Interleukin-6 and B-type natriuretic peptide are independent predictors for worsening of heart failure in patients with progressive congestive heart failure

Cardiovascular Biomarkers in Cardio-Oncology: Antineoplastic Drug Cardiotoxicity and Beyond

Serum biomarkers represent a reproducible, sensitive, minimally invasive and inexpensive method to explore possible adverse cardiovascular effects of antineoplastic treatments. They are useful tools in risk stratification, the early detection of cardiotoxicity and the follow-up and prognostic assessment of cancer patients. In this literature review, we aim at describing the current state of knowledge on the meaning and the usefulness of cardiovascular biomarkers in patients with cancer; analyzing the intricate relationship between cancer and cardiovascular disease (especially HF) and how this affects cardiovascular and tumor biomarkers; exploring the role of cardiovascular biomarkers in the risk stratification and in the identification of chemotherapy-induced cardiotoxicity; and providing a summary of the novel potential biomarkers in this clinical setting.

Inflammation in acute heart failure

Acute heart failure (AHF) represents a common clinical scenario that requires prompt evaluation and therapy and that is characterized by a high risk of mortality or subsequent rehospitalizations. The pathophysiology leading to AHF decompensation is still not fully understood. Significant activation of inflammatory pathways has been identified in patients with AHF, particularly in its most severe forms, and it has been hypothesized that systemic inflammation has a role in AHF pathogenesis. Several inflammatory mediators and cytokines, such as high sensitivity C-reactive protein, tumor necrosis factor-α, interleukin-6, interleukin-1, soluble suppression of tumorigenicity 2 and galectin-3, have been shown to play a role in the pathogenesis, development and worsening of this condition with an independent prediction of adverse outcomes. This manuscript reviews the prevalence and prognostic value of systemic inflammation in AHF, as well as the potential role of anti-inflammatory therapies, focusing on available evidence from clinical trials and ongoing studies.

The role of serial cardiac biomarkers in prognostication and risk prediction of chronic heart failure: additional scientific insights with hemodynamic feedback

INTRODUCTION

Heart failure (HF) is considered as a chronic long-term and lethal disease and will continue to be a major public health problem. Studying (circulating) biomarkers is a promising field of research and could be the first step toward HF tailored prognostic strategies as well as understanding the response to HF drugs in CHF patients.

AREAS COVERED

In literature, there has been considerable research on elevated biomarker levels that are related to a poor prognosis for HF. Since biomarker levels change over time, it is important to study serial (repeated) biomarker measurements which may help us better understand the dynamic course of HF illness. However, the majority of research focuses predominantly on baseline values of biomarkers. Additionally, remote monitoring devices, like sensors, can be used to link hemodynamic information to freshen biomarker data in order to further ameliorate the management of HF.

EXPERT OPINION

Novel biomarkers and additional scientific insights with hemodynamic feedback strongly aid in the prognostication and risk prediction of chronic HF.

Role of SARS-CoV-2-induced Cytokine Storm in Multi-Organ Failure: Molecular Pathways and Potential Therapeutic Options

Coronavirus disease 2019 (COVID-19) outbreak has become a global public health emergency and has led to devastating results. Mounting evidence proposes that the disease causes severe pulmonary involvement and influences different organs, leading to a critical situation named multi-organ failure. It is yet to be fully clarified how the disease becomes so deadly in some patients. However, it is proven that a condition called “cytokine storm” is involved in the deterioration of COVID-19. Although beneficial, sustained production of cytokines and overabundance of inflammatory mediators causing cytokine storm can lead to collateral vital organ damages. Furthermore, cytokine storm can cause post-COVID-19 syndrome (PCS), an important cause of morbidity after the acute phase of COVID-19. Herein, we aim to explain the possible pathophysiology mechanisms involved in COVID-19-related cytokine storm and its association with multi-organ failure and PCS. We also discuss the latest advances in finding the potential therapeutic targets to control cytokine storm wishing to answer unmet clinical demands for treatment of COVID-19.

Interleukin 6 and Development of Heart Failure With Preserved Ejection Fraction in the General Population

Background The cause of heart failure with preserved ejection fraction (HFpEF) is poorly understood, and specific therapies are lacking. Previous studies suggested that inflammation plays a role in the development of HFpEF. Herein, we aimed to investigate in community-dwelling individuals whether a higher plasma interleukin 6 (IL-6) level is associated with an increased risk of developing new-onset heart failure (HF) over time, and specifically HFpEF. Methods and Results We performed a case-cohort study based on the PREVEND (Prevention of Renal and Vascular End-Stage Disease) study, a prospective general population-based cohort study. We included 961 participants, comprising 200 participants who developed HF and a random group of 761 controls. HF with reduced ejection fraction or HFpEF was defined on the basis of the left ventricular ejection fraction of ≤40% or >40%, respectively. In Cox proportional hazard regression analyses, IL-6 levels were statistically significantly associated with the development of HF (hazard ratio [HR], 1.28; 95% CI, 1.02-1.61; P=0.03) after adjustment for key risk factors. Specifically, IL-6 levels were significantly associated with the development of HFpEF (HR, 1.59; 95% CI, 1.16-2.19; P=0.004), whereas the association with HF with reduced ejection fraction was nonsignificant (HR, 1.05; 95% CI, 0.75-1.47; P=0.77). In sensitivity analyses, defining HFpEF as left ventricular ejection fraction ≥50%, IL-6 levels were also significantly associated with the development of HFpEF (HR, 1.47; 95% CI, 1.04-2.06; P=0.03) after adjustment for key risk factors. Conclusions IL-6 is associated with new-onset HFpEF in community-dwelling individuals, independent of potential confounders. Our findings warrant further research to investigate whether IL-6 might be a novel treatment target to prevent HFpEF.

