitors), devices (cardiac resynchronization therapy, ventricular assist devices), surgeries (valve replacement, coronary artery bypass graft), or physiological responses (deconditioning, postpartum). Subsequently, cardiac RR is inferred from the degree of normalization of left ventricular mass, ejection fraction and end-diastolic/end-systolic volumes, whose extent often correlates with patients' prognosis. However, strategies aimed at achieving sustained cardiac improvement, predictive models assessing the extent of RR, or even clinical endpoints that allow for distinguishing complete from incomplete RR or adverse remodelling objectively, remain limited and controversial. This scientific statement aims to define RR, clarify its underlying (patho)physiologic mechanisms and address (non)pharmacological options and promising strategies to promote RR, focusing on the left heart. We highlight the predictors of the extent of RR and review the prognostic significance/impact of incomplete RR/adverse remodelling. Lastly, we present an overview of RR animal models and potential future strategies under pre-clinical evaluation.

A self-reinforcing cycle hypothesis in heart failure pathogenesis

Heart failure is a progressive syndrome with high morbidity and mortality rates. Here, we suggest that chronic exposure of the heart to risk factors for heart failure damages heart mitochondria, thereby impairing energy production to levels that can suppress the heart's ability to pump blood and repair mitochondria (both energy-consuming processes). As damaged mitochondria accumulate, the heart becomes deprived of energy in a 'self-reinforcing cycle', which can persist after the heart is no longer chronically exposed to (or after antagonism of) the risk factors that initiated the cycle. Together with other previously described pathological mechanisms, this proposed cycle can help explain (1) why heart failure progresses, (2) why it can recur after cessation of treatment, and (3) why heart failure is often accompanied by dysfunction of multiple organs. Ideally, therapy of heart failure syndrome would be best attempted before the self-reinforcing cycle is triggered or designed to break the self-reinforcing cycle.

Challenging and target-based shifting strategies for heart failure treatment: An update from the last decades

Heart failure (HF) is a major global health problem afflicting millions worldwide. Despite the significant advances in therapies and prevention, HF still carries very high morbidity and mortality, requiring enormous healthcare-related expenditure, and the search for new weapons goes on. Following initial treatment strategies targeting inotropism and congestion, attention has focused on offsetting the neurohormonal overactivation and three main therapies, including angiotensin-converting enzyme inhibitors or angiotensin II type 1 receptor antagonists, β-adrenoceptor antagonists, and mineralocorticoid receptor antagonists, have been the foundation of standard treatment for patients with HF. Recently, a paradigm shift, including angiotensin receptor-neprilysin inhibitor, sodium glucose co-transporter 2 inhibitor, and ivabradine, has been added. Moreover, soluble guanylate cyclase stimulator, elamipretide, and omecamtiv mecarbil have come out as a next-generation therapeutic agent for patients with HF. Although these pharmacologic therapies have been significantly successful in relieving symptoms, there is still no complete cure for HF. We may be currently entering a new era of treatment for HF with animal experiments and human clinical trials assessing the value of antibody-based immunotherapy and gene therapy as a novel therapeutic strategy. Such tempting therapies still have some challenges to be addressed but may become a weighty option for treatment of HF. This review article will compile the paradigm shifts in HF treatment over the past dozen years or so and illustrate current landscape of antibody-based immunotherapy and gene therapy as a new therapeutic algorithm for patients with HF.

Heart Failure With Improved Ejection Fraction: Prevalence, Predictors, and Guideline-Directed Medical Therapy

Recently, a new category of heart failure with improved ejection fraction (HFimpEF) has emerged in the classification system. This is defined as the subgroup of patients with heart failure with reduced ejection fraction (HFrEF) whose left ventricular ejection fraction has recovered partially or completely, with no specific cut-off values established yet in the guidelines. In our review, we aim to provide an overview of prevalence, predictors, mechanism of remodeling, and management strategies regarding HFimpEF. These patients constitute a sizeable cohort among patients with reduced ejection fraction. Certain patient characteristics including younger age and female gender, absence of comorbid conditions, low levels of biomarkers, and non-ischemic etiology were identified as positive predictors. The heart undergoes significant maladaptive changes post failure leading to adverse remodeling influenced etiology and duration. Goal-directed medical therapy including beta-blockers, angiotensin-converting enzyme inhibitors (ACEIs), and angiotensin II receptor blockers (ARBs) have notably improved cardiac function by inducing reverse remodeling. Despite a more favorable prognosis compared to HFrEF, patients with improved ejection fraction (EF) still face clinical events and reduced quality of life, and remain at risk of adverse outcomes. Although the evidence is scarce, it is advisable to continue treatment modalities despite improvement in EF, including device therapies, to prevent relapse and clinical deterioration. It is imperative to conduct further research to understand the mechanism leading to EF amelioration and establish guidelines to identify and direct management strategies.

Profiling the Biomechanical Responses to Workload on the Human Myocyte to Explore the Concept of Myocardial Fatigue and Reversibility: Rationale and Design of the POWER Heart Failure Study

It remains unclear why some patients develop heart failure without evidence of structural damage. One theory relates to impaired myocardial energetics and ventricular-arterial decoupling as the heart works against adverse mechanical load. In this original study, we propose the novel concept of myocardial fatigue to capture this phenomenon and aim to investigate this using human cardiomyocytes subjected to a modern work-loop contractility model that closely mimics in vivo cardiac cycles. This proof-of-concept study (NCT04899635) will use human myocardial tissue samples from patients undergoing cardiac surgery to develop a reproducible protocol to isolate robust calcium-tolerant cardiomyocytes. Thereafter, work-loop contractility experiments will be performed over a range of preload, afterload and cycle frequency as a function of time to elicit any reversible reduction in contractile performance (i.e. fatigue). This will provide novel insight into mechanisms behind heart failure and myocardial recovery and serve as a valuable research platform in translational cardiovascular research.

