Inflammation in HFpEF: Key or circumstantial?

Daucosterol alleviates heart failure with preserved ejection fraction through activating PPARα pathway

Heart failure with preserved ejection fraction (HFpEF) has been increasing in the population in recent years and is mainly characterized by preserved left ventricle ejection fraction (LVEF), diastolic dysfunction and systemic inflammation. Daucosterol (DAU), a glycoside of β-sitosterol, has good anti-inflammatory and antioxidative properties; however, its effects and mechanisms in HFpEF have not been investigated. To detect whether DAU could alleviate HFpEF, C57BL/6J male mice were fed with N-nitro-l-arginine methyl ester (L-NAME) in drinking water and high fat diet (HFD) and treated with DAU by gavage (i.g.) for 10 weeks. The results showed that DAU treatment significantly alleviated HFpEF in mice. Mechanistically, by controlling PPARα and preventing NF-κB phosphorylation, DAU reduced oxidative stress and the inflammatory response. In conclusion, our study provides a new clue for natural product DAU in alleviating HFpEF.

Glucagon Receptor Antagonist for Heart Failure With Preserved Ejection Fraction

BACKGROUND

Heart failure with preserved ejection fraction (HFpEF) is an emerging major unmet need and one of the most significant clinic challenges in cardiology. The pathogenesis of HFpEF is associated with multiple risk factors. Hypertension and metabolic disorders associated with obesity are the 2 most prominent comorbidities observed in patients with HFpEF. Although hypertension-induced mechanical overload has long been recognized as a potent contributor to heart failure with reduced ejection fraction, the synergistic interaction between mechanical overload and metabolic disorders in the pathogenesis of HFpEF remains poorly characterized.

METHOD

We investigated the functional outcome and the underlying mechanisms from concurrent mechanic and metabolic stresses in the heart by applying transverse aortic constriction in lean C57Bl/6J or obese/diabetic B6.Cg-Lepob/J (ob/ob) mice, followed by single-nuclei RNA-seq and targeted manipulation of a top-ranked signaling pathway differentially affected in the 2 experimental cohorts.

RESULTS

In contrast to the post-transverse aortic constriction C57Bl/6J lean mice, which developed pathological features of heart failure with reduced ejection fraction over time, the post-transverse aortic constriction ob/ob mice showed no significant changes in ejection fraction but developed characteristic pathological features of HFpEF, including diastolic dysfunction, worsened cardiac hypertrophy, and pathological remodeling, along with further deterioration of exercise intolerance. Single-nuclei RNA-seq analysis revealed significant transcriptome reprogramming in the cardiomyocytes stressed by both pressure overload and obesity/diabetes, markedly distinct from the cardiomyocytes singularly stressed by pressure overload or obesity/diabetes. Furthermore, glucagon signaling was identified as the top-ranked signaling pathway affected in the cardiomyocytes associated with HFpEF. Treatment with a glucagon receptor antagonist significantly ameliorated the progression of HFpEF-related pathological features in 2 independent preclinical models. Importantly, cardiomyocyte-specific genetic deletion of the glucagon receptor also significantly improved cardiac function in response to pressure overload and metabolic stress.

CONCLUSIONS

These findings identify glucagon receptor signaling in cardiomyocytes as a critical determinant of HFpEF progression and provide proof-of-concept support for glucagon receptor antagonism as a potential therapy for the disease.

Characterization of systolic and diastolic function, alongside proteomic profiling, in doxorubicin-induced cardiovascular toxicity in mice

BACKGROUND

The anthracycline doxorubicin (DOX) is a highly effective anticancer agent, especially in breast cancer and lymphoma. However, DOX can cause cancer therapy-related cardiovascular toxicity (CTR-CVT) in patients during treatment and in survivors. Current diagnostic criteria for CTR-CVT focus mainly on left ventricular systolic dysfunction, but a certain level of damage is required before it can be detected. As diastolic dysfunction often precedes systolic dysfunction, the current study aimed to identify functional and molecular markers of DOX-induced CTR-CVT with a focus on diastolic dysfunction.

METHODS

Male C57BL/6J mice were treated with saline or DOX (4 mg/kg, weekly i.p. injection) for 2 and 6 weeks (respectively cumulative dose of 8 and 24 mg/kg) (n = 8 per group at each time point). Cardiovascular function was longitudinally investigated using echocardiography and invasive left ventricular pressure measurements. Subsequently, at both timepoints, myocardial tissue was obtained for proteomics (liquid-chromatography with mass-spectrometry). A cohort of patients with CTR-CVT was used to complement the pre-clinical findings.

RESULTS

DOX-induced a reduction in left ventricular ejection fraction from 72 ± 2% to 55 ± 1% after 2 weeks (cumulative 8 mg/kg DOX). Diastolic dysfunction was demonstrated as prolonged relaxation (increased tau) and heart failure was evident from pulmonary edema after 6 weeks (cumulative 24 mg/kg DOX). Myocardial proteomic analysis revealed an increased expression of 12 proteins at week 6, with notable upregulation of SERPINA3N in the DOX-treated animals. The human ortholog SERPINA3 has previously been suggested as a marker in CTR-CVT. Upregulation of SERPINA3N was confirmed by western blot, immunohistochemistry, and qPCR in murine hearts. Thereby, SERPINA3N was most abundant in the endothelial cells. In patients, circulating SERPINA3 was increased in plasma of CTR-CVT patients but not in cardiac biopsies.

CONCLUSION

We showed that mice develop heart failure with impaired systolic and diastolic function as result of DOX treatment. Additionally, we could identify increased SERPINA3 levels in the mice as well as patients with DOX-induced CVT and demonstrated expression of SERPINA3 in the heart itself, suggesting that SERPINA3 could serve as a novel biomarker.

High-sensitivity C-reactive protein in heart failure with preserved ejection fraction: Findings from TOPCAT

BACKGROUND

Inflammation plays a central role in the genesis and progression of heart failure with preserved ejection fraction (HFpEF). C-reactive protein (CRP) is widely used as means to assess systemic inflammation, and elevated levels of CRP have been associated with poor HF prognosis. Identification of chronic low-grade inflammation in outpatients can be performed measuring high-sensitivity CRP (hsCRP). The clinical characteristics and outcome associations of a pro-inflammatory state among outpatients with HFpEF requires further study.

AIMS

Using a biomarker subset of TOPCAT-Americas (NCT00094302), we aim to characterize HFpEF patients according to hsCRP levels and study the prognostic associations of hsCRP.

METHODS

hsCRP was available in a subset of 232 participants. Comparisons were performed between patients with hsCRP <2 mg/L and ≥ 2 mg/L. Cox regression models were used to study the association between hsCRP and the study outcomes.

RESULTS

Compared to patients with hsCRP <2 mg/L (n = 89, 38%), those with hsCRP ≥2 mg/L (n = 143, 62%) had more frequent HF hospitalizations prior to randomization, chronic obstructive pulmonary disease, orthopnea, higher body mass index, and worse health-related quality-of-life. A hsCRP level ≥ 2 mg/L was associated with an increased risk of cardiovascular death and HF hospitalizations: hsCRP ≥2 mg/L vs <2 mg/L adjusted HR 2.36, 95%CI 1.27-4.38, P = 0.006. Spironolactone did not influence hsCRP levels from baseline to month 12: gMean ratio = 1.11, 95%CI 0.87-1.42, P = 0.39.

CONCLUSIONS

A hsCRP ≥2 mg/L identified HFpEF patients with a high risk of HF events and cardiovascular mortality. Spironolactone did not influence hsCRP levels at 12 months.

Heart Failure with Preserved Ejection Fraction: The Pathophysiological Mechanisms behind the Clinical Phenotypes and the Therapeutic Approach

Heart failure (HF) with preserved ejection fraction (HFpEF) is an increasingly frequent form and is estimated to be the dominant form of HF. On the other hand, HFpEF is a syndrome with systemic involvement, and it is characterized by multiple cardiac and extracardiac pathophysiological alterations. The increasing prevalence is currently reaching epidemic levels, thereby making HFpEF one of the greatest challenges facing cardiovascular medicine today. Compared to HF with reduced ejection fraction (HFrEF), the medical attitude in the case of HFpEF was a relaxed one towards the disease, despite the fact that it is much more complex, with many problems related to the identification of physiopathogenetic mechanisms and optimal methods of treatment. The current medical challenge is to develop effective therapeutic strategies, because patients suffering from HFpEF have symptoms and quality of life comparable to those with reduced ejection fraction, but the specific medication for HFrEF is ineffective in this situation; for this, we must first understand the pathological mechanisms in detail and correlate them with the clinical presentation. Another important aspect of HFpEF is the diversity of patients that can be identified under the umbrella of this syndrome. Thus, before being able to test and develop effective therapies, we must succeed in grouping patients into several categories, called phenotypes, depending on the pathological pathways and clinical features. This narrative review critiques issues related to the definition, etiology, clinical features, and pathophysiology of HFpEF. We tried to describe in as much detail as possible the clinical and biological phenotypes recognized in the literature in order to better understand the current therapeutic approach and the reason for the limited effectiveness. We have also highlighted possible pathological pathways that can be targeted by the latest research in this field.

