Haemodynamic, neuroendocrine and metabolic correlates of circulating cytokine concentrations in congestive heart failure

Redox state of human serum albumin as a post-discharge prognostic marker in patients hospitalized for heart failure

BACKGROUND

Heart failure (HF) is a global health concern, and oxidative stress has been implicated in its progression. The redox state of human serum albumin, a systemic oxidative biomarker, holds promise as a prognostic marker in HF. This study aimed to investigate the association between the fraction of human mercaptalbumin (fHMA), an indicator of human serum albumin's redox state, and adverse events in HF within a prospective single-hospital-based cohort.

METHODS

We enrolled patients hospitalized for HF and measured fHMA using high-performance liquid chromatography at discharge. The primary endpoint was the composite of HF rehospitalization and all-cause death within one year after discharge.

RESULTS

A total of 221 participants (median age:79 years; 35 % female) were included in the study. Over the course of one year, 26.1 % of the patients experienced HF readmission, while 13.1 % died. The low fHMA group divided by median of fHMA (<57.6 %) showed higher composite outcome rates (41.4 % for the low fHMA vs. 24.6 % for the high fHMA, p = 0.0114). Multivariate analysis, accounting for seven potential confounders, identified low fHMA (adjusted HR: 1.79 [1.03-3.11]) and lower hemoglobin as independent predictors of HF prognosis.

CONCLUSIONS

The findings in this study provide the first evidence that fHMA is a potential novel prognostic biomarker in patients with HF.

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

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

Augmentation of natriuretic peptide (NP) receptor A and B (NPR-A and NPR-B) and cyclic guanosine monophosphate (cGMP) signalling as a therapeutic strategy in heart failure

INTRODUCTION

Heart failure is a complex, debilitating condition and despite advances in treatment, it remains a significant cause of morbidity and mortality worldwide. Therefore, the need for alternative treatment strategies is essential. In this review, we explore the therapeutic strategies of augmenting natriuretic peptide receptors (NPR-A and NPR-B) and cyclic guanosine monophosphate (cGMP) in heart failure.

AREAS COVERED

We aim to provide an overview of the evidence of preclinical and clinical studies on novel heart failure treatment strategies. Papers collected in this review have been filtered and screened following PubMed searches. This includes epigenetics, modulating enzyme activity in natriuretic peptide (NP) synthesis, gene therapy, modulation of downstream signaling by augmenting soluble guanylate cyclase (sGC) and phosphodiesterase (PDE) inhibition, nitrates, c-GMP-dependent protein kinase, synthetic and designer NP and RNA therapy.

EXPERT OPINION

The novel treatment strategies mentioned above have shown great potential, however, large randomized controlled trials are still lacking. The biggest challenge is translating the results seen in preclinical trials into clinical trials. We recommend a multi-disciplinary team approach with cardiologists, geneticist, pharmacologists, bioengineers, researchers, regulators, and patients to improve heart failure outcomes. Future management can involve telemedicine, remote monitoring, and artificial intelligence to optimize patient care.

Cyclic GMP and PKG Signaling in Heart Failure

Cyclic guanosine monophosphate (cGMP), produced by guanylate cyclase (GC), activates protein kinase G (PKG) and regulates cardiac remodeling. cGMP/PKG signal is activated by two intrinsic pathways: nitric oxide (NO)-soluble GC and natriuretic peptide (NP)-particulate GC (pGC) pathways. Activation of these pathways has emerged as a potent therapeutic strategy to treat patients with heart failure, given cGMP-PKG signaling is impaired in heart failure with reduced ejection fraction (HFrEF) and preserved ejection fraction (HFpEF). Large scale clinical trials in patients with HFrEF have shown positive results with agents that activate cGMP-PKG pathways. In patients with HFpEF, however, benefits were observed only in a subgroup of patients. Further investigation for cGMP-PKG pathway is needed to develop better targeting strategies for HFpEF. This review outlines cGMP-PKG pathway and its modulation in heart failure.

Uni-ventricular palliation vs. bi-ventricular repair: differential inflammatory response

Background

To examine whether uni-ventricular palliation (UVP) and bi-ventricular repair (BVR) result in a different pattern of systemic inflammatory response to pediatric cardiac surgery with extra-corporeal circulation (ECC).

Methods

In 20 children (median age 39.5 months) undergoing either UVP (n = 12) or BVR (n = 8), plasma levels of the inflammatory cytokines TNF-α, IL-6, IL-10, and IL-12 and of procalcitonin (PCT), were measured before, during and after open cardiac surgery up to postoperative day (POD) 10.

Results

Epidemiologic, operative- and outcome variables were similar in both groups but post-operative central venous pressure that was higher in UVP. In the whole cohort, the inflammatory response was characterized by an early important, significant and parallel increase of IL-6 and IL-10 that reached their peak values either at the end of ECC (IL-10) or 4 h postoperatively (IL-6), respectively and by a significant and parallel decrease of TNF-α and IL-12 levels after connection to ECC, followed by a bi-phasic significant increase with a first peak 4 h after ECC and a second at POD 10, respectively. Patients after UVP showed a shift of the cytokine balance with lower IL-6- (p = 0.01) after connection to ECC, lower early post-operative TNF-α - (p = 0.02) and IL-12- (p = 0.04) concentrations and lower TNF-α/IL-10-ratio (p = 0.03) as compared with patients with BVR. Levels of PCT were similar in both groups.

Conclusions

UVP is associated with an anti-inflammatory shift of the inflammatory response to cardiac surgery that might be related to the particular hemodynamic situation of patients with UVP.

Oxidative stress and inflammation in the evolution of heart failure: From pathophysiology to therapeutic strategies

Both oxidative stress and inflammation are enhanced in chronic heart failure. Dysfunction of cardiac mitochondria is a hallmark of heart failure and a leading cause of oxidative stress, which in turn exerts detrimental effects on cellular components, including mitochondria themselves, thus generating a vicious circle. Oxidative stress also causes myocardial tissue damage and inflammation, contributing to heart failure progression. Furthermore, a subclinical inflammatory state may be caused by heart failure comorbidities such as obesity, diabetes mellitus or sleep apnoeas. Some markers of both oxidative stress and inflammation are enhanced in chronic heart failure and hold prognostic significance. For all these reasons, antioxidants or anti-inflammatory drugs may represent interesting additional therapies for subjects either at high risk or with established heart failure. Nonetheless, only a few clinical trials on antioxidants have been carried out so far, with several disappointing results except for vitamin C, elamipretide and coenzyme Q10. With regard to anti-inflammatory drugs, only preliminary data on the interleukin-1 antagonist anakinra are currently available. Therefore, a comprehensive, deep understanding of our current knowledge on oxidative stress and inflammation in chronic heart failure is key to providing some suggestions for future research on this topic.

Promising utilization areas of therapeutic plasmapheresis in cardiovascular surgery practice

OBJECTIVE

Apheresis is performed for treatment of numerous diseases by removing auto-antibodies, antigen-antibody complexes, allo-antibodies, paraproteins, non-Ig proteins, toxins, exogenous poisons. In current study, we present our experience of using therapeutic plasma exchange (TPE) in patients with different types of clinical scenarios.

METHODS

Between January 2013 and May 2016, we retrospectively presented the results of 64 patients in whom postoperative TPE was performed in ICU setting after cardiac surgery. Patients were grouped into four as; 1-sepsis (n = 26), 2-hepatorenal syndrome(n = 24), 3-antibody mediated rejection(AMR) following heart transplantation(n = 4) and 4-right heart failure(RHF) after left ventricular asist device(LVAD)(n = 10). Hemodynamic parameters were monitored constantly, pre- and post-procedure peripheral blood tests including renal and liver functions and daily complete blood count (CBC), sedimentation, C-reactive protein and procalcitonin (ng/ml) levels were studied.

RESULTS

The mean age was 61 ± 17.67 years old and 56.25% (n = 36) were male. Mean Pre TPE left ventricular ejection fraction (LVEF) (%), central venous pressure (CVP)(mmHg) pulmonary capillary wedge pressure (PCWP)(mmHg) and pulmonary arterial pressure (PAP)(mmHg) were measured as 41.8 ± 8.1, 15.5 ± 4.4, 17.3 ± 3.24 and 39.9 ± 5.4, respectively. Procalcitonin (ng/ml) level of patients undergoing TPE due to sepsis was significantly reduced from 873 ± 401 ng/ml to 248 ± 132 ng/ml. Seventeen (26.5%) patients died in hospital during treatment, mean length of intensive care unit (ICU) stay(days) was 13.2 ± 5.1.

CONCLUSION

This study shows that TEP is a safe and feasible treatment modality in patients with different types of complications after cardiac surgery and hopefully this study will lead to new utilization areas.

