Endotoxin and immune activation in chronic heart failure: a prospective cohort study

Circadian misalignment by environmental light/dark shifting causes circadian disruption in colon

BACKGROUND

Physiological circadian rhythms (CRs) are complex processes with 24-hour oscillations that regulate diverse biological functions. Chronic weekly light/dark (LD) shifting (CR disruption; CRD) in mice results in colonic hyperpermeability. However, the mechanisms behind this phenomenon are incompletely understood. One potential innovative in vitro method to study colonic CRs are colon organoids. The goals of this study were to utilize circadian clock gene Per2 luciferase reporter (Per2::Luc) mice to measure the effects of chronic LD shifting on colonic tissue circadian rhythmicity ex vivo and to determine if organoids made from shifted mice colons recapitulate the in vivo phenotype.

METHODS

Non-shifted (NS) and shifted (S) BL6 Per2::Luc mice were compared after a 22-week experiment. NS mice had a standard 12h light/12h dark LD cycle throughout. S mice alternated 12h LD patterns weekly, with light from 6am-6pm one week followed by shifting light to 6pm-6am the next week for 22 weeks. Mice were tested for intestinal permeability while colon tissue and organoids were examined for CRs of bioluminescence and proteins of barrier function and cell fate.

RESULTS

There was no absolute difference in NS vs. S 24h circadian period or phase. However, chronic LD shifting caused Per2::Luc S mice colon tissue to exhibit significantly greater variability in both the period and phase of Per2::Luc rhythms than NS mice colon tissue and organoids. Chronic LD shifting also resulted in increased colonic permeability of the Per2::Luc mice as well as decreased protein markers of intestinal permeability in colonic tissue and organoids from shifted Per2:Luc mice.

CONCLUSIONS

Our studies support a model in which chronic central circadian disruption by LD shifting alters the circadian phenotype of the colon tissue and results in colon leakiness and loss of colonic barrier function. These CRD-related changes are stably expressed in colon stem cell derived organoids from CRD mice.

The Neuroimmune Role of Intestinal Microbiota in the Pathogenesis of Cardiovascular Disease

Currently, a bidirectional relationship between the gut microbiota and the nervous system, which is considered as microbiota-gut-brain axis, is being actively studied. This axis is believed to be a key mechanism in the formation of somatovisceral functions in the human body. The gut microbiota determines the level of activation of the hypothalamic-pituitary system. In particular, the intestinal microbiota is an important source of neuroimmune mediators in the pathogenesis of cardiovascular disease. This review reflects the current state of publications in PubMed and Scopus databases until December 2020 on the mechanisms of formation and participation of neuroimmune mediators associated with gut microbiota in the development of cardiovascular disease.

The emerging role of gut microbiota in cardiovascular diseases

There is mounting evidence which suggests the involvement of gut microbiota dysbiosis in the pathogenesis of various cardiovascular diseases (CVD) and associated risk states such as hypertension, type 2 diabetes, obesity and dyslipidaemia, atherosclerosis, heart failure and atrial fibrillation. The current review comprehensively summarizes the various pathogenetic mechanisms of dysbiosis in these conditions and discusses the key therapeutic implications. Further deeper understanding of the pathogenetic links between CVD and gut microbiota dysbiosis can aid in the development of novel microbiota-based targets for the management of CVDs.

Two Gut Microbiota-Derived Toxins Are Closely Associated with Cardiovascular Diseases: A Review

Cardiovascular diseases (CVDs) have become a major health problem because of the associated high morbidity and mortality rates observed in affected patients. Gut microbiota has recently been implicated as a novel endocrine organ that plays critical roles in the regulation of cardiometabolic and renal functions of the host via the production of bioactive metabolites. This review investigated the evidence from several clinical and experimental studies that indicated an association between the gut microbiota-derived toxins and CVDs. We mainly focused on the pro-inflammatory gut microbiota-derived toxins, namely lipopolysaccharides, derived from Gram-negative bacteria, and trimethylamine N-oxide and described the present status of research in association with these toxins, including our previous research findings. Several clinical studies aimed at exploring the effectiveness of reducing the levels of these toxins to inhibit cardiovascular events are currently under investigation or in the planning stages. We believe that some of the methods discussed in this review to eliminate or reduce the levels of such toxins in the body could be clinically applied to prevent CVDs in the near future.

Association of Small Intestinal Bacterial Overgrowth With Heart Failure and Its Prediction for Short-Term Outcomes

Background Small intestinal bacterial overgrowth (SIBO) is a common pathological condition of intestinal microbiota. The prevalence of SIBO and its prognostic value in patients with heart failure (HF) are unknown. Methods and Results A total of 287 patients tested for SIBO using lactulose hydrogen-methane breath test were evaluated. At least 1 of the following criteria fulfilled was SIBO positive: patients with fasting hydrogen level ≥20 parts per million (ppm) or a ≥20 ppm rise in hydrogen by 90 minutes were diagnosed with SIBO (H₂) positive; and patients with methane levels ≥10 ppm at any test point were diagnosed with SIBO (CH₄) positive. The association between SIBO and the composite of cardiovascular death and HF rehospitalization was investigated. In 287 consecutive patients with HF, 128 (45%) were positive for SIBO. Our result showed SIBO increased the risk of HF rehospitalization in patients with HF with reduced ejection fraction (P<0.001), and the risk of cardiovascular death in patients with HF with preserved EF (P=0.011). SIBO was an independent risk factor of primary end point in patients with HF (hazard ratio [HR], 2.13; 95% CI; 1.26-3.58; P=0.005). In addition, SIBO (CH₄) showed a prognostic value on adverse outcomes (HR, 2.35; 95% CI, 1.38-4.02; P<0.001), whereas the association between SIBO (H₂) and outcomes was not statistically significant. Conclusions There was high prevalence of SIBO in patients with HF, and SIBO was independently associated with poor outcomes. Proactive treatment for SIBO may provide extra benefit for patients with HF.

Re-appraisal of the obesity paradox in heart failure: a meta-analysis of individual data

Background

Higher body mass index (BMI) is associated with better outcome compared with normal weight in patients with HF and other chronic diseases. It remains uncertain whether the apparent protective role of obesity relates to the absence of comorbidities. Therefore, we investigated the effect of BMI on outcome in younger patients without co-morbidities as compared to older patients with co-morbidities in a large heart failure (HF) population.

Methods

In an individual patient data analysis from pooled cohorts, 5,819 patients with chronic HF and data available on BMI, co-morbidities and outcome were analysed. Patients were divided into four groups based on BMI (i.e. ≤ 18.5 kg/m², 18.5–25.0 kg/m²; 25.0–30.0 kg/m²; 30.0 kg/m²). Primary endpoints included all-cause mortality and HF hospitalization-free survival.