Locomotor and respiratory muscle abnormalities in HFrEF and HFpEF

Heart failure (HF) is a chronic and progressive syndrome affecting worldwide billions of patients. Exercise intolerance and early fatigue are hallmarks of HF patients either with a reduced (HFrEF) or a preserved (HFpEF) ejection fraction. Alterations of the skeletal muscle contribute to exercise intolerance in HF. This review will provide a contemporary summary of the clinical and molecular alterations currently known to occur in the skeletal muscles of both HFrEF and HFpEF, and thereby differentiate the effects on locomotor and respiratory muscles, in particular the diaphragm. Moreover, current and future therapeutic options to address skeletal muscle weakness will be discussed focusing mainly on the effects of exercise training.

Development of heart failure with preserved ejection fraction is independent of eosinophils in a preclinical model

The increasing burden of heart failure with preserved ejection fraction (HFpEF) has become a global health problem. HFpEF is characterized by systematic inflammation, cardiac metabolic remodeling, and fibrosis. Eosinophils act as an essential but generally overlooked subgroup of white blood cells, which participate in cardiac fibrosis, as reported in several recent studies. Herein, we explored the role of eosinophils in a "two-hit" preclinical HFpEF model. The peripheral eosinophil counts were comparable between the normal chow and HFpEF mice. Deficiency of eosinophils failed to alter the phenotype of HFpEF. Conclusively, the development of HFpEF is independent of eosinophils in terms of the functional, biochemical, and histological results.

Clonal Hematopoiesis of Indeterminate Potential From a Heart Failure Specialist's Point of View

Clonal hematopoiesis of indeterminate potential (CHIP) is a common bone marrow abnormality induced by age-related DNA mutations, which give rise to proinflammatory immune cells. These immune cells exacerbate atherosclerotic cardiovascular disease and may induce or accelerate heart failure. The mechanisms involved are complex but point toward a central role for proinflammatory macrophages and an inflammasome-dependent immune response (IL-1 [interleukin-1] and IL-6 [interleukin-6]) in the atherosclerotic plaque or directly in the myocardium. Intracardiac inflammation may decrease cardiac function and induce cardiac fibrosis, even in the absence of atherosclerotic cardiovascular disease. The pathophysiology and consequences of CHIP may differ among implicated genes as well as subgroups of patients with heart failure, based on cause (ischemic versus nonischemic) and ejection fraction (reduced ejection fraction versus preserved ejection fraction). Evidence is accumulating that CHIP is associated with cardiovascular mortality in ischemic and nonischemic heart failure with reduced ejection fraction and involved in the development of heart failure with preserved ejection fraction. CHIP and corresponding inflammatory pathways provide a highly potent therapeutic target. Randomized controlled trials in patients with well-phenotyped heart failure, where readily available anti-inflammatory therapies are used to intervene with clonal hematopoiesis, may pave the way for a new area of heart failure treatment. The first clinical trials that target CHIP are already registered.

The Value of Neutrophil-to-Lymphocyte Ratio and Epicardial Adipose Tissue Thickness in Heart Failure With Preserved Ejection Fraction

Background Using epicardial adipose tissue thickness (EATt) and neutrophil-to-lymphocyte ratio (NLR) as individual indicators provides beneficial insight into the prognosis of patients suffering from heart failure with preserved ejection fraction (HFpEF). Aim In our study, we aimed to evaluate whether the combined evaluation of NLR and EATt would provide an advantage for identifying high-risk HFpEF patients according to hospitalization for heart failure (HHF) and left ventricular diastolic dysfunction (LVDD). Method A total of 168 outpatients with HFpEF were retrospectively analyzed. The predictive performance of two inflammatory variables was assessed by the receiver operating characteristic curve and a one-way analysis of variance (ANOVA) test. The patients were stratified into three distinct risk categories based on the established cut-off values for EATt and NLR as follows: Group I, high risk; Group II, middle risk; and Group III, low risk. Results Patients in Group I had the highest risk for HHF and the presence of LVDD (p=0.001 for HHF, p=0.011 for LVDD). Patients in Group I also exhibited more symptomatic and a greater number of comorbidities. In Group I, more structural remodeling (enlarged left ventricular end-systolic volume index (LVESVI) and left atrial volume index (LAVI)) and associated signs of increased intracardiac pressure (elevated E/A ratio, medial E/e') were observed. Conclusion The results of our study indicate that the use of both EATt and NLR among patients with HFpEF may provide better accuracy in predicting HHF and LVDD compared to the use of either EATt or NLR alone.

Inflammation as a therapeutic target in heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) accounts for around half of all cases of heart failure and may become the dominant type of heart failure in the near future. Unlike HF with reduced ejection fraction there are few evidence-based treatment strategies available. There is a significant unmet need for new strategies to improve clinical outcomes in HFpEF patients. Inflammation is widely thought to play a key role in HFpEF pathophysiology and may represent a viable treatment target. In this review focusing predominantly on clinical studies, we will summarise the role of inflammation in HFpEF and discuss potential therapeutic strategies targeting inflammation.

Geriatric Nutritional Risk Index at Hospital Admission or Discharge in Patients with Acute Decompensated Heart Failure

Geriatric Nutritional Risk Index (GNRI) is known both as a reliable indicator of nutritional status and a predictor of long-term survival among patients with acute decompensated heart failure (ADHF). However, the optimal timing to evaluate GNRI during hospitalization remains unclear. In the present study, we retrospectively analyzed patients hospitalized with ADHF in the West Tokyo Heart Failure (WET-HF) registry. GNRI was assessed at hospital admission (a-GNRI) and discharge (d-GNRI). Out of 1474 patients included in the present study, 568 (40.1%) and 796 (57.2%) patients had lower GNRI (<92) at hospital admission and discharge, respectively. After the follow-up (median 616 days), 290 patients died. The multivariable analysis showed that all-cause mortality was independently associated with d-GNRI (per 1 unit decrease, adjusted hazard ratio [aHR]: 1.06, 95% confidence interval [CI]: 1.04-1.09, p < 0.001), but not with a-GNRI (aHR: 0.99, 95% CI: 0.97-1.01, p = 0.341). The predictability of GNRI for long-term survival was more pronounced when evaluated at hospital discharge than at hospital admission (area under the curve 0.699 vs. 0.629, DeLong's test p < 0.001). Our study suggested that GNRI should be evaluated at hospital discharge, regardless of the assessment at hospital admission, to predict the long-term prognosis for patients hospitalized with ADHF.

Periplocin Alleviates Cardiac Remodeling in DOCA-Salt-Induced Heart Failure Rats

Heart failure with preserved ejection fraction (HFpEF) is a common public health problem associated with increased morbidity and long-term mortality. However, effective treatment for HFpEF was not discovered yet. In the present study, we aimed to decipher the effects of Periplocin on DOCA-induced heart failure rats and explore the possible underlying mechanisms. We demonstrated that Periplocin could significantly attenuate cardiac structural remodeling and improve cardiac diastolic function. Of note, Periplocin significantly inhibited the recruitment of inflammatory and immune cells and decreased the expression of serum inflammatory cytokines. Meanwhile, Periplocin had the effect of cardiac glycosides to improve cardiomyocyte contractility and calcium transient amplitude. These findings indicate that Periplocin might be a potential medicine to treat HFpEF in patients.

