Effect of Sacubitril/Valsartan on Biomarkers of Extracellular Matrix Regulation in Patients With HFpEF

Insights into the post-translational modifications in heart failure

Heart failure (HF), as the terminal manifestation of multiple cardiovascular diseases, causes a huge socioeconomic burden worldwide. Despite the advances in drugs and medical-assisted devices, the prognosis of HF remains poor. HF is well-accepted as a myriad of subcellular dys-synchrony related to detrimental structural and functional remodelling of cardiac components, including cardiomyocytes, fibroblasts, endothelial cells and macrophages. Through the covalent chemical process, post-translational modifications (PTMs) can coordinate protein functions, such as re-localizing cellular proteins, marking proteins for degradation, inducing interactions with other proteins and tuning enzyme activities, to participate in the progress of HF. Phosphorylation, acetylation, and ubiquitination predominate in the currently reported PTMs. In addition, advanced HF is commonly accompanied by metabolic remodelling including enhanced glycolysis. Thus, glycosylation induced by disturbed energy supply is also important. In this review, firstly, we addressed the main types of HF. Then, considering that PTMs are associated with subcellular locations, we summarized the leading regulation mechanisms in organelles of distinctive cell types of different types of HF, respectively. Subsequently, we outlined the aforementioned four PTMs of key proteins and signaling sites in HF. Finally, we discussed the perspectives of PTMs for potential therapeutic targets in HF.

Myocardial fibrosis from the perspective of the extracellular matrix: mechanisms to clinical impact

Fibrosis is defined by the excessive accumulation of extracellular matrix (ECM) and constitutes a central pathophysiological process that underlies tissue dysfunction, across organs, in multiple chronic diseases and during aging. Myocardial fibrosis is a key contributor to dysfunction and failure in numerous diseases of the heart and is a strong predictor of poor clinical outcome and mortality. The excess structural and matricellular ECM proteins deposited by cardiac fibroblasts, is found between cardiomyocytes (interstitial fibrosis), in focal areas where cardiomyocytes have died (replacement fibrosis), and around vessels (perivascular fibrosis). Although myocardial fibrosis has important clinical prognostic value, access to cardiac tissue biopsies for histological evaluation is limited. Despite challenges with sensitivity and specificity, cardiac magnetic resonance imaging (CMR) is the most applicable diagnostic tool in the clinic, and the scientific community is currently actively searching for blood biomarkers reflecting myocardial fibrosis, to complement the imaging techniques. The lack of mechanistic insights into specific pro- and anti-fibrotic molecular pathways has hampered the development of effective treatments to prevent or reverse myocardial fibrosis. Development and implementation of anti-fibrotic therapies is expected to improve patient outcomes and is an urgent medical need. Here, we discuss the importance of the ECM in the heart, the central role of fibrosis in heart disease, and mechanistic pathways likely to impact clinical practice with regards to diagnostics of myocardial fibrosis, risk stratification of patients, and anti-fibrotic therapy.

Obesity: the perfect storm for heart failure

Obesity condition causes morphological and functional alterations involving the cardiovascular system. These can represent the substrates for different cardiovascular diseases, such as atrial fibrillation, coronary artery disease, sudden cardiac death, and heart failure (HF) with both preserved ejection fraction (EF) and reduced EF. Different pathogenetic mechanisms may help to explain the association between obesity and HF including left ventricular remodelling and epicardial fat accumulation, endothelial dysfunction, and coronary microvascular dysfunction. Multi-imaging modalities are required for appropriate recognition of subclinical systolic dysfunction typically associated with obesity, with echocardiography being the most cost-effective technique. Therapeutic approach in patients with obesity and HF is challenging, particularly regarding patients with preserved EF in which few strategies with high level of evidence are available. Weight loss is of extreme importance in patients with obesity and HF, being a primary therapeutic intervention. Sodium-glucose co-transporter-2 inhibitors have been recently introduced as a novel tool in the management of HF patients. The present review aims at analysing the most recent studies supporting pathogenesis, diagnosis, and management in patients with obesity and HF.

Aptamer Proteomics for Biomarker Discovery in Heart Failure With Preserved Ejection Fraction: The PARAGON-HF Proteomic Substudy

BACKGROUND

Prognostic markers and biological pathways linked to detrimental clinical outcomes in heart failure with preserved ejection fraction (HFpEF) remain incompletely defined.

METHODS AND RESULTS

We measured serum levels of 4123 unique proteins in 1117 patients with HFpEF enrolled in the PARAGON-HF (Efficacy and Safety of LCZ696 Compared to Valsartan, on Morbidity and Mortality in Heart Failure Patients With Preserved Ejection Fraction) trial using a modified aptamer proteomic assay. Baseline circulating protein concentrations significantly associated with the primary end point and the timing and occurrence of total heart failure hospitalization and cardiovascular death were identified by recurrent events regression, accounting for multiple testing, adjusted for age, sex, treatment, and anticoagulant use, and compared with published analyses in 2515 patients with heart failure with reduced ejection fraction from the PARADIGM-HF (Prospective Comparison of ARNI With ACEI to Determine Impact on Global Mortality and Morbidity in Heart Failure) and ATMOSPHERE (Efficacy and Safety of Aliskiren and Aliskiren/Enalapril Combination on Morbidity-Mortality in Patients With Chronic Heart Failure) clinical trials. We identified 288 proteins that were robustly associated with the risk of heart failure hospitalization and cardiovascular death in patients with HFpEF. The baseline proteins most strongly related to outcomes included B2M (β-2 microglobulin), TIMP1 (tissue inhibitor of matrix metalloproteinase 1), SERPINA4 (serpin family A member 4), and SVEP1 (sushi, von Willebrand factor type A, EGF, and pentraxin domain containing 1). Overall, the protein-outcome associations in patients with HFpEF did not markedly differ as compared with patients with heart failure with reduced ejection fraction. A proteomic risk score derived in patients with HFpEF was not superior to a previous proteomic score derived in heart failure with reduced ejection fraction nor to clinical risk factors, NT-proBNP (N-terminal pro-B-type natriuretic peptide), or high-sensitivity cardiac troponin.

CONCLUSIONS

Numerous serum proteins linked to metabolic, coagulation, and extracellular matrix regulatory pathways were associated with worse HFpEF prognosis in the PARAGON-HF proteomic substudy. Our results demonstrate substantial similarities among serum proteomic risk markers for heart failure hospitalization and cardiovascular death when comparing clinical trial participants with heart failure across the ejection fraction spectrum.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique Identifiers: NCT01920711, NCT01035255, NCT00853658.

Sacubitril/valsartan and cardiovascular biomarkers among patients with recent COVID-19 infection: The PARACOR-19 randomized clinical trial

AIMS

The PARACOR-19 randomized controlled trial (RCT) was designed to examine the effects of sacubitril/valsartan on markers of cardiac injury, inflammation, structure, and function among patients who have recovered from acute coronavirus disease 2019 (COVID-19) infection.

METHODS AND RESULTS

PARACOR-19 was a single-centre, double-blind RCT of patients with cardiovascular risk factors and a history of COVID-19 infection 4-16 weeks prior to enrolment. Patients were randomized to sacubitril/valsartan (titrated to the maximum dose of 97/103 mg twice daily) versus matching placebo. Co-primary endpoints were change from baseline to 12 weeks in high-sensitivity cardiac troponin T (hs-cTnT) and soluble ST2 (sST2). Exploratory endpoints included change from baseline to 12 weeks in additional circulating biomarkers. Overall, 42 patients were randomized between August 2021 and March 2023 (n = 20 sacubitril/valsartan, n = 22 placebo). Median (25th-75th) time from COVID-19 diagnosis to enrolment was 67 (48-80) days. Median age was 67 (62-71) years, 48% were female, and 91% were White. Compared with placebo, sacubitril/valsartan did not have a significant effect on the co-primary endpoints of change from baseline in hs-TnT and sST2 (all p ≥ 0.29). In exploratory analyses, sacubitril/valsartan led to a 46% greater reduction in N-terminal pro-B-type natriuretic peptide (NT-proBNP) and 51% greater reduction in C-terminal telopeptide of collagen type I (CITP). Permanent drug discontinuation occurred in four patients in the sacubitril/valsartan group and three patients in the placebo group. There were no deaths and one patient was hospitalized in each group.

CONCLUSION

In this pilot RCT of patients who recovered from acute COVID-19, sacubitril/valsartan did not lower hs-cTnT or sST2 compared with placebo. Exploratory analyses suggested potential benefits of sacubitril/valsartan on cardiac wall stress and collagen turnover as measured by NT-proBNP and CITP. Sacubitril/valsartan was well tolerated.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov NCT04883528.

Current experimental and early investigational agents for cardiac fibrosis: where are we at?

INTRODUCTION

Myocardial fibrosis (MF) is induced by factors activating pro-fibrotic pathways such as acute and prolonged inflammation, myocardial ischemic events, hypertension, aging process, and genetically-linked cardiomyopathies. Dynamics and characteristics of myocardial fibrosis development are very different. The broad range of myocardial fibrosis presentations suggests the presence of multiple potential targets.