Reappraisal of Inflammatory Biomarkers in Heart Failure

PURPOSE OF REVIEW

Inflammation has been shown to be an important factor in the development and progression of heart failure (HF), regardless of the etiology. There have been many studies that demonstrated roles of inflammatory biomarkers in diagnosis, prognosis of chronic and acute HF patients, and also markers of cardiotoxicity from chemotherapy. These cytokines are high-sensitivity C-reactive protein (hsCRP), myeloperoxidase (MPO), soluble growth stimulation expressed gene 2 (sST2), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNFα), growth differentiation factor-15 (GDF-15), endothelin-1 (ET-1), and galectin-3. In this review, we discuss the past and present insights of those inflammatory biomarkers in order to gain more understanding in pathogenesis of HF, risk stratification of HF patients, and early detection of cardiotoxicity from cancer therapy.

RECENT FINDINGS

Many inflammatory cytokines have been shown to be associated with mortality of both chronic and acute HF patients, and some of them are able to track treatment responses, especially sST2 and galectin-3, which are the only two inflammatory biomarkers recommended to use in clinical setting by the recent standard HF guidelines, while some studies described ET-1 and MPO as potential predictors of cardiotoxicity from cancer drugs. The prognostic implications of inflammatory biomarkers in HF patients have been demonstrated more consistently in chronic than acute HF, with some suggestions of ET-1 and MPO in patients receiving chemotherapy. However, further studies are necessary for the use of inflammatory biomarkers in routine clinical practice.

The clinical significance of interleukin-6 in heart failure: results from the BIOSTAT-CHF study

AIMS

Inflammation is a central process in the pathophysiology of heart failure (HF), but trials targeting tumour necrosis factor (TNF)-α were largely unsuccessful. Interleukin (IL)-6 is an important inflammatory mediator and might constitute a potential pharmacologic target in HF. However, little is known regarding the association between IL-6 and clinical characteristics, outcomes and other inflammatory biomarkers in HF. We thus aimed to identify and characterize these associations.

METHODS AND RESULTS

Interleukin-6 was measured in 2329 patients [89.4% with a left ventricular ejection fraction (LVEF) ≤ 40%] of the BIOSTAT-CHF cohort. The primary outcome was all-cause mortality and HF hospitalization during 2 years, with all-cause, cardiovascular (CV), and non-CV death as secondary outcomes. Approximately half (56%) of all included patients had plasma IL-6 values greater than the previously determined 95th percentile of normal values at baseline. Elevated N-terminal pro-brain natriuretic peptide, procalcitonin and hepcidin, younger age, TNF-α/IL-1-related biomarkers, or having iron deficiency, atrial fibrillation and LVEF > 40% independently predicted elevated IL-6 levels. IL-6 independently predicted the primary outcome [HR (95% confidence interval) per doubling: 1.16 (1.11-1.21), P < 0.001], all-cause mortality [1.22 (1.16-1.29), P < 0.001] and CV as well as non-CV mortality [1.16 (1.09-1.24), P < 0.001; 1.31 (1.18-1.45), P < 0.001], but did not improve discrimination in previously published risk models.

CONCLUSIONS

In a large, heterogeneous cohort of HF patients, elevated IL-6 levels were found in more than 50% of patients and were associated with iron deficiency, reduced LVEF, atrial fibrillation and poorer clinical outcomes. These findings warrant further investigation of IL-6 as a potential therapeutic target in specific HF subpopulations.

Short Term Prognostic Value of the Rapid B-Type Natriuretic Peptide Assay on Length of Hospitalisation in Congestive Heart Failure Patients Presenting to an Emergency Department in Hong Kong: A Prospective Observational Study

Introduction

Congestive heart failure is a common disease presentation to the emergency department (ED) and most of these patients require hospitalisation for treatment. The aim of this study was to assess the predictive value of B-type natriuretic peptide (BNP) level measured at the ED with respect to the length of hospital stay (LOS) in patients presenting with congestive heart failure (CHF). We also compared whether the BNP level could be a better predictor of LOS than clinical parameters and attempted to establish a cut-off point of BNP level which could differentiate those CHF patients with short hospital stay from the whole population of CHF patients.

Method

Patients with clinical features compatible with congestive heart failure were recruited into the study. Point-of-care test for BNP level was performed. The LOS, 6-month readmission and mortality were retrieved from the computer Clinical Management System of the hospital. Pearson's correlation coefficient was used to test the association of BNP level and the LOS, 6-month readmission and mortality rate.

Result

One hundred and twelve (112) patients were recruited into this study and 20 of them succumbed during hospitalisation. The data of the remaining 92 patients were analysed. The correlation coefficient of BNP level and LOS was 0.088. The correlation coefficient of BNP level and readmission within 6 months was 0.130 while the correlation coefficient of BNP level and 6-month mortality was 0.121. The correlation coefficient of other clinical features and LOS ranged from −0.098 to 0.247. The mean LOS of patients with BNP less than 400 pg/ml was 93.29 hours (95%CI=57.38 to 129.19). The mean LOS of patients with BNP greater than 400 pg/ml was 181.05 hours (95%CI=126.01 to 236.08). Patients with BNP level less than 400 pg/ml tended to have a shorter LOS than those with BNP level greater than 400 pg/ml (p=0.046).