Predictive value of serum irisin for chronic heart failure in patients with type 2 diabetes mellitus

We hypothesize that serum irisin can have additional discriminative potency for heart failure (HF) in individuals with type 2 diabetes mellitus (T2DM). The study group comprised 226 consecutive T2DM patients (153 patients with any HF phenotypes and 30 patients without HF) aged 41 to 65 years. The plasma levels N-terminal brain natriuretic pro-peptide (NT-proBNP) and irisin were detected by ELISA at the baseline of the study. We found that the most appropriate cut-off value of irisin (HF versus non-HF) were 10.4 ng/mL (area under curve [AUC] = 0.96, sensitivity = 81.0%, specificity = 88.0%; P = 0.0001). Cutoff point of NT-proBNP that distinguished patients with HF and without it was 750 pmol/L (AUC = 0.78; sensitivity = 72.7%, specificity 76.5%, p = 0.0001). Using multivariate comparative analysis we established that concentrations of irisin < 10.4 ng/mL (odds ration [OR] = 1.30; P = 0.001) and NT-proBNP > 750 pmol/mL (OR = 1.17; P = 0.042), left atrial volume index (LAVI) > 34 mL/m² (OR = 1.06; P = 0.042) independently predicted HF. Irisin being added to NT-proBNP improved predictive modality for HF, whereas combination of NT-proBNP and LAVI > 34 mL/m² did not. In conclusion, we established that irisin had independent predicted potency for HF in patients with established T2DM.

Discriminative Value of Serum Irisin in Prediction of Heart Failure with Different Phenotypes among Patients with Type 2 Diabetes Mellitus

Recent studies have shown that circulating levels of irisin are prognostic factors in heart failure (HF), but no data are available on the predictive role of irisin in patients with type 2 diabetes mellitus (T2DM) and different phenotypes of HF. The aim of the study was to investigate whether serum levels of irisin predict HF in T2DM patients. We prospectively included 183 participants with T2DM aged 41 to 62 years (30 non-HF patients and 153 HF patients) and 25 healthy volunteers in the study and evaluated clinical data, hemodynamics and biomarkers (N-terminal pro-brain natriuretic peptide (NT-proBNP) and irisin). Serum levels of irisin < 8.30 ng/mL were found to be a better indicator of HF with reduced ejection fraction (HFrEF) than irisin ≥ 8.30 ng/mL, but the predictive cut-off point for NT-proBNP remained the same as for HF with mildly reduced ejection fraction (HFmrEF). Serum levels of irisin < 10.4 ng/mL significantly improved the predictive ability of NT-proBNP for HF with preserved ejection fraction (HFpEF). In conclusion, we found that decreased serum levels of irisin significantly predicted HFpEF, rather than HFmrEF and HFrEF, in T2DM patients. This finding may open a new approach to HF risk stratification in T2DM patients.

Current Management of Heart Failure with Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) encompasses nearly half of heart failure (HF) worldwide, and still remains a poor prognostic indicator. It commonly coexists in patients with vascular disease and needs to be recognized and managed appropriately to reduce morbidity and mortality. Due to the heterogeneity of HFpEF as a disease process, targeted pharmacotherapy to this date has not shown a survival benefit among this population. This article serves as a comprehensive historical review focusing on the management of HFpEF by reviewing past, present, and future randomized controlled trials that attempt to uncover a therapeutic value. With a paradigm shift in the pathophysiology of HFpEF as an inflammatory, neurohormonal, and interstitial process, a phenotypic approach has increased in popularity focusing on the treatment of HFpEF as a systemic disease. This article also addresses common comorbidities associated with HFpEF as well as current and ongoing clinical trials looking to further elucidate such links.

Heart failure with preserved ejection fraction: key stumbling blocks for experimental drugs in clinical trials

INTRODUCTION

Heart failure with preserved ejection fraction (HFpEF) is a disease process with a high prevalence. Accounting for more than 50% of all heart failure cases, it carries a significant mortality. So far, there has been a lack of therapeutic options that truly show improvement in morbidity and mortality. Certain novel therapies have shown a decrease in heart failure hospitalizations, however, this beneficial effect was more pronounced for heart failure patients with mildly reduced ejection fraction (EF).

AREAS COVERED

This review summarizes the pathophysiology of the disease to help elucidate the differences between heart failure with reduced ejection fraction (HFrEF), and HFpEF, which could explain why therapies are successful in one (rather than the other). At the focus of this review are non-standardized nomenclature across major trials, the challenges of finding a therapeutic agent for such a heterogeneous population, and identification of specific phenotypes that have different outcomes and could be a target for future therapies.

EXPERT OPINION

Lack of standardized diagnostic criteria, associated with population heterogeneity, might explain why trials have failed to improve outcomes for patients with HFpEF. Standardizing phenotypes and recapitulating these phenotypes in animal models, as well as understanding the mechanisms of the disease at the molecular level could be the first steps in identifying promising therapeutic options.

Polymorphic Variants in the GRK5 Gene Promoter Are Associated With Diastolic Dysfunction in Coronary Artery Bypass Graft Surgery Patients

BACKGROUND

The G-protein-coupled receptor kinase 5 (GRK5) is a mediator of cardiovascular homeostasis and participates in inflammation and cardiac fibrosis, both being involved in the development of diastolic dysfunction (DD). While mechanisms of transcriptional regulation of the GRK5 promoter are unclear, we tested the hypotheses, that (1) GRK5 expression varies depending on functional single nucleotide polymorphisms (SNPs) in the GRK5 promoter and (2) this is associated with DD in patients undergoing coronary artery bypass graft (CABG) surgery.

METHODS

We amplified and sequenced the GRK5 promoter followed by cloning, reporter assays, and electrophoretic mobility shift assays (EMSA). GRK5 messenger ribonucleic acid (mRNA) expression was determined in right atrial tissue sampled from 50 patients undergoing CABG surgery. In another prospective study, GRK5 genotypes were associated with determinants of diastolic function using transesophageal echocardiography in 255 patients with CABG with normal systolic left ventricular (LV) function. Specifically, we measured ejection fraction (EF), transmitral Doppler early filling velocity (E), tissue Doppler early diastolic lateral mitral annular velocity (E' lateral), and calculated E/E', E' norm and the difference of E' lateral and E' norm to account for age-related changes in diastolic function.

RESULTS

We identified 6 SNPs creating 3 novel haplotypes with the greatest promoter activation in haplotype tagging (ht) SNP T(-678)C T-allele constructs (P < .001). EMSAs showed allele-specific transcription factor binding proving functional activity. GRK5 mRNA expression was greatest in TT genotypes (TT: 131 fg/µg [95% CI, 108-154]; CT: 109 [95% confidence interval {CI}, 93-124]; CC: 83 [95% CI, 54-112]; P = .012). Moreover, GRK5 genotypes were significantly associated with determinants of diastolic function. Grading of DD revealed more grade 3 patients in TT compared to CT and CC genotypes (58% vs 38% vs 4%; P = .023). E´ lateral was lowest in TT genotypes (P = .007) and corresponding E/E' measurements showed 1.27-fold increased values in TT versus CC genotypes (P = .01), respectively. While E' norm values were not different between genotypes (P = .182), the difference between E' lateral and E' norm was significantly higher in TT genotypes compared to CC and CT genotypes (-1.2 [interquartile range {IQR}, 2.7], -0.5 [IQR, 3.4], and -0.4 [IQR, 4.2; P = .035], respectively).

CONCLUSIONS

A functional GRK5 SNP results in allele-dependent differences in GRK5 promoter activity and mRNA expression. This is associated with altered echocardiographic determinants of diastolic function. Thus, SNPs in the GRK5 promoter are associated with altered perioperative diastolic cardiac function. In the future, preoperative testing for these and other SNPs might allow to initiate more specific diagnostic and perioperative pathways to benefit patients at risk.

Clinical assessment of endothelial function in heart failure with preserved ejection fraction: A meta-analysis with meta-regressions

BACKGROUND

Endothelial dysfunction is a key mechanism in the development of cardiac remodelling and diastolic dysfunction in heart failure with preserved ejection fraction (HFpEF). Flow-mediated (FMD) and nitrate-mediated dilation (NMD) are noninvasive methods to assess endothelial function. We performed a meta-analysis evaluating the impact of HFpEF on FMD and NMD.

METHODS

PubMed, Web of Science, Scopus and EMBASE databases were systematically searched according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Differences were expressed as mean difference (MD) with 95% confidence intervals (95%CI). The random effects method was used.

RESULTS

A total of seven studies were included in the final analysis, 7 with data on FMD (326 HFpEF patients and 417 controls) and 3 on NMD (185 HFpEF patients and 271 controls). Compared to controls, HFpEF patients showed significantly lower FMD (MD: -1.929; 95%CI: -2.770, -1.088; P < .0001) and NMD values (MD: -2.795; 95%CI: -3.876, -1.715; P < .0001). Sensitivity analyses substantially confirmed results. Meta-regression models showed that increasing differences in E/A ratio (Z-score: -2.002; P = .045), E/E' ratio (Z-score: -2.181; P = .029) and left atrial diameter (Z-score: -1.951; P = .050) were linked to higher differences in FMD values between cases and controls.