Trajectory change of left ventricular ejection fraction after rhythm control for atrial fibrillation in heart failure

AIMS

Rhythm control therapy has shown great benefits for patients with atrial fibrillation (AF) and heart failure (HF). However, few studies have evaluated the effects of rhythm control on left ventricular ejection fraction (LVEF) trajectory across the whole HF spectrum. Our study explored the prevalence and predictors of LVEF trajectory changes and their prognostic implications following rhythm control.

METHODS AND RESULTS

Depending on the treatment strategy, the cohort was classified into rhythm and rate control groups. Alterations in HF types and LVEF trajectory were recorded. The observational endpoints were all-cause mortality and HF-related admission. Predictors of LVEF trajectory improvement in the rhythm control group were evaluated. After matching, the two groups had similar age [mean age (years): rhythm/rate control: 63.96/65.13] and gender [male: rhythm/rate control: n = 228 (55.6%)/233 (56.8%)]. Based on baseline LVEF measurement, the post-matched cohort had 490 HF with preserved ejection fraction (rhythm/rate control: n = 260/230; median LVEF: 58.00%/57.00%), 99 HF with mildly reduced ejection fraction (rhythm/rate control: n = 50/49; median LVEF: 45.00%/46.00%), and 231 HF with reduced ejection fraction (rhythm/rate control: n = 100/131; median LVEF: 32.50%/33.00%). Trajectory analysis found that the rhythm control group had a greater percentage of LVEF trajectory improvement than the rate control group [80 (53.3%) vs. 71 (39.4%), P = 0.012]. Cox regression analysis also showed that the rhythm control group was more likely to have improved LVEF trajectory compared with the rate control group {hazard ratio [HR] 1.671 [95% confidence interval (CI) 1.196-2.335], P = 0.003}. In the survival analysis, the rhythm control group experienced significant lower risks of all-cause mortality [HR 0.600 (95% CI 0.366-0.983), P = 0.043] and HF-related admission [HR 0.611 (95% CI 0.496-0.753), P < 0.001]. In the rhythm control subgroup, E/e' [odds ratio (OR) 0.878 (95% CI 0.792-0.974), P = 0.014], left ventricular end-diastolic diameter [OR 0.874 (95% CI 0.777-0.983), P = 0.024], and CHA2DS2-VASc score (congestive HF, hypertension, age ≥75 years, diabetes mellitus, stroke or transient ischaemic attack, vascular disease, age 65-74 years, and sex category) [OR 0.647 (95% CI 0.438-0.955), P = 0.028] were identified as three independent predictors of LVEF trajectory improvement.

CONCLUSIONS

Rhythm control is associated with improved LVEF trajectory and clinical outcomes and may thus be considered the optimal therapeutic strategy for patients with both HF and AF.

Reduced DNMT1 levels induce cell apoptosis via upregulation of METTL3 in cardiac hypertrophy

DNA methylation is also involved in the development and progression of cardiac diseases. Although studies have shown that DNA methylation and RNA m6A methylation play an important role in the development of myocardial hypertrophy, whether DNA methylation and RNA m6A methylation have a coordinated role in the development of myocardial hypertrophy and influence each other is still unknown. Here, we found that DNMT1 expression was downregulated in TAC mice and Ang II-treated NRCMs. Moreover, DNMT1 overexpression inhibited Ang II-induced apoptosis of NRCMs. Furthermore, we found that the expression of METTL3 was up-regulated after inhibiting the expression of DNMT1 by a DNMT1 inhibitor or small interfering RNA. In addition, ectopic expression DNMT1 inhibited METTL3 expression in NRCMs. Furthermore, METTL3 expression was elevated in NRCMs treated with Ang II, and suppression of METTL3 inhibited cell apoptosis induced by Ang II in NRCMs.In addition, this study revealed that the DNMT1/METTL3 pathway affected Ang II-induced apoptosis in NRCMs. Finally, this study found that DNMT1, but not METTL3, might directly regulated the ANP and BNP expression. Collectively, our findings revealed the role of the DNMT1/METTL3 pathway in cardiac hypertrophy and provided a novel molecular mechanism describing the physiological and pathological processes.

The value of using left ventricular pressure-strain loops to evaluate myocardial work in predicting heart failure with improved ejection fraction

BACKGROUND

The ultrasound left ventricular pressure-strain loop (LV PSL) was applied to evaluate myocardial work in heart failure with improved ejection fraction (HFimpEF) versus patients with persistent heart failure with reduced ejection fraction (HFrEF) to investigate the value of myocardial work parameters in predicting HFimpEF.

METHODS

We collected 120 patients with HFrEF and recorded clinical characteristics and echocardiographic parameters (PSL technique) of patients. Patients were divided into HFimpEF group or persistent HFrEF group according to the outcome of follow-up. Furthermore, differential clinical and echocardiographic parameters were determined by Student's t-test. We recognized the important echocardiographic parameters to predict whether patients would recover to HFimpEF using the univariate logistic regression analysis and ROC curves. In addition, the multivariate logistic regression models were constructed and evaluated using Delong test and decision curve analysis.