Results

Mean age was 65 ± 12 years, with a majority of males (78%), ischaemic HF and HF with reduced ejection fraction. Frequency of all-cause mortality or HF hospitalization was significantly worse in the lowest two BMI groups as compared to the other two groups; however, this effect was only seen in patients older than 75 years or having at least one relevant co-morbidity, and not in younger patients with HF only. After including medications and N-terminal pro-B-type natriuretic peptide and high-sensitivity cardiac troponin concentrations into the model, the prognostic impact of BMI was largely absent even in the elderly group with co-morbidity.

Conclusions

The present study suggests that obesity is a marker of less advanced disease, but does not have an independent protective effect in patients with chronic HF.

Graphic abstract

Categories of BMI are only predictive of poor outcome in patients aged > 75 years or with at least one co-morbidity (bottom), but not in those aged < 75 years without co-morbidities (top). The prognostic effect largely disappears in multivariable analyses even for the former group. These findings question the protective effect of obesity in chronic heart failure (HF).

Supplementary Information

The online version contains supplementary material available at 10.1007/s00392-021-01822-1.

Persistent congestion, renal dysfunction and inflammatory cytokines in acute heart failure: a prognosis study

AIMS

Chronic kidney dysfunction (CKD) and persistent congestion influence heart failure prognosis, but little is known about the role of inflammation in this association. We assessed the relationship between inflammatory biomarkers, persistent congestion and CKD and their prognostic implications in patients with acute heart failure.

METHODS

We enrolled 97 hospitalised patients (mean age: 66 ± 12 years, ejection fraction: 30 ± 8%) with acute heart failure. Before discharge, congestion was assessed using a heart failure scoring system on the basis of Framingham criteria. Circulating levels of high-sensitivity C-reactive protein, TGF-β-1, IL-1, IL-6, IL-10, TNF-α, soluble tumour necrosis factor receptor type 1 and 2 were measured. Patients were divided into four groups according to the presence of CKD (estimated glomerular filtration rate <60 ml/min/1.73 m) and congestion (Framingham heart failure score ≥2). The primary end point was the combination of death and rehospitalisation for acute heart failure.

RESULTS

During a median follow-up of 32 months, 37 patients died and 14 were rehospitalised for acute heart failure. Patients with CKD and congestion had significantly higher TNF-α (P = 0.037), soluble tumour necrosis factor receptor type 1 (P = 0.0042) and soluble tumour necrosis factor receptor type 2 (P = 0.001), lower TGF-β-1 (P = 0.02) levels, and the worst outcome (P < 0.0001). Congestion (P = 0.01) and CKD (P = 0.02) were independent predictors of the end-point together with N-terminal prohormone of brain natriuretic peptide (P = 0.002) and TNF-α (P = 0.004). TNF-α attenuated the direct relation between CKD, congestion and outcome, explaining 40% of the difference in the outcome.

CONCLUSION

In patients hospitalised with acute heart failure, the prognostic impact of persistent congestion and CKD is associated with increased cytokine levels, which may also interfere with the outcome.

Association between Daily Urinary Sodium Excretion, Ratio of Extracellular Water-to-Total Body Water Ratio, and Kidney Outcome in Patients with Chronic Kidney Disease

Whether dietary salt intake affects chronic kidney disease (CKD) progression remains unclear. We conducted a retrospective cohort study to analyze the effects of both daily salt intake (DSI) and volume status on renal outcomes in 197 CKD patients. DSI was estimated by 24-h urinary sodium excretion and volume status was assessed by the ratio of extracellular water (ECW) to total body water (TBW) measured by bioelectrical impedance analysis (BIA). We divided patients into two groups according to DSI (6 g/day) or median ECW/TBW (0.475) and compared renal outcomes of each group. Furthermore, we classified and analyzed four groups according to both DSI and ECW/TBW. The higher DSI group showed a 1.69-fold (95% confidence interval (CI) 1.12–2.57, p = 0.01) excess risk of outcome occurrence compared to the lower group. Among the four groups, compared with Group 1 (low DSI and low ECW/TBW), Group 3 (high DSI and low ECW/TBW) showed a 1.84-fold (95% CI 1.03–3.30, p = 0.04) excess risk of outcome occurrence; however, Group 2 (low DSI and high ECW/TBW) showed no significant difference. High salt intake appears to be associated with poor renal outcome independent of blood pressure (BP), proteinuria, and volume status.

Exploring the Potential Role of the Gut Microbiome in Chemotherapy-Induced Neurocognitive Disorders and Cardiovascular Toxicity

Chemotherapy, targeting not only malignant but also healthy cells, causes many undesirable side effects in cancer patients. Due to this fact, long-term cancer survivors often suffer from late effects, including cognitive impairment and cardiovascular toxicity. Chemotherapy damages the intestinal mucosa and heavily disrupts the gut ecosystem, leading to gastrointestinal toxicity. Animal models and clinical studies have revealed the associations between intestinal dysbiosis and depression, anxiety, pain, impaired cognitive functions, and cardiovascular diseases. Recently, a possible link between chemotherapy-induced gut microbiota disruption and late effects in cancer survivors has been proposed. In this review, we summarize the current understanding of preclinical and clinical findings regarding the emerging role of the microbiome and the microbiota-gut-brain axis in chemotherapy-related late effects affecting the central nervous system (CNS) and heart functions. Importantly, we provide an overview of clinical trials evaluating the relationship between the gut microbiome and cancer survivorship. Moreover, the beneficial effects of probiotics in experimental models and non-cancer patients with neurocognitive disorders and cardiovascular diseases as well as several studies on microbiota modulations via probiotics or fecal microbiota transplantation in cancer patients are discussed.

Association of Gut Hormones and Microbiota with Vascular Dysfunction in Obesity

In the past few decades, obesity has reached pandemic proportions. Obesity is among the main risk factors for cardiovascular diseases, since chronic fat accumulation leads to dysfunction in vascular endothelium and to a precocious arterial stiffness. So far, not all the mechanisms linking adipose tissue and vascular reactivity have been explained. Recently, novel findings reported interesting pathological link between endothelial dysfunction with gut hormones and gut microbiota and energy homeostasis. These findings suggest an active role of gut secretome in regulating the mediators of vascular function, such as nitric oxide (NO) and endothelin-1 (ET-1) that need to be further investigated. Moreover, a central role of brain has been suggested as a main player in the regulation of the different factors and hormones beyond these complex mechanisms. The aim of the present review is to discuss the state of the art in this field, by focusing on the processes leading to endothelial dysfunction mediated by obesity and metabolic diseases, such as insulin resistance. The role of perivascular adipose tissue (PVAT), gut hormones, gut microbiota dysbiosis, and the CNS function in controlling satiety have been considered. Further understanding the crosstalk between these complex mechanisms will allow us to better design novel strategies for the prevention of obesity and its complications.