CONCLUSIONS

Impaired endothelial function can be documented in HFpEF, with the possibility of a direct association between the severity of diastolic and endothelial dysfunction. Targeting endothelial dysfunction through pharmacological and rehabilitation strategies may represent an attractive therapeutic option.

Mitochondrial function, dynamics and quality control in the pathophysiology of HFpEF

Heart failure (HF) is one of the leading causes of hospitalization for the adult population and a major cause of mortality worldwide. The HF syndrome is characterized by the heart's inability to supply the cardiac output required to meet the body's metabolic requirements or only at the expense of elevated filling pressures. HF without overt impairment of left ventricular ejection fraction (LVEF) was initially labeled as "diastolic HF" until recognizing the coexistence of both systolic and diastolic abnormalities in most cases. Acknowledging these findings, the preferred nomenclature is HF with preserved EF (HFpEF). This syndrome primarily affects the elderly population and is associated with a heterogeneous overlapping of comorbidities that makes its diagnosis challenging. Despite extensive research, there is still no evidence-based therapy for HFpEF, reinforcing the need for a thorough understanding of the pathophysiology underlying its onset and progression. The role of mitochondrial dysfunction in developing the pathophysiological changes that accompany HFpEF onset and progression (low-grade systemic inflammation, oxidative stress, endothelial dysfunction, and myocardial remodeling) has just begun to be acknowledged. This review summarizes our current understanding of the participation of the mitochondrial network in the pathogenesis of HFpEF, with particular emphasis on the signaling pathways involved, which may provide future therapeutic targets.

Resveratrol Ameliorates Cardiac Remodeling in a Murine Model of Heart Failure With Preserved Ejection Fraction

Objective: Accumulating evidence suggested that resveratrol (RES) could protect against adverse cardiac remodeling induced by several cardiovascular diseases. However, the role of RES in the setting of heart failure with preserved ejection fraction (HFpEF) and the underlying mechanisms of its action remain understood. This study was to determine whether RES could ameliorate HFpEF-induced cardiac remodeling and its mechanisms.

Methods:In vivo, C57BL/6 mice served as either the sham or the HFpEF model. The HFpEF mice model was induced by uninephrectomy surgery and d-aldosterone infusion. RES (10 mg/kg/day, ig) or saline was administered to the mice for four weeks. In vitro, transforming growth factor β1 (TGF-β1) was used to stimulate neonatal rat cardiac fibroblasts (CFs) and Ex-527 was used to inhibit sirtuin 1 (Sirt1) in CFs. Echocardiography, hemodynamics, western blotting, quantitative real-time PCR, histological analysis, immunofluorescence, and ELISA kits were used to evaluate cardiac remodeling induced by HFpEF. Sirt1 and Smad3 expressions were measured to explore the underlying mechanisms of RES.

Results: HFpEF mice developed left ventricular hypertrophy, preserved ejection fraction, diastolic dysfunction, and pulmonary congestion. Moreover, HFpEF mice showed increased infiltration of neutrophils and macrophages into the heart, including increased interleukin (IL)-1β, IL-6, and TNF-α. We also observed elevated M1 macrophages and decreased M2 macrophages, which were exhibited by increased mRNA expression of M1 markers (iNOS, CD86, and CD80) and decreased mRNA expression of M2 markers (Arg1, CD163, and CD206) in HFpEF hearts. Moreover, HFpEF hearts showed increased levels of intracellular reactive oxygen species (ROS). Importantly, HFpEF mice depicted increased collagen-I and -III and TGF-β mRNA expressions and decreased protein expression of phosphorylated endothelial nitric-oxide synthase (p-eNOS). Results of western blot revealed that the activated TGF-β/Smad3 signaling pathway mediated HFpEF-induced cardiac remodeling. As expected, this HFpEF-induced cardiac remodeling was reversed when treated with RES. RES significantly decreased Smad3 acetylation and inhibited Smad3 transcriptional activity induced by HFpEF via activating Sirt1. Inhibited Sirt1 with Ex-527 increased Smad3 acetylation, enhanced Smad3 transcriptional activity, and offset the protective effect of RES on TGF-β–induced cardiac fibroblast–myofibroblast transformation in CFs.

Conclusion: Our results suggested that RES exerts a protective action against HFpEF-induced adverse cardiac remodeling by decreasing Smad3 acetylation and transcriptional activity via activating Sirt1. RES is expected to be a novel therapy option for HFpEF patients.

Therapeutic Stalemate in Heart Failure With Preserved Ejection Fraction

The findings of randomized trials of neurohormonal modulation have been neutral in heart failure with preserved ejection fraction and consistently positive in heart failure with reduced ejection. Left ventricular remodeling promotes the development and progression of heart failure with preserved and reduced ejection fraction. However, different stimuli mediate left ventricular remodeling that is commonly concentric in heart failure with preserved ejection fraction and eccentric in heart failure with reduced ejection. The stimuli that promote concentric left ventricular remodeling may account for the neutral findings of neuhormonal modulation in heart failure with preserved ejection fraction. Low‐grade systemic inflammation‐induced microvascular endothelial dysfunction is currently the leading hypothesis behind the development and progression of heart failure with preserved ejection fraction. The hypothesis provided the rationale for several randomized controlled trials that have led to neutral findings. The trials and their limitations are reviewed.

Immunomodulation in Heart Failure with Preserved Ejection Fraction: Current State and Future Perspectives

The heart failure (HF) epidemic is growing and approximately half of the HF patients have heart failure with preserved ejection fraction (HFpEF). HFpEF is a heterogeneous syndrome, characterized by a preserved left ventricular ejection fraction (LVEF ≥ 50%) with diastolic dysfunction, and is associated with high morbidity and mortality. Underlying comorbidities of HFpEF, i.e., hypertension, type 2 diabetes mellitus, obesity, and renal failure, lead to a systemic pro-inflammatory state, thereby affecting normal cardiac function. Increased inflammatory biomarkers predict incident HFpEF and are higher in patients with HFpEF as compared with heart failure with reduced ejection fraction (HFrEF). Randomized trials in HFpEF patients using traditional HF medication failed to demonstrate a clear benefit on hard endpoints (mortality and/or HF hospitalization). Therefore, therapies targeting underlying comorbidities and systemic inflammation in early HFpEF may provide better opportunities. Here, we provide an overview of the current state and future perspectives of immunomodulatory therapies for HFpEF.

Mechanisms underlying the pathophysiology of heart failure with preserved ejection fraction: the tip of the iceberg

Heart failure with preserved ejection fraction (HFpEF) is a multifaceted syndrome with a complex aetiology often associated with several comorbidities, such as left ventricle pressure overload, diabetes mellitus, obesity, and kidney disease. Its pathophysiology remains obscure mainly due to the complex phenotype induced by all these associated comorbidities and to the scarcity of animal models that adequately mimic HFpEF. Increased oxidative stress, inflammation, and endothelial dysfunction are currently accepted as key players in HFpEF pathophysiology. However, we have just started to unveil HFpEF complexity and the role of calcium handling, energetic metabolism, and mitochondrial function remain to clarify. Indeed, the enlightenment of such cellular and molecular mechanisms represents an opportunity to develop novel therapeutic approaches and thus to improve HFpEF treatment options. In the last decades, the number of research groups dedicated to studying HFpEF has increased, denoting the importance and the magnitude achieved by this syndrome. In the current technological and web world, the amount of information is overwhelming, driving us not only to compile the most relevant information about the theme but also to explore beyond the tip of the iceberg. Thus, this review aims to encompass the most recent knowledge related to HFpEF or HFpEF-associated comorbidities, focusing mainly on myocardial metabolism, oxidative stress, and energetic pathways.