High-density lipoprotein-associated paraoxonase-1 activity for prediction of adverse outcomes in outpatients with chronic heart failure

AIMS

Decreased arylesterase (ArylE) activity of paraoxonase-1, a HDL-associated protein with anti-inflammatory and antioxidant properties, has been associated with increased risk of cardiac events in patients with ischaemic heart failure (HF). We aim to investigate the prognostic significance of changes in serum ArylE activity over time.

METHODS AND RESULTS

We examined the association between baseline and follow-up serum ArylE activity and HF outcomes (death, cardiac transplantation, or ventricular assist device implantation) in 299 patients with HF enrolled in a prospective cohort study from January 2008 to July 2009, with 145 patients having available follow-up levels at 1 year. A significant drop in ArylE activity on follow-up was defined as a drop of ≥25% vs. baseline levels. Mean baseline and follow-up ArylE activity levels were 110.6 ± 29.9 µmol/min/mL and 106.2 ± 29.9 µmol/min/mL, respectively. After a mean follow-up of 2.8 ± 1.1 years, low baseline ArylE activity was associated with increased risk of adverse HF events [hazard ratio (HR; lowest vs highest tertile) 2.6, 95% confidence interval (CI) 1.3-5.5, P = 0.01] and HF-related hospitalization [incidence rate ratio (lowest vs. highest tertile) 2.1, 95% CI 1.2-4.1, P = 0.016], which remained significant after adjustment for age, male gender, systolic blood pressure, diabetes, creatinine clearance, CAD, and HDL-cholesterol levels. Patients who had a significant drop in ArylE activity on follow-up (n = 18) had a significantly increased risk of HF events (HR 4.9, 95% CI 1.6-14.6, P = 0.005), even after adjustment for baseline levels of ArylE activity.

CONCLUSIONS

Reduced baseline ArylE activity and decreased levels on follow-up are associated with adverse outcomes in stable outpatients with HF.

ECG low QRS voltage and wide QRS complex predictive of centenarian 360-day mortality

We examined the electrocardiographic (ECG) findings of centenarians and associated them with >360-day survival. Physical and functional assessment, resting electrocardiogram and laboratory tests were performed on 86 study participants 101.9 ± 1.2 years old (mean ± SD) (70 women, 16 men) and followed for at least 360 days. Centenarian ECGs were assessed for left ventricular hypertrophy (LVH) according to the Romhilt-Estes score, Sokolow-Lyon criteria and Cornell voltage criteria which were positive for 12.8, 6.98, and 10.5 % of participants, respectively. Fifty-two study participants (60 %) survived ≥360 days. Multivariate logistic regression analysis revealed a negative relationship between 360-day survival and the following: R II <0.45 mV adjusted for CRP (odds ratio (OR) = 0.108, 95 % confidence interval (CI) = 0.034-0.341, P < .001), R aVF < 0.35 mV adjusted for CRP (OR = 0.151, 95 % CI = 0.039-0.584, P < .006), Sokolow-Lyon voltage <1.45 mV adjusted for CRP (OR = 0.178, 95 % CI = 0.064-0.492, P = .001), QRS ≥90 ms adjusted for CRP (OR = 0.375, 95 % CI = 0.144-0.975, P = .044), and Romhilt-Estes score ≥5 points adjusted for sex and Barthel Index (OR = 0.459, 95 % CI = 0.212-0.993, P = .048) in single variable ECG models. QRS voltage correlated positively with systolic and pulse pressure, serum vitamin B12 level, sodium, calcium, phosphorous, TIMP-1, and eGFR. QRS voltage correlated negatively with BMI, WHR, serum leptin, IL-6, TNF-α, and PAI-1 levels. QRS complex duration correlated positively with CRP; QTc correlated positively with TNF-α. Results suggest that Romhilt-Estes LVH criteria scores ≥5 points, low ECG QRS voltages (Sokolow-Lyon voltage <1.45 mV), and QRS complexes ≥90 ms are predictive of centenarian 360-day mortality.

Role played by interleukin-6 in evoking the exercise pressor reflex in decerebrate rats: effect of femoral artery ligation

IL-6 signaling via the soluble IL-6 receptor (sIL-6r) has been shown to increase primary afferent responsiveness to noxious stimuli. This finding prompted us to test the hypothesis that IL-6 and sIL-6r would increase the exercise pressor reflex in decerebrate rats with freely perfused femoral arteries. We also tested the hypothesis that soluble glycoprotein (sgp)130, an inhibitor of IL-6/sIL-6r signaling, would decrease the exaggerated exercise pressor reflex that is found in decerebrate rats with ligated femoral arteries. In rats with freely perfused femoral arteries, coinjection of 50 ng of IL-6 and sIL-6r into the arterial supply of the hindlimb significantly increased the peak pressor response to static (control: 14 ± 3 mmHg and IL-6/sIL-6r: 17 ± 2 mmHg, P = 0.03) and intermittent isometric (control: 10 ± 2 mmHg and IL-6/sIL-6r: 15 ± 4 mmHg, P = 0.03) hindlimb muscle contraction. In rats with ligated femoral arteries, injection of 50 ng of sgp130 into the arterial supply of the hindlimb reduced the peak pressor response to static (control: 24 ± 2 mmHg and sgp130: 16 ± 3 mmHg, P = 0.01) and intermittent isometric (control: 16 ± 2 mmHg and sgp130: 13 ± 2 mmHg, P = 0.04) hindlimb muscle contraction, whereas there was no effect of sgp130 on the exercise pressor reflex in rats with freely perfused femoral arteries. We conclude that coinjection of exogenous IL-6 and sIL-6r increased the exercise pressor reflex in rats with freely perfused femoral arteries. More importantly, we also conclude that IL-6 and sIL-6r play an endogenous role in evoking the exercise pressor reflex in rats with ligated femoral arteries but not in rats with freely perfused femoral arteries.

A novel paradigm for heart failure with preserved ejection fraction: comorbidities drive myocardial dysfunction and remodeling through coronary microvascular endothelial inflammation

Over the past decade, myocardial structure, cardiomyocyte function, and intramyocardial signaling were shown to be specifically altered in heart failure with preserved ejection fraction (HFPEF). A new paradigm for HFPEF development is therefore proposed, which identifies a systemic proinflammatory state induced by comorbidities as the cause of myocardial structural and functional alterations. The new paradigm presumes the following sequence of events in HFPEF: 1) a high prevalence of comorbidities such as overweight/obesity, diabetes mellitus, chronic obstructive pulmonary disease, and salt-sensitive hypertension induce a systemic proinflammatory state; 2) a systemic proinflammatory state causes coronary microvascular endothelial inflammation; 3) coronary microvascular endothelial inflammation reduces nitric oxide bioavailability, cyclic guanosine monophosphate content, and protein kinase G (PKG) activity in adjacent cardiomyocytes; 4) low PKG activity favors hypertrophy development and increases resting tension because of hypophosphorylation of titin; and 5) both stiff cardiomyocytes and interstitial fibrosis contribute to high diastolic left ventricular (LV) stiffness and heart failure development. The new HFPEF paradigm shifts emphasis from LV afterload excess to coronary microvascular inflammation. This shift is supported by a favorable Laplace relationship in concentric LV hypertrophy and by all cardiac chambers showing similar remodeling and dysfunction. Myocardial remodeling in HFPEF differs from heart failure with reduced ejection fraction, in which remodeling is driven by loss of cardiomyocytes. The new HFPEF paradigm proposes comorbidities, plasma markers of inflammation, or vascular hyperemic responses to be included in diagnostic algorithms and aims at restoring myocardial PKG activity.

Intrinsic skeletal muscle alterations in chronic heart failure patients: a disease-specific myopathy or a result of deconditioning?

Chronic heart failure (CHF) patients frequently experience impaired exercise tolerance due to skeletal muscle fatigue. Studies suggest that this in part is due to intrinsic alterations in skeletal muscle of CHF patients, often interpreted as a disease-specific myopathy. Knowledge about the mechanisms underlying these skeletal muscle alterations is of importance for the pathophysiological understanding of CHF, therapeutic approach and rehabilitation strategies. We here critically review the evidence for skeletal muscle alterations in CHF, the underlying mechanisms of such alterations and how skeletal muscle responds to training in this patient group. Skeletal muscle characteristics in CHF patients are very similar to what is reported in response to chronic obstructive pulmonary disease (COPD), detraining and deconditioning. Furthermore, skeletal muscle alterations observed in CHF patients are reversible by training, and skeletal muscle of CHF patients seems to be at least as trainable as that of matched controls. We argue that deconditioning is a major contributor to the skeletal muscle dysfunction in CHF patients and that further research is needed to determine whether, and to what extent, the intrinsic skeletal muscle alterations in CHF represent an integral part of the pathophysiology in this disease.