AREA COVERED

Heart failure treatment involves medications primarily aimed at counteracting neurohormonal activation. While these drugs have demonstrated efficacy against MF, not all specifically target inflammation or fibrosis progression with some exceptions such as RAAS inhibitors. Consequently, new therapies are being developed to address this issue. This article is aimed to describe anti-fibrotic drugs currently employed in clinical practice and emerging agents that target specific pathways, supported by evidence from both preclinical and clinical studies.

EXPERT OPINION

Despite various preclinical findings suggesting the potential utility of new drugs and molecules for treating cardiac fibrosis in animal models, there is a notable scarcity of clinical trials investigating these effects. However, the pathology of damage and repair in the heart muscle involves a complex network of interconnected inflammatory pathways and various types of immune cells. Our comprehension of the positive and negative roles played by specific immune cells and cytokines is an emerging area of research.

Heart failure with preserved ejection fraction: New challenges and new hopes

Heart failure (HF) is a major public health problem affecting millions of adults worldwide. HF with preserved ejection fraction, i.e. > 50 %, (HFpEF) accounts for more than half of all HF cases, and its incidence and prevalence are increasing with the aging of the population and the growing prevalence of metabolic disorders such as obesity, diabetes and hypertension. Diagnosis of HFpEF requires a combination of numerous echocardiographic parameters and also results of natriuretic peptide assays, to which may be added the need for a stress test. HFpEF is characterized by complex, interrelated pathophysiological mechanisms, which must be understood. This complexity probably accounts for the lack of evidence-based medicine compared with HF with reduced EF. Nevertheless, significant progress has been made recently, with a high level of evidence obtained for the SGLT2 inhibitor class on the one hand, and promising data with new drugs targeting more specifically certain mechanisms such as obesity and inflammation on the other.

Effects of empagliflozin on collagen biomarkers in patients with heart failure: Findings from the EMPEROR trials

AIMS

Extracellular matrix remodelling is one of the key pathways involved in heart failure (HF) progression. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) may have a role in attenuating myocardial fibrosis. The impact of SGLT2i on blood markers of collagen turnover in humans is not fully elucidated. This study aimed to investigate the effect of empagliflozin on serum markers of collagen turnover in patients enrolled in the EMPEROR-Preserved and EMPEROR-Reduced trials.

METHODS AND RESULTS

Overall, 1084 patients (545 in empagliflozin and 539 in placebo) were included in the analysis. Procollagen type I carboxy-terminal propeptide (PICP), a fragment of N-terminal type III collagen (PRO-C3), procollagen type I amino-terminal peptide (PINP), a fragment of C-terminal type VIa3 collagen (PRO-C6), a fragment of type I collagen (C1M), and a fragment of type III collagen (C3M) were measured in serum at baseline, 12 and 52 weeks. A mixed model repeated measurements model was used to evaluate the effect of empagliflozin versus placebo on the analysed biomarkers. Higher baseline PICP, PRO-C6 and PINP levels were associated with older age, a more severe HF presentation, higher levels of natriuretic peptides and high-sensitivity troponin T, and the presence of comorbid conditions such as chronic kidney disease and atrial fibrillation. Higher PICP levels were associated with the occurrence of the study primary endpoint (a composite of HF hospitalization or cardiovascular death), and PRO-C6 and PINP were associated with the occurrence of sustained worsening of kidney function. On the other hand, PRO-C3, C1M, and C3M were not associated with worse HF severity or study outcomes. Compared to placebo, empagliflozin reduced PICP at week 12 by 5% and at week 52 by 8% (week 12: geometric mean ratio = 0.95, 95% confidence interval [CI] 0.91-0.99, p = 0.012; week 52: geometric mean ratio = 0.92, 95% CI 0.88-0.97, p = 0.003). Additionally, empagliflozin reduced PRO-C3 at week 52 by 7% (week 12: geometric mean ratio = 0.98, 95% CI 0.95-1.02, p = 0.42; week 52: geometric mean ratio = 0.93, 95% CI 0.89-0.98, p = 0.003), without impact on other collagen markers.

CONCLUSION

Our observations are consistent with experimental observations that empagliflozin down-regulates profibrotic signalling. The importance of such an effect for the clinical benefits of SGLT2i in HF remains to be elucidated.

Fibroblast activation protein: Pivoting cancer/chemotherapeutic insight towards heart failure

An important mechanism for cancer progression is degradation of the extracellular matrix (ECM) which is accompanied by the emergence and proliferation of an activated fibroblast, termed the cancer associated fibroblast (CAF). More specifically, an enzyme pathway identified to be amplified with local cancer progression and proliferation of the CAF, is fibroblast activation protein (FAP). The development and progression of heart failure (HF) irrespective of the etiology is associated with left ventricular (LV) remodeling and changes in ECM structure and function. As with cancer, HF progression is associated with a change in LV myocardial fibroblast growth and function, and expresses a protein signature not dissimilar to the CAF. The overall goal of this review is to put forward the postulate that scientific discoveries regarding FAP in cancer as well as the development of specific chemotherapeutics could be pivoted to target the emergence of FAP in the activated fibroblast subtype and thus hold translationally relevant diagnostic and therapeutic targets in HF.

Sacubitril/valsartan attenuates myocardial inflammation, hypertrophy, and fibrosis in rats with heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) represents a multifaceted syndrome related to complex pathologic mechanisms. Sacubitril/valsartan (Sac/val) has demonstrated therapeutic efficacy in HFpEF treatment. However, additional research is required to elucidate its pharmacological mechanisms. Accordingly, this study aimed to explore the potential therapeutic effects of Sac/val in HFpEF rats and the underlying molecular mechanisms. In this study, rats with HFpEF were induced by subjecting spontaneously hypertensive rats to a diet rich in fats, salts, and sugars, along with administering streptozotocin. Subsequently, they were administered Sac/val at a daily dosage of 18 mg/kg. Finally, cardiac structure and function were assessed using echocardiography; Hematoxylin and eosin staining and Masson's trichrome staining were employed to evaluate the pathological changes; Quantitative real-time polymerase chain reaction and Western blot analysis were conducted to determine the expression of pertinent mRNA and proteins. Sac/val treatment attenuated left ventricular (LV) remodeling and diastolic dysfunction in HFpEF rats, possibly related to its anti-inflammatory, anti-hypertrophic, and anti-fibrotic efficacy. Mechanistically, Sac/val might inhibit inflammation by down-regulating cell adhesion molecule (intercellular adhesion molecule-1 (ICAM-1) and vascular endothelial cell adhesion molecule-1 (VCAM-1)) expression. Additionally, it blocked the phosphorylation of glycogen synthase kinase 3β (GSK-3β) to prevent cardiomyocyte hypertrophy. Furthermore, it effectively suppressed myocardial fibrosis by inhibiting the transforming growth factor-beta1 (TGF-β1)/Smads pathway. Our findings suggest that Sac/val improved LV remodeling and diastolic dysfunction, potentially attributed to its anti-inflammatory, anti-hypertrophic, and anti-fibrotic effects. These results provide a sound theoretical rationale for the clinical application of Sac/val in patients with HFpEF.

Soluble ST2 in Heart Failure: A Clinical Role beyond B-Type Natriuretic Peptide

Soluble (s)ST2 has been proposed as a useful biomarker for heart failure (HF) patient management. Myocardial damage or mechanical stress stimulate sST2 release. ST2 competes with a membrane bound receptor (ST2 ligand, or ST2L) for interleukin-33 (IL-33) binding, inhibiting the effects induced by the ST2L/IL-33 interaction so that excessive sST2 may contribute to myocardial fibrosis and ventricular remodeling. Compared to natriuretic peptides (NPs), sST2 concentration is not substantially affected by age, sex, body mass index, kidney function, atrial fibrillation, anemia, or HF etiology, and has low intra-individual variation. Its prognostic role as an independent marker is well reported in the literature. However, there is a gap on its use in combination with NPs, currently the only biomarkers recommended by European and American guidelines for HF management. Reflecting the activation of two distinct biological systems, a benefit from the use of sST2 and NP in combination is advocated. The aim of this review is to report the current scientific knowledge on sST2 in the acute and chronic HF settings with a particular attention to its additive role to natriuretic peptides (NPs).

Current challenges in the treatment of cardiac fibrosis: Recent insights into the sex-specific differences of glucose-lowering therapies on the diabetic heart: IUPHAR Review 33

A significant cardiac complication of diabetes is cardiomyopathy, a form of ventricular dysfunction that develops independently of coronary artery disease, hypertension and valvular diseases, which may subsequently lead to heart failure. Several structural features underlie the development of diabetic cardiomyopathy and eventual diabetes-induced heart failure. Pathological cardiac fibrosis (interstitial and perivascular), in addition to capillary rarefaction and myocardial apoptosis, are particularly noteworthy. Sex differences in the incidence, development and presentation of diabetes, heart failure and interstitial myocardial fibrosis have been identified. Nevertheless, therapeutics specifically targeting diabetes-associated cardiac fibrosis remain lacking and treatment approaches remain the same regardless of patient sex or the co-morbidities that patients may present. This review addresses the observed anti-fibrotic effects of newer glucose-lowering therapies and traditional cardiovascular disease treatments, in the diabetic myocardium (from both preclinical and clinical contexts). Furthermore, any known sex differences in these treatment effects are also explored. LINKED ARTICLES: This article is part of a themed issue on Translational Advances in Fibrosis as a Therapeutic Target. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v180.22/issuetoc.