Protective Effects of a Discontinuous Treatment with Alpha-Lipoic Acid in Obesity-Related Heart Failure with Preserved Ejection Fraction, in Rats

Obesity induces hemodynamic and humoral changes that are associated with functional and structural cardiac remodeling, which ultimately result in the development of heart failure (HF) with preserved ejection fraction (HFpEF). In recent years, pharmacological studies in patients with HFpEF were mostly unsatisfactory. In these conditions, alternative new therapeutic approaches are necessary. The aim of our study was (1) to assess the effects of obesity on heart function in an experimental model and (2) to evaluate the efficacy of an alpha-lipoic acid (ALA) antioxidant treatment. Sprague-Dawley rats (7 weeks old) were either included in the control group (n = 6) or subjected to abdominal aortic banding (AAB) and divided into three subgroups, depending on their diet: standard (AAB + SD, n = 8), hypecaloric (AAB + HD, n = 8) and hypecaloric with discontinuous ALA treatment (AAB + HD + ALA, n = 9). Body weight (BW), glycemia, echocardiography parameters and plasma hydroperoxides were monitored throughout the study. After 36 weeks, plasma adiposity (leptin and adiponectin) and inflammation (IL-6 and TNF-alpha) markers, together with B-type natriuretic peptide and oxidative stress markers (end-products of lipid peroxidation and endogenous antioxidant systems) were assessed. Moreover, cardiac fiber diameters were measured. In our experiment, diet-induced obesity generated cardiometabolic disturbances, and in association with pressure-overload induced by AAB, it precipitated the onset of heart failure, cardiac hypertrophy and diastolic dysfunction, while producing a pro-oxidant and pro-inflammatory plasmatic status. In relationship with its antioxidant effects, the chronic ALA-discontinuous treatment prevented BW gain and decreased metabolic and cardiac perturbations, confirming its protective effects on the cardiovascular system.

Proteomic Evaluation of the Comorbidity-Inflammation Paradigm in Heart Failure With Preserved Ejection Fraction: Results From the PROMIS-HFpEF Study

BACKGROUND

A systemic proinflammatory state has been hypothesized to mediate the association between comorbidities and abnormal cardiac structure/function in heart failure with preserved ejection fraction (HFpEF). We conducted a proteomic analysis to investigate this paradigm.

METHODS

In 228 patients with HFpEF from the multicenter PROMIS-HFpEF study (Prevalence of Microvascular Dysfunction in Heart Failure With Preserved Ejection Fraction), 248 unique circulating proteins were quantified by a multiplex immunoassay (Olink) and used to recapitulate systemic inflammation. In a deductive approach, we performed principal component analysis to summarize 47 proteins known a priori to be involved in inflammation. In an inductive approach, we performed unbiased weighted coexpression network analyses of all 248 proteins to identify clusters of proteins that overrepresented inflammatory pathways. We defined comorbidity burden as the sum of 8 common HFpEF comorbidities. We used multivariable linear regression and statistical mediation analyses to determine whether and to what extent inflammation mediates the association of comorbidity burden with abnormal cardiac structure/function in HFpEF. We also externally validated our findings in an independent cohort of 117 HFpEF cases and 30 comorbidity controls without heart failure.

RESULTS

Comorbidity burden was associated with abnormal cardiac structure/function and with principal components/clusters of inflammation proteins. Systemic inflammation was also associated with increased mitral E velocity, E/e' ratio, and tricuspid regurgitation velocity; and worse right ventricular function (tricuspid annular plane systolic excursion and right ventricular free wall strain). Inflammation mediated the association between comorbidity burden and mitral E velocity (proportion mediated 19%-35%), E/e' ratio (18%-29%), tricuspid regurgitation velocity (27%-41%), and tricuspid annular plane systolic excursion (13%) (P<0.05 for all), but not right ventricular free wall strain. TNFR1 (tumor necrosis factor receptor 1), UPAR (urokinase plasminogen activator receptor), IGFBP7 (insulin-like growth factor binding protein 7), and GDF-15 (growth differentiation factor-15) were the top individual proteins that mediated the relationship between comorbidity burden and echocardiographic parameters. In the validation cohort, inflammation was upregulated in HFpEF cases versus controls, and the most prominent inflammation protein cluster identified in PROMIS-HFpEF was also present in HFpEF cases (but not controls) in the validation cohort.

CONCLUSIONS

Proteins involved in inflammation form a conserved network in HFpEF across 2 independent cohorts and may mediate the association between comorbidity burden and echocardiographic indicators of worse hemodynamics and right ventricular dysfunction. These findings support the comorbidity-inflammation paradigm in HFpEF.

Heart Failure with Preserved Ejection Fraction-a Concise Review

Purpose of Review

Heart failure with preserved ejection fraction (HFpEF) is a relatively new disease entity used in medical terminology; however, both the number of patients and its clinical significance are growing. HFpEF used to be seen as a mild condition; however, the symptoms and quality of life of the patients are comparable to those with reduced ejection fraction. The disease is much more complex than previously thought. In this article, information surrounding the etiology, diagnosis, prognosis, and possible therapeutic options of HFpEF are reviewed and summarized.

Recent Findings

It has recently been proposed that heart failure (HF) is rather a heterogeneous syndrome with a spectrum of overlapping and distinct characteristics. HFpEF itself can be distilled into different phenotypes based on the underlying biology. The etiological factors of HFpEF are unclear; however, systemic low-grade inflammation and microvascular damage as a consequence of comorbidities associated with endothelial dysfunction, oxidative stress, myocardial remodeling, and fibrosis are considered to play a crucial role in the pathogenesis of a disease. The H₂FPEF score and the HFpEF nomogram are recently validated highly sensitive tools employed for risk assessment of subclinical heart failure.

Summary

Despite numerous studies, there is still no evidence-based pharmacotherapy for HFpEF and the mortality and morbidity associated with HFpEF remain high. A better understanding of the etiological factors, the impact of comorbidities, the phenotypes of the disease, and implementation of machine learning algorithms may play a key role in the development of future therapeutic strategies.

Leucocyte count predicts cardiovascular risk in heart failure with preserved ejection fraction: insights from TOPCAT Americas

AIMS

Prior evidence has implicated leucocyte expansion in several cardiovascular disorders, including heart failure (HF) with reduced ejection fraction (rEF). However, the prognostic importance of leucocyte count in HF with preserved EF (HFpEF) remains largely unexplored.

METHODS AND RESULTS

The Americas cohort of the treatment of preserved cardiac function heart failure with an aldosterone antagonist (TOPCAT-Americas) was used to evaluate the association between total leucocyte count and clinical outcomes in HFpEF. The primary outcome was a composite of aborted cardiac arrest, cardiovascular mortality, or hospitalization for HF. Secondary outcomes were hospitalization for HF, aborted cardiac arrest, stroke, non-fatal myocardial infarction (MI), cardiovascular mortality, non-cardiovascular mortality, and all-cause mortality. Survival models were used to identify the risk of the primary and secondary outcomes in those with leucocyte count above the median (7100 cells/μL), as compared to those with leucocyte count below the median, during the follow-up period. A total of 1746 (out of 1767; 99%) patients from TOPCAT-Americas were available for the analyses with a median follow up of 2.4 (25th to 75th percentile 1.4-3.9) years. Patients with leucocyte count >7100 cells/μL were 36% more likely to experience the primary endpoint compared to those with ≤7100 cells/μL (hazard ratio: 1.36, 95% confidence interval: 1.14-1.61). This association remained significant after extensive adjustment for potential confounders (hazard ratio: 1.27, 95% confidence interval: 1.06-1.52). We also observed a greater incidence of HF hospitalization and non-fatal MI in patients with higher leucocyte count. These associations remained robust on sensitivity analyses, suggesting a low probability of confounding. Exploratory analyses suggested that both higher leucocyte count (integrating the combined influence of both myeloid and lymphoid immune cells) and augmented platelet count (as a surrogate for myeloid immune cell expansion) in the same model were associated with the primary outcome (both P < 0.05).

CONCLUSIONS

Leucocyte count >7100 cells/μL was independently associated with adverse clinical outcomes in HFpEF patients from TOPCAT-Americas. These results were primarily driven by the HF hospitalization outcome but were also accompanied by an excess of non-fatal MI. Further research is needed to define the mechanisms underlying our findings and their prognostic implications.