Rigorous Plasma Microbiome Analysis Method Enables Disease Association Discovery in Clinic

Blood microbiome is important to investigate microbial-host interactions and the effects on systemic immune perturbations. However, this effort has met with major challenges due to low microbial biomass and background artifacts. In the current study, microbial 16S DNA sequencing was applied to analyze plasma microbiome. We have developed a quality-filtering strategy to evaluate and exclude low levels of microbial sequences, potential contaminations, and artifacts from plasma microbial 16S DNA sequencing analyses. Furthermore, we have applied our technique in three cohorts, including tobacco-smokers, HIV-infected individuals, and individuals with systemic lupus erythematosus (SLE), as well as corresponding controls. More than 97% of total sequence data was removed using stringent quality-filtering strategy analyses; those removed amplicon sequence variants (ASVs) were low levels of microbial sequences, contaminations, and artifacts. The specifically enriched pathobiont bacterial ASVs have been identified in plasmas from tobacco-smokers, HIV-infected individuals, and individuals with SLE but not from control subjects. The associations between these ASVs and disease pathogenesis were demonstrated. The pathologic activities of some identified bacteria were further verified in vitro. We present a quality-filtering strategy to identify pathogenesis-associated plasma microbiome. Our approach provides a method for studying the diagnosis of subclinical microbial infection as well as for understanding the roles of microbiome-host interaction in disease pathogenesis.

Gut microbiome - A potential mediator of pathogenesis in heart failure and its comorbidities: State-of-the-art review

Gut microbiome (GMB) has been increasingly recognized as a contributor to development and progression of heart failure (HF), immune-mediated subtypes of cardiomyopathy (myocarditis and anthracycline-induced cardiotoxicity), response to certain cardiovascular drugs, and HF-related comorbidities, such as chronic kidney disease, cardiorenal syndrome, insulin resistance, malnutrition, and cardiac cachexia. Gut microbiome is also responsible for the "gut hypothesis" of HF, which explains the adverse effects of gut barrier dysfunction and translocation of GMB on the progression of HF. Furthermore, accumulating evidence has suggested that gut microbial metabolites, including short chain fatty acids, trimethylamine N-oxide (TMAO), amino acid metabolites, and bile acids, are mechanistically linked to pathogenesis of HF, and could, therefore, serve as potential therapeutic targets for HF. Even though there are a variety of proposed therapeutic approaches, such as dietary modifications, prebiotics, probiotics, TMAO synthesis inhibitors, and fecal microbial transplant, targeting GMB in HF is still in its infancy and, indeed, requires further preclinical and clinical evidence. In this review, we aim to highlight the role gut microbiome plays in HF pathophysiology and its potential as a novel therapeutic target in HF.

Gut dysbiosis induced by cardiac pressure overload enhances adverse cardiac remodeling in a T cell-dependent manner

Despite the existing association of gut dysbiosis and T cell inflammation in heart failure (HF), whether and how gut microbes contribute to T cell immune responses, cardiac fibrosis and dysfunction in HF remains largely unexplored. Our objective was to investigate whether gut dysbiosis is induced by cardiac pressure overload, and its effect in T cell activation, adverse cardiac remodeling, and cardiac dysfunction. We used 16S rRNA sequencing of fecal samples and discovered that cardiac pressure overload-induced by transverse aortic constriction (TAC) results in gut dysbiosis, characterized by a reduction of tryptophan and short-chain fatty acids producing bacteria in WT mice, but not in T cell-deficient mice (Tcra-/- ) mice. These changes did not result in T cell activation in the gut or gut barrier disruption. Strikingly, microbiota depletion in WT mice resulted in decreased heart T cell infiltration, decreased cardiac fibrosis, and protection from systolic dysfunction in response to TAC. Spontaneous reconstitution of the microbiota partially reversed these effects. We observed decreased cardiac expression of the Aryl hydrocarbon receptor (AhR) and enzymes associated with tryptophan metabolism in WT mice, but not in Tcra-/- mice, or in mice depleted of the microbiota. These findings demonstrate that cardiac pressure overload induced gut dysbiosis and T cell immune responses contribute to adverse cardiac remodeling, and identify the potential contribution of tryptophan metabolites and the AhR to protection from adverse cardiac remodeling and systolic dysfunction in HF.

Targeting gut barrier dysfunction with phytotherapies: Effective strategy against chronic diseases

The intestinal epithelial layer serves as a physical and functional barrier between the microbe-rich lumen and immunologically active submucosa; it prevents systemic translocation of microbial pyrogenic products (e.g. endotoxin) that elicits immune activation upon translocation to the systemic circulation. Loss of barrier function has been associated with chronic 'low-grade' systemic inflammation which underlies pathogenesis of numerous no-communicable chronic inflammatory disease. Thus, targeting gut barrier dysfunction is an effective strategy for the prevention and/or treatment of chronic disease. This review intends to emphasize on the beneficial effects of herbal formulations, phytochemicals and traditional phytomedicines in attenuating intestinal barrier dysfunction. It also aims to provide a comprehensive understanding of intestinal-level events leading to a 'leaky-gut' and systemic complications mediated by endotoxemia. Additionally, a variety of detectable markers and diagnostic criteria utilized to evaluate barrier improving capacities of experimental therapeutics has been discussed. Collectively, this review provides rationale for targeting gut barrier dysfunction by phytotherapies for treating chronic diseases that are associated with endotoxemia-induced systemic inflammation.

Characteris Tics and Causes of Immune Dysfunction Related to Uremia and Dialysis

From the immunologic viewpoint, chronic kidney disease (CKD) is characterized by disorders of both the innate and adaptive systems, generating a complex and still not fully understood immune dysfunction. Markers of a chronically activated immune system are closely linked to several complications of CKD and represent powerful predictors for mortality in the CKD population. On the other hand, CKD patients respond poorly to vaccination and to challenges such as bacterial infection. Interestingly, the main causes of death in patients with CKD are cardiovascular and infectious diseases, both being pathologic processes closely linked to immune function. Therefore, accelerated tissue degeneration (as a consequence of chronic inflammation) and increased rate of sepsis (because of a poorly orchestrated immune response) represent the most important targets for interventions aiming to reduce mortality in CKD patients. Understanding the mechanisms behind the immune dysfunction that is peculiar to CKD generates a perspective to improve outcomes in this group of patients.