RESULTS

Firstly, the HFimpEF group had a higher prevalence of hypertension and higher systolic blood pressure (P-values <0.05). In terms of echocardiographic parameters, HFimpEF group also had higher LVEF, LV GLS, GCW, GWE, and GWI and lower LVEDD (P-values <0.01). In particular, LVEF, LVEDD, GLS, GWI, and GCW were robust predictors of the conversion of HFrEF patients to HFimpEF (AUC >0.70, P-values <0.05). Finally, we determined that the predictive Model 4 (LVEF, LVEDD, GLS, and GCW) had the optimal diagnostic power.

CONCLUSION

The model constructed by GCW with LVEF, LVEDD, and GLS has important predictive value for HFimpEF, which is an effective clinical decision-making tool for providing disease assessment.

Cardiac magnetic resonance for the early prediction of reverse left ventricular remodeling in patients with ST-segment elevation myocardial infarction

OBJECTIVES

To evaluate the changes in cardiac magnetic resonance (CMR) characteristics and investigate the predictors of reverse left ventricular remodeling (r-LVR) in ST-segment elevation myocardial infarction (STEMI) patients.

MATERIALS AND METHODS

Eighty-six STEMI patients (median 56 years) were retrospectively studied. The patients were divided into r-LVR and without r-LVR groups. CMR analysis included LV volume, infarct characteristics, and global and regional myocardial function. The strain and displacement were assessed by CMR-feature tracking. The predictors of r-LVR were analyzed by the logistic regression method.

RESULTS

There were 37 patients in the r-LVR group and 49 patients in the without r-LVR group. At initial CMR, there was no difference in LV volume and global cardiac function between the two groups. However, the infarct zone radial and longitudinal displacements were higher in the r-LVR group (p < 0.05, respectively). At the second CMR, the r-LVR group showed higher LVEF, lower LV volume, and total enhanced mass (all p < 0.05). The infarct zone radial and circumferential strains and radial displacement were higher in the r-LVR group (all p < 0.05). The r-LVR group had better recovery of myocardial injury and function. Of note, microvascular obstruction (MVO) mass (odds ratio: 0.779 (0.613-0.989), p = 0.041) and infarct zone peak longitudinal displacement (PLD) (odds ratio: 1.448 (1.044-2.008), p = 0.026) were independent predictors of r-LVR.

CONCLUSIONS

At initial CMR, there were no differences in global cardiac function between the two groups, but infarct zone displacements were higher in the r-LVR group. The r-LVR group had better recovery of cardiac function. In addition, MVO mass and infarct zone PLD were independent predictors of r-LVR.

CLINICAL RELEVANCE STATEMENT

Our study assessed changes in cardiac structure, function, and tissue characteristics after STEMI by CMR, investigated the best predictors of r-LVR in STEMI patients, and laid the foundation for the development of new parameter-guided treatment strategies for STEMI patients.

KEY POINTS

• At initial CMR, the reverse left ventricular remodeling (r-LVR) group had less myocardial damage and higher infarct zone displacement, but there were no differences in global function between the two groups. • Both groups showed recovery of myocardial injury and cardiac function over time, but the r-LVR group had less enhanced mass and better cardiac function compared to the without r-LVR group at the second CMR. • Microvascular obstruction mass and infarct zone peak longitudinal displacement by cardiac magnetic resonance feature-tracking were significant predictors of r-LVR in STEMI patients.

Heart Failure With Recovered Ejection Fraction in Patients With Nonischemic Cardiomyopathy: Characteristics, Outcomes, and Long-term Follow-up

BACKGROUND

Duration of recovery and long-term outcomes have not been well-described in a large cohort of patients with heart failure with recovered ejection fraction (HFrecEF) owing to nonischemic cardiomyopathy. The aim of the study was to characterize the duration of recovery and long-term outcomes of patients with HFrecEF.

METHODS AND RESULTS

We performed a retrospective analysis of our institution's databases. Only patients with nonischemic cardiomyopathy, a chronic HF diagnosis, and a previous left ventricular ejection fraction (LVEF) of ≤35% who had a subsequent LVEF of ≥50% were considered to have recovery. Patients with an LVEF of ≤35% who did not recover served as the comparison group. Included were 2319 patients with an LVEF of ≤35%, of whom 465 (20% [18.4%-21.7%]) met the above criteria for recovery (HFrecEF group). Recovery in the HFrecEF group was temporary in most cases, with 50% of patients experiencing a decline in LVEF to <50% within 3.5 [interquartile range 2.4-4.9] years after the day of recovery. Age and sex adjusted death and hospitalization were lower in the HFrecEF group than the HFrEF group (HR 0.29 [interquartile range 0.20-0.41] for death and 0.44 [interquartile range 0.32-0.60] for HF hospitalization, P < .0001 for both). Longer recovery was associated with better survival, with patients spending >5 years in recovery (LVEF of ≥50%) displaying the highest survival rates (83% alive at 10 years after recovery). Survival after recurrence of LV dysfunction was longer for those whose recovery duration was >1 year.

CONCLUSIONS

Patients with nonischemic HFrecEF display a unique clinical course. Although recovery is temporary in most cases, patients with HFrecEF display lower mortality and hospitalization rates, with the more durable the recovery of LV systolic function, the longer survival can be anticipated.

Cardiac reverse remodelling by imaging parameters with recent changes to guideline medical therapy in heart failure

Recently established heart failure therapies, including sodium glucose co-transporter 2 inhibitors, angiotensin-neprilysin inhibitors, and cardiac resynchronization therapy, have led to both clinical and structural improvements. Reverse remodelling describes the structural and functional responses to therapy and has been shown to correlate with patients' clinical response, acting as a biomarker for treatment success. The introduction of these new therapeutic agents in addition to advances in non-invasive cardiac imaging has led to an expansion in the evaluation and the validation of cardiac reverse remodelling. Methods including volumetric changes as well as strain and myocardial work have all been shown to be non-invasive end-points of reverse remodelling, correlating with clinical outcomes. Our review summarizes the current available evidence on reverse remodelling in heart failure by the non-invasive cardiac imaging techniques, in particular transthoracic echocardiography.