Immune modulation in heart failure: past challenges and future hopes

Immune-modulation therapy has had great success in various inflammatory diseases. Despite the promising results of preliminary studies in anti-tumor necrosis factor-α therapies, large randomized studies have lacked positive clinical outcomes in patients with heart failure. These results have led to the idea that therapies directed toward specific inflammatory mediators may not be the answer and lead us toward the development of novel anti-inflammatory strategies that may involve a broader spectrum of inflammatory mediators. Therapeutic plasma exchange has been demonstrated as a safe treatment, and preliminary outcomes led us to develop new treatment schemes.

Cystatin C, NT-proBNP, and inflammatory markers in acute heart failure: insights into the cardiorenal syndrome

BACKGROUND

Inflammation is thought to be a mediator in the pathophysiology of the cardiorenal syndrome. We evaluated the interactions between kidney function, cardiac stress, and various inflammatory cytokines in patients with acute heart failure (AHF). The effect on 1-year mortality was also assessed.

METHODS AND RESULTS

Plasma levels of cystatin C, NT-proBNP, and inflammatory cytokines (interleukin [IL]-6, tumor necrosis factor-α [TNF-α], IL-10) were measured in consecutive patients (n = 465) hospitalized for AHF. After adjustment for demographic characteristics and comorbidities, TNF-α had the strongest relation with renal function (β = 0.39, P < 0.0001). Elevated TNF-α levels were seen in patients with high cystatin C, irrespective of NT-proBNP. Levels of IL-6 (β = 0.26, P < 0.0001) and IL-10 (β = 0.15, P < 0.01), but not TNF-α, were associated with NT-proBNP. Moreover, the most elevated levels of IL-6 were seen in patients with combined high NT-proBNP and high cystatin C. Cox regression analysis found IL-6 above median to be independently predictive of mortality (hazard ratio 1.9; 95% CI 1.2-2.9, P = 0.003). TNF-α was not significantly associated with prognosis in the overall population after adjustment for multiple covariates, but improved risk stratification in the subgroup with low cystatin C and NT-proBNP.

CONCLUSION

Levels of TNF-α in AHF are related to kidney function, but not to NT-proBNP. IL-6 seems to be more associated with cardiac stress. Patients with severe dual organ dysfunction have the highest levels of IL-6 and TNF-α. Different relations of inflammatory cytokines to renal function and cardiac stress need to be considered when evaluating heart--kidney interactions.

Circulating cytokine levels in mice with heart failure are etiology dependent

Objectives: The aim of this study was to examine whether alterations in circulating cytokine levels are dependent on the etiology of myocardial hypertrophy and heart failure (HF). Background: Several heart diseases are associated with altered levels of circulating cytokines. Cytokines are regarded as possible therapeutic targets or biomarkers, but such approaches are currently not in clinical use. If alterations in circulating cytokines are etiology dependent, this should be taken into consideration when using cytokines as disease markers and therapeutic targets. Methods: The serum levels of 25 cytokines were quantified with Luminex and/or ELISA in four murine models of heart disease: banding of the ascending aorta (AB) or the pulmonary artery (PB), myocardial infarction (MI), and a cardiomyopathy model with inducible cardiomyocyte-specific knockout of the sarco(endo)plasmatic reticulum Ca2+-ATPase (SERCA2KO). Results: No increase in circulating cytokine levels were found in mice 1 wk after AB, although substantial myocardial hypertrophy was present. After 1 wk of MI, only interleukin (IL)-18 was increased. In the SERCA2KO mice with HF, circulating levels of IL-1α, IL-2, IL-3, IL-6, IL-9, IL-10, IL-12p40, eotaxin, granulocyte-colony stimulating factor (G-CSF), interferon-γ, monocyte chemoattractant protein-1, macrophage inflammatory protein-1β were increased, and in mice with PB, IL-1α, IL-6, G-CSF, and monokine induced by gamma-interferon showed elevated levels. Conclusions: Serum levels of cytokines in mice with HF vary depending on the etiology. Increased serum levels of several cytokines were found in models with increased right ventricular afterload, suggesting that the cytokine responses result primarily from systemic congestion.

Is interleukin-22 a possible indicator of chronic heart failure's progression?

Chronic heart failure (CHF) is a complex and heterogeneous clinical syndrome and because of its rising incidence and prevalence, it can be considered a global epidemic. Interleukin (IL)-22 is a pro-inflammatory cytokine, belonging to the IL-10 family. Forty-seven consecutive older patients, hospitalized with an admitting diagnosis of CHF at the Geriatric Medicine Unit (University of Messina, Italy), from 01/01/06 to 30/06/06, were enrolled in the study. Serum concentrations of IL-22 were measured by a quantitative enzyme immunoassay technique. IL-22 levels in all CHF patients were significantly higher than those in controls, in particular, only the II and III NYHA class had IL-22 values significantly higher than the controls, whereas there was no difference between the IL-22 levels of NYHA class IV and the controls. The reason may be the declining immune function in CHF older patients, in fact we can hypothesize that the fall in IL-22 levels, with the progression of NYHA class, is due to the reduced ability in CHF patients to respond to infections, as IL-22 has anti-microbial properties. We detected different outcomes correlated to different IL-22 levels, and the Kaplan-Meier curves suggest a trend.

The role of exercise on L-arginine nitric oxide pathway in chronic heart failure

Chronic heart failure (CHF) is a pathological state with high morbidity and mortality and the full understanding of its genesis remain to be elucidated. In this syndrome, a cascade of neurohormonal and hemodynamic mechanisms, as well as inflammatory mediators, are activated to improve the impaired cardiac function. Clinical and experimental observations have shown that CHF is associated with a generalized disturbance in endothelium-dependent vasodilation, which may contribute to the progression of ventricular and vascular remodelling in this syndrome. There is also accumulating evidence that disturbances in nitric oxide (NO) availability is involved in the development of heart failure at the systemic and cardiac levels. NO is a ubiquitous signalling molecule which causes potent vasodilation, inhibits platelet activation and regulates the contractile properties of cardiac myocytes. It is generated from the amino acid L-arginine via constitutive and inducible isoforms of the enzyme NO synthase (NOS). There is evidence that exercise, a nonpharmacological tool, improves symptoms, fitness (VO_2peak), quality of life and NO bioavailability in CHF population. This review examines different aspects of the L-arginine-NO pathway and inflammation in the physiopathology of CHF and highlights the important beneficial effects of exercise in this disease.

Cytokines and matrix metalloproteinases as potential biomarkers in chronic heart failure

Heart failure (HF) is accompanied by the upregulation of bioactive signaling molecules, known as cytokines, and a family of downstream proteases, matrix metalloproteinases (MMPs). It is now apparent that these molecules contribute to adverse myocardial remodeling during HF. Elevated levels of cytokines and MMPs exist in the myocardium and can subsequently spill over into the systemic circulation. The purpose of this article is to examine clinical studies of HF that have quantified levels of different types of cytokines, MMPs and endogenous tissue inhibitors of MMPs in relation to this disease process. HF is a complex syndrome that can develop from various etiologies and can be characterized into two distinct phenotypes: systolic and diastolic. This article will present recent clinical studies that have identified significant differences between the cytokine and MMP circulating profile of systolic and diastolic HF patients. In general, elevated levels of cytokines and MMPs exist in systolic HF patients when compared with diastolic HF patients, whereas diastolic HF patients have elevated levels of cytokines and MMPs when compared with controls. Therefore, future studies distinguishing between HF phenotypes may provide more consistent results in determining possible analytes to be used as biomarkers. Furthermore, this article will emphasize why standardization of analytical techniques and establishment of referent cytokine and MMP levels are necessary if these analytes are to be used as biomarkers for the diagnosis, prognosis and evaluation of treatment in the context of HF.

Impact of exercise training on myostatin expression in the myocardium and skeletal muscle in a chronic heart failure model

AIMS

In late-stage chronic heart failure (CHF), elevated cytokines and cachexia are often observed. Several studies have shown that exercise training exerts beneficial effects on skeletal muscle in this setting. Furthermore, it has been shown that the expression of myostatin, a key regulator of skeletal muscle mass, is increased in a variety of cachectic states. This study aimed to investigate the expression of myostatin in CHF, the influence of exercise training on myostatin levels, and regulation of myostatin by tumour necrosis factor-alpha (TNF-alpha).

METHODS AND RESULTS

In an animal model of CHF (LAD-ligation model), protein expression of myostatin was elevated 2.4-fold in the skeletal muscle and more than four-times in the myocardium, compared with control (Co). Exercise training on a treadmill over 4 weeks led to a significant reduction in myostatin protein expression in the skeletal muscle and the myocardium of CHF animals, with values returning to baseline levels. In differentiated C2C12 cells, TNF-alpha induced the expression of myostatin through a p38MAPK-dependent pathway involving nuclear factor kappa-B (NF-kappaB). The increased TNF-alpha mRNA levels in the skeletal muscle of CHF animals correlated significantly with myostatin expression.