Value of Neutrophil to Lymphocyte Ratio and Its Trajectory in Patients Hospitalized With Acute Heart Failure and Preserved Ejection Fraction

The neutrophil to lymphocyte ratio (NLR) has been proposed as a simple and routinely obtained marker of inflammation. This study sought to determine whether the NLR on admission as well as NLR trajectory would be complementary to the Get with the Guidelines Heart Failure (GWTG-HF) risk score in patients hospitalized with acute heart failure with preserved ejection fraction (HFpEF).Using the Stanford Translational Research Database, we identified 443 patients between January 2002 and December 2013 hospitalized with acute HFpEF and with complete data of NLR both on admission and at discharge. The primary endpoint was all-cause mortality. Mean age was 77 ± 16 years, 58% were female, with a high prevalence of diabetes mellitus (35.4%), coronary artery disease (58.2%), systemic hypertension (96.6%) and history of atrial fibrillation (57.5%). Over a median follow-up of 2.2 years, 121 (27.3%) patients died. The median NLR on admission was 6.5 (IQR 3.6 - 11.1); a majority of patients decreased their NLR during the course of hospitalization. On multivariable Cox modeling, both NLR on admission (HR 1.18 95% CI (1.00 - .38), p = 0.04) and absolute NLR trajectory (HR 1.26 95% CI (1.10 - 1.45), p = 0.001) were shown to be incremental to GWTG-HF risk score (p < 0.05) for outcome prediction. Adding the NLR or absolute NLR trajectory to the GWTG-HF risk score significantly improved the area under the operator-receiver curve and the reclassification up to 3 years after admission.This simple, readily available marker of inflammation may be useful when stratifying the risk of patients hospitalized with HFpEF.

Neuroinflammation in heart failure: new insights for an old disease

Heart failure (HF) is a complex clinical syndrome affecting roughly 26 million people worldwide. Increased sympathetic drive is a hallmark of HF and is associated with disease progression and higher mortality risk. Several mechanisms contribute to enhanced sympathetic activity in HF, but these pathways are still incompletely understood. Previous work suggests that inflammation and activation of the renin-angiotensin system (RAS) increases sympathetic drive. Importantly, chronic inflammation in several brain regions is commonly observed in aged populations, and a growing body of evidence suggests neuroinflammation plays a crucial role in HF. In animal models of HF, central inhibition of RAS and pro-inflammatory cytokines normalizes sympathetic drive and improves cardiac function. The precise molecular and cellular mechanisms that lead to neuroinflammation and its effect on HF progression remain undetermined. This review summarizes the most recent advances in the field of neuroinflammation and autonomic control in HF. In addition, it focuses on cellular and molecular mediators of neuroinflammation in HF and in particular on brain regions involved in sympathetic control. Finally, we will comment on what is known about neuroinflammation in the context of preserved vs. reduced ejection fraction HF.

Xiao-Qing-Long Tang Prevents Cardiomyocyte Hypertrophy, Fibrosis, and the Development of Heart Failure with Preserved Ejection Faction in Rats by Modulating the Composition of the Gut Microbiota

Background

Changes in the gut microbiota are associated with cardiovascular disease progression. Xiao-Qing-Long Tang (XQLT), a traditional herbal formula, has an anti-inflammatory effect and regulates the steady state of the immune system, which is also associated with the progression of heart failure with preserved ejection faction (HFpEF). In this study, we investigated whether XQLT could contribute to prevent the development of HFpEF and whether the modulation of the gut microbiota by this herbal formula could be involved in such effect.

Methods

The gut microbiota, SCFAs, the histology/function of the heart, and systolic blood pressure were examined to evaluate the effect of XQLT on the gut microbiota and the progression of HFpEF after oral administration of XQLT to model rats. Furthermore, we evaluated, through fecal microbiota transplantation experiments, whether the favorable effects of XQLT could be mediated by the gut microbiota.

Results

Oral administration of XQLT contributed to the reduction of elevated blood pressure, inflammation, and compensatory hypertrophy, features that are associated with the progression of HFpEF. The gut microbiota composition, SCFA levels, and intestinal mucosal histology were improved after treatment with XQLT. Moreover, fecal transfer from XQLT-treated rats was sufficient to prevent the progression of HFpEF.

Conclusions

These data suggested that XQLT prevented the development of HFpEF in model rats by regulating the composition of the gut microbiota.

ALDH2 rs671 polymorphism and the risk of heart failure with preserved ejection fraction (HFpEF) in patients with cardiovascular diseases

Aldehyde dehydrogenase 2 (ALDH2) rs671 polymorphism is an established genetic risk of hypertension, diabetes, and coronary heart diseases in Asian population. Previous experimental data showed ALDH2 regulated inflammation, a potential mechanism of heart failure with preserved ejection fraction (HFpEF). However, clinically, the association between ALDH2 polymorphism and incidence of HFpEF remains unknown. In this prospective cross-sectional study, ALDH2 genotyping was performed in 613 consecutive patients enrolled with cardiovascular diseases (CVDs), including hypertension, coronary heart diseases, and/or diabetes mellitus, with normal left ventricular ejection fraction (LVEF). HFpEF was diagnosed according to symptoms and/or signs of dyspnea, fatigue or ankle swelling, N-terminal pro-B-Type natriuretic peptide (NT pro-BNP ≥ 280 pg/mL), LVEF ≥ 50%, and at least one additional criterion: left atrial enlargement (left atrial diameter > 40 mm), diastolic dysfunction (E/E' ≥ 13 or E'/A' < 1) or concurrently with atrial fibrillation. Finally, of 613 patients with CVD, 379 patients (61.8%) were assigned to the wild-type ALDH2*1/*1 group and 234 patients (38.2%) to the mutation-type ALDH2*2 group according to genotyping results. Sixty-nine patients (11.3%) were diagnosed with HFpEF. In ALDH2*2 group, the occurrence of HFpEF was higher (15.4% vs. 8.7%, p = 0.011) than that in ALDH2*1/*1 group. Leukocyte count, the indicator of systemic inflammation, was significantly higher (6.9 ± 2.4 × 10⁹/L vs. 6.5 ± 1.9 × 10⁹/L, p = 0.010) in ALDH2*2 group compared to ALDH2*1/*1 group. In conclusion, ALDH2*2 variant is associated with the risk of HFpEF in patients with CVD. Increased systemic inflammation probably involved in this disease process.

Effect of aerobic and resistance training on inflammatory markers in heart failure patients: systematic review and meta-analysis

Elevated levels of pro-inflammatory markers are evident in patients with heart failure and are associated with disease severity and prognosis. Exercise training has been shown to reduce circulating levels of pro-inflammatory cytokines and other pro-inflammatory markers in healthy and clinical populations. The aim of the systematic review and meta-analysis was to investigate the effect of aerobic (AT) and resistance training (RT) interventions on circulating concentrations of inflammatory markers; tumour necrosis factor-alpha (TNF-α), interleukin 6 (IL-6), C-reactive protein (CRP), fibrinogen, soluble intercellular adhesion molecule (sICAM) and soluble vascular adhesion molecule (sVCAM) in heart failure patients. We conducted database searches (PubMed, EMBASE and Cochrane Trials Register to 30 June 2017) for exercise-based trials in heart failure, using the following search terms: exercise training, inflammation, tumour necrosis factor-alpha, interleukin 6, C-reactive protein, fibrinogen, soluble intercellular adhesions molecule-1, soluble vascular adhesion molecule-1. Twenty studies, representing 18 independent trials, were included in the review. Pooled data of six studies indicated a minimally favourable effect of exercise training on circulating TNF-α [SMD 0.42 (95% CI 0.15, 0.68), p = 0.002)]. However, together the pooled and descriptive analyses failed to provide strong evidence for a reduction in other pro-inflammatory markers. However, given the complexity of heart failure and the pathways involved in the immune and inflammatory process, large prospective trials considering aetiology, comorbidities and local skeletal muscle inflammation are required to elucidate on the anti-inflammatory effect of exercise in this population.

The Inflammatory Response to Ventricular Assist Devices

The therapeutic use of ventricular assist devices (VADs) for end-stage heart failure (HF) patients who are ineligible for transplant has increased steadily in the last decade. In parallel, improvements in VAD design have reduced device size, cost, and device-related complications. These complications include infection and thrombosis which share underpinning contribution from the inflammatory response and remain common risks from VAD implantation. An added and underappreciated difficulty in designing a VAD that supports heart function and aids the repair of damaged myocardium is that different types of HF are accompanied by different inflammatory profiles that can affect the response to the implanted device. Circulating inflammatory markers and changes in leukocyte phenotypes receive much attention as biomarkers for mortality and disease progression. However, they are seldom used to monitor progress during and outcomes from VAD therapy or during the design phase for new devices. Even the partial reversal of heart damage associated with heart failure is a desirable outcome from VAD use. Therefore, improved understanding of the interplay between VADs and the recipient's inflammatory response would potentially increase their uptake, improve patient lives, and fuel research related to other blood-contacting medical devices. Here we provide a review of what is currently known about inflammation in heart failure and how this inflammatory profile is altered in heart failure patients receiving VAD therapy.

