Cardiac inflammation contributes to changes in the extracellular matrix in patients with heart failure and normal ejection fraction

SERCA2a dysfunction in the pathophysiology of heart failure with preserved ejection fraction: a direct role is yet to be established

With rising incidence, mortality and limited therapeutic options, heart failure with preserved ejection fraction (HFpEF) remains one of the most important topics in cardiovascular medicine today. Characterised by left ventricular diastolic dysfunction partially due to impaired Ca2+ homeostasis, one ion channel in particular, SarcoEndoplasmic Reticulum Ca2+-ATPase (SERCA2a), may play a significant role in its pathophysiology. A better understanding of the complex mechanisms interplaying to contribute to SERCA2a dysfunction will help develop treatments targeting it and thus address the growing clinical challenge HFpEF poses. This review examines the conflicting evidence present for changes in SERCA2a expression and activity in HFpEF, explores potential underlying mechanisms, and finally evaluates the drug and gene therapy trials targeting SERCA2a in heart failure. Recent positive results from trials involving widely used anti-diabetic agents such as sodium-glucose co-transporter protein 2 inhibitors (SGLT2i) and glucagon-like peptide-1 (GLP-1) agonists offer advancement in HFpEF management. The potential interplay between these agents and SERCA2a regulation presents a novel angle that could open new avenues for modulating diastolic function; however, the mechanistic research in this emerging field is limited. Overall, the direct role of SERCA2a dysfunction in HFpEF remains undetermined, highlighting the need for well-designed pre-clinical studies and robust clinical trials.

Focusing on microvascular function in heart failure with preserved ejection fraction

Heart failure is a prevalent global health issue. Heart failure with preserved ejection fraction (HFpEF), which already represents half of all heart cases worldwide, is projected to further increase, driven by aging populations and rising cardiovascular risk factors. Effective therapies for HFpEF remain limited, particularly due to its pathophysiological heterogeneity and incomplete understanding of underlying pathomechanisms and implications. Coronary microvascular dysfunction (CMD), characterized by structural and functional changes in the coronary microcirculation, is increasingly recognized as a significant factor in HFpEF even though the exact nature of their causal relationship is still unclear. This review explores prevalence, prognostic implications, and potential therapeutic targets for CMD in HFpEF. CMD's role in HFpEF might involve impaired coronary blood flow regulation, leading to myocardial ischemia, impaired relaxation, and/or adverse remodeling. Vice versa, increased wall stress in patients with HFpEF might elevate coronary resistances, further worsening microvascular perfusion. Finally, abnormalities in substrate metabolism might cause both CMD and HFpEF. Current treatments, including pharmacotherapy and device-based therapies, show limited success, highlighting the need for more targeted approaches. New possible therapies, such as the coronary sinus reducer device, may show promise in improving myocardial perfusion and function. However, further large-scale studies are required to elucidate the mechanistic links between CMD and HFpEF and to develop specialized treatments for distinct heart failure phenotypes.

Cardiometabolic Phenotype in HFpEF: Insights from Murine Models

Heart failure with preserved ejection fraction (HFpEF) remains a significant challenge in modern healthcare. It accounts for the majority of heart failure cases and their number worldwide is steadily increasing. With its high prevalence and substantial clinical impact, therapeutic strategies for HFpEF are still inadequate. This review focuses on the cardiometabolic phenotype of HFpEF which is characterised by such conditions as obesity, type 2 diabetes mellitus, and hypertension. Various murine models that mimic this phenotype are discussed. Each model's pathophysiological aspects, namely inflammation, oxidative stress, endothelial dysfunction, changes in cardiomyocyte protein function, and myocardial metabolism alterations are examined in detail. Understanding these models can provide insight into the mechanisms underlying HFpEF and aid in the development of effective therapeutic interventions.

Opportunities and challenges for the use of human samples in translational cardiovascular research: a scientific statement of the ESC Working Group on Cellular Biology of the Heart, the ESC Working Group on Cardiovascular Surgery, the ESC Council on Basic Cardiovascular Science, the ESC Scientists of Tomorrow, the European Association of Percutaneous Cardiovascular Interventions of the ESC, and the Heart Failure Association of the ESC

Animal models offer invaluable insights into disease mechanisms but cannot entirely mimic the variability and heterogeneity of human populations, nor the increasing prevalence of multi-morbidity. Consequently, employing human samples-such as whole blood or fractions, valvular and vascular tissues, myocardium, pericardium, or human-derived cells-is essential for enhancing the translational relevance of cardiovascular research. For instance, myocardial tissue slices, which preserve crucial structural and functional characteristics of the human heart, can be used in vitro to examine drug responses. Human blood serves as a rich source of biomarkers, including extracellular vesicles, various types of RNA (miRNA, lncRNA, and circRNAs), circulating inflammatory cells, and endothelial colony-forming cells, facilitating detailed studies of cardiovascular diseases. Primary cardiomyocytes and vascular cells isolated from human tissues are invaluable for mechanistic investigations in vitro. In cases where these are unavailable, human induced pluripotent stem cells serve as effective substitutes, albeit with specific limitations. However, the use of human samples presents challenges such as ethical approvals, tissue procurement and storage, variability in patient genetics and treatment regimens, and the selection of appropriate control samples. Biobanks are central to the efficient use of these scarce and valuable resources. This scientific statement discusses opportunities to implement the use of human samples for cardiovascular research within specific clinical contexts, offers a practical framework for acquiring and utilizing different human materials, and presents examples of human sample applications for specific cardiovascular diseases, providing a valuable resource for clinicians, translational and basic scientists engaged in cardiovascular research.

The gut microbiota-inflammation-HFpEF axis: deciphering the role of gut microbiota dysregulation in the pathogenesis and management of HFpEF

Heart failure with preserved left ventricular ejection fraction (HFpEF) is a disease that affects multiple organs throughout the body, accounting for over 50% of heart failure cases. HFpEF has a significant impact on individuals' life expectancy and quality of life, but the exact pathogenesis remains unclear. Emerging evidence implicates low-grade systemic inflammation as a crucial role in the onset and progression of HFpEF. Gut microbiota dysregulation and associated metabolites alteration, including short-chain fatty acids, trimethylamine N-oxides, amino acids, and bile acids can exacerbate chronic systemic inflammatory responses and potentially contribute to HFpEF. In light of these findings, we propose the hypothesis of a "gut microbiota-inflammation-HFpEF axis", positing that the interplay within this axis could be a crucial factor in the development and progression of HFpEF. This review focuses on the role of gut microbiota dysregulation-induced inflammation in HFpEF's etiology. It explores the potential mechanisms linking dysregulation of the gut microbiota to cardiac dysfunction and evaluates the therapeutic potential of restoring gut microbiota balance in mitigating HFpEF severity. The objective is to offer novel insights and strategies for the management of HFpEF.

Whole tissue proteomic analyses of cardiac ATTR and AL unveil mechanisms of tissue damage

BACKGROUND

Cardiac AL and ATTR are potentially fatal cardiomyopathies. Current therapies do not address mechanisms of tissue dysfunction because these remain unknown. Our prior work focused on the amyloid plaque proteome, which may not capture tissue-wide proteomic alterations.

OBJECTIVES

To evaluate mechanisms of tissue dysfunction in cardiac AL and ATTR using a full biopsy tissue proteomics approach.

METHODS

We performed proteomics analysis on 76 ATTR and 27 AL diagnostic endomyocardial biopsies.

RESULTS

Stage-3 AL patients exhibited increased coagulation, extracellular matrix remodelling (ECM), epithelial-to-mesenchymal transition (EMT), complement activation, hypoxia, and clathrin-mediated endocytosis pathways vs. stages-1/2, with decreased healthy cardiac metabolism. In stages-2 and 3 ATTR, immunoglobulin proteins, complement, and keratinisation pathways were increased compared to stage-1. Unsupervised analyses identified an ATTR group with worse survival characterised by upregulated complement and downregulated metabolic pathways. Compared to ATTR, AL had higher clathrin-mediated endocytosis, mRNA splicing, and ribosomal proteins, while ATTR had higher complement levels.

CONCLUSIONS

This study identifies known processes dysregulated in heart failure with preserved ejection fraction as well as novel pathways responsible for tissue damage. Our results support an immune-mediated mechanism of tissue toxicity in cardiac amyloidosis, especially among patients with worse outcomes.