CONCLUSION

These alterations in myostatin expression in the skeletal and heart muscle following exercise training could help to explain the beneficial anti-catabolic effects of exercise training in CHF.

Cytokines and acute heart failure

In patients with chronic heart failure, ongoing myocardial injury partially results from activation of the inflammatory system, with production and release of proinflammatory cytokines, activation of the complement system, production of autoantibodies, overexpression of major histocompatibility complex molecules, and expression of adhesion molecules that may perpetuate the inflammatory state. Acute decompensated heart failure modifies the course of chronic heart failure and worsens outcomes via a combination of potential mechanisms, including neurohormonal activation, apoptosis, and the inflammatory cascade. Proinflammatory cytokines, including tumor necrosis factor-alpha and interleukin-6, play a pathogenetic role in chronic heart failure, and anti-inflammatory immune therapy is currently under investigation. In acute decompensation of chronic heart failure, the change in the inflammatory cytokine activation cascade is less clear. Larger investigational studies are needed to assess the exact roles of circulating and intracardiac cytokines in this particular patient population.

Preferential existence of death-inducing proteins in the human cardiomyopathic left ventricle

INTRODUCTION

Idiopathic or acquired dilated cardiomyopathy (DCM) is a leading health threat resulting in considerable mortality and serious long-term disability with a substantial economic healthcare expenditure. The purpose of this study was to investigate the modulation of apoptotic signaling genes in human cardiomyopathy.

METHODS

Cardiac tissue was obtained from six heart transplant recipients (age = 43 +/- 7 y) with DCM. Equivalent control specimens were taken from six healthy heart donors (age = 33 +/- 4 y). The mRNA expression of death-inducing proteins, the death (DRs) and decoy receptors (DcRs), in the four cardiac chambers was quantified using real time polymerase chain reaction LightCycler (Roche Diagnostics GmbH, Mannheim, Germany). Immunodetectable receptor protein expression was quantified densitometrically. Data were analyzed by analysis of variance and unpaired Student's t-test.

RESULTS

In DCM tissues, DR1 mRNA was elevated by 42.7% (P < 0.01) in the left ventricle (LV) and 56.4% (P < 0.001) in the left atrium (LA), while DR2 increased by 112.5% (P < 0.00001) in LV and 45.8% (P < 0.05) in LA. Increase in DR4 was 29.6% (P < 0.01) in LV, 82.5% (P < 0.01) in the right ventricle (RV), 210.8% (P < 0.01) in LA, and 99.1% (P < 0.01) in the right atrium (RA). DR5 was elevated by 66.7% (P < 0.01) in LV, 181.8% (P < 0.005) in LA, and 90.2% (P < 0.05) in RA. DcR1 decreased by 30.8% in LV, 44% (P < 0.05) in LA, and 12.5% in RA; DcR3 by 67.1% (P < 0.0001) in LV, 82.4% (P < 0.0001) in RV, 85.1% (P < 0.0001) in LA, and 84.6% (P < 0.0001) in RA. The trends in mRNA expression were comparable to the changes in protein expression.

CONCLUSIONS

Left heart-sided increase of death-inducing proteins in human cardiomyopathy is suggestive of their potential modulatory roles in death-related signaling in the pathogenesis of end-stage myocardial failure.

Maximum oxygen uptake at peak exercise in elderly patients with coronary artery disease and preserved left ventricular function: the role of inflammation on top of tissue Doppler-derived systolic and diastolic function

BACKGROUND

Several studies have shown that longitudinal systolic function and left ventricular filling pressures, as assessed with tissue Doppler imaging, predict exercise capacity.

AIM

The aim of this study was to evaluate whether natriuretic peptides and inflammatory parameters can independently predict maximum oxygen uptake at peak exercise (VO2max) on top of tissue Doppler imaging-derived markers.

METHODS

We evaluated 142 patients (age 70 +/- 6 years, 77% men) with known or suspected coronary artery disease and a preserved left ventricular ejection fraction (> or = 50%). All patients underwent bicycle spiroergometry, and N-terminal pro-B-type natriuretic peptide levels were determined. Cytokines (IL-6 and soluble tumor necrosis factor receptors 1 and 2) and high-sensitivity C-reactive protein were measured as inflammatory markers. Tissue Doppler imaging was applied to evaluate peak long axis systolic velocities (Sm) and early mitral annulus velocities (E'). Ratio of early transmitral flow (E) to E' was assessed as marker of left ventricular filling. Analysis of variance, comparing VO2max quartiles, was used to determine univariate predictors and linear regression to determine multivariate VO2max predictors.

RESULTS

Average VO2max was 18.5 +/- 5.7 mL/kg per minute (range 6-36.6). Compared with the highest quartile, patients with low VO2max were more frequently women (P < .0001). N-terminal pro-B-type natriuretic peptide and cytokine levels were significantly higher in the lower VO2max categories. Longitudinal myocardial velocities increased, and E/E' decreased along with increasing VO2max. In multivariate linear regression analysis, VO2max was independently predicted by sex, glucose, Sm, E/E', and cytokine levels.

CONCLUSION

Maximum oxygen uptake at peak exercise in patients with known or suspected coronary artery disease and preserved systolic function was independently predicted by inflammatory makers on top of tissue Doppler-derived systolic and diastolic function.

Nutritional Recommendations for Patients With Heart Failure

Promoting optimal nutritional intake may play an important role in the management of patients with heart failure. Unfortunately, no nutritional guidelines are currently available to assist clinicians in assuring adequate nutritional intake of these patients. The purposes of this article are to review currently available information on nutrition in heart failure and outline initial recommendations for micronutrient, protein, and omega-3 fatty intake. In addition, implications regarding the recent data showing improved health outcomes in obese patients are also addressed.

Immune activation is associated with reduced skeletal muscle mass and physical function in chronic heart failure

BACKGROUND

Chronic heart failure is characterized by immune activation and increased circulating levels of cytokines. Whether humoral factors contribute to the peripheral manifestations of the heart failure syndrome, such as muscle atrophy and reduced physical work capacity, however, is not clear.

METHODS

We measured circulating cytokines (tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6)), their soluble receptors (sTNF-alpha RII, IL-6sR), markers of immune activation (C-reactive protein (CRP)), muscle mass, aerobic capacity and muscle strength in 10 patients with heart failure (mean +/- S.E.; 63 +/- 3 years) and 11 controls (70 +/- 3 years).

RESULTS

Heart failure patients exhibited decreased aerobic capacity (P < 0.01) and leg muscle strength (P < 0.05). Reduced muscle strength persisted in heart failure patients after statistical adjustment for differences in skeletal muscle size. All inflammatory markers were increased in heart failure patients (P < or = 0.05 to P < 0.01) compared to controls, with the exception of TNF-alpha. Despite no group differences in TNF-alpha, higher concentrations of this cytokine were correlated to lower skeletal muscle mass in the combined study population (range of r-values: -0.436 to -0.545; P < 0.05 to P < 0.02), as were IL-6 levels (range of r-values: -0.438 to -0.443; P < 0.05). TNF-alpha, sTNF-alpha RII, IL-6 and CRP showed strong negative relationships to aerobic capacity (range of r-values: -0.579 to -0.751; P < 0.01 to P < 0.001). In addition, elevated levels of IL-6 and TNF-alpha were associated with reduced leg and forearm skeletal muscle strength (range of r-values: -0.440 to -0.674; P < 0.05 to P < 0.01). Finally, correlations between cytokines and functional measures were present when heart failure patients were analyzed separately (range of r-values: -0.646 to -0.673; P < 0.05).

CONCLUSIONS

Our results suggest that circulating cytokines are related to both skeletal muscle mass and physical function. These findings provide further evidence to support the hypothesis that immune activation contributes to skeletal muscle atrophy and reduced functional capacity in heart failure patients.

Circulating adiponectin concentrations in patients with congestive heart failure

OBJECTIVES

To determine concentrations of adiponectin and its predictive value on outcome in a cohort of patients with congestive heart failure (CHF).

METHODS

Serum and clinical data were obtained for outpatients with clinically controlled CHF (n = 175). Serum concentrations of adiponectin, C reactive protein, N-terminal pro-brain natriuretic peptide (NT-proBNP), interleukin (IL) -1beta, IL-6, IL-8, IL-10, IL-12, tumour necrosis factor alpha and CD-40 ligand were determined. The association of adiponectin with the clinical severity of CHF was sought as well as the predictive value of this adipokine on mortality, CHF hospitalisations or the occurrence of each of these end points.