Skeletal Muscle Myopathy in Heart Failure: the Role of Ejection Fraction

PURPOSE OF REVIEW

This review summarizes: (1) the structural and functional features coupled with pathophysiological factors responsible of skeletal muscle myopathy (SMM) in both heart failure with reduced (HFrEF) and preserved (HFpEF) ejection fraction and (2) the role of exercise as treatment of SMM in these HF-related phenotypes.

RECENT FINDINGS

The recent literature showed two main phenotypes of heart failure (HF): (1) HFrEF primarily due to a systolic dysfunction of the left ventricle and (2) HFpEF, mainly related to a diastolic dysfunction. Exercise intolerance is one of most disabling symptoms of HF and it is shown that persists after the normalization of the central hemodynamic impairments by therapy and/or cardiac surgery including heart transplant. A specific skeletal muscle myopathy (SMM) has been defined as one of the main causes of exercise intolerance in HF. The SMM has been well described in the last 20 years in the HFrEF; on the contrary, few studies are available in HFpEF. Recent evidences have revealed that exercise training counteracts HF-related SMM and in turn ameliorates exercise intolerance.

Cilostazol ameliorates heart failure with preserved ejection fraction and diastolic dysfunction in obese and non-obese hypertensive mice

Cilostazol (Ciloz) a potent Type III phosphodiesterase inhibitor is effective against inflammation, insulin resistance and cardiomyopathy. However, the effect of Ciloz on obesity-associated left ventricular diastolic dysfunction has not been explored yet. Hence, we examined the effect of Ciloz on cardiac remodelling and dysfunction in non-obese and obese-insulin resistant mice infused with AngiotensinII (AngII). Male C57BL/6 J mice were initially subjected to 19 weeks of chow or high fat diet (HFD) regimen and thereafter animals were randomised for AngII (1500 ng/kg/min, s.c) infusion or saline and Ciloz (50 mg/kg, p.o) for another 1 week. Obese and non-obese mice infused with AngII exhibited significant diastolic dysfunction and features of heart failure with preserved ejection fraction (HFpEF) since a decrease in fractional shortening and no change in ejection fraction were observed when compared with respective controls. Administration of AngII and Ciloz in HFD fed mice significantly improved the left ventricular function compared with AngII infused HFD mice as evinced from the echocardiographic data. Further, Ciloz treatment significantly reduced cardiomyocyte area, interstitial and perivascular fibrosis; and collagen deposition. Moreover, Ciloz reduced the inflammatory milieu in the heart as evinced by decreased F4/80⁺ and CD68⁺ cells; IL-1β and IL-6 gene transcripts. Quantitative assessment of the expression levels revealed substantial upregulation of MMP-9 (pro- and mature-forms) and α-SMA in the left ventricle of AngII infused HFD-fed mice, which was considerably suppressed by Ciloz regimen. The beneficial effect of Ciloz was associated with the normalization in gene expression of hypertrophic and fibrotic markers. Likewise, Ciloz administration markedly reduced the AngII and HFD induced TGF-β1/SMAD3 and Akt/mTOR signalling. Additionally, AngII administered and HFD-fed mice showed increased glycolytic flux, which was considerably diminished by Ciloz treatment as indicated from suppressed PKM2, HK-2, PDK-2, HIF-1α mRNA and GLUT-1 protein expression. Taken together, Ciloz might be therapeutically exploited against AngII and obesity-associated diastolic dysfunction thereby preventing overt heart failure.

Pro-Inflammatory Biomarkers in Stable Versus Acutely Decompensated Heart Failure With Preserved Ejection Fraction

Background

Underlying inflammation has been increasingly recognized in heart failure with a preserved ejection fraction (HFpEF). In this study we tested the hypothesis that pro‐inflammatory biomarkers are elevated in patients with acutely decompensated HFpEF (AD‐HFpEF) compared with patients with stable HFpEF (S‐HFpEF).

Methods and Results

Using a post hoc analysis the serum biomarkers tumor necrosis factor‐alpha, high‐sensitivity C‐reactive protein interleukin 6 and pentraxin 3 (PTX3) and clinical, demographic, echocardiographic‐Doppler and clinical outcomes data were analyzed in HFpEF patients enrolled in NHLBI Heart Failure Research Network clinical trials which enrolled patients with either AD‐HFpEF or S‐HFpEF. Compared to S‐HFpEF, AD‐HFpEF patients had higher levels of PTX3 (3.08 ng/mL versus 1.27 ng/mL, P<0.0001), interleukin‐6 (4.14 pg/mL versus 1.71 pg/mL, P<0.0001), tumor necrosis factor‐alpha (11.54 pg/mL versus 8.62 pg/mL, P=0.0015), and high‐sensitivity C‐reactive protein (11.90 mg/dL versus 3.42 mg/dL, P<0.0001). Moreover, high‐sensitivity C‐reactive protein, interleukin‐6 and PTX3 levels were significantly higher in AD‐HFpEF compared with S‐HFpEF patients admitted for decompensated HF within the previous year. PTX3 was positively correlated with left atrial volume index (r=0.41, P=0.0017) and left ventricular mass (r=0.26, P=0.0415), while tumor necrosis factor‐alpha was inversely correlated with E/A ratio (r=−0.31, P=0.0395).

Conclusions

Levels of pro‐inflammatory biomarkers are strikingly higher in AD‐HFpEF compared with S‐HFpEF patients. PTX3 and tumor necrosis factor‐alpha are correlated with echocardiographic‐Doppler evidence of diastolic dysfunction. Taken together these data support the concept that a heightened pro‐inflammatory state has a pathophysiologic role in the development of AD‐HFpEF.

Systemic inflammation and functional capacity in elderly heart failure patients

BACKGROUND

Elevated C-reactive protein (CRP) is associated with adverse outcomes in heart failure (HF) patients. Beta-blocker therapy may lower CRP levels.

METHODS AND RESULTS

To assess if the changes of high-sensitivity (hs) CRP levels in HF patients over 12-week titration with beta-blockers correlate with functional capacity, plasma hs-CRP levels were measured in 488 HF patients [72.1 ± 5.31 years, LVEF 40% (33/50)]. Hs-CRP, NT-proBNP and 6-min-walk-test (6MWT) were assessed at baseline and at week 12. Patients were divided based on hs-CRP changes (cut-off > 0.3 mg/dl) into low-low (N = 225), high-high (N = 132), low-high (N = 54), high-low (N = 77) groups. At baseline, median hs-CRP concentration was 0.25 (0.12/0.53) mg/dl, NT-proBNP 551 (235/1455) pg/ml and average 6MWT distance 334 ± 105 m. NT-proBNP changes were significantly different between the four hs-CRP groups (P = 0.011). NT-proBNP increased in the low-high group by 30 (- 14/88) pg/ml and decreased in the high-low group by - 8 (- 42/32) pg/ml. 6MWT changes significantly differed between groups [P = 0.002; decrease in the low-high group (- 18 ± 90 m) and improvement in the low-low group (24 ± 62 m)].

CONCLUSION

After beta-blocker treatment, hs-CRP levels are associated with functional capacity in HF patients. Whether this represents a potential target for intervention needs further study.

Exercise training improves cardiac autonomic control, cardiac function, and arrhythmogenesis in rats with preserved-ejection fraction heart failure

Chronic heart failure is characterized by autonomic imbalance, cardiac dysfunction, and arrhythmogenesis. It has been shown that exercise training (ExT) improves central nervous system oxidative stress, autonomic control, and cardiac function in heart failure with reduced ejection fraction; however, to date no comprehensive studies have addressed the effects of ExT, if any, on oxidative stress in brain stem cardiovascular areas, cardiac autonomic balance, arrhythmogenesis, and cardiac function in heart failure with preserved ejection fraction (HFpEF). We hypothesize that ExT reduces brain stem oxidative stress, improves cardiac autonomic control and cardiac function, and reduces arrhythmogenesis in HFpEF rats. Rats underwent sham treatment or volume overload to induce HFpEF. ExT (60 min/day, 25 m/min, 10% inclination) was performed for 6 wk starting at the second week after HFpEF induction. Rats were randomly allocated into Sham+sedentary (Sed) ( n = 8), Sham+ExT ( n = 6), HFpEF+Sed ( n = 8), and HFpEF+ExT ( n = 8) groups. Compared with the HFpEF+Sed condition, HFpEF+ExT rats displayed reduced NAD(P)H oxidase activity and oxidative stress in the rostral ventrolateral medulla (RVLM), improved cardiac autonomic balance, and reduced arrhythmogenesis. Furthermore, a threefold improvement in cardiac function was observed in HFpEF+ExT rats. These novel findings suggest that moderate-intensity ExT is an effective means to attenuate the progression of HFpEF through improvement in RVLM redox state, cardiac autonomic control, and cardiac function.