Acute heart failure: mechanisms and pre-clinical models-a Scientific Statement of the ESC Working Group on Myocardial Function

While chronic heart failure (CHF) treatment has considerably improved patient prognosis and survival, the therapeutic management of acute heart failure (AHF) has remained virtually unchanged in the last decades. This is partly due to the scarcity of pre-clinical models for the pathophysiological assessment and, consequently, the limited knowledge of molecular mechanisms involved in the different AHF phenotypes. This scientific statement outlines the different trajectories from acute to CHF originating from the interaction between aetiology, genetic and environmental factors, and comorbidities. Furthermore, we discuss the potential molecular targets capable of unveiling new therapeutic perspectives to improve the outcome of the acute phase and counteracting the evolution towards CHF.

Factors Associated With Maintenance of an Improved Ejection Fraction: An Echocardiogram-Based Registry Study

Background Heart failure with improved ejection fraction (EF) is increasingly recognized as a sizable and distinct entity. While the features associated with improvedEF have been explored and new guidelines have emerged, factors associated with sustaining an improved EF over time have not been defined. We aimed to assess factors associated with maintenance of an improved EF in a large real-world patient cohort. Methods and Results A total of 7070 participants with heart failure with improved EF and a subsequent echocardiogram performed after at least 9 months of follow-up were included in a retrospective cohort study conducted at the Cleveland Clinic in Cleveland, Ohio. Multiple logistic regression models, adjusted for demographics, comorbidities, and medications were built to identify characteristics and therapeutic interventions associated with maintaining an improved EF. Mean age (SD) was 64.9 (13.8) years, 62.7% were men, and 75.1% were White participants. White race and the use of angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, or angiotensin receptor-neprilysin inhibitors were associated with maintaining the EF at least 9 months after EF improvement. In contrast, male sex or having atrial fibrillation/flutter, coronary artery disease, history of myocardial infarction, presence of an implanted cardioverter-defibrillator, and use of loop diuretics were associated with a decline in EF after previously documented improvement. Conclusions Continued use of renin-angiotensin-aldosterone system inhibitors was associated with maintaining the EF beyond the initial improvement phase.

Benchtop Models of Patient-Specific Intraventricular Flow During Heart Failure and LVAD Support

The characterization of intraventricular flow is critical to evaluate the efficiency of fluid transport and potential thromboembolic risk but challenging to measure directly in advanced heart failure (HF) patients with left ventricular assist device (LVAD) support. The study aims to validate an in-house mock loop (ML) by simulating specific conditions of HF patients with normal and prosthetic mitral valves (MV) and LVAD patients with small and dilated left ventricle volumes, then comparing the flow-related indices result of vortex parameters, residence time (RT), and shear-activation potential (SAP). Patient-specific inputs for the ML studies included heart rate, end-diastolic and end-systolic volumes, ejection fraction, aortic pressure, E/A ratio, and LVAD speed. The ML effectively replicated vortex development and circulation patterns, as well as RT, particularly for HF patient cases. The LVAD velocity fields reflected altered flow paths, in which all or most incoming blood formed a dominant stream directing flow straight from the mitral valve to the apex. RT estimation of patient and ML compared well for all conditions, but SAP was substantially higher in the LVAD cases of the ML. The benchtop system generated comparable and reproducible hemodynamics and fluid dynamics for patient-specific conditions, validating its reliability and clinical relevance. This study demonstrated that ML is a suitable platform to investigate the fluid dynamics of HF and LVAD patients and can be utilized to investigate heart-implant interactions.

Decoding molecular signature on heart of septic mice with distinct left ventricular ejection fraction

Dysregulated cardiac function after sepsis in intensive care unit is known to predict poor long-term outcome and increase mortality. Their pathological feature and molecular mechanism remain unclear. We observed that septic patients with depressed left ventricular ejection fraction (LVEF) have the highest in-hospital and 28 days mortality comparing to patients with hyperdynamic LVEF or with heart failure with preserved LVEF. Echocardiograms reveal that survivors post cecum ligation and puncture (CLP) on rodents have stable LVEF and non-survivors have fluctuated LVEF at CLP early phase. CLP-induced mice fall into three groups based on LVEF 24 h post-surgery: high-, low-, and normal-LVEF. Transcriptomic and proteomic analyses identify jointly and distinctively changed genes, proteins and biologically essential pathways in left ventricles from three CLP groups. Notably, transmission electron microscopy shows different mitochondrial and sarcomere defects associated with LVEF variances. Together, this study systematically characterizes the molecular, morphological, and functional alterations in CLP-induced cardiac injury.