RESULTS

Concentrations of adiponectin were significantly increased in patients with CHF. Patients with higher New York Heart Association class had significantly higher serum concentrations of adiponectin. Adiponectin serum concentrations were lower in patients with diabetes and CHF as well as in patients with ischaemic cardiomyopathy. Serum adiponectin concentration was positively associated with age and NT-proBNP but was negatively correlated with C reactive protein concentrations. Serum adiponectin above the 75th centile was found to be an independent predictor of total mortality, CHF hospitalisations or a composite of these end points over a two-year prospective follow up.

CONCLUSION

Adiponectin is increased in CHF patients and predicts mortality and morbidity.

Dietary Fat Intake and Proinflammatory Cytokine Levels in Patients With Heart Failure

BACKGROUND

Dietary fat intake affects proinflammatory cytokine levels of healthy adults. Whether dietary fats have similar effects in patients with heart failure (HF) is unknown. The purposes of this study were to determine (1) effect of dietary fat on interleukin (IL)-6, tumor necrosis factor (TNF)-alpha, and soluble receptors sTNF-R1 and sTNF-R2 levels in patients with HF and (2) subsequent impact of these levels on event-free survival.

METHODS AND RESULTS

Forty-two patients provided 4-day food diaries and blood for cytokines. Event-free survival curves were calculated by Kaplan-Meier method and groups compared using log-rank test. IL-6 was not related to fat intake. TNF-alpha levels were elevated in patients with diets higher versus lower in saturated (6.9 +/- 5 versus 4.2 +/- 2 pg/mL) and trans fats (6.8 +/- 4.5 versus 4.5 +/- 2.8 pg/mL). Patients consuming diets higher in polyunsaturated fats had lower sTNF-R1 (2391 +/- 1010 versus 3373 +/- 2098 pg/mL) and sTNF-R2 (3803 +/- 1187 versus 5974 +/- 3275 pg/mL) levels. Higher omega-3 intake produced similar results: sTNF-R1 (2323 +/- 1304 versus 3307 +/- 1973) and sTNF-R2 (4117 +/- 2646 versus 5409 +/- 2801). Event-free survival was decreased in patients with higher TNF-alpha and sTNF-R1 levels.

CONCLUSION

Dietary fat intake may affect proinflammatory cytokine levels in patients with HF. Research to determine whether changing composition of dietary fat can alter proinflammatory cytokine activity of HF patients is warranted.

Time-course of changes in the levels of interleukin 6 in acutely decompensated heart failure

BACKGROUND

Although cytokine elevation has been demonstrated in chronic heart failure, little attention has been focused on cytokine levels during the acute stage. We examined the changes of cytokine levels in patients with acutely decompensated heart failure to investigate their relationship with severity of heart failure.

METHODS

Patients with acutely decompensated heart failure (73 patients; 72+/-2 years) were included. Blood samples were taken from the peripheral vein on admission before the start of drug therapy, at 12, 24, 48 and 72 h as well as 1, 2 and 4 weeks after admission. Control data were obtained from age-matched normal patients who had no cardiovascular disease. Serum IL-6, IL-1beta and TNF-alpha levels were measured using the ELISA method.

RESULTS

Mean IL-6, IL-1beta and TNF-alpha levels on admission were significantly higher than those in the control patients (p<0.001). IL-6 peaked at 12 h and declined thereafter, whereas IL-1beta and TNF-alpha remained unchanged throughout the duration of the study. Peak IL-6 significantly correlated with pulmonary wedge pressure on admission (r=0.332, p=0.0041). % change of IL-6 levels between peak (12 h after admission) and 24 h was significantly correlated with that of pulmonary wedge pressure between peak (on admission) and 24 h (r=0.308, p=0.0081). Peak IL-6 in patients treated with mechanical ventilation on admission was significantly higher than that in patients who underwent no mechanical ventilation (p<0.05).

CONCLUSIONS

IL-6 levels possibly reflect the severity of heart failure and thus may be useful for the evaluation of disease status in acutely decompensated heart failure.

Effects of long-term captopril andl-arginine treatment on ventilation and blood pressure in obese male SHHF rats

We investigated the effects of captopril (Cap) and l-arginine (Arg) on hypertension and cardiopulmonary function. Our hypothesis was that Cap therapy or Arg will improve cardiopulmonary risk factors for hypertension and hypoventilation in the obese spontaneously hypertensive heart failure rat, which is characterized by hypertension, obesity, and disorders of lipid and carbohydrate metabolism. For the first study, one group of rats received Cap in drinking water, and a second group received deionized water (DI). For the second study, rats were further subdivided. Some Cap-treated rats continued on this treatment, and the other half were now given DI to determine whether there would be residual effects of Cap treatment. A subgroup of rats who had received DI was then given Arg, whereas the rest remained on DI. In the first study, Cap-treated rats exhibited decreases in systolic and diastolic blood pressures, frequency of breathing, and minute ventilation, but ventilatory control was maintained. In contrast, blood pressures and relative ventilation to metabolism were higher in the DI-treated group. Removal of Cap increased blood pressure and decreased tidal volume while these rats maintained frequency. Although Arg-treated rats did not exhibit a decrease of blood pressure, ventilation was maintained in this group by preserving tidal volume. Thus Cap and Arg affected ventilation through different mechanisms independent of blood pressure.

Nutritional strategy in the management of heart failure in adults

The incidence of congestive heart failure (CHF) is increasing in Westernized countries, and patients with CHF experience poor quality of life (functional impairment, high hospitalization rate and high mortality). Malnutrition occurring during the course of CHF is referred to as cardiac cachexia and is associated with higher mortality independent of the severity of CHF. Cardiac cachexia involving a loss of more than 10% of lean body mass can clinically be defined as a bodyweight loss of 7.5% of previous dry bodyweight in a period longer than 6 months. The energy requirements of patients with CHF, whether cachectic or not, are not noticeably modified since the increase in resting energy expenditure is compensated by a decrease in physical activity energy expenditure. Malnutrition in CHF has been ascribed to neurohormonal alterations, i.e. anabolic/catabolic imbalance and increased cytokine release. Anorexia may occur, particularly during acute decompensation of CHF. Function is impaired in CHF, because of exertional dyspnea and changes in skeletal muscle. Decreased exercise endurance seems to be related to decreased mitochondrial oxidative capacities and atrophy of type 1 fibers, which are attributed to alteration in muscle perfusion and are partially reversible by training. Malnutrition could also impair muscle function, because of decreased muscle mass and strength associated with decreased glycolytic capacities and atrophy of type 2a and 2b fibres. With respect to the putative mechanisms of cardiac cachexia, anabolic therapy (hormones or nutrients) and anticytokine therapy have been proposed, but trials are scarce and often inconclusive. In surgical patients with CHF, perioperative (pre- and postoperative) nutritional support has been shown to be effective in reducing the mortality rate. Long term nutritional supplementation trials in patients with CHF and cachexia are thus required to establish recommendations for the nutritional management of patients with CHF.

Increased toll-like receptor 4 in the myocardium of patients requiring left ventricular assist devices

BACKGROUND

Cytokine activation in the myocardium of deteriorating patients with heart failure who undergo left ventricular assist-device (LVAD) implantation has been documented, but the underlying mechanisms remain poorly understood. We hypothesized the innate immune system is activated with expression of Toll-like receptor 4 (TLR4), leading to cytokine activation in these patients.

METHODS

We used quantitative real-time reverse-transcriptase polymerase chain reaction to measure TLR4, interleukin-1 (IL-1) receptor, IL-1 beta, IL-6, and tumor necrosis factor alpha (TNF-alpha) mRNA expression in myocardial samples from 36 patients. We compared 18 patients who underwent LVAD implantation with 18 patients with less severe heart failure who underwent elective heart transplantation.

RESULTS

Toll-like receptor 4 expression was 1.69-fold greater (p < 0.05) and IL-1 receptor expression was 3.64-fold greater (p < 0.0001) in the deteriorating patients who required LVADs. Myocardial TNF-alpha (1.71-fold, p < 0.05), IL-6 (2.57-fold, p < 0.005), and IL-1 beta (9.78-fold, p < 0.001) also were increased in the LVAD candidates. Toll-like receptor 4 expression correlated strongly with IL-1 receptor expression (r= 0.75, p < 0.0001) and with IL-1 beta expression in individual patients (r = 0.7, p < 0.0001). Interleukin-1 receptor expression also correlated with IL-1 beta expression (r = 0.78, p < 0.0001) within patients. We found no correlation between TLR4 and either TNF-alpha or IL-6 expression.

CONCLUSIONS

Patients who required LVAD support showed evidence of innate immune system activation, indicated by an increase in the key effector molecule TLR4 associated with a specific pattern of cytokine expression in the myocardium.