Cardiac Fibrosis in heart failure: Focus on non-invasive diagnosis and emerging therapeutic strategies

Heart failure is a leading cause of mortality and hospitalization worldwide. Cardiac fibrosis, resulting from the excessive deposition of collagen fibers, is a common feature across the spectrum of conditions converging in heart failure. Eventually, either reparative or reactive in nature, in the long-term cardiac fibrosis contributes to heart failure development and progression and is associated with poor clinical outcomes. Despite this, specific cardiac antifibrotic therapies are lacking, making cardiac fibrosis an urgent unmet medical need. In this context, a better patient phenotyping is needed to characterize the heterogenous features of cardiac fibrosis to advance toward its personalized management. In this review, we will describe the different phenotypes associated with cardiac fibrosis in heart failure and we will focus on the potential usefulness of imaging techniques and circulating biomarkers for the non-invasive characterization and phenotyping of this condition and for tracking its clinical impact. We will also recapitulate the cardiac antifibrotic effects of existing heart failure and non-heart failure drugs and we will discuss potential strategies under preclinical development targeting the activation of cardiac fibroblasts at different levels, as well as targeting additional extracardiac processes.

Procollagen type 1 N-terminal propeptide is associated with adverse outcome in acute chest pain of suspected coronary origin

Background

Extracellular matrix (ECM) is an integral player in the pathophysiology of a variety of cardiac diseases. Cardiac ECM is composed mainly of collagen, of which type 1 is the most abundant with procollagen type 1 N-terminal Propeptide (P1NP) as a formation marker. P1NP is associated with mortality in the general population, however, its role in myocardial infarction (MI) is still uncertain, and P1NP has not been investigated in acute chest pain. The objective of the current study was to assess the role of P1NP in undifferentiated acute chest pain of suspected coronary origin.

Methods and results

813 patients from the Risk in Acute Coronary Syndromes study were included. This was a single-center study investigating biomarkers in consecutively enrolled patients with acute chest pain of suspected coronary origin, with a follow-up for up to 7 years. Outcome measures were a composite endpoint of all-cause death, new MI or stroke, as well as its individual components at 1, 2, and 7 years, and cardiac death at 1 and 2 years. In multivariable Cox regression analysis, quartiles of P1NP were significantly associated with the composite endpoint at 1 year of follow-up with a hazard ratio for Q4 of 1.82 (95% CI, 1.12-2.98). There was no other significant association with outcomes at any time points.

Conclusion

P1NP was found to be an independent biomarker significantly associated with adverse clinical outcome at one year in patients admitted to hospital for acute chest pain of suspected coronary origin. This is the first report in the literature on the prognostic value of P1NP in this clinical setting.

Clinicaltrialsygov Identifier

NCT00521976.

Inflammatory Mechanisms in Heart Failure with Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is now the most common form of heart failure and a significant public health concern for which limited effective therapies exist. Inflammation triggered by comorbidity burden is a critical element of HFpEF pathophysiology. Here, we discuss evidence for comorbidity-driven systemic and myocardial inflammation and the mechanistic role of inflammation in pathological myocardial remodeling in HFpEF.

Left Ventricular Gene Expression in Heart Failure With Preserved Ejection Fraction-Profibrotic and Proinflammatory Pathways and Genes

BACKGROUND

Heart failure with preserved ejection fraction (HFpEF) is increasingly prevalent and has few treatments. The molecular mechanisms and resultant signaling pathways that underlie the development of HFpEF are poorly defined. It has been proposed that activation of proinflammatory pathways plays a role in the development of cardiac fibrosis. The signature of gene expression (transcriptome) of previously validated left ventricular biopsies obtained from patients with HFpEF and matched referent controls allows for an unbiased assessment of proinflammatory and profibrotic signaling pathways and genes.

METHODS

Epicardial left ventricular biopsies from stringently selected HFpEF patients (HFpEF, n=16) and referent control patients (CTR, n=14) were obtained during aortocoronary bypass surgery. The subepicardial myocardium was flash-frozen to build a repository that was parallel-processed for RNA sequencing to allow for an unsupervised in-depth comparison of the left ventricular transcriptome.

RESULTS

The average patient age was 67±10 years. When compared with controls, patients with HFpEF were hypertensive with a higher body mass index (kg/m2: 30±5 versus 37±6; P<0.01) and elevated NT-proBNP levels (pg/mL: 155 [89-328] versus 1554 [888-2178]; P<0.001). The transcriptome analysis revealed differential expression of 477 genes many of which were involved in profibrotic pathways including extracellular matrix production and posttranslational modification but no proinflammatory signature.

CONCLUSIONS

The transcriptome analysis of left ventricular myocardial samples from patients with HFpEF confirms an overabundant extracellular matrix gene expression, the basis of myocardial fibrosis, without a signature of activated proinflammatory pathways or genes.

Colchicine in patients with heart failure and preserved left ventricular ejection fraction: rationale and design of a prospective, randomised, open-label, crossover clinical trial

INTRODUCTION

Systemic low-grade inflammation is a fundamental pathophysiological mechanism of heart failure with preserved left ventricular ejection fraction (HFpEF). The efficacy of anti-inflammatory therapy in HFpEF is largely understudied. The aim of the study is to assess the anti-inflammatory effect of colchicine in HFpEF by looking at inflammatory biomarkers: high-sensitivity C reactive protein (hsCRP) and soluble suppression of tumorigenicity 2 (sST2).

METHODS AND ANALYSIS

This is a single-centre, prospective, randomised controlled, open-label, blinded-endpoint crossover clinical trial of stable but symptomatic patients with HFpEF. Patients will be randomised to either colchicine treatment 0.5 mg two times per day or usual care for 12 weeks followed by a 2-week washout period and crossover to 12 weeks of treatment with the alternate therapy. The primary objective is to investigate if administration of colchicine compared with usual care reduces inflammation in patients with HFpEF measured by primary endpoint sST2 and co-primary endpoint hsCRP at baseline and 12-week follow-up. Secondary objective is to determine if treatment with colchicine influences N-terminal pro-B-type natriuretic peptide levels, left ventricular diastolic function and remodelling, right ventricular systolic function and left atrial volumetric characteristics. We are aiming to enrol a total of 40 participants. This trial will answer the question if colchicine treatment reduces systemic low-grade inflammation and influences left ventricular diastolic function and remodelling with patients with HFpEF.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the Ethics Committee of Sechenov University (reference: 03-22).

TRIAL REGISTRATION NUMBER

NCT05637398.

The Microenvironment of the Pathogenesis of Cardiac Hypertrophy

Pathological cardiac hypertrophy is a key risk factor for the development of heart failure and predisposes individuals to cardiac arrhythmia and sudden death. While physiological cardiac hypertrophy is adaptive, hypertrophy resulting from conditions comprising hypertension, aortic stenosis, or genetic mutations, such as hypertrophic cardiomyopathy, is maladaptive. Here, we highlight the essential role and reciprocal interactions involving both cardiomyocytes and non-myocardial cells in response to pathological conditions. Prolonged cardiovascular stress causes cardiomyocytes and non-myocardial cells to enter an activated state releasing numerous pro-hypertrophic, pro-fibrotic, and pro-inflammatory mediators such as vasoactive hormones, growth factors, and cytokines, i.e., commencing signaling events that collectively cause cardiac hypertrophy. Fibrotic remodeling is mediated by cardiac fibroblasts as the central players, but also endothelial cells and resident and infiltrating immune cells enhance these processes. Many of these hypertrophic mediators are now being integrated into computational models that provide system-level insights and will help to translate our knowledge into new pharmacological targets. This perspective article summarizes the last decades' advances in cardiac hypertrophy research and discusses the herein-involved complex myocardial microenvironment and signaling components.

Porcupine inhibitor CGX1321 alleviates heart failure with preserved ejection fraction in mice by blocking WNT signaling

Heart failure with preserved ejection fraction (HFpEF) is highly prevalent, and lacks effective treatment. The aberration of WNT pathway underlies many pathological processes including cardiac fibrosis and hypertrophy, while porcupine is an acyltransferase essential for the secretion of WNT ligands. In this study we investigated the role of WNT signaling pathway in HFpEF as well as whether blocking WNT signaling by a novel porcupine inhibitor CGX1321 alleviated HFpEF. We established two experimental HFpEF mouse models, namely the UNX/DOCA model and high fat diet/L-NAME ("two-hit") model. The UNX/DOCA and "two-hit" mice were treated with CGX1321 (3 mg·kg-1·d-1) for 4 and 10 weeks, respectively. We showed that CGX1321 treatment significantly alleviated cardiac hypertrophy and fibrosis, thereby improving cardiac diastolic function and exercise performance in both models. Furthermore, both canonical and non-canonical WNT signaling pathways were activated, and most WNT proteins, especially WNT3a and WNT5a, were upregulated during the development of HEpEF in mice. CGX1321 treatment inhibited the secretion of WNT ligands and repressed both canonical and non-canonical WNT pathways, evidenced by the reduced phosphorylation of c-Jun and the nuclear translocation of β-catenin and NFATc3. In an in vitro HFpEF model, MCM and ISO-treated cardiomyocytes, knockdown of porcupine by siRNA leads to a similar inhibitory effect on WNT pathways, cardiomyocyte hypertrophy and cardiac fibroblast activation as CGX1321 did, whereas supplementation of WNT3a and WNT5a reversed the anti-hypertrophy and anti-fibrosis effect of CGX1321. We conclude that WNT signaling activation plays an essential role in the pathogenesis of HFpEF, and porcupine inhibitor CGX1321 exerts a therapeutic effect on HFpEF in mice by attenuating cardiac hypertrophy, alleviating cardiac fibrosis and improving cardiac diastolic function.