Rate Versus Rhythm Control for Atrial Fibrillation with Heart Failure

Atrial fibrillation with Heart Failure is a constellation of co-morbid conditions that now constitutes a major cardiovascular epidemic, with HF now the most common complication of AF. Mechanistically, both conditions promote substrate disease in the atrium and ventricle. AF is an independent rixk factor in HF progression and pump failure death. While early studies comparing rhythm control antiarrhythmic drugs and rate control drugs showed no significant benefit in cardiovascular outcomes, AF did promote HF emergence and hospitalizations. Newer rhythm control strategies with present day antiarrhythmic drugs and catheter ablation support benefits in cardiovascular outcomes in AF with HF. Catheter ablation improved HF outcomes in HF with reduced ejection fraction but further and larger studies are needed, especially for AF with HF with preserved ejection fraction.

Molecular Mechanisms Underlying Heart Failure and Their Therapeutic Potential

Heart failure (HF) is a prominent fatal cardiovascular disorder afflicting 3.4% of the adult population despite the advancement of treatment options. Therefore, a better understanding of the pathogenesis of HF is essential for exploring novel therapeutic strategies. Hypertrophy and fibrosis are significant characteristics of pathological cardiac remodeling, contributing to HF. The mechanisms involved in the development of cardiac remodeling and consequent HF are multifactorial, and in this review, the key underlying mechanisms are discussed. These have been divided into the following categories thusly: (i) mitochondrial dysfunction, including defective dynamics, energy production, and oxidative stress; (ii) cardiac lipotoxicity; (iii) maladaptive endoplasmic reticulum (ER) stress; (iv) impaired autophagy; (v) cardiac inflammatory responses; (vi) programmed cell death, including apoptosis, pyroptosis, and ferroptosis; (vii) endothelial dysfunction; and (viii) defective cardiac contractility. Preclinical data suggest that there is merit in targeting the identified pathways; however, their clinical implications and outcomes regarding treating HF need further investigation in the future. Herein, we introduce the molecular mechanisms pivotal in the onset and progression of HF, as well as compounds targeting the related mechanisms and their therapeutic potential in preventing or rescuing HF. This, therefore, offers an avenue for the design and discovery of novel therapies for the treatment of HF.

Pathophysiological insights into HFpEF from studies of human cardiac tissue

Heart failure with preserved ejection fraction (HFpEF) is a major, worldwide health-care problem. Few therapies for HFpEF exist because the pathophysiology of this condition is poorly defined and, increasingly, postulated to be diverse. Although perturbations in other organs contribute to the clinical profile in HFpEF, altered cardiac structure, function or both are the primary causes of this heart failure syndrome. Therefore, studying myocardial tissue is fundamental to improve pathophysiological insights and therapeutic discovery in HFpEF. Most studies of myocardial changes in HFpEF have relied on cardiac tissue from animal models without (or with limited) confirmatory studies in human cardiac tissue. Animal models of HFpEF have evolved based on theoretical HFpEF aetiologies, but these models might not reflect the complex pathophysiology of human HFpEF. The focus of this Review is the pathophysiological insights gained from studies of human HFpEF myocardium. We outline the rationale for these studies, the challenges and opportunities in obtaining myocardial tissue from patients with HFpEF and relevant comparator groups, the analytical approaches, the pathophysiological insights gained to date and the remaining knowledge gaps. Our objective is to provide a roadmap for future studies of cardiac tissue from diverse cohorts of patients with HFpEF, coupling discovery biology with measures to account for pathophysiological diversity.

The relationship between tissue inhibitor of metalloproteinases-1 and KCNJ5 mutation in aldosterone-producing adenoma patients

KCNJ5 somatic mutations in aldosterone-producing adenoma (APA) are linked to higher left ventricular mass index (LVMI) and worse diastolic function. We previously identified an association between plasma tissue inhibitor of metalloproteinases-1 (TIMP-1) and an aldosterone-induced increase in LVMI and diastolic dysfunction. This study aimed to investigate the association between the presence of KCNJ5 somatic mutation and plasma TIMP-1 in APA patients. We enrolled 60 APA patients undergoing adrenalectomy, including 30 with KCNJ5 mutations (KCNJ5(+)) and 30 without (KCNJ5(-)). Clinical characteristics, echocardiographic data (including LVMI, inappropriately excessive LVMI (ieLVMI), and diastolic function) and plasma TIMP-1 levels were measured before surgery and 1 year postoperatively. The results showed that the KCNJ5(+) group had higher plasma TIMP-1 levels (P = 0.004) compared to the KCNJ5(-) group. The correlation between the KCNJ5 mutations and TIMP-1 levels remained significant after multiple regression analysis. To detect KCNJ5 mutations, receiver operating characteristic curve analysis showed TIMP-1 had the best area under the curve (AUC) value among various clinical parameters (AUC = 0.682, 95% confidence interval = 0.549-0.796, P = 0.008). Post-adrenalectomy, only the KCNJ5(+) group showed significant decrease in LVMI (P = 0.001) and log-transformed TIMP-1 levels (P = 0.035). Changes in ieLVMI before and after surgery were consistently correlated with changes in TIMP-1 levels in multivariable regression analysis. In conclusion, KCNJ5 somatic mutations in APA are associated with higher plasma TIMP-1 levels. In addition, TIMP-1 is an effective biomarker for detecting the presence of KCNJ5 mutations in APA patients.

Efficacy and safety of creatine phosphate sodium in the treatment of viral myocarditis: A systematic review and meta-analysis

PURPOSE

To systematically evaluate the efficacy and safety of creatine phosphate sodium in the treatment of viral myocarditis, and to provide guidance for its clinical treatment.

METHODS

We conducted a search of The Cochrane Library, PubMed, EMbase, and Web of Science databases to retrieve randomized controlled trials (RCTs) on the use of creatine phosphate sodium (CPS) in the treatment of viral myocarditis. The search was conducted up to April 2024. After screening the literature, extracting data, and evaluating the risk of bias in the included studies, we performed a meta-analysis using RevMan 5.4 and Stata17.0 statistical software.

RESULTS

A total of 104 articles were retrieved, and 9 articles with a combined total of 1,116 patients were ultimately included in the meta-analysis. The results of the meta-analysis indicated that the overall efficacy rate in the phosphocreatine sodium treatment group was higher than that in the control group [RR = 1.22, 95%CI (1.15, 1.28), P<0.00001]. Furthermore, post-treatment levels of cardiac troponin I [MD = 0.1, 95%CI (0.07, 0.13), P<0.00001] and creatine kinase isoenzyme [MD = 9.43, 95%CI (7.04,11 .82), P<0 .00001] in the phosphocreatine treatment group were lower compared to those in the control group; both differences between groups were statistically significant. Additionally, there was no significant difference observed in adverse reaction incidence between the phosphocreatine sodium treatment group and conventional treatment group [RR = 1 .07, 95% CI (0 .68, 1 .67), P = O .77].

CONCLUSION

Creatine phosphate sodium treatment can significantly improve the therapeutic effect of patients with viral myocarditis, and can reduce the levels of cTnI and CK-MB. Compared with conventional treatment, it has good safety.

Caloric restriction and its mimetics in heart failure with preserved ejection fraction: mechanisms and therapeutic potential

The global increase in human life expectancy, coupled with an unprecedented rise in the prevalence of obesity, has led to a growing clinical and socioeconomic burden of heart failure with preserved ejection fraction (HFpEF). Mechanistically, the molecular and cellular hallmarks of aging are omnipresent in HFpEF and are further exacerbated by obesity and associated metabolic diseases. Conversely, weight loss strategies, particularly caloric restriction, have shown promise in improving health status in patients with HFpEF and are considered the gold standard for promoting longevity and healthspan (disease-free lifetime) in model organisms. In this review, we implicate fundamental mechanisms of aging in driving HFpEF and elucidate how caloric restriction mitigates the disease progression. Furthermore, we discuss the potential for pharmacologically mimicking the beneficial effects of caloric restriction in HFpEF using clinically approved and emerging caloric restriction mimetics. We surmise that these compounds could offer novel therapeutic avenues for HFpEF and alleviate the challenges associated with the implementation of caloric restriction and other lifestyle modifications to reduce the burden of HFpEF at a population level.

Coronary Microvascular Dysfunction: Insights on Prognosis and Future Perspectives

Coronary microvascular dysfunction (CMD) comprises a wide spectrum of structural and/or functional abnormalities of coronary microcirculation that can lead to myocardial ischemia. Emerging evidence has indicated that CMD is a relevant cause of morbidity and mortality and is associated with a high risk of major adverse cardiovascular events (MACEs) and heart failure with preserved ejection fraction as well as poor quality of life. This review aims to elucidate briefly the pathogenesis and diagnostic modalities of CMD and to shed light on contemporary evidence on the prognostic impact of CMD. Finally, we will provide an overview of novel emerging therapeutic strategies for CMD.