Conclusion

CHF patients with BNP level measured in the emergency department greater than 400 pg/ml tend to have a longer LOS than patients with BNP level less than 400 pg/ml. BNP is not a good predictor for readmission and mortality of these patients.

Microparticles in patients undergoing transcatheter aortic valve implantation (TAVI)

Degenerative aortic stenosis (AS) is the most frequent form of acquired valvular heart disease. AS is known to entail endothelial dysfunction caused by increased mechanical shear stress leading to elevated circulatory levels of microparticles. Endothelial and platelet microparticles (EMP and PMP) are small vesicles that originate from activated cells and thrombocytes. We sought to evaluate whether transcatheter aortic valve implantation (TAVI) procedure would elicit effects on circulating EMP and PMP. 92 patients undergoing TAVI procedure for severe AS were included in this study. Samples were obtained at each visit before TAVI, 1 week post-procedure and at 1, 3 and after 6 months after TAVI and were evaluated using flow cytometry. A 12 month clinical follow-up was also performed. CD62E+ EMP concentration before TAVI was 21.11 % (±6.6 % SD) and declined to 20.99 % (±6.8 % SD) after 1 week, to 16.63 % (±5.4 % SD, p < 0.0001) after 1 month, to 17.08 % (±4.6 % SD, p < 0.0001) after 3 months and to 15.94 % (±5.4 % SD, p < 0.0001) after 6 months. CD31+/CD42b-, CD31+/Annexin+/- EMP remained unchanged. CD31+/CD41b+ PMP evidenced a slight, but statistically significant increase after TAVI and remained elevated during the entire follow-up. Apart from a procedure-related improvement in echocardiographic parameters, TAVI procedure led also to a decline in CD62E+ EMP. The reduction in pressure gradients with less hemodynamic shear stress seems also to have beneficially affected endothelial homeostasis.

IL-18 stimulates B-type natriuretic peptide synthesis by cardiomyocytes in vitro and its plasma levels correlate with B-type natriuretic peptide in non-overloaded acute heart failure patients

BACKGROUND

An altered IL-18 pathway in heart failure (HF) has recently been described and this cytokine was shown to be of clinical and prognostic utility. Cardiomyocytes are a target of this cytokine which exerts inflammatory, hypertrophic, and profibrotic activities. B-type natriuretic peptide is a cardiac hormone produced in response to cardiac filling to regulate cardiovascular homeostasis. The aim of the study was to verify the ability of IL-18 to induce B-type natriuretic peptide synthesis in vitro and to analyse the relationship between these two molecules in plasma in vivo from acute HF patients.

METHODS AND RESULTS

We demonstrated the ability of IL-18 to directly stimulate a murine cardiomyocyte cell line to express the B-type natriuretic peptide gene, synthesize the relative protein through a PI3K-AKT-dependent transduction, and induce a cell secretory phenotype with B-type natriuretic peptide release. A correlation between IL-18 and B-type natriuretic peptide plasma levels was found in non-overloaded acute HF patients, and in subgroups of acute HF patients with diabetes and coronary artery disease. Acute HF patients with renal failure had significantly higher IL-18 plasma levels than patients without. IL-18 plasma levels were correlated with C-reactive protein plasma levels.

CONCLUSIONS

This study provides the first evidence of the ability of IL-18 to induce B-type natriuretic peptide synthesis in vitro and outlines the relationship between the two molecules in acute HF patients with an ongoing inflammatory status.

Are there differences in acute phase inflammation markers regarding the type of heart failure?

This study aimed to determine if there are differences in inflammatory markers in the acute phase between systolic heart failure and heart failure with preserved systolic function. One hundred and thirty-one patients with acute heart failure were recruited consecutively. At admission, plasma fibrinogen, C-reactive protein, sialic acid, von Willebrand factor, vascular endothelial growth factor, interleukin-6 and NTproBNP were all evaluated. If the ejection fraction was 45% or over patients were included in the HF-PSF group; the remaining patients were included in the SHF group. The HF-PSF patients were older (72±10 vs 63±12 years, P<0.001), presented a higher rate of atrial fibrillation (56.1 vs 21.3%, P<0.001), and had a lower rate of hemoglobin (12.2±2 vs 13.3±2.1 g/dL, P<0.01). No significant differences were observed in the inflammation markers analyzed among SHF and HF-PSF groups. In the acute phase of heart failure there is a marked elevation of inflammatory markers but there are no differences in the inflammatory markers analyzed between the two different types of heart failure.

Altered desmosomal proteins in granulomatous myocarditis and potential pathogenic links to arrhythmogenic right ventricular cardiomyopathy

BACKGROUND

Immunoreactive signal for the desmosomal protein plakoglobin (γ-catenin) is reduced at cardiac intercalated disks in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC), a highly arrhythmogenic condition caused by mutations in genes encoding desmosomal proteins. Previously, we observed a false-positive case in which plakoglobin signal was reduced in a patient initially believed to have ARVC but who actually had cardiac sarcoidosis. Sarcoidosis can masquerade clinically as ARVC but has not been previously associated with altered desmosomal proteins.