Proteomic Pathways across Ejection Fraction Spectrum in Heart Failure: an EXSCEL Substudy

Background

Ejection fraction (EF) is a key component of heart failure (HF) classification, including the increasingly codified HF with mildly reduced EF (HFmrEF) category. However, the biologic basis of HFmrEF as an entity distinct from HF with preserved EF (HFpEF) and reduced EF (HFrEF) has not been well characterized.

Methods

The EXSCEL trial randomized participants with type 2 diabetes (T2DM) to once-weekly exenatide (EQW) vs. placebo. For this study, profiling of ∼5000 proteins using the SomaLogic SomaScan platform was performed in baseline and 12-month serum samples from N=1199 participants with prevalent HF at baseline. Principal component analysis (PCA) and ANOVA (FDR p<0.1) were used to determine differences in proteins between three EF groups, as previously curated in EXSCEL (EF>55% [HFpEF], EF 40-55% [HFmrEF], EF<40% [HFrEF]). Cox proportional hazards was used to assess association between baseline levels of significant proteins, and changes in protein level between baseline and 12-month, with time-to-HF hospitalization. Mixed models were used to assess whether significant proteins changed differentially with exenatide vs. placebo therapy.

Results

Of N=1199 EXSCEL participants with prevalent HF, 284 (24%), 704 (59%) and 211 (18%) had HFpEF, HFmrEF and HFrEF, respectively. Eight PCA protein factors and 221 individual proteins within these factors differed significantly across the three EF groups. Levels of the majority of proteins (83%) demonstrated concordance between HFmrEF and HFpEF, but higher levels in HFrEF, predominated by the domain of extracellular matrix regulation, e.g. COL28A1 and tenascin C [TNC]; p<0.0001. Concordance between HFmrEF and HFrEF was observed in a minority of proteins (1%) including MMP-9 (p<0.0001). Biologic pathways of epithelial mesenchymal transition, ECM receptor interaction, complement and coagulation cascades, and cytokine receptor interaction demonstrated enrichment among proteins with the dominant pattern, i.e. HFmrEF-HFpEF concordance. Baseline levels of 208 (94%) of the 221 proteins were associated with time-to-incident HF hospitalization including domains of extracellular matrix (COL28A1, TNC), angiogenesis (ANG2, VEGFa, VEGFd), myocyte stretch (NT-proBNP), and renal function (cystatin-C). Change in levels of 10 of the 221 proteins from baseline to 12 months (including increase in TNC) predicted incident HF hospitalization (p<0.05). Levels of 30 of the 221 significant proteins (including TNC, NT-proBNP, ANG2) were reduced differentially by EQW compared with placebo (interaction p<0.0001).

Conclusions

In this HF substudy of a large clinical trial of people with T2DM, we found that serum levels of most proteins across multiple biologic domains were similar between HFmrEF and HFpEF. HFmrEF may be more biologically similar to HFpEF than HFrEF, and specific related biomarkers may offer unique data on prognosis and pharmacotherapy modification with variability by EF.

The history and mystery of sacubitril/valsartan: From clinical trial to the real world

Heart failure is a serious threat to human health, with morbidity and mortality rates increasing despite the existence of multiple treatment options. Therefore, it is necessary to identify new therapeutic targets for this disease. Sacubitril/valsartan is a supramolecular sodium salt complex of the enkephalinase inhibitor prodrug sacubitril and the angiotensin receptor blocker valsartan. Its combined action increases endogenous natriuretic peptides while inhibiting the renin-angiotensin-aldosterone system and exerting cardioprotective effects. Clinical evidence suggests that sacubitril/valsartan is superior to conventional renin-angiotensin-aldosterone inhibitor therapy for patients with reduced ejection fraction heart failure who can tolerate angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers. The therapy reduces the risk of heart failure hospitalization, cardiovascular mortality, and all-cause mortality and has a better safety and tolerability record. This review describes the potential pathophysiological mechanisms of cardiomyocyte injury amelioration by sacubitril/valsartan. We explore the protective effects of sacubitril/valsartan and outline the therapeutic value in patients with heart failure by summarizing the results of recent large clinical trials. Furthermore, a preliminary outlook shows that sacubitril/valsartan may be effective at treating other diseases, and provides some exploratory observations that lay the foundation for future studies on this drug.

WGCNA combined with machine learning algorithms for analyzing key genes and immune cell infiltration in heart failure due to ischemic cardiomyopathy

Background

Ischemic cardiomyopathy (ICM) induced heart failure (HF) is one of the most common causes of death worldwide. This study aimed to find candidate genes for ICM-HF and to identify relevant biomarkers by machine learning (ML).

Methods

The expression data of ICM-HF and normal samples were downloaded from Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) between ICM-HF and normal group were identified. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment and gene ontology (GO) annotation analysis, protein–protein interaction (PPI) network, gene pathway enrichment analysis (GSEA), and single-sample gene set enrichment analysis (ssGSEA) were performed. Weighted gene co-expression network analysis (WGCNA) was applied to screen for disease-associated modules, and relevant genes were derived using four ML algorithms. The diagnostic values of candidate genes were assessed using receiver operating characteristic (ROC) curves. The immune cell infiltration analysis was performed between the ICM-HF and normal group. Validation was performed using another gene set.

Results

A total of 313 DEGs were identified between ICM-HF and normal group of GSE57345, which were mainly enriched in biological processes and pathways related to cell cycle regulation, lipid metabolism pathways, immune response pathways, and intrinsic organelle damage regulation. GSEA results showed positive correlations with pathways such as cholesterol metabolism in the ICM-HF group compared to normal group and lipid metabolism in adipocytes. GSEA results also showed a positive correlation with pathways such as cholesterol metabolism and a negative correlation with pathways such as lipolytic presentation in adipocytes compared to normal group. Combining multiple ML and cytohubba algorithms yielded 11 relevant genes. After validation using the GSE42955 validation sets, the 7 genes obtained by the machine learning algorithm were well verified. The immune cell infiltration analysis showed significant differences in mast cells, plasma cells, naive B cells, and NK cells.

Conclusion

Combined analysis using WGCNA and ML identified coiled-coil-helix-coiled-coil-helix domain containing 4 (CHCHD4), transmembrane protein 53 (TMEM53), acid phosphatase 3 (ACPP), aminoadipate-semialdehyde dehydrogenase (AASDH), purinergic receptor P2Y1 (P2RY1), caspase 3 (CASP3) and aquaporin 7 (AQP7) as potential biomarkers of ICM-HF. ICM-HF may be closely related to pathways such as mitochondrial damage and disorders of lipid metabolism, while the infiltration of multiple immune cells was identified to play a critical role in the progression of the disease.

In Search of the Holy Grail: Stem Cell Therapy as a Novel Treatment of Heart Failure with Preserved Ejection Fraction

Heart failure, a leading cause of hospitalizations and deaths, is a major clinical problem. In recent years, the increasing incidence of heart failure with preserved ejection fraction (HFpEF) has been observed. Despite extensive research, there is no efficient treatment for HFpEF available. However, a growing body of evidence suggests stem cell transplantation, due to its immunomodulatory effect, may decrease fibrosis and improve microcirculation and therefore, could be the first etiology-based therapy of the disease. In this review, we explain the complex pathogenesis of HFpEF, delineate the beneficial effects of stem cells in cardiovascular therapy, and summarize the current knowledge concerning cell therapy in diastolic dysfunction. Furthermore, we identify outstanding knowledge gaps that may indicate directions for future clinical studies.

Heart Failure with Preserved Ejection Fraction in Children

Diastolic dysfunction (DD) refers to abnormalities in the mechanical function of the left ventricle (LV) during diastole. Severe LVDD can cause symptoms and the signs of heart failure (HF) in the setting of normal or near normal LV systolic function and is referred to as diastolic HF or HF with preserved ejection fraction (HFpEF). Pediatric cardiologists have long speculated HFpEF in children with congenital heart disease and cardiomyopathy. However, understanding the risk factors, clinical course, and validated biomarkers predictive of the outcome of HFpEF in children is challenging due to heterogeneous etiologies and overlapping pathophysiological mechanisms. The natural history of HFpEF varies depending upon the patient's age, sex, race, geographic location, nutritional status, biochemical risk factors, underlying heart disease, and genetic-environmental interaction, among other factors. Pediatric onset HFpEF is often not the same disease as in adults. Advances in the noninvasive evaluation of the LV diastolic function by strain, and strain rate analysis with speckle-tracking echocardiography, tissue Doppler imaging, and cardiac magnetic resonance imaging have increased our understanding of the HFpEF in children. This review addresses HFpEF in children and identifies knowledge gaps in the underlying etiologies, pathogenesis, diagnosis, and management, especially compared to adults with HFpEF.