Risk Factors for Cardiovascular Disease in Patients Undergoing Peritoneal Dialysis

Patients on peritoneal dialysis (PD) are at high cardiovascular risk. Although some risk factors are unmodifiable (for example, age, sex, genetics), others are exacerbated in the unfriendly uremic milieu (inflammation, oxidative stress, mineral disturbances) or contribute per se to kidney disease and cardiovascular progression (diabetes mellitus, hypertension). Moreover, several factors associated with PD therapy may both increase (by altered lipid profile, hyperinsulinemia, and formation of advanced glycation end-products) and decrease (by better blood pressure control and anemia management) cardiovascular risk. The present review discusses recent findings and therapy trends in cardiovascular research on the PD population, with emphasis on the roles of inflammation, insulin resistance, homocysteinemia, dyslipidemia, vascular calcification, and genetics/epigenetics.

Prognostic value of DCTA scoring system in heart failure

OBJECTIVE

The aim of this study was to evaluate the prognostic value of a novel scoring system, based on D‑dimer, total cholesterol, high-sensitivity cardiac troponin T (hs-cTnT), and serum albumin levels, in patients with heart failure.

METHODS

A total of 221 patients diagnosed with heart failure between May 2016 to January 2020 were enrolled in this retrospective study. The prognostic significance of the biomarkers D‑dimer, total cholesterol, hs-cTnT, and serum albumin was determined with univariate and multivariate Cox proportional hazard models. A novel prognostic score based on these predictors was established. The Kaplan-Meier method and log-rank test were used to compare the adverse outcomes of patients in different risk groups.

RESULT

Results from univariate and multivariate analyses showed that high D‑dimer, low serum albumin, high hs-cTnT, and low total cholesterol levels were independent prognostic factors for adverse outcomes (D-dimer >0.63 mg/l, HR = 1.84, 95% CI = 1.16-2.94, p = 0.010; serum albumin >34 g/l, HR = 0.67, 95% CI = 0.45-0.99, p = 0.046; hs-cTnT >24.06 pg/ml, HR = 1.65, 95% CI = 1.08-2.53, p = 0.020; total cholesterol >3.68 mmol/l, HR = 0.63, 95% CI = 0.43-0.92, p = 0.017). Moreover, all the patients were stratified into low-risk or high-risk group according to a scoring system based on these four markers. Kaplan-Meier analyses demonstrated that patients in the high-risk group were more prone to having adverse outcomes compared with patients in the low-risk group.

CONCLUSION

D‑dimer, total cholesterol, hs-cTnT, and serum albumin levels were independent prognostic factors in the setting of heart failure. A novel and comprehensive scoring system based on these biomarkers is an easily available and effective tool for predicting the adverse outcomes of patients with heart failure.

Treatment of right ventricular dysfunction and heart failure in pulmonary arterial hypertension

Right heart dysfunction and failure is the principal determinant of adverse outcomes in patients with pulmonary arterial hypertension (PAH). In addition to right ventricular (RV) dysfunction, systemic congestion, increased afterload and impaired myocardial contractility play an important role in the pathophysiology of RV failure. The behavior of the RV in response to the hemodynamic overload is primarily modulated by the ventricular interaction and its coupling to the pulmonary circulation. The presentation can be acute with hemodynamic instability and shock or chronic producing symptoms of systemic venous congestion and low cardiac output. The prognostic factors associated with poor outcomes in hospitalized patients include systemic hypotension, hyponatremia, severe tricuspid insufficiency, inotropic support use and the presence of pericardial effusion. Effective therapeutic management strategies involve identification and effective treatment of the triggering factors, improving cardiopulmonary hemodynamics by optimization of volume to improve diastolic ventricular interactions, improving contractility by use of inotropes, and reducing afterload by use of drugs targeting pulmonary circulation. The medical therapies approved for PAH act primarily on the pulmonary vasculature with secondary effects on the right ventricle. Mechanical circulatory support as a bridge to transplantation has also gained traction in medically refractory cases. The current review was undertaken to summarize recent insights into the evaluation and treatment of RV dysfunction and failure attributable to PAH.

Serum concentrations of free fatty acids are associated with 3-month mortality in acute heart failure patients

Background

Plasma free fatty acids (FFA) are higher in heart failure (HF) patients compared to healthy controls. Considering that the extent of FFA elevation in HF might mirror the severity of HF, we hypothesized that the serum levels of FFA may be a useful prognostic indicator for 3-month mortality in acute heart failure (AHF).

Methods

We analyzed the serum samples of AHF patients obtained at admission to the emergency department. Serum levels of FFA were analyzed using an enzymatic reagent on an automatic analyzer.

Results

Out of 152 included AHF patients that were originally included, serum samples of 132 patients were available for the quantification of FFA. Of these, 35 (26.5%) died within 3 months of onset of AHF. These patients had significantly higher serum levels of FFA compared to AHF patients who were alive 3 months after onset of AHF. Univariable logistic regression analyses showed a significant positive association of FFA levels with 3-month mortality (odds ratio [OR] 2.76 [95% confidence interval 1.32–6.27], p = 0.010). Importantly, this association remained significant after adjusting for age and sex, as well as for further clinical and laboratory parameters that showed a significant association with 3-month mortality in the univariate analyses.

Conclusions

We conclude that the admission serum levels of FFA are associated with 3-month mortality in AHF patients. Therefore, measurements of circulating FFA levels may help identifying high-risk AHF patients.

Gut Microbiota and Cardiovascular Disease

Fecal microbial community changes are associated with numerous disease states, including cardiovascular disease (CVD). However, such data are merely associative. A causal contribution for gut microbiota in CVD has been further supported by a multitude of more direct experimental evidence. Indeed, gut microbiota transplantation studies, specific gut microbiota-dependent pathways, and downstream metabolites have all been shown to influence host metabolism and CVD, sometimes through specific identified host receptors. Multiple metaorganismal pathways (involving both microbe and host) both impact CVD in animal models and show striking clinical associations in human studies. For example, trimethylamine N-oxide and, more recently, phenylacetylglutamine are gut microbiota-dependent metabolites whose blood levels are associated with incident CVD risks in large-scale clinical studies. Importantly, a causal link to CVD for these and other specific gut microbial metabolites/pathways has been shown through numerous mechanistic animal model studies. Phenylacetylglutamine, for example, was recently shown to promote adverse cardiovascular phenotypes in the host via interaction with multiple ARs (adrenergic receptors)-a class of key receptors that regulate cardiovascular homeostasis. In this review, we summarize recent advances of microbiome research in CVD and related cardiometabolic phenotypes that have helped to move the field forward from associative to causative results. We focus on microbiota and metaorganismal compounds/pathways, with specific attention paid to short-chain fatty acids, secondary bile acids, trimethylamine N-oxide, and phenylacetylglutamine. We also discuss novel therapeutic strategies for directly targeting the gut microbiome to improve cardiovascular outcomes.