Cardiological Challenges Related to Long-Term Mechanical Circulatory Support for Advanced Heart Failure in Patients with Chronic Non-Ischemic Cardiomyopathy

Long-term mechanical circulatory support by a left ventricular assist device (LVAD), with or without an additional temporary or long-term right ventricular (RV) support, is a life-saving therapy for advanced heart failure (HF) refractory to pharmacological treatment, as well as for both device and surgical optimization therapies. In patients with chronic non-ischemic cardiomyopathy (NICM), timely prediction of HF's transition into its end stage, necessitating life-saving heart transplantation or long-term VAD support (as a bridge-to-transplantation or destination therapy), remains particularly challenging, given the wide range of possible etiologies, pathophysiological features, and clinical presentations of NICM. Decision-making between the necessity of an LVAD or a biventricular assist device (BVAD) is crucial because both unnecessary use of a BVAD and irreversible right ventricular (RV) failure after LVAD implantation can seriously impair patient outcomes. The pre-operative or, at the latest, intraoperative prediction of RV function after LVAD implantation is reliably possible, but necessitates integrative evaluations of many different echocardiographic, hemodynamic, clinical, and laboratory parameters. VADs create favorable conditions for the reversal of structural and functional cardiac alterations not only in acute forms of HF, but also in chronic HF. Although full cardiac recovery is rather unusual in VAD recipients with pre-implant chronic HF, the search for myocardial reverse remodelling and functional improvement is worthwhile because, for sufficiently recovered patients, weaning from VADs has proved to be feasible and capable of providing survival benefits and better quality of life even if recovery remains incomplete. This review article aimed to provide an updated theoretical and practical background for those engaged in this highly demanding and still current topic due to the continuous technical progress in the optimization of long-term VADs, as well as due to the new challenges which have emerged in conjunction with the proof of a possible myocardial recovery during long-term ventricular support up to levels which allow successful device explantation.

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.

The complete reversal effect following angiotensin-converting enzyme inhibitors or angiotensin receptor blockers and beta-blockers after the primary diagnosis of dilated cardiomyopathy

Background

Whether combination administration of angiotensin-converting enzyme inhibitors (ACEIs), angiotensin receptor blockers (ARBs), and beta-blockers (BBs) has a "reversal" effect on cardiac structure and function for first-diagnosed idiopathic dilated cardiomyopathy (FSIDCM) patients with unclear etiologies and inducements is unknown.

Materials and Methods

We studied the effect of the protocol on FSIDCM patients. The effect was investigated in 26 FSIDCM patients. The criteria of "complete reversal" included left ventricular end-diastolic diameter (LVEDD) ≤50 mm for females or ≤55 mm for males and left ventricular ejection fraction (LVEF) ≥45%; the criteria of "partial reversal" was the decreased rate of LVEDD (ΔLVEDD) >10% or the increase rate of LVEF (ΔLVEF) >10%; the criteria of "no reversal" included LVEDD >50 mm for females or >55 mm for males and ΔLVEDD <10%, and LVEF <45% and ΔLVEF <10%.

Results

Within the follow-up period, nine patients showed "complete reversal," eight "partial reversal," and nine "no reversal." Improvements in echocardiogram parameters were the most significant in "complete reversal" patients (P < 0.001), followed by "partial reversal" and "no reversal" patients (P < 0.05). The QRS (Q wave, R wave, S wave) duration and symptoms duration in "complete reversal" patients were the shortest, followed by "partial reversal" and "no reversal" patients.

Conclusion

ACEIs or ARBs and BBs have a "complete reversal" effect on the left ventricular size and function of some FSIDCM patients. Patients with a narrow QRS and short symptom duration may have a good response.

Treatment Strategies for Cardiomyopathy in Children: A Scientific Statement From the American Heart Association

This scientific statement from the American Heart Association focuses on treatment strategies and modalities for cardiomyopathy (heart muscle disease) in children and serves as a companion scientific statement for the recent statement on the classification and diagnosis of cardiomyopathy in children. We propose that the foundation of treatment of pediatric cardiomyopathies is based on these principles applied as personalized therapy for children with cardiomyopathy: (1) identification of the specific cardiac pathophysiology; (2) determination of the root cause of the cardiomyopathy so that, if applicable, cause-specific treatment can occur (precision medicine); and (3) application of therapies based on the associated clinical milieu of the patient. These clinical milieus include patients at risk for developing cardiomyopathy (cardiomyopathy phenotype negative), asymptomatic patients with cardiomyopathy (phenotype positive), patients with symptomatic cardiomyopathy, and patients with end-stage cardiomyopathy. This scientific statement focuses primarily on the most frequent phenotypes, dilated and hypertrophic, that occur in children. Other less frequent cardiomyopathies, including left ventricular noncompaction, restrictive cardiomyopathy, and arrhythmogenic cardiomyopathy, are discussed in less detail. Suggestions are based on previous clinical and investigational experience, extrapolating therapies for cardiomyopathies in adults to children and noting the problems and challenges that have arisen in this experience. These likely underscore the increasingly apparent differences in pathogenesis and even pathophysiology in childhood cardiomyopathies compared with adult disease. These differences will likely affect the utility of some adult therapy strategies. Therefore, special emphasis has been placed on cause-specific therapies in children for prevention and attenuation of their cardiomyopathy in addition to symptomatic treatments. Current investigational strategies and treatments not in wide clinical practice, including future direction for investigational management strategies, trial designs, and collaborative networks, are also discussed because they have the potential to further refine and improve the health and outcomes of children with cardiomyopathy in the future.

Myocardial recovery following left ventricular assist device implantation

Durable left ventricular assist devices (LVADs) have consistently shown improved mortality and morbidity in patients with end-stage heart failure. Select patients with LVADs may experience significant enough myocardial recovery after device implantation to allow for explantation or decommissioning. While earlier trials suggested a high incidence of recovery, real-world clinical data have demonstrated this to be a much rarer phenomenon. Whether or not patients experience recovery, practices such as speed optimization and usage of guideline-directed medical therapy can improve patient outcomes.