Interleukin-6 and Cardiovascular Diseases

Inflammatory cytokines are important for both cardiovascular scientists and practicing clinicians. Interleukin-6 (IL-6) has been emphasized by reports of elevated circulating as well as intracardiac IL-6 levels in patients with congestive heart failure (CHF). IL-6 may contribute to the progression of myocardial damage and dysfunction in chronic heart failure syndrome resulting from different causes. As the cause of CHF in cardiomyopathy, myocarditis, allograft rejection, and left ventricular assist device (LVADs) conditions, circulating IL-6 levels are associated with the severity of left ventricular dysfunction, and are also strong predictors of subsequent clinical outcomes. Continuous and excessive production of IL-6 promotes myocardial injury by breaking down both cytokine networks and viral clearance under viral myocarditis. Although IL-6 is likely important in the process of viral antigen presentation, early activation of immune responses and attenuation of viral replication also appear to be significant in an animal model of viral myocarditis. IL-6 can cause cardiac hypertrophy through the IL-6 signal transducing receptor component, glycoprotein 130. There are several interesting cases of cardiac myxoma complicated with mediastinal lymphadenopathy or left ventricular hypertrophy. Increased expression of IL-6 is observed in the myocardium of all donor hearts showing marked dysfunction. Myocardial IL-6 concentrations are also significantly higher in LVAD candidates compared with advanced heart failure patients. Although the IL-6 family plays a central role in the pathophysiology of cardiovascular diseases, it remains to be determined whether the IL-6 family is beneficial or detrimental. Future study will be needed to resolve this question.

Prognostic value of interleukin-6, plasma viscosity, fibrinogen, von Willebrand factor, tissue factor and vascular endothelial growth factor levels in congestive heart failure

BACKGROUND

Congestive heart failure (CHF) carries a poor prognosis with a high mortality rate, frequent hospitalizations and increased risk of thrombotic complications such as stroke. Cytokines may contribute to the progression and prothrombotic state of CHF, including the pro-inflammatory interleukin-6 (IL-6) and the pro-angiogenic vascular endothelial growth factor (VEGF), both of which are raised in CHF. The procoagulant properties of both cytokines may be mediated via tissue factor (TF), a potent clotting activator. We hypothesized that plasma levels of these markers, as well as levels of plasma viscosity, fibrinogen, soluble P-selectin and von Willebrand factor (markers of abnormal rheology, clotting, platelet activation, and endothelial damage, respectively) will be useful in predicting morbidity and mortality in chronic stable CHF.

METHODS AND RESULTS

One hundred and twenty consecutive out-patients with chronic stable CHF (92 males; mean [SD] age 64 [11] years, mean [SD] left ventricular ejection fraction of 29 [6]%) were recruited and followed for 2 years during which 42 patients reached a clinical end-point of all-cause mortality and cardiovascular hospitalizations, including stroke and myocardial infarction. Plasma IL-6 (P=0.003) and TF (P=0.013) levels, but not other research indices, were higher in those who suffered events compared with those without events. Predictors of end-points were high (> or =median) TF (P=0.011), and IL-6 (P=0.023) levels, as well as the lowest quartile of a left ventricular ejection fraction (P=0.007). A strong correlation was present between TF and IL-6 levels (r=0.59; P<0.0001) and with VEGF levels (r=0.43; P<0.0001).

CONCLUSION

IL-6 and TF are predictors of poor prognosis in chronic CHF, raising the hypothesis that IL-6 may contribute to the progression and thrombotic complications of CHF via its actions on TF expression. Although VEGF did not independently predict outcome in chronic CHF, the possibility arises that it may act with IL-6 to induce TF expression.

Anti-inflammatory effects of exercise training in the skeletal muscle of patients with chronic heart failure

OBJECTIVES

The aim of this study was to assess the effects of regular physical exercise on local inflammatory parameters in the skeletal muscle of patients with chronic heart failure (CHF).

BACKGROUND

Inflammatory activation with increased serum cytokine levels and expression of inducible nitric oxide synthase (iNOS) in the myocardium and peripheral skeletal muscles has been described in CHF.

METHODS

Twenty male patients with stable CHF (left ventricular ejection fraction 25 +/- 2%; age 54 +/- 2 years) were randomized to a training group (n = 10) or a control group (n = 10). At baseline and after six months, serum samples and vastus lateralis muscle biopsies were obtained. Serum tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and IL-1-beta levels were measured by enzyme-linked immunosorbent assay, local cytokine, and iNOS expression by real-time polymerase chain reaction.

RESULTS

Exercise training improved peak oxygen uptake by 29% in the training group (from 20.3 +/- 1.0 to 26.1 +/- 1.5 ml/kg. min; p < 0.001 vs. control group). While serum levels of TNF-alpha, IL-6, and IL-1-beta remained unaffected by training, local skeletal muscle TNF-alpha decreased from 1.9 +/- 0.4 to 1.2 +/- 0.3 relative U (p < 0.05 for change vs. control group), IL-6 from 71.3 +/- 16.5 to 41.3 +/- 8.8 relative U (p < 0.05 vs. begin), and IL-1-beta from 2.7 +/- 1.1 to 1.4 +/- 0.6 relative U (p = 0.02 vs. control group). Exercise training also reduced local iNOS expression by 52% (from 6.3 +/- 1.2 to 3.0 +/- 1.0 relative U; p = 0.007 vs. control group).

CONCLUSIONS

Exercise training significantly reduced the local expression of TNF-alpha, IL-1-beta, IL-6, and iNOS in the skeletal muscle of CHF patients. These local anti-inflammatory effects of exercise may attenuate the catabolic wasting process associated with the progression of CHF.

Interleukin-6, tissue factor and von Willebrand factor in acute decompensated heart failure: relationship to treatment and prognosis

Arterial thrombotic and thromboembolic complications are increased in congestive heart failure (CHF), and are a particular problem in acute decompensated heart failure, which carries a poor prognosis. As interleukin-6 (IL-6) has been shown to induce the potent procoagulant tissue factor (TF) in experimental models, we hypothesized that the pro-inflammatory IL-6 may be one mechanism contributing to thrombosis in heart failure, mediated via endothelial expression of TF on activated/damaged cells [indicated by plasma von Willebrand factor (vWF)]. Seventy-seven patients (67% men, New York Heart Association class III-IV, 87%) with acute CHF were recruited, and were compared with 53 chronic stable CHF patients in sinus rhythm (66% men, New York Heart Association class III-IV, 2%) and 37 healthy controls (68% men). Acute CHF patients in sinus rhythm had elevated baseline levels of IL-6 (P < 0.0001), TF (P = 0.041) and vWF (P < 0.0001) (all measured by enzyme-linked immunosorbent assay) compared with both chronic CHF and healthy control groups. A correlation exists in acute CHF between baseline TF and IL-6 (Spearman r = 0.64, P < 0.0001). After 3 months treatment, with control or alleviation of heart failure symptoms in 40 patients, there was a fall in levels of IL-6 (P < 0.0001) and vWF (P < 0.0001), but levels still remained significantly higher than healthy controls. Patients who died at 6 months follow-up also had higher baseline levels of IL-6 (P = 0.008), TF (P = 0.037) and vWF (P = 0.039) when compared with those who remained alive. Elevated IL-6 may contribute to the thrombotic and thromboembolic complications in acute heart failure, in a process mediated via increased TF and vWF. Improvement of symptoms and plasma markers after treatment of acute CHF and prediction of prognosis by the markers may be useful in the clinical setting.

Elevated plasma amylase levels in advanced chronic heart failure secondary to ischemic or idiopathic dilated cardiomyopathy: correlation with circulating interleukin-6 activity

It has been reported that proinflammatory cytokine activation is associated with both mesenteric venous congestion and peripheral tissue underperfusion in advanced chronic heart failure. The aim of our study was to investigate if plasma amylase (as an easily approached marker of a low-grade peripheral organ injury caused by elevated systemic venous pressure and reduced cardiac output) is elevated in severe heart failure and if this elevation is correlated with cytokine and neurohormonal activation in the plasma of heart failure patients. Plasma levels of amylase, tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), granulocyte-macrophage colony-stimulating factor (GM-CSF), norepinephrine, and renin activity were measured in 43 severe heart failure patients (ischemic, 28; dilated, 15; left ventricular ejection fraction [LVEF] 27 +/- 3%; New York Heart Association [NYHA] classes III-IV), in 37 mild heart failure patients (ischemic, 26; dilated, 11; LVEF, 33 +/- 5%; NYHA classes I-II), and in 20 age-matched and gender-matched healthy controls. NYHA III-IV heart failure patients exhibited significantly higher plasma levels of amylase (342 +/- 19 vs. 174 +/- 13 U/L, p < 0.01), TNF-alpha (6.2 +/- 0.5 vs. 4.2 +/- 0.3 pg/ml, p < 0.01), IL-6 (5.9 +/- 0.3 vs. 4.4 +/- 0.3 pg/ml, p < 0.05), GM-CSF (21.2 +/- 2.7 vs. 4.1 +/- 0.9 pg/ml, p < 0.001), and neurohormones (both p < 0.001) compared with NYHA I-II heart failure patients and healthy controls (amylase, 165 +/- 11 U/L, p < 0.01; TNF-alpha, 2.7 +/- 0.3 pg/ml, p < 0.001; IL-6, 3.2 +/- 0.2 pg/ml, p < 0.01; GM-CSF, 3.1 +/- 0.7 pg/ml, p < 0.001). Only in NYHA III-IV heart failure patients, plasma amylase levels were significantly correlated with plasma IL-6 activity (r = 0.86, p < 0.001), plasma norepinephrine levels (r = 0.82, p < 0.001) and right atrial pressure (r = 0.52, p < 0.05). Additionally, circulating IL-6 was also significantly correlated with plasma norepinephrine (r = 0.86, p < 0.001) and right atrial pressure (r = 0.57, p < 0.01). In conclusion, plasma amylase levels were elevated in severe heart failure patients and correlated well with circulating IL-6 activation, possibly as a result of both mesenteric venous congestion and impaired peripheral tissue perfusion observed in advanced chronic heart failure. However, the lack of association between plasma IL-6 and amylase levels in mild heart failure patients indicates an independent correlation of each variable with the functional status of the disease.