Lymphocytopenia During Hospitalization for Acute Heart Failure and Its Relationship With Portal Congestion and Right Ventricular Function

BACKGROUND

Lymphocytopenia is associated with mortality in acute heart failure (AHF), and portal congestion has been suggested to play a role in leukocyte distribution. The associations between lymphocytopenia and ultrasound surrogates for portal congestion have never been studied. We aimed to characterize the determinants of lymphocytopenia, explore the associations between lymphocytopenia and portal congestion, and explore the relationships between lymphocytopenia and outcomes in AHF.

METHODS AND RESULTS

Patients were compared according to tertiles of lymphocyte count (very low, <0.87 × 10⁹/L; low, 0.87-1.2 × 10⁹/L; or normal, >1.2 × 10⁹/L). One hundred three patients with AHF were prospectively assessed at baseline and discharge. At baseline, 69% of patients had a lymphocyte count below the normal range. Patients with baseline very low lymphocyte count were older, had more advanced disease and higher portal vein pulsatility index when compared with those in the higher tertiles. Very low lymphocyte count at baseline was associated with age (odds ratio (OR) 1.098), portal vein pulsatility index (OR, 1.026), and tricuspid annular plane systolic excursion (OR, 0.865, all P < .05). The portal vein pulsatility index was the most powerful determinant of lymphocytopenia at discharge (OR 1.033, P < .05). In a Cox model, lymphocytopenia at discharge was associated with mortality (hazard ratio 4.796, P < .05).

CONCLUSIONS

In AHF, lymphocytopenia is associated with ultrasound surrogates for portal congestion and right ventricular dysfunction. Whether these associations depict a potent pathophysiologic pathway or whether they only reflect a more advanced disease remains uncertain.

Contentious role of 'Good Adiponectin' in pulmonary and cardiovascular diseases: Is adiponectin directed therapy a boon or a bane?

After two decades of its discovery, numerous facts of adiponectin (APN) biology has been uncovered, yet, APN remains an elusive adipokine. Findings from clinical studies and animal models established APN's ameliorative role in cardiovascular disease (CVD) and pulmonary disease (PD) but the same condition is prognostic for mortality in the same set of patients which cornered APN towards a dubious state. A repertoire of mechanisms associated with the positive association of APN in both lean/cachectic or obese CVD and PD patients from past publications are evaluated. Newer pharmacological agent may be explored to regulate elevated blood APN concentration in COPD or CHF patients whereas administration of recombinant APN as well as growth hormone may augment blood APN concentration in obese subjects associated with low blood and intracellular APN concentration. However, some APN directed therapy in clinical as well as in pre-clinical setup has pronounced some contentious effects. After reviewing the mechanisms of the contentious role of APN functioning in pathologic conditions of CVD and PD in both lean and obese conditions, the authors came to conclusion that APN directed therapy may be utilized with caution keeping in mind the different age group, sex and the different CVD as well as pulmonary diseases they are suffering from.

Higher fatty liver index is associated with increased risk of new onset heart failure in healthy adults: a nationwide population-based study in Korea

Background

Heart failure (HF) is relatively common cardiovascular disease with high mortality and morbidity. Although it is associated with many cardiovascular risk factors, the association between nonalcoholic fatty liver disease (NAFLD), the most common chronic liver disease, and HF has not been evaluated in a large-scale cohort study. Thus, we evaluated the ability of the fatty liver Index (FLI), a surrogate marker of NAFLD, to predict the development of HF in healthy individuals.

Methods

We analyzed the association between the FLI and new-onset HF with multivariate Cox proportional-hazards models in 308,578 healthy persons without comorbidities who underwent the National Health check-ups in the republic of Korea from 2009 to 2014.

Results

A total of 2532 subjects (0.8%) were newly diagnosed with HF during the study period (a median of 5.4 years). We categorized our subjects into quartile groups according to FLI (Q1, 0–4.9; Q2, 5.0–12.5; Q3, 12.6–31.0; and Q4, > 31.0). The cumulative incidence of HF was significantly higher in the highest FLI group than in the lowest FLI group (Q1, 307 [0.4%] and Q4, 890 [1.2%]; P < 0.001). Adjusted hazard ratio (HRs) indicated that the highest FLI group was independently associated with an increased risk for HF (HR between Q4 and Q1, 2.709; 95% confidence interval = 2.380–3.085; P < 0.001). FLI was significantly associated with an increased risk of new-onset HF regardless of their baseline characteristics.

Conclusions

Higher FLI was independently associated with increased risk of HF in a healthy Korean population.

Soluble CD14 and Risk of Heart Failure and Its Subtypes in Older Adults

BACKGROUND

CD14 is a membrane glycoprotein primarily expressed by myeloid cells that plays a key role in inflammation. Soluble CD14 (sCD14) levels carry a poor prognosis in chronic heart failure (HF), but whether elevations in sCD14 precede HF is unknown. We tested the hypothesis that sCD14 is associated with HF incidence and its subtypes independent of major inflammatory biomarkers among older adults.

METHODS AND RESULTS

We included participants in the Cardiovascular Health Study without preexisting HF and available baseline sCD14. We evaluated the associations of sCD14, high-sensitivity C-reactive protein (hsCRP), interleukin (IL)-6, and white blood cell count (WBC) with incident HF and subtypes using Cox regression. Among 5217 participants, 1878 had incident HF over 13.6 years (609 classifiable as HF with preserved ejection fraction [HFpEF] and 419 as HF with reduced ejection fraction [HFrEF]). After adjusting for clinical and laboratory covariates, sCD14 was significantly associated with incident HF (hazard ratio [HR]: 1.56 per doubling, 95% confidence interval [CI]: 1.29-1.89), an association that was numerically stronger than for hsCRP (HR per doubling: 1.10, 95% CI: 1.06-1.15), IL-6 (HR: 1.18, 95% CI: 1.10-1.25), and WBC (HR: 1.24, 95% CI: 1.09-1.42), and that remained significant after adjustment for the other markers of inflammation. This association for sCD14 was observed with HFpEF (HR: 1.50, 95% CI: 1.07-2.10) but not HFrEF (HR: 0.99, 95% CI: 0.67-1.49).

CONCLUSIONS

Plasma sCD14 was associated with incident HF independently and numerically more strongly than other major inflammatory markers. This association was only observed with HFpEF in the subset with classifiable HF subtypes. Pending replication, these findings have potentially important therapeutic implications.

Right Heart Failure and Cardiorenal Syndrome

Cardiorenal syndrome is a complex interplay of dysregulated heart and kidney interaction that leads to multiorgan system dysfunction, which is not an uncommon occurrence in the setting of right heart failure. The traditional concept of impaired perfusion and forward flow recently has been modified to include the recognition of systemic venous congestion as a contributor, with direct and indirect mechanisms, including elevated renal venous pressure, reduced renal perfusion pressure, increased renal interstitial pressure, tubular dysfunction, splanchnic congestion, and neurohormonal and inflammatory activation. Treatment options beyond diuretics and vasoactive drugs remain limited and lack supportive evidence.