Myocardial Recovery

In this paper, the feasibility of myocardial recovery is analyzed through a literature review. First, the phenomena of remodeling and reverse remodeling are analyzed, approached through the physics of elastic bodies, and the terms myocardial depression and myocardial recovery are defined. Continuing, potential biochemical, molecular, and imaging markers of myocardial recovery are reviewed. Then, the work focuses on therapeutic techniques that can facilitate the reverse remodeling of the myocardium. Left ventricular assist device (LVAD) systems are one of the main ways to promote cardiac recovery. The changes that take place in cardiac hypertrophy, extracellular matrix, cell populations and their structural elements, β-receptors, energetics, and several biological processes, are reviewed. The attempt to wean the patients who experienced cardiac recovery from cardiac assist device systems is also discussed. The characteristics of the patients who will benefit from LVAD are presented and the heterogeneity of the studies performed in terms of patient populations included, diagnostic tests performed, and their results are addressed. The experience with cardiac resynchronization therapy (CRT) as another way to promote reverse remodeling is also reviewed. Myocardial recovery is a phenomenon that presents with a continuous spectrum of phenotypes. There is a need for algorithms to screen suitable patients who may benefit and identify specific ways to enhance this phenomenon in order to help combat the heart failure epidemic.

A review on experimental surgical models and anesthetic protocols of heart failure in rats

Heart failure (HF) is a serious health and economic burden worldwide, and its prevalence is continuously increasing. Current medications effectively moderate the progression of symptoms, and there is a need for novel preventative and reparative treatments. The development of novel HF treatments requires the testing of potential therapeutic procedures in appropriate animal models of HF. During the past decades, murine models have been extensively used in fundamental and translational research studies to better understand the pathophysiological mechanisms of HF and develop more effective methods to prevent and control congestive HF. Proper surgical approaches and anesthetic protocols are the first steps in creating these models, and each successful approach requires a proper anesthetic protocol that maintains good recovery and high survival rates after surgery. However, each protocol may have shortcomings that limit the study's outcomes. In addition, the ethical regulations of animal welfare in certain countries prohibit the use of specific anesthetic agents, which are widely used to establish animal models. This review summarizes the most common and recent surgical models of HF and the anesthetic protocols used in rat models. We will highlight the surgical approach of each model, the use of anesthesia, and the limitations of the model in the study of the pathophysiology and therapeutic basis of common cardiovascular diseases.

Prognosis after discontinuing renin angiotensin aldosterone system inhibitor for heart failure with restored ejection fraction after acute myocardial infarction

Prognostic effect of discontinuing renin-angiotensin-aldosterone-system-inhibitor (RAASi) for patients with heart failure (HF) after acute myocardial infarction (AMI) whose left ventricular (LV) systolic function was restored during follow-up is unknown. To investigate the outcome after discontinuing RAASi in post-AMI HF patients with restored LV ejection fraction (EF). Of 13,104 consecutive patients from the nationwide, multicenter, and prospective Korea Acute Myocardial Infarction-National Institutes of Health (KAMIR-NIH) registry, HF patients with baseline LVEF < 50% that was restored to ≥ 50% at 12-month follow-up were selected. Primary outcome was a composite of all-cause death, spontaneous MI, or rehospitalization for HF at 36-month after index procedure. Of 726 post-AMI HF patients with restored LVEF, 544 maintained RAASi (Maintain-RAASi) beyond 12-month, 108 stopped RAASi (Stop-RAASi), and 74 did not use RAASi (RAASi-Not-Used) at baseline and follow-up. Systemic hemodynamics and cardiac workloads were similar among groups at baseline and during follow-up. Stop-RAASi group showed elevated NT-proBNP than Maintain-RAASi group at 36-month. Stop-RAASi group showed significantly higher risk of primary outcome than Maintain-RAASi group (11.4% vs. 5.4%; adjusted hazard ratio [HR_adjust] 2.20, 95% confidence interval [CI] 1.09-4.46, P = 0.028), mainly driven by increased risk of all-cause death. The rate of primary outcome was similar between Stop-RAASi and RAASi-Not-Used group (11.4% vs. 12.1%; HR_adjust 1.18 [0.47-2.99], P = 0.725). In post-AMI HF patients with restored LV systolic function, RAASi discontinuation was associated with significantly increased risk of all-cause death, MI, or rehospitalization for HF. Maintaining RAASi will be necessary for post-AMI HF patients, even after LVEF is restored.

Effect of mechanical unloading on genome-wide DNA methylation profile of the failing human heart

Heart failure (HF) is characterized by global alterations in myocardial DNA methylation, yet little is known about the epigenetic regulation of the noncoding genome and potential reversibility of DNA methylation with left ventricular assist device (LVAD) therapy. Genome-wide mapping of myocardial DNA methylation in 36 patients with HF at LVAD implantation, 8 patients at LVAD explantation, and 7 nonfailing (NF) donors using a high-density bead array platform identified 2,079 differentially methylated positions (DMPs) in ischemic cardiomyopathy (ICM) and 261 DMPs in nonischemic cardiomyopathy (NICM). LVAD support resulted in normalization of 3.2% of HF-associated DMPs. Methylation-expression correlation analysis yielded several protein-coding genes that are hypomethylated and upregulated (HTRA1, FBXO16, EFCAB13, and AKAP13) or hypermethylated and downregulated (TBX3) in HF. A potentially novel cardiac-specific super-enhancer long noncoding RNA (lncRNA) (LINC00881) is hypermethylated and downregulated in human HF. LINC00881 is an upstream regulator of sarcomere and calcium channel gene expression including MYH6, CACNA1C, and RYR2. LINC00881 knockdown reduces peak calcium amplitude in the beating human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). These data suggest that HF-associated changes in myocardial DNA methylation within coding and noncoding genomes are minimally reversible with mechanical unloading. Epigenetic reprogramming strategies may be necessary to achieve sustained clinical recovery from heart failure.