METHODS AND RESULTS

We observed marked reduction in immunoreactive signal for plakoglobin at cardiac myocyte junctions in patients with sarcoidosis and giant cell myocarditis, both highly arrhythmogenic forms of myocarditis associated with granulomatous inflammation. In contrast, plakoglobin signal was not depressed in lymphocytic (nongranulomatous) myocarditis. To determine whether cytokines might promote dislocation of plakoglobin from desmosomes, we incubated cultures of neonatal rat ventricular myocytes with selected inflammatory mediators. Brief exposure to low concentrations of interleukin (IL)-17, tumor necrosis factor-α (TNF-α), and IL-6 (cytokines implicated in granulomatous myocarditis) caused translocation of plakoglobin from cell-cell junctions to intracellular sites, whereas other potent cytokines implicated in nongranulomatous myocarditis had no effect, even at much higher concentrations. We also observed myocardial expression of IL-17 and TNF-α and elevated levels of serum inflammatory mediators, including IL-6R, IL-8, monocyte chemoattractant protein 1, and macrophage inflammatory protein 1β, in patients with ARVC (all P<0.0001 compared with controls).

CONCLUSIONS

The results suggest novel disease mechanisms involving desmosomal proteins in granulomatous myocarditis and implicate cytokines, perhaps derived in part from the myocardium, in disruption of desmosomal proteins and arrhythmogenesis in ARVC.

Interleukin-6 and tumor necrosis factor-alpha as biochemical markers of heart failure: a head-to-head clinical comparison with B-type natriuretic peptide

BACKGROUND

The reliability of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) as biochemical markers of heart failure in comparison to B-type natriuretic peptide (BNP) has not been investigated in depth.

AIM

To compare the correlations between IL-6, TNF, BNP plasma concentrations and some clinical and instrumental variables and their prognostic value in heart failure patients.

METHODS

In 79 patients with heart failure, the correlations between IL-6, TNF and BNP plasma concentrations and a series of 18 variables were studied. Outcome events were death from any cause and combined death and heart transplantation.

RESULTS

At univariate analysis, BNP and IL-6 plasma concentrations correlated with each other (r = 0.4828; P < 0.0001), with New York Heart Association class, fluid retention, left ventricular ejection fraction, mean right atrial pressure, mean pulmonary pressure and cardiac index. All these correlations were stronger with BNP. TNF plasma concentration correlated only with New York Heart Association class and left ventricular ejection fraction.During follow-up, 1-32 months, 14 patients died and nine underwent heart transplantation. At univariate analysis, both BNP and IL-6 plasma concentrations were predictors of death and heart transplantation, but only BNP was a predictor of death; however, only creatinine plasma level was an independent predictor of prognosis.

CONCLUSION

IL-6 and TNF are less reliable biochemical markers than BNP in heart failure patients.

Prognostic value of plasma midregional pro-adrenomedullin and C-terminal-pro-endothelin-1 in chronic heart failure outpatients

AIMS

The identification of chronic heart failure (CHF) patients at high risk of adverse outcome remains a challenge. New peptides are emerging that may give additional information. In CHF patients, endothelin (ET) levels predict mortality risk. Adrenomedullin has been shown to predict mortality in ischaemic heart failure, but not in unselected or non-ischaemic CHF patients. Moreover, ADM and ET have never been assessed in one model. The aim of the present study was to assess the prognostic value of midregional-pro-adrenomedullin (MR-proADM) and C-terminal-pro-endothelin-1 (CT-proET-1) in outpatients with CHF.

METHODS AND RESULTS

We measured plasma MR-proADM and CT-proET-1 levels in 786 consecutive CHF outpatients and compared them with B-type natriuretic peptide (BNP) levels. At 24-month follow-up, 233 patients had died. A stepwise forward Cox regression model with age, sex, estimated glomerular filtration rate, NYHA > II, left ventricular ejection fraction (LVEF), MR-proADM, CT-proET-1, and BNP as possible predictors revealed that MR-proADM levels [hazard ratio (HR) = 1.77, P < 0.001] in addition to age (HR = 1.02, P = 0.004), ejection fraction (HR = 0.98, P = 0.004), and NYHA > II (HR = 1.86, P < 0.001) were predictors of death at 24 months. When the analysis was repeated dependent on NYHA-stage, MR-proADM (HR = 2.12, P < 0.001) and LVEF (HR = 0.96, P = 0.006) were significant markers, but only in patients with mild/moderate CHF.

CONCLUSION

Our data suggest that MR-proADM may be an important prognostic humoral marker, especially in mild/moderately symptomatic and non-ischaemic CHF patients.

Novel metabolic risk factors for incident heart failure and their relationship with obesity: the MESA (Multi-Ethnic Study of Atherosclerosis) study

OBJECTIVES

The objectives of this study were to determine the associations of the metabolic syndrome, inflammatory markers, and insulin resistance with incident congestive heart failure (CHF), beyond established risk factors, and to examine whether these risk factors may provide the link between obesity and CHF.

BACKGROUND

Recently, increasing interest has emerged on the potential role of novel risk factors such as systemic inflammation, insulin resistance, and albuminuria in the pathophysiology of CHF and their relationship with obesity.