NEW & NOTEWORTHY In the present study, we found that exercise reduced oxidative stress in key brain stem areas related to autonomic control, improved sympathovagal control of the heart, reduced cardiac arrhythmias, and delayed deterioration of cardiac function in rats with heart failure with preserved ejection fraction (HFpEF). Our results provide strong evidence for the therapeutic efficacy of exercise training in HFpEF.

Five-year changes in cardiac structure and function in patients with rheumatoid arthritis compared with the general population

BACKGROUND

Patients with rheumatoid arthritis (RA) have increased risk of heart failure with preserved ejection fraction. The development and progression of left ventricular dysfunction before onset of clinical heart failure are unknown. The objective of this study was to evaluate longitudinal changes in cardiac structure and function of patients with RA compared with persons in the general population.

METHODS

A prospective longitudinal study of a population-based cohort of 160 patients with RA and a population-based cohort of 1391 persons without RA (non-RA cohort) was performed. Each participant underwent 2-dimensional, pulsed-wave tissue Doppler echocardiography at baseline and after 4 to 5years of follow-up. Age- and sex-adjusted linear regression models were used to test for differences between the RA and non-RA cohorts in annualized rates of change for echocardiographic parameters.

RESULTS

Mitral A velocity increased more rapidly among the patients with RA than the non-RA cohort (age- and sex-adjusted parameter estimate, 0.030; P<0.001). Correspondingly, the mean mitral inflow E/A ratio decreased faster in the RA cohort than the non-RA cohort (adjusted parameter estimate, -0.096; P<0.001). The left atrial volume index increased at a higher rate in the RA cohort than the non-RA cohort (adjusted parameter estimate, 0.150; P<0.001).

CONCLUSIONS

This pattern of echocardiographic findings confirms previous cross-sectional studies and indicates that subclinical changes in diastolic function occur more rapidly over 5years in RA patients than in the general population. Further research into the mechanisms of myocardial disease in these patients and the relationship with disease activity and treatment is warranted.

Follistatin like 1 Regulates Hypertrophy in Heart Failure with Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) accounts for ∼50% of all clinical presentations of heart failure, (HF) and its prevalence is expected to increase. However, there are no evidence-based therapies for HFpEF; thus, HFpEF represents a major unmet need. Although hypertension is the single most important risk factor for HFpEF, with a prevalence of 60% to 89% from clinical trials and human HF registries, blood pressure therapy alone is insufficient to prevent and treat HFpEF. Follistatin-like 1 (Fstl1), a divergent member of the follistatin family of extracellular glycoproteins, has previously been shown to be elevated in HF with reduced ejection fraction and associated with increased left ventricular mass. In this study, blood levels of Fstl1 were increased in humans with HFpEF. This increase was also evident in mice with hypertension-induced HFpEF and adult rat ventricular myocytes stimulated with aldosterone. Treatment with recombinant Fstl1 abrogated aldosterone-induced cardiac myocyte hypertrophy, suggesting a role for Fstl1 in the regulation of hypertrophy in HFpEF. There was also a reduction in the E/A ratio, a measure of diastolic dysfunction. Furthermore, HFpEF induced in a mouse model that specifically ablates Fstl1 in cardiac myocytes (cardiac myocyte-specific Fstl1 knockout [cFstl1-KO]) showed exacerbation of HFpEF with worsened diastolic dysfunction. In addition, cFstl1-KO-HFpEF mice demonstrated more marked cardiac myocyte hypertrophy with increased molecular markers of atrial natriuretic peptide and brain natriuretic peptide expression. These findings indicate that Fstl1 exerts therapeutic effects by modulating cardiac hypertrophy in HFpEF.

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Fstl1, also known as transforming growth factor-β–stimulated clone 36, is an extra-cellular glycoprotein implicated in the pathophysiology of cardiac disease.

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Fstl1 acts in a noncanonical manner relative to other follistatin family members, but its functions remain poorly understood.

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Circulating Flst1 levels are increased in humans with chronic stable HFpEF.

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Fstl1 treatment modulates cardiomyocyte hypertrophy in vitro and in vivo.

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Cardiac myocyte deletion of Fstl1 worsens the HFpEF phenotype in mice.

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These studies indicate that Fstl1 may be therapeutically effective in HFpEF by modulating cardiac hypertrophy and improving parameters of diastolic dysfunction.

Cardiosphere-derived cells reverse heart failure with preserved ejection fraction (HFpEF) in rats by decreasing fibrosis and inflammation

The pathogenesis of heart failure with a preserved ejection fraction (HFpEF) is unclear. Myocardial fibrosis, inflammation, and cardiac hypertrophy have been suggested to contribute to the pathogenesis of HFpEF. Cardiosphere-derived cells (CDCs) are heart-derived cell products with antifibrotic and anti-inflammatory properties. This study tested whether rat CDCs were sufficient to decrease manifestations of HFpEF in hypertensive rats. Starting at 7 weeks of age, Dahl salt-sensitive rats were fed a high-salt diet for 6 to 7 weeks and randomized to receive intracoronary CDCs or placebo. Dahl rats fed normal chow served as controls. High-salt rats developed hypertension, left ventricular (LV) hypertrophy, and diastolic dysfunction, without impairment of ejection fraction. Four weeks after treatment, diastolic dysfunction resolved in CDC-treated rats but not in placebo. The improved LV relaxation was associated with lower LV end-diastolic pressure, decreased lung congestion, and enhanced survival in CDC-treated rats. Histology and echocardiography revealed no decrease in cardiac hypertrophy after CDC treatment, consistent with the finding of sustained, equally-elevated blood pressure in CDC- and placebo-treated rats. Nevertheless, CDC treatment decreased LV fibrosis and inflammatory infiltrates. Serum inflammatory cytokines were likewise decreased after CDC treatment. Whole-transcriptome analysis revealed that CDCs reversed changes in numerous transcripts associated with HFpEF, including many involved in inflammation and/or fibrosis. These studies suggest that CDCs normalized LV relaxation and LV diastolic pressure while improving survival in a rat model of HFpEF. The benefits of CDCs occurred despite persistent hypertension and cardiac hypertrophy. By selectively reversing inflammation and fibrosis, CDCs may be beneficial in the treatment of HFpEF.

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The pathogenesis of heart failure with a preserved ejection fraction (HFpEF) is unclear.

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Cardiosphere-derived cells (CDCs) are heart-derived cell products with antifibrotic and anti-inflammatory properties, which have been implicated in HFpEF.

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Dahl salt-sensitive rats were fed a high-salt diet for 6 to7 weeks and randomized to receive intracoronary CDCs or placebo.

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Following CDC treatment, diastolic dysfunction resolved in treated rats but not in the placebo group. Treatment with CDCs also lower LV end-diastolic pressure, decrease lung congestion, and enhance survival.

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CDC treatment decreased LV fibrosis and inflammatory infiltrates, and reversed many of the transcriptomic changes associated with HFpEF, but had no effect on cardiac hypertrophy.

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By selectively reversing inflammation and fibrosis, CDCs may be beneficial in the treatment of HFpEF.

Management of heart failure with preserved ejection fraction: a review

PURPOSE

The purpose of this article was to review the clinical management of patients with heart failure with preserved ejection fraction (HFPEF).

METHODS

For this critical review, electronic databases (MEDLINE, EMBASE, PubMed) were searched for relevant basic research studies and randomized clinical trials recently published or presented at major meetings. Details of in-progress or planned studies were obtained from the ClinicalTrials.gov website. The range of publication dates was the year 2000 to 2015. Search terms included HFPEF, heart failure with preserved ejection fraction, HFPSF, heart failure with preserved systolic function, diastolic heart failure, diastolic dysfunction, HFNEF, heart failure with normal ejection fraction, treatment, management, therapy.

FINDINGS

Patients with HFPEF account for up to half of all patients with a clinical diagnosis of HF. Key contributing factors include hypertension, obesity, and atrial fibrillation, and other chronic diseases, including diabetes, chronic obstructive pulmonary disease, and anemia, frequently coexist. To date, large-scale clinical trials, particularly those focused on antagonism of the renin-angiotensin-aldosterone system, have provided limited evidence of clinical benefit.

IMPLICATIONS

The aggressive management of contributing factors, including hypertension, atrial fibrillation, and myocardial ischemia, is key in the management of HFPEF. New insights into the mechanisms and thus the identification of potential therapeutic strategies are urgently required.