Heart failure with recovered ejection fraction: Current understanding and future prospects

Heart failure with reduced ejection fraction (HFrEF) is a prevalent kind of heart failure in which a significant amount of the ejection fraction can be repaired, and left ventricular remodeling and dysfunction can be reversed or even restored completely. However, a considerable number of patients still present clinical signs and biochemical features of incomplete recovery from the pathophysiology of heart failure and are at risk for adverse outcomes such as re-deterioration of systolic function and recurrence of HFrEF. Furthermore, it is revealed from a microscopic perspective that even if partial or complete reverse remodeling occurs, the morphological changes of cardiomyocytes, extracellular matrix deposition, and abnormal transcription and expression of pathological genes still exist. Patients with "recovered ejection fraction" have milder clinical symptoms and better outcomes than those with continued reduction of ejection fraction. Based on the unique characteristics of this subgroup and the existence of many unknowns, the academic community defines it as a new category-heart failure with recovered ejection fraction (HFrecEF). Because there is a shortage of natural history data for this population as well as high-quality clinical and basic research data, it is difficult to accurately evaluate clinical risk and manage this population. This review will present the current understanding of HFrecEF from the limited literature.

Temporal Changes in Extracellular Vesicle Hemostatic Protein Composition Predict Favourable Left Ventricular Remodeling after Acute Myocardial Infarction

The subset of plasma extracellular vesicles (EVs) that coprecipitate with low-density lipoprotein (LDL-EVs) carry coagulation and fibrinolysis pathway proteins as cargo. We investigated the association between LDL-EV hemostatic/fibrinolysis protein ratios and post-acute myocardial infarction (post-AMI) left ventricular (LV) remodeling which precedes heart failure. Protein concentrations of von Willebrand factor (VWF), SerpinC1 and plasminogen were determined in LDL-EVs extracted from plasma samples obtained at baseline (within 72 h post-AMI), 1 month and 6 months post-AMI from 198 patients. Patients were categorized as exhibiting adverse (n = 98) or reverse (n = 100) LV remodeling based on changes in LV end-systolic volume (increased or decreased ≥15) over a 6-month period. Multiple level longitudinal data analysis with structural equation (ML-SEM) model was used to assess predictive value for LV remodeling independent of baseline differences. At baseline, protein levels of VWF, SerpinC1 and plasminogen in LDL-EVs did not differ between patients with adverse versus reverse LV remodeling. At 1 month post-AMI, protein levels of VWF and SerpinC1 decreased whilst plasminogen increased in patients with adverse LV remodeling. In contrast, VWF and plasminogen decreased whilst SerpinC1 remained unchanged in patients with reverse LV remodeling. Overall, compared with patients with adverse LV remodeling, higher levels of SerpinC1 and VWF but lower levels of plasminogen resulted in higher ratios of VWF:Plasminogen and SerpinC1:Plasminogen at both 1 month and 6 months post-AMI in patients with reverse LV remodeling. More importantly, ratios VWF:Plasminogen (AUC = 0.674) and SerpinC1:Plasminogen (AUC = 0.712) displayed markedly better prognostic power than NT-proBNP (AUC = 0.384), troponin-I (AUC = 0.467) or troponin-T (AUC = 0.389) (p < 0.001) to predict reverse LV remodeling post-AMI. Temporal changes in the ratios of coagulation to fibrinolysis pathway proteins in LDL-EVs outperform current standard plasma biomarkers in predicting post-AMI reverse LV remodeling. Our findings may provide clinical cues to uncover the cellular mechanisms underpinning post-AMI reverse LV remodeling.

Prognostic Value of Left Ventricular Global Longitudinal Strain in Patients With Congenital Heart Disease

BACKGROUND

Left ventricular global longitudinal strain (LVGLS) has been shown to improve risk stratification in patients with LV systolic dysfunction and subsequent recovery of LV ejection fraction (LVEF) in the acquired heart disease population. The purpose of this study was to assess the relationship between LVGLS and cardiovascular events (heart failure hospitalization, sustained ventricular tachycardia/appropriate shock, heart transplant, or cardiovascular death) and deterioration in LVEF (absolute decrease in LVEF ≥10% to LVEF <50%) in adults with congenital heart disease.

METHODS

Retrospective cohort study of congenital heart disease patients with previous diagnosis of LV systolic dysfunction (LVEF <50%) and subsequent recovery of LVEF (absolute increase in LVEF of ≥10% to LVEF ≥50%) on subsequent echocardiogram (index echocardiogram). Based on the index echocardiogram, patients were divided into normal LVGLS (absolute LVGLS >18%) versus abnormal LVGLS (absolute LVGLS ≤18%) groups.

RESULTS

Of 193 patients with recovered LVEF, 86 (45%) had normalization of LVGLS at index echocardiogram. A higher absolute LVGLS and use of renin angiotensin aldosterone system antagonist was associated with a lower risk of cardiovascular events and subsequent deterioration in LVEF, while hypertension was associated with higher risk of cardiovascular events and deterioration in LVEF.

CONCLUSIONS

These results suggest that patients with congenital heart disease with recovered LVEF remained at risk for adverse outcomes, and LVGLS can be used to identify patients at risk for adverse outcomes. Medical therapy for heart failure and treatment of hypertension may reduce the risk of adverse outcome, but these findings require empirical validation, hence the need for a clinical trial.