METHODS

The MESA (Multi-Ethnic Study of Atherosclerosis) study is a community-based multicenter cohort study of 6,814 participants (age 45 to 84 years, 3,601 women) of 4 ethnicities: Caucasians, African Americans, Hispanics, and Chinese Americans. Participants were recruited between 2000 and 2002 from 6 U.S. communities. Median follow-up time was 4 years. Participants with history of symptomatic cardiovascular disease were excluded. Cox proportional hazards models were used to analyze the associations of the metabolic syndrome, inflammatory markers, insulin resistance, and albuminuria with incident CHF, independent of established risk factors (age, gender, hypertension, diabetes mellitus, left ventricular hypertrophy, obesity, serum total cholesterol, and smoking), an interim myocardial infarction, and baseline magnetic resonance imaging parameters of left ventricular structure and function.

RESULTS

A total of 79 participants developed CHF during follow-up, and 26 participants (32.9%) had a myocardial infarction prior to CHF and 65% of the cases had CHF with preserved function (left ventricular ejection fraction >or=40%). In multivariable analyses, serum interleukin-6 (hazard ratio [HR] for 1 standard deviation 1.50, 95% confidence interval [CI] 1.10 to 2.03) or C-reactive protein (HR for 1 standard deviation 1.38; 95% CI 1.01 to 1.86) and macroalbuminuria (HR 4.31, 95% CI 1.58 to 11.76) were predictors of CHF, independent of obesity and the other established risk factors. Although obesity was significantly associated with incident CHF, this association was no longer significant after adding inflammatory markers (interleukin-6 or C-reactive protein) to the model.

CONCLUSIONS

Inflammatory markers and albuminuria are independent predictors of CHF. The association of obesity and CHF may be related to pathophysiologic pathways associated with inflammation.

Physical exercise improves plasmatic levels of IL-10, left ventricular end-diastolic pressure, and muscle lipid peroxidation in chronic heart failure rats

Chronic heart failure (CHF) is characterized by left ventricular dysfunction, resulting in hemodynamic changes, sustained inflammatory state, as well as increase in oxidative stress. Physical exercise has been described as an important nonpharmacological procedure in the treatment of CHF, contributing to the improvement of the clinical outcomes in this disease. This study evaluated the effects of physical training on hemodynamics, muscle lipid peroxidation, and plasmatic levels of IL-10 in CHF rats. The left coronary artery was ligated to induce CHF, or sham operation was performed in control groups. Rats were assigned to one of four groups: trained CHF (T-CHF, n = 10), sedentary CHF (S-CHF, n = 10), trained sham (T-Sham, n = 10), or sedentary sham (S-Sham, n = 10). Trained animals had carried out a swimming protocol, 60 min/day, 5 days/wk, during 8 wk, whereas sedentary animals remained without training. Eight weeks of physical training promoted an improvement of diastolic function represented by a reduction of the left ventricular end-diastolic pressure in the T-CHF group compared with the S-CHF group ( P < 0.05). Lipid peroxidation evaluated in gastrocnemius muscle using thiobarbituric acid reactive substance assay was higher in the S-CHF group compared with all other groups ( P < 0.05). However, there were no differences between T-CHF compared with S-Sham and T-Sham groups. The plasmatic levels of IL-10 were lower in the S-CHF group compared with all other groups ( P < 0.05). These findings demonstrate that regular physical training using a swimming protocol, with duration of 8 wk, improves the cardiac function and the anti-inflammatory response and reduces muscle cellular damage.

Risk stratification in neonates and infants submitted to cardiac surgery with cardiopulmonary bypass: a multimarker approach combining inflammatory mediators, N-terminal pro-B-type natriuretic peptide and troponin I

Low cardiac output syndrome (LCOS) is a common problem following cardiac surgery with cardiopulmonary bypass (CPB) in neonates and infants, and its early recognition remains a challenging task. We aimed to test whether a multimarker approach combining inflammatory and cardiac markers provides complementary information for prediction of LCOS and death in children submitted to cardiac surgery with CPB. Forty-six children younger than 18 months with congenital heart defects were prospectively enrolled. No intervention was made. Blood samples were collected pre-operatively, during CPB and post-operatively (PO) for measurement of interleukin (IL)-6, IL-8, IL-10, tumor necrosis factor (TNF)-alpha, cardiac troponin I (cTnI) and N-terminal pro-B-type natriuretic peptide (NT-proBNP). Clinical data and outcome variables were recorded. Logistic regression was used to identify predictors of LCOS and death. Multivariate logistic regression identified pre-operative NT-proBNP and IL-8 4h PO as independent predictors of LCOS, while cTnI 4h PO and CPB length were independent predictors of death. The use of inflammatory and cardiac markers in combination improved sensitivity, negative predictive value and accuracy of the models. In conclusion, the combined assessment of inflammatory and cardiac biochemical markers can be useful for identifying young children at increased risk for LCOS and death after heart surgery with CPB.

Relationship between CD40 ligand expression and B type natriuretic peptide levels in patients with chronic heart failure

BACKGROUND

Inflammation plays a pathogenic role in the development of chronic heart failure (CHF). Increasing evidence shows that CD40-CD40 ligand (CD40L) interaction plays a pathogenic role in inflammatory disorders. We assessed whether CD40 ligand expression was abnormal in patients with CHF.