Heart failure as an inflammatory condition: potential role for androgens as immune modulators

Heart failure has traditionally been considered a disease of the myocardium, with symptoms arising from altered haemodynamics. However, it is now recognised that, in addition to marked neuroendocrine disturbance, there is perturbation of cytokine expression in patients with heart failure, resulting in an inflammatory imbalance. This not only influences symptoms, but also plays a central role in the underlying pathophysiological processes of heart failure, leading to disease progression and poorer prognosis. Recognition of the influence of cytokines, in particular tumour necrosis factor, has opened a new avenue for potential therapies for heart failure. Current approaches involve immunomodulation, aimed at suppressing tumour necrosis factor. We suggest that androgens may potentially offer a superior therapeutic strategy by their well-recognised non-specific immunosuppressive and anti-inflammatory effects. Studies of cell lines, human mononuclear cells and animals in vivo have demonstrated the 'anti-cytokine' actions of androgens, and we have found a similar action in whole blood from patients with heart failure. These effects, along with the anabolic action of these agents, make androgens an attractive potential option for treatment of patients with heart failure.

Gender modulates activation of renin-angiotensin and endothelin systems in hypertension and heart failure

Sexual dimorphism may occur during the development of hypertension and congestive heart failure (CHF). Male and female spontaneous hypertension heart failure (SHHF) rats with established hypertension, but before CHF (age 5-8 mo) and during cardiac decompensation leading to CHF (age 18-20 mo in male rats and 22-24 mo in female rats), were studied. At 5-8 mo, male SHHF rats showed early activation of the renin-angiotensin system (RAS), as indicated by increased plasma renin activity (PRA) and higher serum angiotensin-converting enzyme activity compared with female rats. The increase in PRA in female rats was delayed compared with males rats, but it reached comparable levels just before CHF. Urinary endothelin excretion was significantly greater in 5- to 8-mo-old female rats compared with age-matched male rats. Urinary endothelin excretion increased in both male and female rats as CHF developed. Plasma atrial natriuretic peptide (ANP) was comparable at both time points, and both genders showed similar, marked increases as CHF developed. In conclusion, male rats show early activation of the RAS, whereas female rats show early activation of the endothelin vasopressor system. During cardiac decompensation, generalized activation of the RAS, endothelin, and ANP systems occurs and is similar in male and female SHHF rats.

The effects of aprotinin and steroids on generation of cytokines during coronary artery surgery

OBJECTIVE

To compare the efficacy of aprotinin and methylprednisolone in reducing cardiopulmonary bypass (CPB)-induced cytokine release, to evaluate the effect of myocardial cytokine release on systemic cytokine levels, and to determine the influence of cytokine release on perioperative and postoperative hemodynamics.

DESIGN

Prospective, randomized clinical trial.

SETTING

University teaching hospital and clinics.

PARTICIPANTS

Thirty patients undergoing elective coronary artery bypass graft surgery.

INTERVENTION

Patients were randomly allocated into groups treated with aprotinin (n = 10) or methylprednisolone (n = 10) or into an untreated control group (n = 10). Aprotinin-treated patients received aprotinin as a high-dose regimen (6 x 10(6) KIU), and methylprednisolone-treated patients received methylprednisolone (30 mg/kg intravenously) before CPB.

MEASUREMENTS AND MAIN RESULTS

Patients were analyzed for hemodynamic changes and alveolar-arterial PO2 difference (AaDO2) until the first postoperative day. Plasma levels of proinflammatory cytokines (tumor necrosis factor [TNF]-alpha, interleukin [IL]-1beta, IL-6, and IL-8) were measured in peripheral arterial blood immediately before the induction of anesthesia, 5 minutes before CPB, 3 minutes after the start of CPB, 2 minutes after the release of the aortic cross-clamp, 1 hour after CPB, 6 hours after CPB, and 24 hours after CPB; and in coronary sinus blood immediately before CPB and 2 minutes after the release of the aortic cross-clamp. The hemodynamic parameters did not differ among the groups throughout the study. After CPB, AaDO2 significantly increased (p < 0.05) in all groups. A significant decrease in AaDO2 was observed in aprotinin-treated patients at 24 hours after CPB compared with the other groups (p < 0.05). TNF-alpha level from peripheral arterial blood significantly increased in control patients 1 hour after CPB (p < 0.01) and did not significantly increase in methylprednisolone-treated patients throughout the study. In all groups, IL-6 levels increased after the release of the aortic cross-clamp and reached peak values 6 hours after CPB. At 6 hours after CPB, the increase in IL-6 levels in methylprednisolone-treated patients was significantly less compared with levels measured in control patients and aprotinin-treated patients (p < 0.001). In control patients, IL-8 levels significantly increased 2 minutes after the release of the aortic cross-clamp (p < 0.05), and peak values were observed 1 hour after CPB (p < 0.01). IL-8 levels in control patients were significantly higher compared with patients treated with aprotinin and patients treated with methylprednisolone 1 hour after CPB (p < 0.05).

CONCLUSION

This study showed that methylprednisolone suppresses TNF-alpha, IL-6, and IL-8 release; however, aprotinin attenuates IL-8 release alone. Methylprednisolone does not produce any additional positive hemodynamic and pulmonary effects. An improved postoperative AaDO2 was observed with the use of aprotinin.

Circulating interleukin-6 significantly correlates to thyroid hormone in acute myocardial infarction but not in chronic heart failure

To investigate relationships between thyroid states and the cardiac endocrine system, we analyzed thyrotropin (TSH), thyroid hormone, plasma levels of interleukin-6 (IL-6) and brain natriuretic peptide (BNP) in 50 patients with chronic heart failure (CHF), in 30 patients with heart failure from acute myocardial infarction (AMI), and in 15 controls. Plasma levels of IL-6 and BNP in both CHF and AMI were significantly elevated, while free triiodothyronine (FT3) was significantly decreased compared to controls. FT3/free thyroxine (FT4) ratio was significantly decreased in CHF but not in AMI compared to controls. In CHF, diuretic treatment diminished circulating BNP but not IL-6, while diuretic treatment increased FT3/FT4 ratio. In AMI, FT3/FT4 ratio was significantly decreased 72 h compared to 12 h after the onset of AMI, while BNP and IL-6 were significantly increased 72 h compared to 12 h after the onset of AMI. In both CHF and AMI, BNP significantly correlated with FT4. On the other hand, significant correlations between IL-6 and FT3, and between IL-6 and FT3/FT4 ratio were detected in AMI but not in CHF. This preliminary study suggests that IL-6, BNP and thyroid hormone reflect ventricular dysfunction in both acute and chronic heart failure, and that IL-6 significantly relates to circulating thyroid hormone in AMI but not in CHF.