The Gut Microbiota and Its Implication in the Development of Atherosclerosis and Related Cardiovascular Diseases

The importance of gut microbiota in health and disease is being highlighted by numerous research groups worldwide. Atherosclerosis, the leading cause of heart disease and stroke, is responsible for about 50% of all cardiovascular deaths. Recently, gut dysbiosis has been identified as a remarkable factor to be considered in the pathogenesis of cardiovascular diseases (CVDs). In this review, we briefly discuss how external factors such as dietary and physical activity habits influence host-microbiota and atherogenesis, the potential mechanisms of the influence of gut microbiota in host blood pressure and the alterations in the prevalence of those bacterial genera affecting vascular tone and the development of hypertension. We will also be examining the microbiota as a therapeutic target in the prevention of CVDs and the beneficial mechanisms of probiotic administration related to cardiovascular risks. All these new insights might lead to novel analysis and CVD therapeutics based on the microbiota.

Biocompatibility of New Peritoneal Dialysis Solutions: What Can We Hope to Achieve?

Despite the bioincompatibility of the “old”, standard, high glucose, lactate-buffered peritoneal dialysis (PD) solutions, PD is itself a highly successful dialysis modality with patient survival equivalent to that of hemodialysis (HD) during the initial 3 – 5 years of dialysis therapy. Nevertheless, PD technique survival is often limited by infectious complications and alterations in the structure and function of the peritoneal membrane. These local changes also have a negative impact on patient survival owing to systemic effects such as those often seen in patients with high peritoneal transport rate and loss of ultrafiltration (UF) capacity.

Patient mortality remains unacceptably high in both HD and PD patients, with most premature deaths being associated with signs of malnutrition, inflammation, and atherosclerotic cardiovascular disease (MIA syndrome). These systemic signs are likely to be influenced by PD solutions both directly and indirectly (via changes in the peritoneal membrane). New, biocompatible PD solutions may have favorable local effects (viability and function of the peritoneal membrane) and systemic effects (for example, on MIA syndrome). Amino acid–based solution [Nutrineal (N): Baxter Healthcare Corporation, Deerfield, IL, U.S.A.] may improve nutritional status as well as peritoneal membrane viability. Bicarbonate/lactate–buffered solution [Physioneal (P): Baxter Healthcare Corporation] may ameliorate local and systemic effects of low pH, high lactate, and high glucose degradation products. Icodextrin-based solution [Extraneal (E): Baxter Healthcare SA, Castlebar, Ireland] may improve hypertension and cardiovascular problems associated with fluid overload and may extend time on therapy in patients with loss of UF capacity.

The positive effects of each of these new, biocompatible solutions have been demonstrated in several studies. It is likely that the combined use of N, P, and E solutions will produce favorable synergies in regard to both local effects (peritoneal viability) and systemic effects (less malnutrition, inflammation, and fluid overload). Solution combination is an exciting area for clinical study in the coming years. Furthermore, dialysis fluid additives such as hyaluronan, which protects and improves the function of the peritoneal membrane, may further improve PD solutions. The new, biocompatible PD solutions represent an entirely new era in the evolution of the PD therapy; they are likely to have markedly positive effects on both PD technique and PD patient survival in coming years.

Systemic Consequences of Pulmonary Hypertension and Right-Sided Heart Failure

Pulmonary hypertension (PH) is a feature of a variety of diseases and continues to harbor high morbidity and mortality. The main consequence of PH is right-sided heart failure which causes a complex clinical syndrome affecting multiple organ systems including left heart, brain, kidneys, liver, gastrointestinal tract, skeletal muscle, as well as the endocrine, immune, and autonomic systems. Interorgan crosstalk and interdependent mechanisms include hemodynamic consequences such as reduced organ perfusion and congestion as well as maladaptive neurohormonal activation, oxidative stress, hormonal imbalance, and abnormal immune cell signaling. These mechanisms, which may occur in acute, chronic, or acute-on-chronic settings, are common and precipitate adverse functional and structural changes in multiple organs which contribute to increased morbidity and mortality. While the systemic character of PH and right-sided heart failure is often neglected or underestimated, such consequences place additional burden on patients and may represent treatable traits in addition to targeted therapy of PH and underlying causes. Here, we highlight the current state-of-the-art understanding of the systemic consequences of PH and right-sided heart failure on multiple organ systems, focusing on self-perpetuating pathophysiological mechanisms, aspects of increased susceptibility of organ damage, and their reciprocal impact on the course of the disease.

Influence of Peritoneal Transport Rate, Inflammation, and Fluid Removal on Nutritional Status and Clinical Outcome in Prevalent Peritoneal Dialysis Patients

Objective

To evaluate the possible associations between peritoneal transport rate (PTR), fluid removal, inflammation, and nutritional status in patients treated with peritoneal dialysis (PD) for more than 6 months, and the impact of these factors on subsequent patient survival.

Design and Patients

A prospective study of 82 PD patients (48 males) that had been treated with PD more than 6 months. Based on the dialysate-to-plasma creatinine ratio at 4 hours of dwell (D/PCr; mean ± 1 SD), the patients were classified as having a high (H), high-average (HA), low-average (LA), or low (L) PTR.

Setting

Single PD unit in a university hospital.

Main Outcome Measures

The PTR, evaluation of adequacy of dialysis and nutritional status, and biochemical analyses were assessed at 10.8 ± 2.8 months after the start of PD.

Results

Compared to L and LA (L/LA) transporters, H and HA (H/HA) transporters had increased dialysate protein loss, glucose absorption from dialysate, and peritoneal creatinine clearance (CCr), and decreased night ultrafiltration volume and total Kt/V urea. However, nutritional variables, 24-hour total fluid removal (TFR), total CCr, and residual renal function were not significantly different between the two groups. The 24-hour TFR correlated significantly with D/PCr (rho = –0.25), mean arterial pressure (rho = –0.23), serum albumin (rho = 0.25), normalized protein equivalent of total nitrogen appearance (rho = 0.34), lean body mass (LBM) calculated from creatinine kinetics (rho = 0.41), total Kt/V urea (rho = 0.42), and total CCr (rho = 0.30). The group with serum C-reactive protein (sCRP) ⊕ 10 mg/L had a higher proportion of patients with reduced (< 1000 mL) TFR compared to the group with sCRP < 10 mg/(38% vs 16%, p = 0.04). Two-year patient survival rates from the time of the assessment were not different between the different transport groups (78% vs 73% for H/HA and L/LA, p = 0.99). Upon Cox proportional hazards multivariate analysis, age and high sCRP were independent predictors of mortality.