METHODS

Twenty normal controls and 86 patients with CHF were investigated. The expression of CD40L on platelets was analyzed by indirect-immunofluorescence flow cytometry, and the soluble CD40L (sCD40L) level was determined by a commercially available enzyme-linked immunosorbent assay (ELISA). B type natriuretic peptide (BNP) was measured by radioimmunoassay.

RESULTS

All patients with CHF showed a significant increased expression of CD40L (32.3+/-13.9 MFI) on platelets and sCD40L levels (20.5+/-8.6 microg/l) compared with controls(p<0.0001). CD40L expression on platelets and sCD40L levels positively correlated with New York Heart Association (NYHA) functional class, left ventricular ejection fraction and BNP levels in CHF.

CONCLUSIONS

Patients with CHF showed increased expression of CD40L system, which may create a pathogenic role in the development and progression of CHF.

Atrial Natriuretic Peptide in Diabetic and Nondiabetic Patients With and Without Heart Transplantation

BACKGROUND

Natriuretic peptides are useful markers for risk stratification of patients with heart disease. However, conflicting results have been reported about circulating atrial natriuretic peptide (ANP) concentration in heart transplant recipients.

METHODS

To ascertain the effects of diabetes and acute insulin administration on plasma ANP concentrations in a model of heart denervation, we studied 12 diabetic (D-OHT) and 6 nondiabetic heart-transplanted (OHT) patients using the euglycemic-hyperinsulinemic clamp and oral glucose tolerance tests. Five patients with type 2 diabetes without heart transplantation (D) and 9 healthy subjects (NOR) matched for anthropometric features served as the controls.

RESULTS

Means baseline plasma ANP concentration was higher in D-OHT (82 +/- 15 pg/mL) than in OHT or NOR (27 +/- 4 or 30 +/- 5; P < .01), but was not different than D (69 +/- 12; P = .82). During the clamp plasma ANP showed similar increases in all groups (49 +/- 4, 39 +/- 3, 59 +/- 4, and 49 +/- 3% in D-OHT, OHT, D, and NOR; P < .02 vs basal, P = NS among groups). Plasma osmolarity and catecholamines were also not different among groups and did not increase during the clamp. Fasting plasma ANP concentrations correlated with plasma glucose concentrations measured 120 minutes after oral glucose tolerance testing.

CONCLUSIONS

Among heart transplantation recipients fasting plasma ANP concentrations were not different at 5 to 6 years after the surgical procedure than in nondiabetic controls. Increased ANP concentrations were observed among recipients with diabetes and among nontransplanted diabetic patients. Although the insulin-induced increment in ANP concentrations was not different among groups, circulating ANP was strongly associated with glucose tolerance status.

Restrictive Filling Pattern is a Powerful Predictor of Heart Failure Events Postacute Myocardial Infarction and in Established Heart Failure: A Literature-Based Meta-Analysis

BACKGROUND

Two recent literature-based meta-analyses revealed that restrictive filling pattern (RFP) was associated with a 4-fold increase in the risk of death in patients with heart failure (HF) and postacute myocardial infarction (AMI). This similar but unique analysis evaluated the link between RFP and morbidity.

METHODS AND RESULTS

Prospective echocardiographic studies of patients post-AMI and with HF that reported HF morbidity were identified. Events (post-AMI: development of HF; HF: HF readmission) were compared between patients with and without RFP in both patient groups. Review Manager version 4.2.7 software was used for the analysis. Twelve post-AMI studies (1286 patients, 271 events) and 5 HF studies (647 patients, 176 events) were identified. RFP was associated with HF readmission in the HF patients (OR 2.96 [2.02-4.33] and development of HF post-AMI (OR 10.10 [7.02-14.51]). The event rate in the RFP group was the same regardless of disease category (49% post-AMI, 42% HF); however, RFP was less prevalent in the post-AMI group (22% versus 39%).

CONCLUSIONS

This literature-based meta-analysis confirms that RFP is a powerful predictor of HF hospitalization in patients with HF and especially the development of HF post-AMI. This is an important prognostic sign and should be incorporated into routine clinical practice.

Novel and potential future biomarkers for assessment of the severity and prognosis of chronic heart failure

Over the last two decades, the pathophysiology and biomolecular basis of heart failure syndrome has reached sound and more comprehensive understanding. This knowledge has allowed expert researchers and clinicians to explore an entirely new spectrum of potential biochemical markers derived from different cellular and signaling pathways that lead to myocardial hypertrophy, chronic damage of the myocyte, apoptosis, and, ultimately, myocardial remodeling. Indeed, the link between myocardial remodeling and adverse outcomes, as well as the recognition of the myocardial interstitium as a multifunctional dynamic entity strongly influenced by systemic neurohormonal and inflammatory activation, has provided a solid ground for research of biomarkers that might correlate with severity and prognostication in chronic heart failure. This paper reviews and summarize recent literature on some of the most interesting circulating biomarkers with potential use for the stratification of patients with chronic heart failure.