GLP-1 receptor agonists as promising anti-inflammatory agents in heart failure with preserved ejection fraction

Heart Failure with Preserved Ejection Fraction (HFpEF) represents a significant challenge in modern cardiovascular medicine, characterized by diastolic dysfunction and a chronic pro-inflammatory milieu. The high prevalence of comorbidities such as diabetes, visceral obesity, and aging, which contribute to systemic inflammation, plays a pivotal role in the pathogenesis and progression of HFpEF. Glucagon-Like Peptide-1 Receptor Agonists (GLP-1 RAs), a class of glucose-lowering drugs, have demonstrated a wide range of pleiotropic effects that extend beyond glycaemic control. These effects include the reduction of inflammation and oxidative stress, vasodilation, decreased arterial stiffness, and a reduction in myocardial fibrosis-key factors in the pathophysiology of HFpEF. Recent evidence from the STEP-HFpEF and STEP-HFpEF-DM trials provides the first robust data supporting the efficacy of GLP-1 RAs, specifically semaglutide, in improving the quality of life in obese patients with HFpEF. These trials also demonstrated a significant reduction in C-Reactive Protein (CRP) levels, reinforcing the hypothesis that suppressing the pro-inflammatory state may yield substantial clinical benefits in this patient population. These findings suggest that GLP-1 RAs could play a crucial role in the management of HFpEF, particularly in patients with obesity, by targeting the underlying inflammatory processes and contributing to better overall cardiovascular outcomes.

Inadequate identification of high cardiovascular risk and carotid plaques in rheumatoid arthritis patients by the 2024 Predicting Risk of Cardiovascular EVENTs and the 2013 Atherosclerotic Cardiovascular Disease algorithms: findings from a Mexican cohort

The American College of Cardiology/American Heart Association introduced the Predicting Risk of Cardiovascular EVENTs (PREVENT™) algorithm to estimate the 10-year risk of developing cardiovascular disease. We aimed to assess the cardiovascular risk (CVR) reclassification among rheumatoid arthritis (RA) patients using traditional CVR algorithms-the 2024 PREVENT™ and the 2013 Atherosclerotic Cardiovascular Disease (ASCVD)-and the presence of carotid plaque (CP). This was a cross-sectional study nested of a RA patients' cohort. A certified radiologist performed a high-resolution B-mode carotid ultrasound to identify the presence of CP. The CVR evaluation was performed by a cardiologist, blinded to carotid ultrasound results, using the PREVENT™ and the ASCVD algorithms. Cohen's kappa (k) coefficient assessed concordance between high-risk classification by CVR algorithms and CP presence. ROC curve analysis evaluated the algorithms' capacity to identify RA patients with CP. The cutoff point was determined by the Youden-Index, with p < 0.05 as statistically significant. A total of 210 RA patients were included. The reclassification of CVR due to CP was 34.3% for the PREVENT™ algorithm and 30.0% for the ASCVD algorithm. Of these, 44.4% and 71.4%, respectively, were initially classified as low risk. Concordance between CVR algorithms and carotid ultrasound showed slight agreement (k = 0.032 and k = 0.130, respectively). The PREVENT™ algorithm did not identify more than one-third of high-CVR RA patients with indication of starting statin therapy based on carotid ultrasound findings. The PREVENT™ and ASCVD algorithms showed poor performance in identifying RA patients with CP. Key Points • The presence of CP was identified in more than a third of the evaluated RA patients (35.7%), classifying them as high CVR. • CVR reclassification by the presence of CP was observed in 34.3% RA patients with the PREVENTTM algorithm and in 30.0% RA patients with the ASCVD algorithm. • Most of the reclassified patients belonged to the low-risk category, 44.4% with the PREVENTTM algorithm and 71.4% with the ASCVD algorithm. • When evaluating the concordance between the ASCVD algorithm and the carotid ultrasound for high-risk classification, a slight agreement was found (k = 0.130).

Novel Therapeutic Strategies Targeting Fibroblasts to Improve Heart Disease

Cardiac fibrosis represents the terminal pathological manifestation of various heart diseases, with the formation of fibroblasts playing a pivotal role in this process. Consequently, targeting the formation and function of fibroblasts holds significant potential for improving outcomes in heart disease. Recent research reveals the considerable potential of fibroblasts in ameliorating cardiac conditions, demonstrating different functional characteristics at various time points and spatial locations. Therefore, precise modulation of fibroblast activity may offer an effective approach for treating cardiac fibrosis and achieving targeted therapeutic outcomes. In this review, we focus on the fate and inhibition of fibroblasts, analyze their dynamic changes in cardiac diseases, and propose a framework for identifying markers of fibroblast activation mechanisms and selecting optimal time windows for therapeutic intervention. By synthesizing research findings in these areas, we aim to provide new strategies and directions for the precise treatment of fibroblasts in cardiac diseases.

Heart Failure in Rheumatoid Arthritis: Clinical Implications

PURPOSE OF REVIEW

This review focuses on the association between RA and heart failure, highlighting the role of inflammation and the prevalence of heart failure with preserved ejection fraction (HFpEF) in this population.

RECENT FINDINGS

The incidence of heart failure in RA patients is two to three times higher than in the general population, with inflammation playing a significant role independent of traditional cardiovascular risk factors. HFpEF accounts for about half of heart failure cases and is increasingly recognized in RA patients, although it remains underdiagnosed. Atypical presentations and non-specific symptoms further complicate diagnosis. Early control of inflammation has been shown to reduce the risk of heart failure development and progression, improving both morbidity and mortality outcomes. Rheumatoid arthritis (RA) is a systemic inflammatory disease affecting approximately 1% of the population, with cardiovascular disease being the leading cause of premature death in these patients.

Beyond Encapsulation: Exploring Macrophage-Fibroblast Cross Talk in Implant-Induced Fibrosis

The foreign body response (FBR) and organ fibrosis are complex biological processes involving the interaction between macrophages and fibroblasts. Understanding the molecular mechanisms underlying macrophage-fibroblast cross talk is crucial for developing strategies to mitigate implant encapsulation, a major cause of implant failure. This article reviews the current knowledge on the role of macrophages and fibroblasts in the FBR and organ fibrosis, highlighting the similarities between these processes. The FBR is characterized by the formation of a fibrotic tissue capsule around the implant, leading to functional impairment. Various factors, including material properties such as surface chemistry, stiffness, and topography, influence the degree of encapsulation. Cross talk between macrophages and fibroblasts plays a critical role in both the FBR and organ fibrosis. However, the precise molecular mechanisms remain poorly understood. Macrophages secrete a wide range of cytokines that modulate fibroblast behavior such as abundant collagen deposition and myofibroblast differentiation. However, the heterogeneity of macrophages and fibroblasts and their dynamic behavior in different tissue environments add complexity to this cross talk. Experimental evidence from in vitro studies demonstrates the impact of material properties on macrophage cytokine secretion and fibroblast physiology. However, the correlation between in vitro response and in vivo encapsulation outcomes is not robust. Adverse outcome pathways (AOPs) offer a potential framework to understand and predict process complexity. AOPs describe causal relationships between measurable events leading to adverse outcomes, providing mechanistic insights for in vitro testing and predictive modeling. However, the development of an AOP for the FBR does require a comprehensive understanding of the molecular initiating events and key event relationships to identify which events are essential. In this article, we describe the current knowledge on macrophage-fibroblast cross talk in the FBR and discuss how targeted research can help build an AOP for implant-related fibrosis. Impact statement Biomaterials are widely used to manufacture medical devices, but implantation is associated with a foreign body response (FBR), which may lead to failure of the implants. Surface properties are related to FBR severity. In this review, we zoom in on the cross talk between the two key players, macrophages and fibroblasts, and propose the use of Adverse Outcome Pathways to decipher the causal link between material properties and the severity of the FBR. This approach will help increase a mechanistic understanding of the FBR and, thus, aid in the design of immunomodulatory implant surfaces.

Prevalence, Incidence, and Outcomes of Diastolic Dysfunction in Isolated Tricuspid Regurgitation: Perhaps Not Really "Isolated"?

BACKGROUND

In the absence of left-sided cardiac/pulmonary disease, functional tricuspid regurgitation (FTR) is referred to as isolated or idiopathic. Relationships between left ventricular diastolic dysfunction (DD) and FTR remain unknown.