Conclusions

This study shows that, in a selected group of prevalent PD patients assessed after more than 6 months of PD therapy, ( 1 ) inflammation was an independent predictor for mortality; ( 2 ) reduced TFR was associated with impaired nutritional status, decreased small solute clearance, and inflammation; and ( 3 ) peritoneal transport status was not significantly associated with nutritional status and was not associated with subsequent patient survival. These results indicate that a high peritoneal solute transport rate, as such, should not be regarded as a relative contraindication for PD. Instead, the results suggest that more attention should be given to inflammation and inadequate fluid removal as predictors of mortality in PD patients.

Chronic Inflammation in Peritoneal Dialysis: The Search for the Holy Grail?

Mortality and morbidity in chronic kidney disease (CKD) patients are unacceptably high. The annual mortality rate due to cardiovascular disease (CVD) is approximately 9%, which, for the middle-aged person, is at least 10- to 20-fold higher than for the general population. Classic risk factors for CVD are highly prevalent in CKD patients, but they cannot fully account for the excessive rate of CVD in this population. Instead, it has become increasingly clear that nontraditional risk factors, such as systemic inflammation, may play a key role in the development of atherosclerosis. It is well established that inflammatory markers are very powerful predictors of high CVD morbidity and mortality not only in the general population, but particularly in CKD patients. Signs of a sustained low-grade inflammation, such as increased levels of C-reactive protein (CRP), are present in the majority of stage 5 CKD patients, even in patients in clinically stable condition, and they are also commonly observed after the initiation of dialysis therapy. Dialysis therapy — hemodialysis as well as peritoneal dialysis (PD) — may itself contribute to systemic inflammation. Local intraperitoneal inflammation can also occur in patients treated with PD. These local effects may result in a low-grade inflammation, caused by the bioincompatibility of conventional glucose-based dialysis fluids, to intense inflammation associated with peritonitis. Given these circumstances, it is reasonable to hypothesize that strategies aiming to reduce inflammation are potentially important and novel, and could serve to reduce CVD, thereby lowering morbidity and mortality in patients with CKD. In this review we provide information supporting the hypothesis that systemic inflammation is tightly linked to the most common complications of CKD patients, in particular those on PD, and that local inflammation in PD may contribute to various related complications. The aims of this review are to discuss the reasons that make inflammation an attractive target for intervention in CKD, the particular aspects of the inflammation–CVD axis during PD treatment that are likely involved, and possible means for the detection and management of chronic inflammation in PD patients.

Gut microbiota, endotoxemia, inflammation, and oxidative stress in patients with heart failure, left ventricular assist device, and transplant

BACKGROUND

Gut microbial imbalance may contribute to endotoxemia, inflammation, and oxidative stress in heart failure (HF). Changes occurring in the intestinal microbiota and inflammatory/oxidative milieu during HF progression and following left ventricular assist device (LVAD) or heart transplantation (HT) are unknown. We aimed to investigate variation in gut microbiota and circulating biomarkers of endotoxemia, inflammation, and oxidative stress in patients with HF (New York Heart Association, Class I-IV), LVAD, and HT.

METHODS

We enrolled 452 patients. Biomarkers of endotoxemia (lipopolysaccharide and soluble [sCD14]), inflammation (C-reactive protein, interleukin-6, tumor necrosis factor-α, and endothelin-1 adiponectin), and oxidative stress (isoprostane) were measured in 644 blood samples. A total of 304 stool samples were analyzed using 16S rRNA sequencing.

RESULTS

Gut microbial community measures of alpha diversity were progressively lower across worsening HF class and were similarly reduced in patients with LVAD and HT (p < 0.05). Inflammation and oxidative stress were elevated in patients with Class IV HF vs all other groups (all p < 0.05). Lipopolysaccharide was elevated in patients with Class IV HF (vs Class I-III) as well as in patients with LVAD and HT (p < 0.05). sCD14 was elevated in patients with Class IV HF and LVAD (vs Class I-III, p < 0.05) but not in patients with HT.

CONCLUSIONS

Reduced gut microbial diversity and increased endotoxemia, inflammation, and oxidative stress are present in patients with Class IV HF. Inflammation and oxidative stress are lower among patients with LVAD and HT relative to patients with Class IV HF, whereas reduced gut diversity and endotoxemia persist in LVAD and HT.

Novel Basic Science Insights to Improve the Management of Heart Failure: Review of the Working Group on Cellular and Molecular Biology of the Heart of the Italian Society of Cardiology

Despite important advances in diagnosis and treatment, heart failure (HF) remains a syndrome with substantial morbidity and dismal prognosis. Although implementation and optimization of existing technologies and drugs may lead to better management of HF, new or alternative strategies are desirable. In this regard, basic science is expected to give fundamental inputs, by expanding the knowledge of the pathways underlying HF development and progression, identifying approaches that may improve HF detection and prognostic stratification, and finding novel treatments. Here, we discuss recent basic science insights that encompass major areas of translational research in HF and have high potential clinical impact.

Effects of volume status on body composition in incident peritoneal dialysis patients

BACKGROUND

Inadequate fluid removal or high water intake leads to overhydration, which results in malnutrition. The aim of the present study was to evaluate the effects of volume status on body composition in incident peritoneal dialysis (PD) patients.

METHODS

All incident PD patients who survived ≥1 year after PD initiation were considered eligible. A total of 366 incident PD patients were finally included and divided into three tertiles according to the time-averaged-edema index (TA-EI). The body composition parameters measured using bioimpedance analysis included the EI, fat mass index (FMI, kg/m²), and appendicular muscle mass index (AMMI, kg/m²). dFMI and dAMMI were defined as delta values for each variable. The cutoff value for sarcopenia (SP) was defined as previously reported. Patients with AMMI below the cutoff values were defined as having SP.

RESULTS

The number of participants in the low, middle, and high tertiles was 126, 100, and 140, respectively. A high volume status was associated with high solute clearance, albumin loss, and glucose absorption through the peritoneal membrane, which led to high dialysate glucose. In addition, volume status was inversely associated with increases in AMMI, but was not associated with changes in FMI. SP as a categorical variable was positively associated with a high volume status. On subgroup analyses, TA-EI had the greatest negative correlation coefficients for dAMMI.

CONCLUSION

Overhydration in PD patients was associated with decrease in muscle mass indices and the development of SP.