Phenylarsine oxide inhibited beta-adrenergic receptor-mediated IL-6 secretion: inhibition of cAMP accumulation and CREB activation in cardiac fibroblasts

As we previously reported, cAMP and p38 MAPK instead of protein kinase A were involved in beta-adrenergic receptor (beta-AR)-mediated interleukin-6 (IL-6) production in mouse cardiac fibroblasts. Besides kinases, phosphatases may also be involved in IL-6 gene regulation. To study the role of protein tyrosine phosphatases (PTPs) in beta-AR-mediated IL-6 production, we selected the most widely used PTP inhibitor, phenylarsine oxide (PAO). We found that PAO dose-dependently inhibited the IL-6 release in response to beta-AR agonist isoproterenol (ISO) in mouse cardiac fibroblasts. This effect was probably due to the inhibition of PTPs, resulting in increased tyrosine phosphorylation, since genistein, an inhibitor of protein tyrosine kinases further potentiated ISO-induced IL-6 production and could partially reverse the inhibitory effect of PAO. PAO also significantly inhibited the IL-6 production by forskolin, an adenylyl cyclase (AC) activator. Furthermore, PAO dose-dependently inhibited the increased cAMP accumulation by either ISO or forskolin and suppressed the phosphorylation of CREB, an important transcriptional factor for IL-6 gene expression. But PAO did not affect the activation of p38 MAPK by ISO. Although PAO was also reported to inhibit NADPH oxidase, the inhibition of NADPH oxidase by its specific inhibitor, diphenylene iodonium (DPI) could not suppress beta-AR-mediated IL-6 production, suggesting that NADPH oxidase may not contribute to the inhibitory effect of PAO on IL-6 production. To our knowledge, this is the first report that PAO can inhibit ISO-induced IL-6 expression and CREB phosphorylation, demonstrating that PTPs may negatively regulate beta-AR-mediated IL-6 production. This study may also further our understanding of beta-AR signaling and provide potential therapeutic targets for the treatment of heart diseases.

The prognostic value of big endothelin-1 in more than 2,300 patients with heart failure enrolled in the Valsartan Heart Failure Trial (Val-HeFT)

BACKGROUND

Endothelin is elevated in heart failure and contributes to neurohormonal activation, hemodynamic deterioration, and cardiovascular remodeling. Here, we examined its prognostic value in a large population of patients with chronic heart failure.

METHODS AND RESULTS

Big endothelin-1 (Big ET-1) and 4 other neurohormones were measured at study entry in 2359 patients enrolled in the Valsartan Heart Failure Trial (Val-HeFT) and their concentrations related to outcome over a median follow-up of 23 months. Baseline concentration of Big ET-1 (median 0.80 pmol/L) was proportional to severity of disease (New York Heart Association class, left ventricular structure and function). High circulating concentrations of brain natriuretic peptide (BNP), creatinine and bilirubin, advanced New York Heart Association class, elevated body mass index, and the presence of atrial fibrillation were independently associated to higher concentrations of Big ET-1. Big ET-1 (ranking second just behind BNP among neurohormonal factors) was an independent predictor of outcome defined as all-cause mortality (hazard ratio 1.49, 95% CI 1.20-1.84, P = .0003) or the combined endpoint of mortality and morbidity (hazard ratio 1.43, 95% CI 1.20-1.69, P < .0001) and provided incremental prognostic value compared with BNP.

CONCLUSIONS

In a large population of patients with symptomatic heart failure, the circulating concentration of Big ET-1, a precursor of the paracrine and bioactive peptide ET-1, was an independent marker of mortality and morbidity. In this setting, BNP remained the strongest neurohormonal prognostic factor.

Canine nonischemic left ventricular dysfunction: a model of chronic human cardiomyopathy

BACKGROUND

The mechanisms of cardiac remodeling during chronic heart failure remain poorly defined. We sought to advance a chronic canine model of nonischemic cardiomyopathy.

METHODS AND RESULTS

Male dogs (n = 6) received decremental right ventricular apical tachypacing (12 months) to achieve and maintain stable left ventricular (LV) dysfunction. After 10 months of tachypacing, 120 beats/min was sufficient to maintain stable LV dysfunction. Electrocardiography, echocardiography, and tissue Doppler imaging were done to evaluate electrophysiology, LV dimensions and function, and dyssynchrony during normal sinus rhythm. The 6-minute walk test was used to evaluate functional capacity. We observed increases in both QRS duration (P < .0001) and QRS amplitude (P < .0001). LV fractional shortening was reduced from a baseline of 38.0 +/- 1.4% to 11.2 +/- 1.4% (P < .0001). LV end-diastolic dimension increased from 3.8 +/- 0.1 cm at baseline to 5.3 +/- 0.3 cm (P < .0001); LV end-systolic dimension increased from 2.3 +/- 0.1 cm to 4.7 +/- 0.2 cm (P < .0001). LV mass increased from 85.9 +/- 3.5 g at baseline to 179 +/- 13.7 g (P < .0001). There was evidence of LV dyssynchrony (P < .04) during both normal sinus rhythm and right ventricular tachypacing, compared with control dogs. The distance a dog walked in 6 minutes was significantly less at 12 months compared with normal controls (540 +/- 32 m versus 277 +/- 64 m, P < .008).

CONCLUSION

This nonischemic model of canine cardiomyopathy reproduces many aspects of chronic human heart failure including reduced fractional shortening, dilated ventricular dimensions, increased LV mass, decreased functional capacity, and dyssynchrony.