OBJECTIVES

The purpose of this study was to investigate the prevalence, incidence, and outcome of DD in patients with idiopathic FTR.

METHODS

Adults without structural heart disease were identified. Severe DD was defined by ≥3 of 4 abnormal DD parameters (medial e', medial E/e', TR velocity, left atrial volume index) and ≥ moderate DD by ≥2. Propensity-score matching was performed (3:1) between each less-than-severe TR group and severe TR based on age, sex, body mass index, and comorbidities.

RESULTS

Among 30,428 patients, FTR was absent in 73%, mild in 22%, moderate in 4%, and severe in 0.4%. In the propensity-matched sample, severe DD was present in 2%, 6%, 9%, and 13% patients, and ≥ moderate DD in 11%, 18%, 28%, and 48%, respectively (P < 0.001). The probability of heart failure with preserved ejection fraction using the H2FPEF score increased with increasing FTR (median 29.7%, 45.5%, 61.4%, and 88.7%, respectively), as did the prevalence of impaired left atrial strain <24% (35%, 48%, and 69% in mild, moderate, and severe TR). Incident severe and ≥ moderate DD developed more frequently with increasing FTR (HR: 8.45 [95% CI: 2.60-27.50] and HR: 2.82 [95% CI: 1.40-5.69], respectively for ≥ moderate vs no FTR) over a median of 3.0 years. Findings were confirmed in patients without lung disease or right ventricular enlargement. Over a median of 5.0 years, patients with ≥ moderate FTR and DD had the greatest risk of worse outcomes (multivariable P < 0.001). The association between TR and adverse outcomes was significantly diminished in the absence of DD.

CONCLUSIONS

Diastolic dysfunction, increased heart failure with preserved ejection fraction probability, and impaired left atrial strain are commonly present in patients with idiopathic FTR, suggesting that the latter may not be truly isolated. Patients with FTR without DD or heart failure are at increased risk of incident DD. Patients with FTR and DD display worse outcomes.

Astragaloside IV alleviates inflammation and improves myocardial metabolism in heart failure mice with preserved ejection fraction

Background

Heart failure with preserved ejection fraction (HFpEF) has grown to become the dominant form of heart failure worldwide. However, no unequivocally effective treatment for HFpEF has been identified in clinical trials. In this study, we report that Astragaloside IV (AS-IV) can be used to treat HFpEF.

Methods

Mice were fed on a high-fat diet and given 0.5 g/L L-NAME (in drinking water) for 10 weeks to establish the HFpEF model. After 10th weeks, the HFpEF mice were given 10 mg/kg empagliflozin, 10 mg/kg AS-IV, or 20 mg/kg AS-IV for 4 weeks. The echocardiography, blood pressure, hemodynamics, heart failure biomarkers, collagen deposition and fibrosis, histopathology, and inflammation in HFpEF mice were evaluated. Metabolic profiling based on NMR measurements was also performed. Myocardial glucose and fatty acid metabolism were evaluated.

Results

AS-IV improves cardiac function and myocardial remodeling in HFpEF mice. AS-IV attenuates systemic inflammatory infiltration and myocardial inflammation levels in HFpEF mice by decreasing the expression of plasma inflammatory markers GDF15, CRP, IL1RL1, and MCP-1, NLRP3, IL-1β, Caspase-1, and IL-6 in the myocardium of HFpEF mice. Metabolomic analysis suggested that AS-IV improved cardiac glucose and fatty acid metabolism in HFpEF mice. Further studies showed that AS-IV significantly improved Complex I activity, increased ATP production, and elevated plasma NAD + levels; AS-IV also significantly improved pyruvate dehydrogenase activity and decreased pyruvate and lactate accumulation, thereby improving glucose metabolism in the hearts of HFpEF mice.

Conclusion

These results provide novel evidence that Astragaloside IV alleviates inflammation and improves myocardial metabolism in HFpEF mice.

The Macrophage-Fibroblast Dipole in the Context of Cardiac Repair and Fibrosis

Stromal and immune cells and their interactions have gained the attention of cardiology researchers and clinicians in recent years as their contribution in cardiac repair is increasingly recognized. The repair process in the heart is a particularly critical constellation of complex molecular and cellular events and interactions that characteristically fail to ensure adequate recovery following injury, insult, or exposure to stress conditions in this regeneration-hostile organ. The tremendous consequence of this pronounced inability to maintain homeostatic states is being translated in numerous ways promoting progress into heart failure, a deadly, irreversible condition requiring organ transplantation. Fibrosis is in fact a repair response eventually promoting cardiac dysfunction and cardiac fibroblasts are the major cellular players in this process, overproducing collagens and other extracellular matrix components when activated. On the other hand, macrophages may differentially affect fibroblasts and cardiac repair depending on their status and subsets. The opposite interaction is also probable. We discuss here the multifaceted aspects and crosstalk of this cell dipole and the opportunities it may offer for beneficial manipulation approaches that will hopefully lead to progress in heart disease interventions.

Effects of Sacubitril/Valsartan on cardiac function, blood biochemistry and clinical efficacy in early ventricular remodeling after acute myocardial infarction

Ventricular remodeling (VR) after acute ST-elevation myocardial infarction (STEMI) is an important predictor for medium- and long-term prognosis. This study focuses on the relevant indexes of VR in patients with AMI, in which, the intervention effects of sacubitril/valsartan and enalapril were compared, guiding the clinical treatment. 58 patients with acute STEMI treated with PCI were divided into research group and control group. UCG was performed at 1 week, 1 month and 3 months after MI, and the patients' indexes were collected to compare VR and adverse reactions in the two groups. The test results showed that there was no statistical difference in the baseline data of patients in the two groups, which were comparable. In the blood biochemical index examination, no statistical difference was found in cTnI and NT-proBNP between the two groups. At 1 week after operation, the levels of cTnI and NT-proBNP in research group were lower than those in the control group. In ECG examination, there was no statistical significance in the levels of LVEF, LVEDD and LVESD at admission between the two groups. After 1 week, the results of LVEF, LVEDD, LVESD in the research group were higher than those in the control group. The results of this study show that sacubitril/valsartan can be used in patients with AMI instead of enalapril. Sacubitril/valsartan improves cardiac function in patients with emergency percutaneous coronary intervention (PCI) for AMI, inhibits ventricular remodeling, and has a low incidence of adverse cardiac events and adverse drug reactions.

Investigation of the efficacy of Dengzhan Shengmai capsule against heart failure with preserved ejection fraction

ETHNOPHARMACOLOGICAL RELEVANCE

Heart failure with preserved ejection fraction (HFpEF) has emerged as a condition with high incidence and mortality rates in recent years. Dengzhan Shengmai capsule (DZSMC) is a Chinese patent medicine based on the classic recipe "Shengmai powder". The relevant Chinese medicine ratio of Erigeron breviscapus (Vaniot) Hand.-Mazz., Panax ginseng C.A.Mey., Schisandra chinensis (Turcz.) Baill., and Ophiopogon japonicus (Thunb.) Ker Gawl. Is 30 : 6: 6 : 11. Traditional Chinese medicine (TCM) is being increasingly explored as a safe and effective treatment modality for HFpEF. Clinical studies have shown that DZSMCs can effectively treat heart failure, however, the mechanism of action of DZSMCs in the treatment of HFpEF are still not clear.

AIM OF THE STUDY

To investigate the efficacy and underlying mechanisms of Dengzhan Shengmai capsule (DZSMC), in the treatment of HFpEF by focusing on its ability to treat microvascular inflammation.

MATERIALS AND METHODS

First, the efficacy of DZSMCs against HFpEF was predicted by network pharmacology. After 3 days of adaptive feeding in SPF-grade polypropylene cages, the mice in the Model group, DZSMC group, and Captopli group underwent single kidney resection, and micropumps were implanted in their backs for continuous infusion of aldosterone at a rate of 0.3 μg/h for 4 weeks. Moreover, the mice were given DZSMCs or Captopli via oral gavage for four weeks. Overall, cardiac function was evaluated in mice, and cardiac ultrasound and blood biochemical indices were evaluated in HFpEF mice.