Tumor necrosis factor-alpha is expressed in donor heart and predicts right ventricular failure after human heart transplantation

BACKGROUND-Myocardial failure is an important problem after heart transplantation. Right ventricular (RV) failure is most common, although its mechanisms remain poorly understood. Inflammatory cytokines play an important role in heart failure. We studied the expression of tumor necrosis factor (TNF)-alpha and other cytokines in donor myocardium and their relationship to the subsequent development of RV failure early after transplantation. METHODS AND RESULTS-Clinical details were obtained, and ventricular function was assessed by transesophageal echocardiography in 26 donors before heart retrieval. A donor RV biopsy was obtained immediately before transplantation, and each recipient was followed for the development of RV failure. Reverse transcriptase-polymerase chain reaction was performed to detect TNF-alpha, interleukin-2, interferon-gamma, and inducible nitric oxide synthase expression. Eight of 26 recipients (30.8%) developed RV failure. Seven of these 8 (87.5%) expressed TNF-alpha, but only 4 of the 18 (22.2%) who did not develop RV failure expressed TNF-alpha (P<0.005). As a predictor of RV failure, TNF-alpha mRNA had a sensitivity of 87.5%, a specificity of 83.3%, a positive predictive value of 70%, and a negative predictive value of 93.7%. Western blotting demonstrated more TNF-alpha protein in the myocardium of donor hearts that developed RV failure (658+/-60 versus 470+/-57 optical density units, P<0.05). Immunocytochemistry localized TNF-alpha expression to cardiac myocytes. Reverse transcriptase-polymerase chain reaction detected interferon-gamma in 2 (7.7%), interleukin-2 in 1 (3.8%), and inducible nitric oxide synthase mRNA in 1 (3.8%) of the 26 donor hearts, none of which developed RV failure. CONCLUSIONS-TNF-alpha expression in donor heart cardiac myocytes seems to predict the development of RV failure in patients early after heart transplantation.

Prognostic value of serum cytokines in patients with congestive heart failure

BACKGROUND

Increased levels of circulating cytokines have been previously reported in patients with congestive heart failure; however, whether they have prognostic implications is still unknown. The aim of this study was to assess the prognostic implications of elevated serum cytokines in patients with heart failure and to identify the predictors of cytokine activation.

METHODS AND RESULTS

We assessed neurohormonal determinations, circulating cytokines, ejection fraction (EF) and end-diastolic and end-systolic left ventricular lengths in 87 patients (aged 57 +/- 9 years) with left ventricular dysfunction (EF 24% +/- 6%). In 48 patients, we also assessed cytokine receptors. During follow-up (mean, 14 +/- 9 months), 8 patients died and 12 had new heart failure episodes that required hospital admission, 5 of whom underwent heart transplantation. The univariate predictors of these events were serum interleukin-6 (IL-6) (p = 0.00001), New York Heart Association (NYHA) functional class (p = 0.0004), tumor necrosis factor-soluble receptor I (p = 0. 001), atrial natriuretic peptide (p = 0.002), tumor necrosis factor-soluble receptor II (p = 0.004), angiotensin II (p = 0.006), serum interleukin-1 beta (p = 0.01), and plasma renin activity (p = 0.02). Increased serum interleukin-6 (>10 pg/ml) was a significant predictor of death or new heart failure episodes according to the Kaplan-Meier survival method by log-rank test (p = 0.004). By Cox regression analysis, serum IL-6 (p = 0.0005) and the NYHA functional class (p = 0.005) were identified as independent predictors of prognosis.

CONCLUSIONS

In patients with congestive heart failure, increased serum IL-6 was identified as a powerful independent predictor of the combined end point: death, new heart failure episodes, and need for heart transplantation.

Predictors of congestive heart failure in the elderly: the Cardiovascular Health Study

OBJECTIVES

We sought to characterize the predictors of incident congestive heart failure (CHF), as determined by central adjudication, in a community-based elderly population.

BACKGROUND

The elderly constitute a growing proportion of patients admitted to the hospital with CHF, and CHF is a leading source of morbidity and mortality in this group. Elderly patients differ from younger individuals diagnosed with CHF in terms of biologic characteristics.

METHODS

We analyzed data from the Cardiovascular Health Study, a prospective population-based study of 5,888 elderly people >65 years old (average 73 +/- 5, range 65 to 100) at four locations. Multiple laboratory measures of cardiovascular structure and function, blood chemistries and functional assessments were obtained.

RESULTS

During an average follow-up of 5.5 years (median 6.3), 597 participants developed incident CHF (rate 19.3/1,000 person-years). The incidence of CHF increased progressively across age groups and was greater in men than in women. On multivariate analysis, other independent predictors included prevalent coronary heart disease, stroke or transient ischemic attack at baseline, diabetes, systolic blood pressure (BP), forced expiratory volume 1 s, creatinine >1.4 mg/dl, C-reactive protein, ankle-arm index <0.9, atrial fibrillation, electrocardiographic (ECG) left ventricular (LV) mass, ECG ST-T segment abnormality, internal carotid artery wall thickness and decreased LV systolic function. Population-attributable risk, determined from predictors of risk and prevalence, was relatively high for prevalent coronary heart disease (13.1%), systolic BP > or =140 mm Hg (12.8%) and a high level of C-reactive protein (9.7%), but was low for subnormal LV function (4.1%) and atrial fibrillation (2.2%).

CONCLUSIONS

The incidence of CHF is high in the elderly and is related mainly to age, gender, clinical and subclinical coronary heart disease, systolic BP and inflammation. Despite the high relative risk of subnormal systolic LV function and atrial fibrillation, the actual population risk of these for CHF is small because of their relatively low prevalence in community-dwelling elderly people.

In vitro and in vivo effects of kinin B(1) and B(2) receptor agonists and antagonists in inbred control and cardiomyopathic hamsters

The aims of this study were to examine the possible alterations occurring in the effects of kinins on isolated aortae of inbred control (CHF 148) and cardiomyopathic (CHF 146) hamsters of 150 - 175 and 350 - 375 days of age. Bradykinin (BK) and desArg(9)BK contracted isolated aortae (with or without endothelium) of hamsters of both strains and ages. After tissue equilibration (90 min), responses elicited by both kinin agonists were stable over the time of experiments. The patterns of isometric contractions of BK and desArg(9)BK were however found to be different; desArg(9)BK had a slower onset and a longer duration of action than BK. Potencies (pEC(50) values) of BK in all groups of hamsters were significantly increased by preincubating the tissues with captopril (10(-5) M). No differences in the pEC(50) values and the E(max) values for BK or desArg(9)BK were seen between isolated vessels from inbred control and cardiomyopathic hamsters. The myotropic effect of BK was inhibited by the selective non peptide antagonist, FR 173657 (pIC(50) 7.25+/-0.12 at the bradykinin B(2) receptor subtype (B(2) receptor)). Those of desArg(9)BK, at the bradykinin B(1) receptor subtype (B(1) receptor) were abolished by either R 715 (pIC(50) of 7. 55+/-0.05; alpha(E) = 0), Lys[Leu(8)]desArg(9)BK (pIC(50) of 7.21+/-0. 01; alpha(E) = 0.22) or [Leu(8)]desArg(9)BK (pIC(50) of 7.25+/-0.02; alpha(E) = 0.18). FR 173657 had no agonistic activity, exerted a non competitive type of antagonism and was poorly reversible (lasting more than 5 h) from B(2) receptor. In vivo, FR 173657 (given per os at 1 and 5 mg kg(-1), 1 h before the experiment) antagonized the acute hypotensive effect of BK in anaesthetized hamsters. It is concluded that aging and/or the presence of a congenital cardiovascular disorder in hamsters are not associated with changes in the in vitro aortic responses to either BK or desArg(9)BK.

Plasma viscosity and fibrinogen in relation to haemodynamic findings in chronic congestive heart failure

The aim of this study was to investigate an inflammatory response indicated by fibrinogen and plasma viscosity in relation to haemodynamic and clinical findings of patients with stable CHF due to coronary heart disease (CHD).

Molecular mechanisms of myocardial remodeling

"Remodeling" implies changes that result in rearrangement of normally existing structures. This review focuses only on permanent modifications in relation to clinical dysfunction in cardiac remodeling (CR) secondary to myocardial infarction (MI) and/or arterial hypertension and includes a special section on the senescent heart, since CR is mainly a disease of the elderly. From a biological point of view, CR is determined by 1 ) the general process of adaptation which allows both the myocyte and the collagen network to adapt to new working conditions; 2) ventricular fibrosis, i.e., increased collagen concentration, which is multifactorial and caused by senescence, ischemia, various hormones, and/or inflammatory processes; 3) cell death, a parameter linked to fibrosis, which is usually due to necrosis and apoptosis and occurs in nearly all models of CR. The process of adaptation is associated with various changes in genetic expression, including a general activation that causes hypertrophy, isogenic shifts which result in the appearance of a slow isomyosin, and a new Na+-K+-ATPase with a low affinity for sodium, reactivation of genes encoding for atrial natriuretic factor and the renin-angiotensin system, and a diminished concentration of sarcoplasmic reticulum Ca2+-ATPase, beta-adrenergic receptors, and the potassium channel responsible for transient outward current. From a clinical point of view, fibrosis is for the moment a major marker for cardiac failure and a crucial determinant of myocardial heterogeneity, increasing diastolic stiffness, and the propensity for reentry arrhythmias. In addition, systolic dysfunction is facilitated by slowing of the calcium transient and the downregulation of the entire adrenergic system. Modifications of intracellular calcium movements are the main determinants of the triggered activity and automaticity that cause arrhythmias and alterations in relaxation.