Inflammatory pathways in heart failure with preserved left ventricular ejection fraction: implications for future interventions

Many patients with symptoms and signs of heart failure have a left ventricular ejection fraction ≥50%, termed heart failure with preserved ejection fraction (HFpEF). HFpEF is a heterogeneous syndrome mainly affecting older people who have many other cardiac and non-cardiac conditions that often cast doubt on the origin of symptoms, such as breathlessness, or signs, such as peripheral oedema, rendering them neither sensitive nor specific to the diagnosis of HFpEF. Currently, management of HFpEF is mainly directed at controlling symptoms and treating comorbid conditions such as hypertension, atrial fibrillation, anaemia, and coronary artery disease. HFpEF is also characterized by a persistent increase in inflammatory biomarkers. Inflammation may be a key driver of the development and progression of HFpEF and many of its associated comorbidities. Detailed characterization of specific inflammatory pathways may provide insights into the pathophysiology of HFpEF and guide its future management. There is growing interest in novel therapies specifically designed to target deregulated inflammation in many therapeutic areas, including cardiovascular disease. However, large-scale clinical trials investigating the effectiveness of anti-inflammatory treatments in HFpEF are still lacking. In this manuscript, we review the role of inflammation in HFpEF and the possible implications for future trials.

Preclinical scenario of targeting myocardial fibrosis with chimeric antigen receptor (CAR) immunotherapy

Fibrosis is present in an important proportion of myocardial disorders. Injury activates cardiac fibroblasts, which deposit excess extracellular matrix, increasing tissue stiffness, impairing cardiac function, and leading to heart failure. Clinical therapies that directly target excessive fibrosis are limited, and more effective treatments are needed. Immunotherapy based on chimeric antigen receptor (CAR) T cells is a novel technique that redirects T lymphocytes toward specific antigens to eliminate the target cells. It is currently used in haematological cancers but has demonstrated efficacy in mouse models of hypertensive cardiac fibrosis, with activated fibroblasts as the target cells. CAR T cell therapy is associated with significant toxicities, but CAR natural killer cells can overcome efficacy and safety limitations. The use of CAR immunotherapy offers a potential alternative to current therapies for fibrosis reduction and restoration of cardiac function in patients with myocardial fibrosis.

Laboratory and Metabolomic Fingerprint in Heart Failure with Preserved Ejection Fraction: From Clinical Classification to Biomarker Signature

Heart failure with preserved ejection fraction (HFpEF) remains a poorly characterized syndrome with many unknown aspects related to different patient profiles, various associated risk factors and a wide range of aetiologies. It comprises several pathophysiological pathways, such as endothelial dysfunction, myocardial fibrosis, extracellular matrix deposition and intense inflammatory system activation. Until now, HFpEF has only been described with regard to clinical features and its most commonly associated risk factors, disregarding all biological mechanisms responsible for cardiovascular deteriorations. Recently, innovations in laboratory and metabolomic findings have shown that HFpEF appears to be strictly related to specific cells and molecular mechanisms' dysregulation. Indeed, some biomarkers are efficient in early identification of these processes, adding new insights into diagnosis and risk stratification. Moreover, recent advances in intermediate metabolites provide relevant information on intrinsic cellular and energetic substrate alterations. Therefore, a systematic combination of clinical imaging and laboratory findings may lead to a 'precision medicine' approach providing prognostic and therapeutic advantages. The current review reports traditional and emerging biomarkers in HFpEF and it purposes a new diagnostic approach based on integrative information achieved from risk factor burden, hemodynamic dysfunction and biomarkers' signature partnership.

Effects of sacubitril/valsartan on cardiac reverse remodeling and cardiac resynchronization in patients with acute myocardial infarction

Introduction

In 2014, the PARADIGM-HF trial (Prospective Comparison of ARNI with ACEI to Determine Impact on Global Mortality and Morbidity in Heart Failure) has shown that sacubitril/valsartan can reduce the risk of hospitalization and death from cardiovascular causes more effectively than enalapril (an ACEI) in heart failure patients with reduced ejection fraction (HFrEF). Similarly, the PARADIGM-HF trial (Comparison of Sacubitril-Valsartan vs. Enalapril on Effect on NT-proBNP in Patients Stabilized from an Acute Heart Failure Episode) came to similar conclusions and extended the PARADIGM-HF trial results in 2019. Since then, numerous new studies have provided further insight in HFrEF, sacubitril/valsartan can reduce N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels, increase left ventricular ejection fraction (LVEF), reverse ventricular remodeling, and reduce other non-fatal manifestations of clinical deterioration as compared to ACEI/ARB. However, few trials have compared the effects of these drugs in patients shortly after AMI. Therefore, it is necessary to further explore the clinical efficacy and safety of sacubitril/valsartan vs. valsartan in patients with AMI.

Methods

We conducted an open-label, prospective, randomized controlled trial to determine the superiority in ameliorating ventricular remodeling and preventing of heart failure in patients with AMI after percutaneous coronary intervention (PCI), 148 patients were randomly assigned (85 to sacubitril/valsartan and 63 to valsartan).

Results

LAV, LVDV, and LVSV were all decreased in the sacubitril/valsartan group when compared with before treatment, but there was no difference between the sacubitril/valsartan group and the valsartan group. In addition, compared with before treatment in the sacubitril/valsartan group, the heart global work index (GWI) and the global work efficiency (GWE) increased, while the heart global wasted work (GWW) decreased. Patients in the sacubitril/valsartan group have similar MACE and adverse side effects to those in the valsartan group.

Conclusion

Sacubitril/valsartan has the same performance as valsartan in inhibiting ventricular remodeling and preventing heart failure after PCI in patients with AMI, and its clinical application is safe. It provides a clinical foundation for the application of sacubitril/valsartan in patients with AMI.

Management of heart failure with preserved ejection fraction: from neurohormonal antagonists to empagliflozin

Heart failure with preserved ejection fraction (HFpEF) is a highly prevalent syndrome with multifaceted pathophysiology. All approaches to neurohormonal modulation were shown not to improve survival in HFpEF, despite their well-established efficacy in heart failure with reduced ejection fraction (HFrEF). This might be attributed to suboptimal study design, inadequate diagnostic criteria, or statistical power, but is also likely to reflect a lack of consideration for its clinical heterogeneity. The attention then shifted to the phenotypic heterogeneity of HFpEF, with the ultimate goal of developing therapies tailored to individual patient phenotypes. Recently, the sodium-glucose co-transporter-2 inhibitor (SGLT2i) empagliflozin has been found to reduce the combined risk of cardiovascular death or hospitalization for HF in patients with HFpEF, a result driven by a reduction in HF hospitalizations. This paper recapitulates the journey from the failure of trials on neurohormonal antagonists to the attempts of personalized approaches and the new perspectives of SGLT2i therapy for HFpEF.

Treatment of cardiac fibrosis: from neuro-hormonal inhibitors to CAR-T cell therapy

Cardiac fibrosis is characterized by the deposition of extracellular matrix proteins in the spaces between cardiomyocytes following both acute and chronic tissue damage events, resulting in the remodeling and stiffening of heart tissue. Fibrosis plays an important role in the pathogenesis of many cardiovascular disorders, including heart failure and myocardial infarction. Several studies have identified fibroblasts, which are induced to differentiate into myofibroblasts in response to various types of damage, as the most important cell types involved in the fibrotic process. Some drugs, such as inhibitors of the renin-angiotensin-aldosterone system, have been shown to be effective in reducing cardiac fibrosis. There are currently no drugs with primarily anti-fibrotic action approved for clinical use, as well as the evidence of a clinical efficacy of these drugs is extremely limited, despite the numerous encouraging results from experimental studies. A new approach is represented by the use of CAR-T cells engineered in vivo using lipid nanoparticles containing mRNA coding for a receptor directed against the FAP protein, expressed by cardiac myofibroblasts. This strategy has proved to be safe and effective in reducing myocardial fibrosis and improving cardiac function in mouse models of cardiac fibrosis. Clinical studies are required to test this novel approach in humans.

Assessing clinical and biomarker characteristics to optimize the benefits of sacubitril/valsartan in heart failure

Of the various medical therapies for heart failure (HF), sacubitril/valsartan is a first-in-class angiotensin receptor-neprilysin inhibitor that combines sacubitril, a pro-drug that is further metabolized to the neprilysin inhibitor sacubitrilat, and the angiotensin II type 1 receptor blocker valsartan. Inhibition of neprilysin and blockade of the angiotensin II type 1 receptor with sacubitril/valsartan increases vasoactive peptide levels, increasing vasodilation, natriuresis, and diuresis. Left ventricular ejection fraction (LVEF) is widely used to classify HF, to assist with clinical decision-making, for patient selection in HF clinical trials, and to optimize the benefits of sacubitril/valsartan in HF. However, as HF is a complex syndrome that occurs on a continuum of overlapping and changing phenotypes, patient classification based solely on LVEF becomes problematic. LVEF measurement can be imprecise, have low reproducibility, and often changes over time. LVEF may not accurately reflect inherent disease heterogeneity and complexity, and the addition of alternate criteria to LVEF may improve phenotyping of HF and help guide treatment choices. Sacubitril/valsartan may work, in part, by mechanisms that are not directly related to the LVEF. For example, this drug may exert antifibrotic and neurohumoral modulatory effects through inhibition or activation of several signaling pathways. In this review, we discuss markers of cardiac remodeling, fibrosis, systemic inflammation; activation of neurohormonal pathways, including the natriuretic system and the sympathetic nervous system; the presence of comorbidities; patient characteristics; hemodynamics; and HF signs and symptoms that may all be used to (1) better understand the mechanisms of action of sacubitril/valsartan and (2) help to identify subsets of patients who might benefit from treatment, regardless of LVEF.