RESULTS

DZSMCs can ameliorate myocardial hypertrophy and cardiomyocyte damage caused by excessive myocardial stress, ultimately mitigating long-term cardiac impairment; it aids in the restoration of myocardial fibre proliferation and enhances mitochondrial morphology and function. In a murine model of ventricular hypertrophy and left ventricular dysfunction, which are indicative of cardiac insufficiency, the administration of DZSMCs resulted in notable improvements. Echocardiographic and overall assessments of cardiac function revealed a reduction in cardiac dysfunction and ventricular hypertrophy post-DZSMC intervention. Moreover, intervention with DZSMCs led to a reduction in the serum levels of several markers associated with chronic systemic inflammation, such as sST2, IL1RL1, CRP, and IL-6. Simultaneously, the levels of indicators of microvascular inflammation, including VCAM and E-SELECTIN, also decreased following DZSMC intervention. These findings suggest the potential multifaceted impact of DZSMCs in alleviating cardiac abnormalities, mitigating systemic inflammation, and reducing microvascular inflammatory markers, highlighting their promising therapeutic role in managing myocardial health.

CONCLUSIONS

These results provide novel evidence that DZSMCs improve HFpEF by regulating microvascular inflammation.

Myocardial inflammatory cells in cardiac amyloidosis

BACKGROUND

Immunoglobulin derived AL amyloidosis and transthyretin derived ATTR amyloidosis are the most common forms of cardiac amyloidosis. Both may present with cardiac arrhythmias, heart failure, and extracardiac symptoms. Disease outcome is often fatal. Recently, it was proposed that amyloid may cause cardiac inflammation. Here we tested the hypothesis that immune cell infiltration in cardiac tissue correlates with clinicopathological patient characteristics.

PATIENTS AND METHODS

Myocardial biopsies from 157 patients with cardiac amyloidosis (46.5% AL, 53.3% ATTR) were immunohistochemically assessed for the presence and amount of T lymphocytes (CD3), macrophages (CD68) and neutrophils (MPO). Amyloid load, cardiomyocyte diameter, apoptosis (Caspase 3), necrosis (complement 9), and various clinical parameters were assessed and correlated with immune cell density.

RESULTS

Myocardial tissue was infiltrated with T lymphocytes (CD3), macrophages (CD68) and neutrophils (MPO) with variable amounts. Significant correlations were found between the number of macrophages and NYHA class. No correlations were found between the presence and amount of T lymphocytes, neutrophils and clinicopathological patient characteristics.

CONCLUSION

The significant correlation between cardiac macrophage density and heart failure points towards a significant role of macrophages in disease pathology.

Heart failure with preserved ejection fraction: The role of inflammation

Heart failure (HF) is a debilitating clinical syndrome affecting 64.3 million patients worldwide. More than 50% of HF cases are attributed to HF with preserved ejection fraction (HFpEF), an entity growing in prevalence and mortality. Although recent breakthroughs reveal the prognostic benefits of sodium-glucose co-transporter 2 inhibitors (SGLT2i) in HFpEF, there is still a lack of effective pharmacological therapy available. This highlights a major gap in medical knowledge that must be addressed. Current evidence attributes HFpEF pathogenesis to an interplay between cardiometabolic comorbidities, inflammation, and renin-angiotensin-aldosterone-system (RAAS) activation, leading to cardiac remodelling and diastolic dysfunction. However, conventional RAAS blockade has demonstrated limited benefits in HFpEF, which emphasises that alternative therapeutic targets should be explored. Presently, there is limited literature examining the use of anti-inflammatory HFpEF therapies despite growing evidence supporting its importance in disease progression. Hence, this review aims to explore current perspectives on HFpEF pathogenesis, including the importance of inflammation-driven cardiac remodelling and the therapeutic potential of anti-inflammatory therapies.

The Emerging Role of Glucagon-like Peptide-1 Receptor Agonists in the Management of Obesity-Related Heart Failure with Preserved Ejection Fraction: Benefits beyond What Scales Can Measure?

Obesity is a significant predisposing factor for heart failure with preserved ejection fraction (HFpEF). Although a substantial proportion of individuals with HFpEF also have obesity, those with obesity are under-represented in clinical trials for heart failure. In turn, current guidelines provided limited recommendations for the medical management of this patient population. Both obesity and diabetes induce a pro-inflammatory state that can contribute to endothelial dysfunction and coronary microvascular impairment, finally resulting in HFpEF. Additionally, obesity leads to increased epicardial and chest wall adiposity, which enhances ventricular interdependence. This condition is further aggravated by plasma and blood volume expansion and excessive vasoconstriction, ultimately worsening HFpEF. Despite the well-documented benefits of GLP-1 receptor agonists in subjects with diabetes, obesity, or both, their role in obesity-related HFpEF remains unclear. In light of the recently published literature, this review aims to investigate the potential mechanisms and synthesize the available clinical evidence regarding the role of GLP-1 receptor agonists in patients with obesity-related HFpEF.

Protein kinase N promotes cardiac fibrosis in heart failure by fibroblast-to-myofibroblast conversion

Chronic fibrotic tissue disrupts various organ functions. Despite significant advances in therapies, mortality and morbidity due to heart failure remain high, resulting in poor quality of life. Beyond the cardiomyocyte-centric view of heart failure, it is now accepted that alterations in the interstitial extracellular matrix (ECM) also play a major role in the development of heart failure. Here, we show that protein kinase N (PKN) is expressed in cardiac fibroblasts. Furthermore, PKN mediates the conversion of fibroblasts into myofibroblasts, which plays a central role in secreting large amounts of ECM proteins via p38 phosphorylation signaling. Fibroblast-specific deletion of PKN led to a reduction of myocardial fibrotic changes and cardiac dysfunction in mice models of ischemia-reperfusion or heart failure with preserved ejection fraction. Our results indicate that PKN is a therapeutic target for cardiac fibrosis in heart failure.

Proteomic Profile of the ICAM1 p.K56M HFpEF Risk Variant

A common missense variant in ICAM1 among African American individuals (rs5491; pK56M) has been associated with risk of heart failure with preserved ejection fraction (HFpEF), but the pathways that lead to HFpEF among those with this variant are not clear. In this analysis of 92 circulating proteins and their associated networks, we identified 7 circulating inflammatory proteins associated with rs5491 among >600 African American individuals. Using weighted coexpression network analysis, 3 protein networks were identified, one of which was associated with rs5491. This protein network was most highly represented by members of the tumor necrosis receptor superfamily. The rs5491 variant demonstrated an inflammatory proteomic profile in a separate cohort of African American individuals. This analysis identifies inflammatory pathways that may drive HFpEF among African American individuals with the ICAM1 pK56M (rs5491) variant.

Computational investigation of the role of ventricular remodelling in HFpEF: The key to phenotype dissection

Recent clinical studies have reported that heart failure with preserved ejection fraction (HFpEF) can be divided into two phenotypes based on the range of ejection fraction (EF), namely HFpEF with higher EF and HFpEF with lower EF. These phenotypes exhibit distinct left ventricle (LV) remodelling patterns and dynamics. However, the influence of LV remodelling on various LV functional indices and the underlying mechanics for these two phenotypes are not well understood. To address these issues, this study employs a coupled finite element analysis (FEA) framework to analyse the impact of various ventricular remodelling patterns, specifically concentric remodelling (CR), concentric hypertrophy (CH), and eccentric hypertrophy (EH), with and without LV wall thickening on LV functional indices. Further, the geometries with a moderate level of remodelling from each pattern are subjected to fibre stiffening and contractile impairment to examine their effect in replicating the different features of HFpEF. The results show that with severe CR, LV could exhibit the characteristics of HFpEF with higher EF, as observed in recent clinical studies. Controlled fibre stiffening can simultaneously increase the end-diastolic pressure (EDP) and reduce the peak longitudinal strain (ell) without significant reduction in EF, facilitating the moderate CR geometries to fit into this phenotype. Similarly, fibre stiffening can assist the CH and 'EH with wall thickening' cases to replicate HFpEF with lower EF. These findings suggest that potential treatment for these two phenotypes should target the bio-origins of their distinct ventricular remodelling patterns and the extent of myocardial stiffening.

Inhibitors of NLRP3 Inflammasome Formation: A Cardioprotective Role for the Gasotransmitters Carbon Monoxide, Nitric Oxide, and Hydrogen Sulphide in Acute Myocardial Infarction

Myocardial ischaemia reperfusion injury (IRI) occurring from acute coronary artery disease or cardiac surgical interventions such as bypass surgery can result in myocardial dysfunction, presenting as, myocardial "stunning", arrhythmias, infarction, and adverse cardiac remodelling, and may lead to both a systemic and a localised inflammatory response. This localised cardiac inflammatory response is regulated through the nucleotide-binding oligomerisation domain (NACHT), leucine-rich repeat (LRR)-containing protein family pyrin domain (PYD)-3 (NLRP3) inflammasome, a multimeric structure whose components are present within both cardiomyocytes and in cardiac fibroblasts. The NLRP3 inflammasome is activated via numerous danger signals produced by IRI and is central to the resultant innate immune response. Inhibition of this inherent inflammatory response has been shown to protect the myocardium and stop the occurrence of the systemic inflammatory response syndrome following the re-establishment of cardiac circulation. Therapies to prevent NLRP3 inflammasome formation in the clinic are currently lacking, and therefore, new pharmacotherapies are required. This review will highlight the role of the NLRP3 inflammasome within the myocardium during IRI and will examine the therapeutic value of inflammasome inhibition with particular attention to carbon monoxide, nitric oxide, and hydrogen sulphide as potential pharmacological inhibitors of NLRP3 inflammasome activation.

Heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) accounts for nearly half of all heart failure cases and has a prevalence that is expected to rise with the growing ageing population. HFpEF is associated with significant morbidity and mortality. Specific HFpEF risk factors include age, diabetes, hypertension, obesity and atrial fibrillation. Haemodynamic contributions to HFpEF include changes in left ventricular structure, diastolic and systolic dysfunction, left atrial myopathy, pulmonary hypertension, right ventricular dysfunction, chronotropic incompetence, and vascular dysfunction. Inflammation, fibrosis, impaired nitric oxide signalling, sarcomere dysfunction, and mitochondrial and metabolic defects contribute to the cellular and molecular changes observed in HFpEF. HFpEF impacts multiple organ systems beyond the heart, including the skeletal muscle, peripheral vasculature, lungs, kidneys and brain. The diagnosis of HFpEF can be made in individuals with signs and symptoms of heart failure with abnormality in natriuretic peptide levels or evidence of cardiopulmonary congestion, facilitated by the use of HFpEF risk scores and additional imaging and testing with the exclusion of HFpEF mimics. Management includes initiation of guideline-directed medical therapy and management of comorbidities. Given the significant impact of HFpEF on quality of life, future research efforts should include a particular focus on how patients can live better with this disease.

Smoking paradox in coronary function and structure of acute ST-segment elevation myocardial infarction patients treated with primary percutaneous coronary intervention

BACKGROUND

The Smoking paradox has generated inconsistent findings concerning the clinical prognosis of acute ST-segment elevation myocardial infarction (STEMI) patients, while providing limited insights into coronary anatomy and function which are crucial prognostic factors. Therefore, this study aimed to further investigate the existence of smoking paradox in coronary anatomy and function.

METHODS

This study divided STEMI patients into smokers and non-smokers. Quantitative coronary angiography, angiography‑derived microcirculatory resistance (AMR) and quantitative flow ratio (QFR) were utilized to analyze coronary anatomy and function. These parameters were compared using multivariable analysis and propensity score matching. The clinical outcomes were evaluated using Kaplan-Meier curve and Cox regression.

RESULTS

The study included 1258 patients, with 730 in non-smoker group and 528 in smoker group. Smokers were significantly younger, predominantly male, and had fewer comorbidities. Without adjusting for confounders, smokers exhibited larger lumen diameter [2.03(1.45-2.57) vs. 1.90(1.37-2.49), P = 0.033] and lower AMR [244(212-288) vs. 260(218-301), P = 0.006]. After matching and multivariate adjustment, smokers exhibited inversely smaller lumen diameter [1.97(1.38-2.50) vs. 2.15(1.63-2.60), P = 0.002] and higher incidence of coronary microvascular dysfunction [233(53.9%) vs. 190(43.6%), P = 0.002], but showed similar AMR and clinical outcomes compared to non-smokers. There was no difference in QFR between two groups.

CONCLUSION

Smoking among STEMI patients undergoing pPCI was associated with smaller lumen diameter and higher occurrence of coronary microvascular dysfunction, although it had no further impact on clinical prognosis. The smoking paradox observed in coronary anatomy or function may be explained by younger age, gender, and lower prevalence of comorbidities.

Comprehensive Analysis of Immune Cell Infiltration and M2-Like Macrophage Biomarker Expression Patterns in Atrial Fibrillation

Background

Macrophages play a crucial role in the progression of AF, closely linked to atrial inflammation and myocardial fibrosis. However, the functions and molecular mechanisms of different phenotypic macrophages in AF are not well understood. This study aims to analyze the infiltration characteristics of atrial immune cells in AF patients and further explore the role and molecular expression patterns of M2 macrophage-related genes in AF.

Methods

This study integrates single-cell and large-scale sequencing data to analyze immune cell infiltration and molecular characterization of the LAA in patients with AF, using SR as a control group. CIBERSORT assesses immune cell types in LAA tissues; WGCNA identifies signature genes; cell clustering analyzes cell types and subpopulations; cell communication explores macrophage interactions; hdWGCNA identifies M2 macrophage gene modules in AF. AF biomarkers are identified using LASSO and Random Forest, validated with ROC curves and RT-qPCR. Potential molecular mechanisms are inferred through TF-miRNA-mRNA networks and single-gene enrichment analyses.

Results

Myeloid cell subsets varied considerably between the AF and SR groups, with a significant increase in M2 macrophages in the AF group. Signals of inflammation and matrix remodeling were observed in AF. M2 macrophage-related genes IGF1, PDK4, RAB13, and TMEM176B were identified as AF biomarkers, with RAB13 and TMEM176B being novel markers. A TF-miRNA-mRNA network was constructed using target genes, which are enriched in the PPAR signaling pathway and fatty acid metabolism.

Conclusion

Over infiltration of M2 macrophages may be an important factor in the progression of AF. The M2 macrophage-related genes IGF1, RAB13, TMEM176B and PDK4 may regulate the progression of AF through the PPAR signaling pathway and fatty acid metabolism.

Differential Expression of Circulating miRNAs and Carfilzomib-Related Cardiovascular Adverse Events in Patients with Multiple Myeloma

This study investigates the association between circulating microRNA (miRNA) expression and cardiovascular adverse events (CVAE) in multiple myeloma (MM) patients treated with a carfilzomib (CFZ)-based regimen. A cohort of 60 MM patients from the Prospective Observation of Cardiac Safety with Proteasome Inhibitor (PROTECT) study was analyzed. Among these, 31 patients (51.6%) developed CVAE post-CFZ treatment. The Taqman OpenArray Human microRNA panels were used for miRNA profiling. We identified 13 differentially expressed miRNAs at baseline, with higher expressions of miR-125a-5p, miR-15a-5p, miR-18a-3p, and miR-152-3p and lower expression of miR-140-3p in patients who later developed CVAE compared to those free of CVAE, adjusting for age, gender, race, and higher B-type natriuretic peptide levels. We also identified three miRNAs, including miR-150-5p, that were differentially expressed in patients with and without CVAE post-treatment. Additionally, five miRNAs responded differently to CFZ treatment in CVAE vs. non-CVAE patients, including significantly elevated post-treatment expression of miR-140-3p and lower expressions of miR-598, miR-152, miR-21, and miR-323a in CVAE patients. Pathway enrichment analysis highlighted the involvement of these miRNAs in cardiovascular diseases and vascular processes. These findings suggest that specific miRNAs could serve as predictive biomarkers for CVAE and provide insights into the underlying mechanisms of CFZ-CVAE. Further investigation is warranted before these findings can be applied in clinical settings.

Exploring Sirtuins: New Frontiers in Managing Heart Failure with Preserved Ejection Fraction

With increasing research, the sirtuin (SIRT) protein family has become increasingly understood. Studies have demonstrated that SIRTs can aid in metabolism and affect various physiological processes, such as atherosclerosis, heart failure (HF), hypertension, type 2 diabetes, and other related disorders. Although the pathogenesis of HF with preserved ejection fraction (HFpEF) has not yet been clarified, SIRTs have a role in its development. Therefore, SIRTs may offer a fresh approach to the diagnosis, treatment, and prevention of HFpEF as a novel therapeutic intervention target.

Microvascular Dysfunction across the Spectrum of Heart Failure Pathology: Pathophysiology, Clinical Features and Therapeutic Implications

Coronary microvascular dysfunction (CMD) plays a crucial role across the spectrum of heart failure (HF) pathology, contributing to disease development, progression, and outcomes. The pathophysiological mechanisms linking CMD to HF are complex and still not completely understood and include chronic inflammation, oxidative stress, and neurohormonal activation. Despite the diagnostic and prognostic relevance in patients with HF, there is no specific therapeutic strategy targeting CMD to date. Moreover, the diagnosis of this clinical condition is challenging. In this review article, we aim to discuss the different clinical pathogenetic mechanisms linking CMD to HF across the different spectra of these diseases, their prognostic relevance, and the possible therapeutic targets along with the remaining knowledge gaps in the field.