Natriuretic peptides as therapeutic targets

Natriuretic peptides (atrial natriuretic peptide, brain natriuretic peptide and C-type natriuretic peptide) are cardiac and vascular peptides with vasodilatory, diuretic, natriuretic, anti-inflammatory, antifibrotic and antimitogenic actions. Natriuretic peptides are implicated in normal pressure and volume homeostasis and in the defence against excessive increases in overload-related factors, vasopressive and cardiotoxic factors and their impact on the heart, blood vessels and brain. Genetic manipulation studies confirmed the importance of natriuretic peptides in these functions. Natriuretic peptides are metabolised by NPR-C (clearance receptors) and by enzymatic degradation by neutral endopeptidase. Natriuretic peptide levels (mainly brain natriuretic peptide) correlate with left ventricular hypertrophy and with the severity of heart failure, and are reduced by effective treatment, thus used as diagnostic and prognostic tools. Based on the multiple protective effects of natriuretic peptides, pharmacological therapy has been approved and includes potentiating natriuretic peptide levels by intravenous infusion or by inhibition of endogenous natriuretic peptide degradation. Because each approach has its limitations, the field remains open for improvement.

Comparison of Soluble Glycoprotein 130 and Cardiac Natriuretic Peptides as Long-term Predictors of Heart Failure Progression

BACKGROUND

In patients with heart failure, B-type natriuretic peptides (BNP, N-BNP) and atrial natriuretic peptide (ANP) are established prognostic markers. However, circulating interleukin (IL)-6-related cytokines and soluble glycoprotein 130 (sgp130), their common subunit for signal transduction, are also increased. We hypothesized that levels of circulating sgp130 and cardiac peptides provide independent prediction of worsening pump failure in the long term.

METHODS

A series of 76 patients (77% male, 54 ischemic and 17 nonischemic, left ventricular ejection fraction 22% +/- 7%) had blood samples drawn for assay of sgp130, oncostatin-M, N-ANP, N-BNP, and BNP. A composite end point of worsening pump failure (requiring hospitalization, intravenous therapy, or urgent heart transplantation) and pump failure death was used for follow-up.

RESULTS

During follow-up (up to 7 years), rate of worsening pump failure was 22.3%, including death. N-ANP (5666 +/- 3100 vs 7850 +/- 12164 fmol/ml), N-BNP (278 +/- 284 vs 250 +/- 297 pmol/ml), and oncostatin-M (15 +/- 28 vs 16 +/- 63 pg/ml) were similar in those who incurred worsening pump failure and in others. Mean sgp130 levels were 389 +/- 123 ng/ml in patients who developed worsening heart failure (Group A) and 289 +/- 123 ng/ml in stable patients (Group B; p < 0.0001). Mean BNP was 567 +/- 774 pg/ml in Group A and 307 +/- 324 pg/ml in Group B (p < 0.05). By using a cutoff value of 286 ng/ml for gp130 in Kaplan-Meier analysis, we found that the rate of freedom from worsening heart failure was significantly higher in patients below compared with patients above this cutoff point (p = 0.03). In univariate and multivariate Cox regression analysis, only sgp130 emerged as statistically significant (p < 0.001).

CONCLUSIONS

In addition to BNP, sgp130 could be useful in identifying patients at high risk for heart failure progression.

Interleukin-6 Causes Myocardial Failure and Skeletal Muscle Atrophy in Rats

Background— The impact of interleukin (IL)-6 on skeletal muscle function remains the subject of controversy.

Methods and Results— The effects of 7-day subcutaneous administration of recombinant human IL-6 were examined at 3 doses, 50, 100, or 250 μg · kg −1 · d −1 , in rats. Skeletal muscle mass decreased dose-dependently (with increasing dose: in the diaphragm, −10%, P =NS; −15%, P =0.0561; and −15% P <0.05; and in the gastrocnemius, −9%, P =NS; −9%, P =NS; and −18%, P <0.005) because of decreases in cross-sectional area of all fiber types without alterations in diaphragm contractile properties. Cardiovascular variables showed a dose-dependent heart dilatation (for end-diastolic volume: control, 78 μL; moderate dose, 123 μL; and high dose, 137 μL, P <0.001), reduced end-systolic pressure (control, 113 mm Hg; moderate dose, 87 mm Hg; and high dose, 90 mm Hg; P =0.037), and decreased myocardial contractility (for preload recruitable stroke work: control, 79 mm Hg; moderate dose, 67 mm Hg; and high dose, 48 mm Hg; P <0.001). Lung edema was confirmed by an increased wet-to-dry ratio (control, 4.2; moderate dose, 4.6; and high dose, 4.5; P <0.001) and microscopy findings. These cardiovascular alterations led to decreases in organ blood flow, particularly in the diaphragm (control, 0.56 mL · min −1 · g −1 ; moderate dose, 0.21 mL · min −1 · g −1 ; and high dose, 0.23 mL · min −1 · g −1 ; P =0.037). In vitro recombinant human IL-6 administration did not cause any alterations in diaphragm force or endurance capacity.

Conclusions— IL-6 clearly caused ventilatory and peripheral skeletal muscle atrophy, even after short-term administration. Blood flow redistribution, resulting from the myocardial failure induced by IL-6, was likely responsible for this muscle atrophy, because IL-6 did not exert any direct effect on the diaphragm.

Brain natriuretic peptide in the contemporary management of congestive heart failure

Brain natriuretic peptide is a cardiac neurohormone that is secreted by the left ventricle in response to an increase in wall stress. Brain natriuretic peptide has emerged as a neurohormone with multiple roles in heart failure management. This review will discuss the role of brain natriuretic peptide in heart failure diagnosis, prognostic assessment, screening for asymptomatic left-ventricular dysfunction, and in the treatment of heart failure.