Is It Possible to Analyze Kidney Functions, Electrolytes and Volemia Using Artificial Intelligence?

Markers used in everyday clinical practice cannot distinguish between the permanent impairment of renal function. Sodium and potassium values and their interdependence are key parameters in addition to volemia for the assessment of cardiorenal balance. The aim of this study was to investigate volemia and electrolyte status from a clinical cardiorenal viewpoint under consideration of renal function utilizing artificial intelligence. In this paper, an analysis of five variables: B-type natriuretic peptide, sodium, potassium, ejection fraction, EPI creatinine-cystatin C, was performed using an algorithm based on the adaptive neuro fuzzy inference system. B-type natriuretic peptide had the greatest influence on the ejection fraction. It has been shown that values of both Na+ and K+ lead to deterioration of the condition and vital endangerment of patients. To identify the risk of occurrence, the model identifies a prognostic biomarker by random regression from the total data set. The predictions obtained from this model can help optimize preventative strategies and intensive monitoring for patients identified as at risk for electrolyte disturbance and hypervolemia. This approach may be superior to the traditional diagnostic approach due to its contribution to more accurate and rapid diagnostic interpretation and better planning of further patient treatment.

Sacubitril/valsartan alleviates sepsis-induced acute lung injury via inhibiting GSDMD-dependent macrophage pyroptosis in mice

Sepsis-induced acute lung injury (ALI) is a life-threatening disorder with intricate pathogenesis. Macrophage pyroptosis reportedly plays a vital role in ALI. Although it has been established that angiotensin receptor blockers (ARBs) can reduce sepsis-induced organ injury, the efficacy of sacubitril/valsartan (SV) for sepsis has been largely understudied. Here, we aimed to investigate the role of SV in sepsis-induced ALI. Caecal ligation and puncture (CLP) were used to induce polymicrobial sepsis and related ALI. The therapeutic effects of SV in CLP mice were subsequently assessed. Gasdermin D (GSDMD)^-/- mice were used to validate the signalling pathways affected by SV. In vitro, mouse bone marrow-derived macrophages (BMDMs) and Raw264.7 cells were treated with SV following exposure to lipopolysaccharide and adenosine triphosphate. Finally, the serum obtained from 42 septic patients was used for biochemical analysis. Compared to the other ARBs, SV yielded more pronounced anti-inflammatory effects on macrophages. In vivo, SV decreased mortality rates, significantly reduced lung damage and prevented the inflammatory response in CLP mice. In addition, SV suppressed GSDMD-mediated macrophage pyroptosis in mice. In BMDMs and Raw264.7 cells, the anti-inflammatory and anti-pyroptosis properties of SV were verified. SV treatment effectively inhibited NLRP3 inflammasome activation and prevented macrophage pyroptosis in a GSDMD-dependent manner. Furthermore, we found that septic individuals had considerably higher serum angiotensin II levels. Overall, we found that SV might prevent ALI in CLP mice by inhibiting GSDMD-mediated pyroptosis of macrophages. Thus, SV might be a viable drug for sepsis-induced ALI.

Heart Failure with Improved Ejection Fraction: Insight into the Variable Nature of Left Ventricular Systolic Function

The progress of contemporary cardiovascular therapy has led to improved survival in patients with myocardial disease. However, the development of heart failure (HF) represents a common clinical challenge, regardless of the underlying myocardial pathology, due to the severely impaired quality of life and increased mortality comparable with malignant neoplasms. Left ventricular ejection fraction (LVEF) is the main index of systolic function and a key predictor of mortality among HF patients, hence its improvement represents the main indicator of response to instituted therapy. The introduction of complex pharmacotherapy for HF, increased availability of cardiac-implantable electronic devices and advances in the management of secondary causes of HF, including arrhythmia-induced cardiomyopathy, have led to significant increase in the proportion of patients with prominent improvement or even normalization of LVEF, paving the way for the identification of a new subgroup of HF with an improved ejection fraction (HFimpEF). Accumulating data has indicated that these patients share far better long-term prognoses than patients with stable or worsening LVEF. Due to diverse HF aetiology, the prevalence of HFimpEF ranges from roughly 10 to 40%, while the search for reliable predictors and genetic associations corresponding with this clinical presentation is under way. As contemporary guidelines focus mainly on the management of HF patients with clearly defined LVEF, the present review aimed to characterize the definition, epidemiology, predictors, clinical significance and principles of therapy of patients with HFimpEF.

Diagnostic and prognostic value of serum soluble suppression of tumorigenicity-2 in heart failure with preserved ejection fraction: A systematic review and meta-analysis

Background

Heart failure (HF) with preserved ejection fraction (HFpEF) is a growing public health burden, with mortality and rehospitalization rates comparable to HF with reduced ejection fraction (HFrEF). The evidence for the clinical usefulness of soluble suppression of tumorigenicity 2 (sST2) in HFpEF is contradictory. Therefore, we conducted the following systematic review and meta-analysis to assess the diagnostic and prognostic value of serum sST2 in HFpEF.

Methods

PubMed and Scopus were searched exhaustively from their inception until March 15, 2022. In diagnostic analysis, we compared the diagnostic value of serum sST2 in HFpEF to NT pro-BNP. We separately pooled the unadjusted and multivariate-adjusted hazard ratios (HRs) and the corresponding 95% confidence intervals (CIs) in prognostic analysis.

Results

A total of 16 publications from 2008 to 2021 were examined. The results of this analysis were as follow: Firstly, compared with NT pro-BNP, sST2 obtains poor diagnostic performance in independently identifying HFpEF from healthy controls, hypertensive patients, and HFrEF patient. Nevertheless, it may provide incremental value to other biomarkers for diagnosing HFpEF and deserves further investigation. Secondly, log sST2 was independently associated with adverse endpoints on multivariable analysis after adjusting for variables such as age, sex, race, and NYHA class. Per log unit rise in sST2, there was a 2.76-fold increased risk of all-cause death [HR:2.76; 95% CI (1.24, 6.16); p = 0.516, I² = 0%; P = 0.013] and a 6.52-fold increased risk in the composite endpoint of all-cause death and HF hospitalization [HR:6.52; 95% CI (2.34, 18.19); p = 0.985, I² = 0%; P = 0.000]. Finally, the optimal threshold levels of serum sST2 need further determined.

Conclusions

Higher sST2 was strongly linked to an increased risk of adverse outcomes in HFpEE. Especially, log sST2 independently predicted all-cause death and the composite endpoint of all-cause death and HF hospitalization. However, prospective and multicenter studies with large-sample and extended follow-up periods are required to validate our results due to limitations in our research.

Angiotensin-neprilysin inhibition and renal outcomes across the spectrum of ejection fraction in heart failure

AIMS

Patients with heart failure are at higher risk of progression to end-stage renal disease (ESRD), regardless of ejection fraction (EF). We assessed the renal effects of angiotensin-neprilysin inhibition in a pooled analysis of 13 195 patients with heart failure with reduced and preserved EF.

METHODS AND RESULTS

We combined data from PARADIGM-HF (EF ≤40%; n = 8399) and PARAGON-HF (EF ≥45%; n = 4796) in a pre-specified pooled analysis. We assessed the effect of treatment (sacubitril/valsartan vs. enalapril or valsartan) on a composite of either ≥50% reduction in estimated glomerular filtration rate (eGFR), ESRD, or death from renal causes, in addition to changes in eGFR slope. We assessed whether baseline renal function or EF modified the effect of therapy on renal outcomes. At randomization, eGFR was 68 ± 20 ml/min/1.73 m2 in PARADIGM-HF and 63 ± 19 ml/min/1.73 m2 in PARAGON-HF. The composite renal outcome occurred in 70 of 6594 patients (1.1%) in the sacubitril/valsartan group and in 123 of 6601 patients (1.9%) in the valsartan or enalapril group (hazard ratio 0.56, 95% confidence interval [CI] 0.42-0.75; p < 0.001). The mean eGFR change was -1.8 (95% CI -1.9 to -1.7) ml/min/1.73 m2 /year for the sacubitril/valsartan group, compared with -2.4 (95% CI -2.5 to -2.2) ml/min/1.73 m2 /year for the valsartan or enalapril group. The treatment effect on the composite renal endpoint was not modified by categories of baseline eGFR (p-interaction = 0.64), but was most pronounced in those with baseline EF between 30% and 60% (p-interaction = 0.001).

CONCLUSIONS

In patients with heart failure, sacubitril/valsartan reduced the risk of serious adverse renal outcomes and slowed decline in eGFR, compared with valsartan or enalapril, independent of baseline renal function.