Heart Failure With Preserved Ejection Fraction: Will Cardiac Magnetic Imaging Impact on Diagnosis, Treatment, and Outcomes?: Explaining the Need for Advanced Imaging to Clinical Stakeholders

Clinicians frequently equate symptoms of volume overload to heart failure (HF) but such generalization may preclude diagnostic or etiologic precision essential to optimizing outcomes. HF itself must be specified as the disparate types of cardiac pathology have been traditionally surmised by examination of left ventricular (LV) ejection fraction (EF) as either HF with preserved LVEF (HFpEF-LVEF >50%) or reduced LVEF of (HFrEF-LVEF <40%). More recent data support a third, potentially transitional HF subtype, but therapy, assessment, and prognosis have been historically dictated within the corresponding LV metrics determined by echocardiography. The present effort asks whether this historically dominant role of echocardiography is now shifting slightly, becoming instead a shared if not complimentary test. Will there be a gradual increasing profile for cardiac magnetic resonance as the attempt to further refine our understanding, diagnostic accuracy, and outcomes for HFpEF is attempted?

Impact of Pre-Transplant Left Ventricular Diastolic Pressure on Primary Graft Dysfunction after Lung Transplantation: A Narrative Review

Lung transplantation (LT) constitutes the last therapeutic option for selected patients with end-stage respiratory disease. Primary graft dysfunction (PGD) is a form of severe lung injury, occurring in the first 72 h following LT and constitutes the most common cause of early death after LT. The presence of pulmonary hypertension (PH) has been reported to favor PGD development, with a negative impact on patients' outcomes while complicating medical management. Although several studies have suggested a potential association between pre-LT left ventricular diastolic dysfunction (LVDD) and PGD occurrence, the underlying mechanisms of such an association remain elusive. Importantly, the heterogeneity of the study protocols and the various inclusion criteria used to define the diastolic dysfunction in those patients prevents solid conclusions from being drawn. In this review, we aim at summarizing PGD mechanisms, risk factors, and diagnostic criteria, with a further focus on the interplay between LVDD and PGD development. Finally, we explore the predictive value of several diastolic dysfunction diagnostic parameters to predict PGD occurrence and severity.

Macrophages in cardiovascular diseases: molecular mechanisms and therapeutic targets

The immune response holds a pivotal role in cardiovascular disease development. As multifunctional cells of the innate immune system, macrophages play an essential role in initial inflammatory response that occurs following cardiovascular injury, thereby inducing subsequent damage while also facilitating recovery. Meanwhile, the diverse phenotypes and phenotypic alterations of macrophages strongly associate with distinct types and severity of cardiovascular diseases, including coronary heart disease, valvular disease, myocarditis, cardiomyopathy, heart failure, atherosclerosis and aneurysm, which underscores the importance of investigating macrophage regulatory mechanisms within the context of specific diseases. Besides, recent strides in single-cell sequencing technologies have revealed macrophage heterogeneity, cell-cell interactions, and downstream mechanisms of therapeutic targets at a higher resolution, which brings new perspectives into macrophage-mediated mechanisms and potential therapeutic targets in cardiovascular diseases. Remarkably, myocardial fibrosis, a prevalent characteristic in most cardiac diseases, remains a formidable clinical challenge, necessitating a profound investigation into the impact of macrophages on myocardial fibrosis within the context of cardiac diseases. In this review, we systematically summarize the diverse phenotypic and functional plasticity of macrophages in regulatory mechanisms of cardiovascular diseases and unprecedented insights introduced by single-cell sequencing technologies, with a focus on different causes and characteristics of diseases, especially the relationship between inflammation and fibrosis in cardiac diseases (myocardial infarction, pressure overload, myocarditis, dilated cardiomyopathy, diabetic cardiomyopathy and cardiac aging) and the relationship between inflammation and vascular injury in vascular diseases (atherosclerosis and aneurysm). Finally, we also highlight the preclinical/clinical macrophage targeting strategies and translational implications.

Cardiac sympathetic overdrive, M2 macrophage activation and fibroblast heterogeneity are associated with cardiac remodeling in a chronic pressure overload rat model of HFpEF

Heart failure with preserved ejection fraction (HFpEF) is a multifaceted pathogenesis disease and the exact mechanisms driving HFpEF have not been completely elucidated. Pressure overload hypertrophy (POH) related fibroblasts and M2 macrophages in HFpEF myocardium have been recently identified and are now of great interest. Sympathetic overdrive has also been implicated in HFpEF. This study is designed to dynamically observe the potential roles of aforementioned mechanisms in pathological remodeling and cardiac dysfunction in chronic PO rats. Surgical constriction of the abdominal aorta was used for induction of HFpEF. Echocardiography, electrocardiogram, hemodynamic measurement, hematoxylin and eosin staining, Masson staining, immunohistochemistry and immunofluorescence were performed to assess the changes in heart dysfunction, cardiac remodeling and driving mechanisms at different time points (2, 18, 24 weeks). The PO induced HFpEF model was well established, which was confirmed by the persistent increase in carotid artery systolic and diastolic blood pressure, and left ventricle hypertrophy at the corresponding postoperative stage. Meanwhile, PO hypertrophy gradually developed into HFpEF, associated with QT and QTc intervals prolongation, normal systolic (EF was maintained at >50%) but impaired diastolic function (increasing LVEDP and LV -dP/dtmin, abnormal E/A ratio), increased myocytes size, and observed relatively slight inflammatory infiltration but robust reactive fibrosis. IHC staining further confirmed that macrophages (CD68) but not neutrophils (MPO) or T cells (CD3) accounted for a predominant proportion of infiltrating cells. Mechanistically, we found that the infiltrating macrophages in the heart expressed high levels of CD206 which was simultaneously adjacent to POH fibroblasts appeared to overexpression of α-SMA in PO rats at late stages. Interestingly, we distinguished two different POHF sub-populations during PO induced HFpEF development, according to non overlapping signals of α-SMA and PDGFRα/β proteins. Additionally, PO led to a pronounced exaggeration in sympathetic fibers at all time points. These findings suggest that the establishing model here begins with cardiac sympathetic overdrive, subsequently along with immune cells especially M2 macrophage accumulation and fibroblast heterogeneity at later stages is associated with the development of cardiac maladaptive remodeling and diastolic dysfunction thus further progression to HFpEF.

Exploring the therapeutic potential of tetrahydrobiopterin for heart failure with preserved ejection fraction: A path forward

A large number of patients are affected by classical heart failure (HF) symptomatology with preserved ejection fraction (HFpEF) and multiorgan syndrome. Due to high morbidity and mortality rate, hospitalization and mortality remain serious socioeconomic problems, while the lack of effective pharmacological or device treatment means that HFpEF presents a major unmet medical need. Evidence from clinical and basic studies demonstrates that systemic inflammation, increased oxidative stress, and impaired mitochondrial function are the common pathological mechanisms in HFpEF. Tetrahydrobiopterin (BH4), beyond being an endogenous co-factor for catalyzing the conversion of some essential biomolecules, has the capacity to prevent systemic inflammation, enhance antioxidant resistance, and modulate mitochondrial energy production. Therefore, BH4 has emerged in the last decade as a promising agent to prevent or reverse the progression of disorders such as cardiovascular disease. In this review, we cover the clinical progress and limitations of using downstream targets of nitric oxide (NO) through NO donors, soluble guanylate cyclase activators, phosphodiesterase inhibitors, and sodium-glucose co-transporter 2 inhibitors in treating cardiovascular diseases, including HFpEF. We discuss the use of BH4 in association with HFpEF, providing new evidence for its potential use as a pharmacological option for treating HFpEF.

Use of Statins in Heart Failure with Preserved Ejection Fraction: Current Evidence and Perspectives

Systemic inflammation and coronary microvascular endothelial dysfunction are essential pathophysiological factors in heart failure (HF) with preserved ejection fraction (HFpEF) that support the use of statins. The pleiotropic properties of statins, such as anti-inflammatory, antihypertrophic, antifibrotic, and antioxidant effects, are generally accepted and may be beneficial in HF, especially in HFpEF. Numerous observational clinical trials have consistently shown a beneficial prognostic effect of statins in patients with HFpEF, while the results of two larger trials in patients with HFrEF have been controversial. Such differences may be related to a more pronounced impact of the pleiotropic properties of statins on the pathophysiology of HFpEF and pro-inflammatory comorbidities (arterial hypertension, diabetes mellitus, obesity, chronic kidney disease) that are more common in HFpEF. This review discusses the potential mechanisms of statin action that may be beneficial for patients with HFpEF, as well as clinical trials that have evaluated the statin effects on left ventricular diastolic function and clinical outcomes in patients with HFpEF.