Targeting the Autophagy-Lysosome Pathway in a Pathophysiologically Relevant Murine Model of Reversible Heart Failure

The key biological "drivers" that are responsible for reverse left ventricle (LV) remodeling are not well understood. To gain an understanding of the role of the autophagy-lysosome pathway in reverse LV remodeling, we used a pathophysiologically relevant murine model of reversible heart failure, wherein pressure overload by transaortic constriction superimposed on acute coronary artery (myocardial infarction) ligation leads to a heart failure phenotype that is reversible by hemodynamic unloading. Here we show transaortic constriction + myocardial infarction leads to decreased flux through the autophagy-lysosome pathway with the accumulation of damaged proteins and organelles in cardiac myocytes, whereas hemodynamic unloading is associated with restoration of autophagic flux to normal levels with incomplete removal of damaged proteins and organelles in myocytes and reverse LV remodeling, suggesting that restoration of flux is insufficient to completely restore myocardial proteostasis. Enhancing autophagic flux with adeno-associated virus 9-transcription factor EB resulted in more favorable reverse LV remodeling in mice that had undergone hemodynamic unloading, whereas overexpressing transcription factor EB in mice that have not undergone hemodynamic unloading leads to increased mortality, suggesting that the therapeutic outcomes of enhancing autophagic flux will depend on the conditions in which flux is being studied.

Cardiac fibroblasts and mechanosensation in heart development, health and disease

The term 'mechanosensation' describes the capacity of cells to translate mechanical stimuli into the coordinated regulation of intracellular signals, cellular function, gene expression and epigenetic programming. This capacity is related not only to the sensitivity of the cells to tissue motion, but also to the decryption of tissue geometric arrangement and mechanical properties. The cardiac stroma, composed of fibroblasts, has been historically considered a mechanically passive component of the heart. However, the latest research suggests that the mechanical functions of these cells are an active and necessary component of the developmental biology programme of the heart that is involved in myocardial growth and homeostasis, and a crucial determinant of cardiac repair and disease. In this Review, we discuss the general concept of cell mechanosensation and force generation as potent regulators in heart development and pathology, and describe the integration of mechanical and biohumoral pathways predisposing the heart to fibrosis and failure. Next, we address the use of 3D culture systems to integrate tissue mechanics to mimic cardiac remodelling. Finally, we highlight the potential of mechanotherapeutic strategies, including pharmacological treatment and device-mediated left ventricular unloading, to reverse remodelling in the failing heart.

Clinical implications of left atrial changes after optimization of medical therapy in patients with heart failure

AIMS

Limited data exist regarding the prognostic relevance of changes in left atrial (LA) dimensions in patients with heart failure (HF). We assessed changes in LA dimension and their relation with outcomes after optimization of guideline-directed medical therapy (GDMT) in patients with new-onset or worsening HF.

METHODS AND RESULTS

Left atrial diameter was assessed at baseline and 9 months after GDMT optimization in 632 patients (mean age 65.8 ± 12.1 years, 22.3% female) enrolled in BIOSTAT-CHF. LA adverse remodelling (LAAR) was defined as an increase in LA diameter on transthoracic echocardiography between baseline and 9 months. After the 9-month visit, patients were followed for a median of 13 further months. LAAR was observed in 247 patients (39%). Larger baseline LA diameter (odds ratio [OR] 0.90; 95% confidence interval [CI] 0.87-0.93; p < 0.001) and up-titration to higher doses of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (ACEi/ARBs) (OR 0.56; 95% CI 0.34-0.92; p = 0.022) were independently associated with lower likelihood of LAAR. LAAR was associated with an increased risk of the composite of all-cause mortality or HF hospitalization (log-rank p = 0.007 and adjusted hazard ratio 1.73, 95% CI 1.22-2.45, p = 0.002). The association was more pronounced in patients without a history of atrial fibrillation (p for interaction = 0.009).

CONCLUSION

Among patients enrolled in BIOSTAT-CHF, LAAR was associated with an unfavourable outcome and was prevented by ACEi/ARB up-titration. Changes in LA dimension may be a useful marker of response to treatment and improve risk stratification in patients with HF.

How Do I Optimize Heart Failure Medications for Patients with Hypotension or Chronic Kidney Disease?

HF Medications for Hypotension or CKDThe cornerstone of treatment for HF with reduced ejection fraction is GDMT; however, safely delivering maximal therapy is often hampered by low blood pressure, labile renal function, or both. Reviewing the physiologic basis of GDMT and exploring each drug's mechanism of action and unique properties can enable careful initiation and titration of therapy, even in patients with hypotension or CKD.

Clinical myocardial recovery in advanced heart failure with long term left ventricular assist device support

Left ventricular assist-device (LVAD) implantation is a life-saving therapy for patients with advanced heart failure (HF). With chronic unloading and circulatory support, LVAD-supported hearts often show significant reverse remodeling at the structural, cellular and molecular level. However, translation of these changes into meaningful cardiac recovery allowing LVAD explant is lagging. Part of the reason for this discrepancy is lack of anticipation and hence promotion and evaluation for recovery post LVAD implant. There is additional uncertainty about the long-term course of HF following LVAD explant. In selected patients, however, guided by the etiology of HF, duration of disease and other clinical factors, significant functional improvement and LVAD explantation with long-term freedom from recurrent HF events has been demonstrated to be feasible in a reproducible manner. The identified predictors of myocardial recovery suggest that the elective therapeutic use of potentially less invasive VADs for reversal of HF earlier in the disease process is a future goal that warrants further investigation. Hence, it is prudent to develop and implement tools to predict HF reversibility prior to LVAD implant, optimize unloading-promoted recovery with guideline directed medical therapy and monitor for myocardial improvement. This review article summarizes the clinical aspects of myocardial recovery and together with its companion review article focused on the biological aspects of recovery, they aim to provide a useful framework for clinicians and investigators.