Dietary metabolism, the gut microbiome, and heart failure

Advances in our understanding of how the gut microbiota contributes to human health and diseases have expanded our insight into how microbial composition and function affect the human host. Heart failure is associated with splanchnic circulation congestion, leading to bowel wall oedema and impaired intestinal barrier function. This situation is thought to heighten the overall inflammatory state via increased bacterial translocation and the presence of bacterial products in the systemic blood circulation. Several metabolites produced by gut microorganisms from dietary metabolism have been linked to pathologies such as atherosclerosis, hypertension, heart failure, chronic kidney disease, obesity, and type 2 diabetes mellitus. These findings suggest that the gut microbiome functions like an endocrine organ by generating bioactive metabolites that can directly or indirectly affect host physiology. In this Review, we discuss several newly discovered gut microbial metabolic pathways, including the production of trimethylamine and trimethylamine N-oxide, short-chain fatty acids, and secondary bile acids, that seem to participate in the development and progression of cardiovascular diseases, including heart failure. We also discuss the gut microbiome as a novel therapeutic target for the treatment of cardiovascular disease, and potential strategies for targeting intestinal microbial processes.

TAK-242, a specific inhibitor of Toll-like receptor 4 signalling, prevents endotoxemia-induced skeletal muscle wasting in mice

Circulating lipopolysaccharide (LPS) concentrations are often elevated in patients with sepsis or various endogenous diseases related to bacterial translocation from the gut. Systemic inflammatory responses induced by endotoxemia induce severe involuntary loss of skeletal muscle, termed muscle wasting, which adversely affects the survival and functional outcomes of these patients. Currently, no drugs are available for the treatment of endotoxemia-induced skeletal muscle wasting. Here, we tested the effects of TAK-242, a Toll-like receptor 4 (TLR4)-specific signalling inhibitor, on myotube atrophy in vitro and muscle wasting in vivo induced by endotoxin. LPS treatment of murine C2C12 myotubes induced an inflammatory response (increased nuclear factor-κB activity and interleukin-6 and tumour necrosis factor-α expression) and activated the ubiquitin-proteasome and autophagy proteolytic pathways (increased atrogin-1/MAFbx, MuRF1, and LC-II expression), resulting in myotube atrophy. In mice, LPS injection increased the same inflammatory and proteolytic pathways in skeletal muscle and induced atrophy, resulting in reduced grip strength. Notably, pretreatment of cells or mice with TAK-242 reduced or reversed all the detrimental effects of LPS in vitro and in vivo. Collectively, our results indicate that pharmacological inhibition of TLR4 signalling may be a novel therapeutic intervention for endotoxemia-induced muscle wasting.

Neopterin is Associated with Disease Severity and Outcome in Patients with Non-Ischaemic Heart Failure

Inflammation and immune activation play an important role in the pathogenesis of cardiac remodelling in patients with heart failure. The aim of this study was to assess whether biomarkers of inflammation and immune activation are linked to disease severity and the prognosis of heart failure patients. In 149 patients (65.8% men, median age 49.7 years) with heart failure from nonischaemic cardiomyopathy, the biomarkers neopterin and C-reactive protein were tested at the time of diagnosis. Patients were followed-up for a median of 58 months. During follow-up, nineteen patients died, five had a heart transplantation, two needed a ventricular assistance device, and twenty-one patients had to be hospitalised because of heart failure decompensation. Neopterin concentrations correlated with N-terminal prohormone of brain natriuretic peptide (NT-proBNP) concentrations (rs = 0.399, p < 0.001) and rose with higher New York Heart Association (NYHA) class (I: 5.60 nmol/L, II: 6.90 nmol/L, III/IV: 7.80 nmol/L, p = 0.033). Higher neopterin levels were predictive for an adverse outcome (death or hospitalisation due to HF decompensation), independently of age and sex and of established predictors in heart failure such as NYHA class, NT-proBNP, estimated glomerular filtration rate (eGFR), and left ventricular ejection fraction (LV-EF) (HR 2.770; 95% CI 1.419-5.407; p = 0.003). Patients with a neopterin/eGFR ratio ≥ 0.133 (as a combined marker for immune activation and kidney function) had a more than eightfold increased risk of reaching an endpoint compared to patients with a neopterin/eGFR ratio ≤0.065 (HR 8.380; 95% CI 2.889-24.308; p < 0.001). Neopterin is associated with disease severity and is an independent predictor of prognosis in patients with heart failure.

Extracellular-to-Intracellular Fluid Volume Ratio as a Prognostic Factor for Survival in Patients With Metastatic Cancer

Purpose: This study aimed to investigate whether the extracellular-to-intracellular fluid volume (E/I) ratio can predict survival in patients with metastatic cancer. Methods: Clinical data were collected from April 2016 to March 2018. Patients aged ≥19 years with metastatic solid tumor were eligible. Bioimpedance analysis was used to assess body fluid distribution and the E/I ratio. Clinical characteristics, including laboratory test results and nutrition status according to the E/I ratio, were analyzed. Cox proportional hazards models and Kaplan-Meier analysis were used to identify risk factors for mortality. Results: In total, 87 patients were included in the study. The 87 patients were divided into 2 groups according to the median E/I ratio: a high E/I group (E/I ratio ≥1.0, n = 43) and a low E/I group (E/I ratio <1.0, n = 44). Poor performance status, fluid retention, malnutrition, elevation of C-reactive protein levels, and decreases in hemoglobin, albumin, and protein levels were significantly associated with the high E/I group. The median overall survival time was 1.6 and 12.5 months in the high E/I and low E/I groups, respectively (P < .001). In the multivariate analysis, poor performance status, leukocytosis, fluid retention, and E/I ratio were independent prognostic factors, and the E/I ratio was the strongest prognostic factor predicting overall survival (hazard ratio = 3.49, 95% confidence interval = 1.75-6.96, P < .001). Conclusions: The E/I ratio can predict survival time in patients with metastatic cancer. More rigorous research is required to confirm this result.

The gut microbiome and heart failure: A better gut for a better heart

Despite the development of new drugs and therapeutic strategies, mortality and morbidity related to heart failure (HF) remains high. It is also the leading cause of global mortality. Several concepts have been proposed to explore the underlying pathogenesis of HF, but there is still a strong need for more specific and complementary therapeutic options. In recent years, accumulating evidence has demonstrated that changes in the composition of gut microbiota, referred to as dysbiosis, might play a pivotal role in the development of several diseases, including HF. HF-associated decreased cardiac output, resulting in bowell wall oedema and intestine ischaemia, can alter gut structure, peamibility and function. These changes would favour bacterial translocation, exacerbating HF pathogenesis at least partly through activation of systemic inflammation. Although our knowledge of the precise molecular mechanisms by which gut dysbiosis influance HF is still limited, a growing body of evidence has recently demonstrated the impact of a series of gut microbiome-derived metabolites, such as trimetylamine N-oxide, short-chain fatty acids or secondary bile acids, which have been shown to play critical roles in cardiac health and disease. This review will summarize the role of gut microbiota and its metabolites in the pathogenesis of HF. Current and future preventive and therapeutic strategies to prevent HF by an adequate modulation of the microbiome and its derived metabolites are also discussed.