HBI-8000 improves heart failure with preserved ejection fraction via the TGF-β1/MAPK signalling pathway

Heart failure with preserved ejection fraction (HFpEF) accounts for approximately 50% of total heart failure patients and is characterized by peripheral circulation, cardiac remodelling and comorbidities (such as advanced age, obesity, hypertension and diabetes) with limited treatment options. Chidamide (HBI-8000) is a domestically produced benzamide-based histone deacetylase isoform-selective inhibitor used for the treatment of relapsed refractory peripheral T-cell lymphomas. Based on our in vivo studies, we propose that HBI-8000 exerts its therapeutic effects by inhibiting myocardial fibrosis and myocardial hypertrophy in HFpEF patients. At the cellular level, we found that HBI-8000 inhibits AngII-induced proliferation and activation of CFs and downregulates the expression of fibrosis-related factors. In addition, we observed that the HFpEF group and AngII stimulation significantly increased the expression of TGF-β1 as well as phosphorylated p38MAPK, JNK and ERK, whereas the expression of the above factors was significantly reduced after HBI-8000 treatment. Activation of the TGF-β1/MAPK pathway promotes the development of fibrotic remodelling, and pretreatment with SB203580 (p38MAPK inhibitor) reverses this pathological change. In conclusion, our data suggest that HBI-8000 inhibits fibrosis by modulating the TGF-β1/MAPK pathway thereby improving HFpEF. Therefore, HBI-8000 may become a new hope for the treatment of HFpEF patients.

M2 macrophage-derived paracrine factor TNFSF13 affects the fibrogenic alterations in endothelial cells and cardiac fibroblasts by mediating the NF-κB and Akt pathway

Heart failure remains a global threaten to public health, cardiac fibrosis being a crucial event during the development and progression of heart failure. Reportedly, M2 macrophages might affect endothelial cell (ECs) and fibroblast proliferation and functions through paracrine signaling, participating in myocardial fibrosis. In this study, differentially expressed paracrine factors between M0/1 and M2 macrophages were analyzed and the expression of TNFSF13 was most significant in M2 macrophages. Culture medium (CM) of M2 (M2 CM) coculture to ECs and cardiac fibroblasts (CFbs) significantly promoted the cell proliferation of ECs and CFbs, respectively, and elevated α-smooth muscle actin (α-SMA), collagen I, and vimentin levels within both cell lines; moreover, M2 CM-induced changes in ECs and CFbs were partially abolished by TNFSF13 knockdown in M2 macrophages. Lastly, the NF-κB and Akt signaling pathways were proved to participate in TNFSF13-mediated M2 CM effects on ECs and CFbs. In conclusion, TNFSF13, a paracrine factor upregulated in M2 macrophages, could mediate the promotive effects of M2 CM on EC and CFb proliferation and fibrogenic alterations.

Phosphodiesterase in heart and vessels: from physiology to diseases

Phosphodiesterases (PDEs) are a superfamily of enzymes that hydrolyze cyclic nucleotides, including cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP). Both cyclic nucleotides are critical secondary messengers in the neurohormonal regulation in the cardiovascular system. PDEs precisely control spatiotemporal subcellular distribution of cyclic nucleotides in a cell- and tissue-specific manner, playing critical roles in physiological responses to hormone stimulation in the heart and vessels. Dysregulation of PDEs has been linked to the development of several cardiovascular diseases, such as hypertension, aneurysm, atherosclerosis, arrhythmia, and heart failure. Targeting these enzymes has been proven effective in treating cardiovascular diseases and is an attractive and promising strategy for the development of new drugs. In this review, we discuss the current understanding of the complex regulation of PDE isoforms in cardiovascular function, highlighting the divergent and even opposing roles of PDE isoforms in different pathogenesis.

Obesity, heart failure with preserved ejection fraction, and the role of glucagon-like peptide-1 receptor agonists

Heart failure with preserved ejection fraction (HFpEF) has a high prevalence, affecting more than 50% of patients with heart failure. HFpEF is associated with multiple comorbidities, and obesity is one of the most common. A distinct phenotype has been proposed for obese patients with HFpEF. Recent data show the beneficial role of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) for weight loss in diabetic and non-diabetic patients with obesity or overweight when given as adjunctive therapy to diet and exercise. The mechanisms of action are related to paracrine and endocrine signalling pathways within the gastrointestinal tract, pancreas, and central nervous system that delay gastric emptying, decrease appetite, augment pancreatic beta-cell insulin secretion, and suppress pancreatic glucagon release. These drugs are therefore potentially indicated for treatment of patients with HFpEF and obesity or overweight. Efficacy and safety need to be shown by clinical trials with a first one, Semaglutide Treatment Effect in People with obesity and heart failure with preserved ejection fraction (STEP HFpEF), recently concluded. The aim of the present review is to provide the pathophysiological and pharmacological rationale for GLP-1 RA administration to obese patients with HFpEF.

Interplay between Senescence and Macrophages in Diabetic Cardiomyopathy: A Review of the Potential Role of GDF-15 and Klotho

Type 2 diabetes mellitus (T2DM) is a critical health problem, with 700 million diagnoses expected worldwide by 2045. Uncontrolled high blood glucose levels can lead to serious complications, including diabetic cardiomyopathy (DCM). Diabetes induces cardiovascular aging and inflammation, increasing cardiomyopathy risk. DCM is characterized by structural and functional abnormalities in the heart. Growing evidence suggests that cellular senescence and macrophage-mediated inflammation participate in the pathogenesis and progression of DCM. Evidence indicates that growth differentiation factor-15 (GDF-15), a protein that belongs to the transforming growth factor-beta (TGF-β) superfamily, is associated with age-related diseases and exerts an anti-inflammatory role in various disease models. Although further evidence suggests that GDF-15 can preserve Klotho, a transmembrane antiaging protein, emerging research has elucidated the potential involvement of GDF-15 and Klotho in the interplay between macrophages-induced inflammation and cellular senescence in the context of DCM. This review explores the intricate relationship between senescence and macrophages in DCM while highlighting the possible contributions of GDF-15 and Klotho.

Relationship between heart failure and intestinal inflammation in infants with congenital heart disease

OBJECTIVE

The association between heart failure (HF) and intestinal inflammation caused by a disturbed intestinal microbiota in infants with congenital heart disease (CHD) was investigated.

METHODS

Twenty infants with HF and CHD who were admitted to our hospital between October 2021 and March 2022 were included in this study. Twenty age- and sex-matched infants without HF at our hospital were selected as the control group. Faecal samples were obtained from each participant and analysed by enzyme-linked immunoassay and 16 S rDNA sequencing to assess intestinal inflammatory factors and the microbiota.

RESULTS

The levels of intestinal inflammatory factors, including IL-1β, IL-4, IL-6, IL-17 A and TNF-α, were greatly increased, while the levels of IL-10 were significantly decreased in the HF group compared to the control group (p < 0.05). The intestinal microbial diversity of patients in the HF group was markedly lower than that in the control group (p < 0.05). The abundance of Enterococcus was significantly increased in the HF group compared to the control group (p < 0.05), but the abundance of Bifidobacterium was significantly decreased in the HF group compared to the control group (p < 0.05). The diversity of the intestinal microbiota was negatively correlated with the levels of IL-1β, IL-4, IL-6 and TNF-α in the intestinal tract but was positively correlated with that of IL-10. The abundance of Enterococcus was positively associated with the levels of IL-1β, IL-4, IL-6 and TNF-α in the intestinal tract but was negatively correlated with that of IL-10. NT-proBNP was positively associated with the levels of IL-1β, IL-4, IL-6 and TNF-α in the HF group but was negatively correlated with that of IL-10. The heart function score was positively associated with the levels of IL-1β, IL-4, IL-6 and TNF-α in the HF group but was negatively correlated with that of IL-10.

CONCLUSIONS

Infants with CHD-related HF had a disordered intestinal microbiota, decreased diversity of intestinal microbes, increased levels of pathogenic bacteria and decreased levels of beneficial bacteria. The increased abundance of Enterococcus and the significant decrease in the diversity of the intestinal microbiota may exacerbate the intestinal inflammatory response, which may be associated with the progression of HF.