Efficacy and safety of sacubitril/valsartan vs. valsartan in patients with acute myocardial infarction: A meta-analysis

Background

The angiotensin-receptor neprilysin inhibitor (ARNI) sacubitril/valsartan was shown to be superior to the angiotensin receptor blocker (ARB) valsartan in terms of reversing heart failure classification (NYHA classification), reducing N-terminal pro-brain natriuretic peptide (NT-proBNP) level and cardiovascular mortality in many studies. Yet, the efficacy of ARNI did not come from patients with acute myocardial infarction (AMI).

Methods

We searched databases for research published from inception to July 29, 2022, that reported cardiac reverse remodeling (CRR) or security indices. Two reviewers independently screened literature, extracted data, and assessed the risk of bias. Nine studies enrolling 1,369 patients were included to perform a meta-analysis. There were 716 patients in the ARNI group and 653 in the ARB group.

Results

ARNI outperformed ARBs in terms of CRR indices, with striking changes in left ventricular ejection fraction (EF) (MD: 4.12%, 95%CI: 2.36, 5.88, P &lt; 0.0001), diameter (MD: –3.40 mm, 95%CI: –4.30, –2.94, P &lt; 0.00001, I2 = 0%) and left atrial diameter (MD: –2.41 mm, 95%CI: –3.85, –0.97, P = 0.001, I2 = 0%), other indices there showed no significant improvements. The incidences of major adverse cardiac events (RR: 0.47, 95%CI: 0.34–0.65, P &lt; 0.00001, I2 = 0%), the heart failure (RR: 0.37, 95%CI: 0.23–0.61, P &lt; 0.0001, I2 = 0%), readmission (RR: 0.54, 95%CI: 0.36–0.80, P = 0.003, I2 = 29%) in the sacubitril/valsartan group were lower than the ARB group, while the incidences of cardiac death (RR: 0.56, 95%CI: 0.28, 1.09, P = 0.09), the myocardial infarction (RR: 0.83, 95% CI: 0.39, 1.77, P = 0.63), adverse side effects (RR: 1.67, 95% CI: 0.89, 3.13, P = 0.11) showed no difference.

Conclusion

This research indicated that early initiation of sacubitril/valsartan in patients after AMI was superior to ARBs in reducing the risks of major adverse cardiac events, heart failure, readmission, and enhancing left ventricular EF, decreasing diameter, left atrial diameter. As for the other outcomes (the incidences of cardiac death, myocardial infarction, and adverse side effects), sacubitril/valsartan demonstrated no obvious advantage over ARBs.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier [CRD42022307237].

Molecular mechanisms of sacubitril/valsartan in cardiac remodeling

Cardiovascular diseases have become a major clinical burden globally. Heart failure is one of the diseases that commonly emanates from progressive uncontrolled hypertension. This gives rise to the need for a new treatment for the disease. Sacubitril/valsartan is a new drug combination that has been approved for patients with heart failure. This review aims to detail the mechanism of action for sacubitril/valsartan in cardiac remodeling, a cellular and molecular process that occurs during the development of heart failure. Accumulating evidence has unveiled the cardioprotective effects of sacubitril/valsartan on cellular and molecular modulation in cardiac remodeling, with recent large-scale randomized clinical trials confirming its supremacy over other traditional heart failure treatments. However, its molecular mechanism of action in cardiac remodeling remains obscure. Therefore, comprehending the molecular mechanism of action of sacubitril/valsartan could help future research to study the drug's potential therapy to reduce the severity of heart failure.

Aminoacylase-1 plays a key role in myocardial fibrosis and the therapeutic effects of 20(S)-ginsenoside Rg3 in mouse heart failure

We previously found that the levels of metabolite N-acetylglutamine were significantly increased in urine samples of patients with heart failure (HF) and in coronary artery ligation (CAL)-induced HF mice, whereas the expression of its specific metabolic-degrading enzyme aminoacylase-1 (ACY1) was markedly decreased. In the current study, we investigated the role of ACY1 in the pathogenesis of HF and the therapeutic effects of 20(S)-ginsenoside Rg3 in HF experimental models in vivo and in vitro. HF was induced in mice by CAL. The mice were administered Rg3 (7.5, 15, 30 mg · kg^-1· d^-1, i.g.), or positive drug metoprolol (Met, 5.14 mg · kg^-1· d^-1, i.g.), or ACY1 inhibitor mono-tert-butyl malonate (MTBM, 5 mg · kg^-1 · d^-1, i.p.) for 14 days. We showed that administration of MTBM significantly exacerbated CAL-induced myocardial injury, aggravated cardiac dysfunction, and pathological damages, and promoted myocardial fibrosis in CAL mice. In Ang II-induced mouse cardiac fibroblasts (MCFs) model, overexpression of ACY1 suppressed the expression of COL3A1 and COL1A via inhibiting TGF-β1/Smad3 pathway, whereas ACY1-siRNA promoted the cardiac fibrosis responses. We showed that a high dose of Rg3 (30 mg · kg^-1· d^-1) significantly decreased the content of N-acetylglutamine, increased the expression of ACY1, and inhibited TGF-β1/Smad3 pathway in CAL mice; Rg3 (25 μM) exerted similar effects in Ang II-treated MCFs. Meanwhile, Rg3 treatment ameliorated cardiac function and pathological features, and it also attenuated myocardial fibrosis in vivo and in vitro. In Ang II-treated MCFs, the effects of Rg3 on collagen deposition and TGF-β1/Smad3 pathway were slightly enhanced by overexpression of ACY1, whereas ACY1 siRNA partially weakened the beneficial effects of Rg3, suggesting that Rg3 might suppress myocardial fibrosis through ACY1. Our study demonstrates that N-acetylglutamine may be a potential biomarker of HF and its specific metabolic-degrading enzyme ACY1 could be a potential therapeutic target for the prevention and treatment of myocardial fibrosis during the development of HF. Rg3 attenuates myocardial fibrosis to ameliorate HF through increasing ACY1 expression and inhibiting TGF-β1/Smad3 pathway, which provides some references for further development of anti-fibrotic drugs for HF.

[Treatment of patients with heart failure and preserved ejection fraction: reliance on clinical phenotypes]

The article discusses the problem of improving the effectiveness of treatment of heart failure with preserved left ventricular ejection fraction (HFpEF). The relative "failure" of early studies with renin-angiotensin-aldosterone system inhibitors was largely due to the lack of understanding that patients with HFpEF represent a heterogeneous group with various etiological factors and pathogenetic mechanisms of the disease. Therefore, the so-called personalized approach should be used in the treatment of these patients. This approach is based on the identification of clearly defined disease phenotypes, each characterized by a set of demographic, pathogenetic, and clinical characteristics. Based on the literature and own experience, the authors consider four main phenotypes of HFpEF: 1) phenotype with brain natriuretic peptide "deficiency" syndrome associated with moderate/severe left ventricular hypertrophy; 2) cardiometabolic phenotype; 3) phenotype with mixed pulmonary hypertension and right ventricular failure; and 4) cardiac amyloidosis phenotype. In the treatment of patients with phenotype 1, it seems preferable to use the valsartan + sacubitril (possibly in combination with spironolactone) combination treatment; with phenotype 2, the empagliflozin treatment is the best; with phenotype 3, the phosphodiesterase type 5 inhibitor sildenafil; and with phenotype 4, transthyretin stabilizers. Certain features of different phenotypes overlap and may change as the disease progresses. Nevertheless, the isolation of these phenotypes is advisable to prioritize the choice of drug therapy. Thus, the diuretic treatment (preferably torasemide) should be considered in the presence of congestion, regardless of the HFpEF phenotype; the valsartan + sacubitril and spironolactone treatment is appropriate not only in the shortage of brain natriuretic peptide but also in the presence of concentric left ventricular hypertrophy (except for the amyloidosis phenotype); and the treatment with empagliflozin and statins may be considered in all situations where pro-inflammatory mechanisms are involved.

Current Understanding of Molecular Pathophysiology of Heart Failure With Preserved Ejection Fraction

Heart Failure (HF) is the most common cause of hospitalization in the Western societies. HF is a heterogeneous and complex syndrome that may result from any dysfunction of systolic or diastolic capacity. Abnormal diastolic left ventricular function with impaired relaxation and increased diastolic stiffness is characteristic of heart failure with preserved ejection fraction (HFpEF). HFpEF accounts for more than 50% of all cases of HF. The prevalence increases with age: from around 1% for those aged <55 years to >10% in those aged 70 years or over. Nearly 50% of HF patients have HFrEF and the other 50% have HFpEF/HFmrEF, mainly based on studies in hospitalized patients. The ESC Long-Term Registry, in the outpatient setting, reports that 60% have HFrEF, 24% have HFmrEF, and 16% have HFpEF. To some extent, more than 50% of HF patients are female. HFpEF is closely associated with co-morbidities, age, and gender. Epidemiological evidence suggests that HFpEF is highly represented in older obese women and proposed as 'obese female HFpEF phenotype'. While HFrEF phenotype is more a male phenotype. In addition, metabolic abnormalities and hemodynamic perturbations in obese HFpEF patients appear to have a greater impact in women then in men (Sorimachi et al., European J of Heart Fail, 2022, 22). To date, numerous clinical trials of HFpEF treatments have produced disappointing results. This outcome suggests that a "one size fits all" approach to HFpEF may be inappropriate and supports the use of tailored, personalized therapeutic strategies with specific treatments for distinct HFpEF phenotypes. The most important mediators of diastolic stiffness are the cardiomyocytes, endothelial cells, and extracellular matrix (ECM). The complex physiological signal transduction networks that respond to the dual challenges of inflammatory and oxidative stress are major factors that promote the development of HFpEF pathologies. These signalling networks contribute to the development of the diseases. Inhibition and/or attenuation of these signalling networks also delays the onset of disease. In this review, we discuss the molecular mechanisms associated with the physiological responses to inflammation and oxidative stress and emphasize the nature of the contribution of most important cells to the development of HFpEF via increased inflammation and oxidative stress.

Biomarkers in Heart Failure with Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous disorder developing from multiple aetiologies with overlapping pathophysiological mechanisms. HFpEF diagnosis may be challenging, as neither cardiac imaging nor physical examination are sensitive in this situation. Here, we review biomarkers of HFpEF, of which the best supported are related to myocardial stretch and injury, including natriuretic peptides and cardiac troponins. An overview of biomarkers of inflammation, extracellular matrix derangements and fibrosis, senescence, vascular dysfunction, anaemia/iron deficiency and obesity is also provided. Finally, novel biomarkers from -omics technologies, including plasma metabolites and circulating microRNAs, are outlined briefly. A cardiac-centred approach to HFpEF diagnosis using natriuretic peptides seems reasonable at present in clinical practice. A holistic approach including biomarkers that provide information on the non-cardiac components of the HFpEF syndrome may enrich our understanding of the disease and may be useful in classifying HFpEF phenotypes or endotypes that may guide patient selection in HFpEF trials.

The association between markers of type I collagen synthesis and echocardiographic response to spironolactone in patients at risk of heart failure: findings from the HOMAGE trial

BACKGROUND

Procollagen type I C-terminal propeptide (PICP) and procollagen type III N-terminal propeptide (PIIINP) are markers reflecting collagen synthesis in cardiac fibrosis. However, they may be influenced by the presence of noncardiac comorbidities (e.g., ageing, obesity, renal impairment). Understanding the associations between markers of collagen synthesis and abnormalities of cardiac structure and function is important to screen for myocardial fibrosis and monitor the antifibrotic effect of medications.

METHODS

The HOMAGE (Heart OMics in Aging) trial showed that spironolactone decreased serum PICP concentrations and improved cardiac remodeling over 9 months in a population at risk of developing heart failure (HF). We evaluated the associations between echocardiographic variables, PICP, PIIINP and galectin-3 at baseline and during the course of the trial.

RESULTS

Among 527 individuals (74±7years, 26% women), median serum concentrations of PICP, PIIINP and galectin-3 were 80.6μg/L (65.1-97.0), 3.9μg/L (3.1-5.0) and 16.1μg/L (13.5-19.7), respectively. After adjustment for potential confounders, higher serum PICP was significantly associated with left ventricular hypertrophy, left atrial enlargement, and greater ventricular stiffness (all p-values<0.05), whereas serum PIIINP and galectin-3 were not (all p-values>0.05). In patients treated with spironolactone, a reduction in serum PICP during the trial was associated with a decrease in E/e' (adjusted-beta [95% CI] =0.93 [0.14-1.73]; p=0.022).

CONCLUSIONS

In individuals at high risk of developing HF, serum PICP was associated with cardiac structural and functional abnormalities, and a decrease in PICP with spironolactone was correlated with improved diastolic dysfunction as assessed by E/e'. In contrast, no such associations were present for serum PIIINP and galectin-3.

Cardiac remodelling - Part 1: From cells and tissues to circulating biomarkers. A review from the Study Group on Biomarkers of the Heart Failure Association of the European Society of Cardiology

Cardiac remodelling refers to changes in left ventricular structure and function over time, with a progressive deterioration that may lead to heart failure (HF) development (adverse remodelling) or vice versa a recovery (reverse remodelling) in response to HF treatment. Adverse remodelling predicts a worse outcome, whilst reverse remodelling predicts a better prognosis. The geometry, systolic and diastolic function and electric activity of the left ventricle are affected, as well as the left atrium and on the long term even right heart chambers. At a cellular and molecular level, remodelling involves all components of cardiac tissue: cardiomyocytes, fibroblasts, endothelial cells and leucocytes. The molecular, cellular and histological signatures of remodelling may differ according to the cause and severity of cardiac damage, and clearly to the global trend toward worsening or recovery. These processes cannot be routinely evaluated through endomyocardial biopsies, but may be reflected by circulating levels of several biomarkers. Different classes of biomarkers (e.g. proteins, non-coding RNAs, metabolites and/or epigenetic modifications) and several biomarkers of each class might inform on some aspects on HF development, progression and long-term outcomes, but most have failed to enter clinical practice. This may be due to the biological complexity of remodelling, so that no single biomarker could provide great insight on remodelling when assessed alone. Another possible reason is a still incomplete understanding of the role of biomarkers in the pathophysiology of cardiac remodelling. Such role will be investigated in the first part of this review paper on biomarkers of cardiac remodelling.

Prognosis and diastolic dysfunction predictors in patients with heart failure and recovered ejection fraction

There is limited data on whether diastolic dysfunction in patients with heart failure (HF) and recovered ejection fraction (HFrecEF) is associated with worse prognosis. We retrospectively assessed 96 patients diagnosed with HFrecEF and created ROC curve of their diastolic function at the 1-year follow-up for the composite endpoint of cardiovascular death and HF readmission after the follow-up. Eligible patients were divided into two groups according to the cutoff value of E/e′ ratio (12.1) with the highest AUC (0.70). Kaplan–Meier analysis showed that HFrecEF with high E/e′ group had a significantly poorer prognosis than the low E/e′ group (log-rank, p = 0.01). Multivariate Cox regression analysis revealed that the high E/e′ group was significantly related to the composite endpoint (hazard ratio 5.45, 95% confidence interval [CI] 1.23–24.1). The independent predictors at discharge for high E/e′ ratio at the 1-year follow-up were older age and female sex after adjustment for covariates (odds ratio [OR] 1.07, 95% CI 1.01–1.13 and OR 4.70, 95% CI 1.08–20.5). In conclusion, HFrecEF with high E/e′ ratio might be associated with a poor prognosis. Older age and female sex were independent predictors for a sustained high E/e′ ratio in patients with HFrecEF.

Fibrotic Signaling in Cardiac Fibroblasts and Vascular Smooth Muscle Cells: The Dual Roles of Fibrosis in HFpEF and CAD

Patients with heart failure with preserved ejection fraction (HFpEF) and atherosclerosis-driven coronary artery disease (CAD) will have ongoing fibrotic remodeling both in the myocardium and in atherosclerotic plaques. However, the functional consequences of fibrosis differ for each location. Thus, cardiac fibrosis leads to myocardial stiffening, thereby compromising cardiac function, while fibrotic remodeling stabilizes the atherosclerotic plaque, thereby reducing the risk of plaque rupture. Although there are currently no drugs targeting cardiac fibrosis, it is a field under intense investigation, and future drugs must take these considerations into account. To explore similarities and differences of fibrotic remodeling at these two locations of the heart, we review the signaling pathways that are activated in the main extracellular matrix (ECM)-producing cells, namely human cardiac fibroblasts (CFs) and vascular smooth muscle cells (VSMCs). Although these signaling pathways are highly overlapping and context-dependent, effects on ECM remodeling mainly act through two core signaling cascades: TGF-β and Angiotensin II. We complete this by summarizing the knowledge gained from clinical trials targeting these two central fibrotic pathways.

Therapeutic Approaches in Heart Failure with Preserved Ejection Fraction (HFpEF) in Children: Present and Future

For a long time, pediatric heart failure (HF) with preserved systolic function (HFpEF) has been noted in patients with cardiomyopathies and congenital heart disease. HFpEF is infrequently reported in children and instead of using the  HFpEF terminology the HF symptoms are attributed to diastolic dysfunction. Identifying HFpEF in children is challenging because of heterogeneous etiologies and unknown pathophysiological mechanisms. Advances in echocardiography and cardiac magnetic resonance imaging techniques have further increased our understanding of HFpEF in children. However, the literature does not describe the incidence, etiology, clinical features, and treatment of HFpEF in children. At present, treatment of HFpEF in children is extrapolated from clinical trials in adults. There are significant differences between pediatric and adult HF with reduced ejection fraction, supported by a lack of adequate response to adult HF therapies. Evidence-based clinical trials in children are still not available because of the difficulty of conducting trials with a limited number of pediatric patients with HF. The treatment of HFpEF in children is based upon the clinician's experience, and the majority of children receive off-level medications. There are significant differences between pediatric and adult HFpEF pharmacotherapies in many areas, including side-effect profiles, underlying pathophysiologies, the β-receptor physiology, and pharmacokinetics and pharmacodynamics. This review describes the present and future treatments for children with HFpEF compared with adults. This review also highlights the need to urgently test new therapies in children with HFpEF to demonstrate the safety and efficacy of drugs and devices with proven benefits in adults.