Plasma endothelin-1-related peptides as the prognostic biomarkers for heart failure: A PRISMA-compliant meta-analysis

sST2 and Big ET-1 as Alternatives of Multi-Biomarkers Strategies for Prognosis Evaluation in Patients Hospitalized with Heart Failure

Objective

To identify biomarkers with independent prognostic value and investigate the prognostic value of multiple biomarkers in combination in patients hospitalized with heart failure.

Methods

A total of 884 consecutive patients hospitalized with heart failure from 2015 to 2017 were enrolled. Twelve biomarkers were measured on admission, and the relationships between biomarkers and outcomes were assessed.

Results

During the median follow-up of 913 days, 291 patients (32.9%) suffered from primary endpoint events. Soluble suppression of tumorigenicity-2 (sST2) (per log [unit] increase, adjusted HR [95% CI]: 1.39 [1.13,1.72], P = 0.002) and big endothelin-1 (big ET-1) (per log [unit] increase, adjusted HR [95% CI]: 1.56 [1.23,1.97], P < 0.001) remained independent predictors of primary endpoint event after adjusting for other predictors including N-terminal pro-B-type natriuretic peptide (NT-proBNP) and high-sensitivity cardiac troponin T (hs-cTnT). Both sST2 (C-statistic: 0.810 vs 0.801, P = 0.005, and 0.832 vs 0.826, P = 0.024, respectively) and big ET-1 (C-statistic: 0.829 vs 0.801, P = 0.001, and 0.843 vs 0.826, P < 0.001, respectively) significantly improved the predictive value for primary endpoint event at 1 year and 3 years. However, only big ET-1 (C-statistic: 0.852 vs 0.846, P = 0.014) significantly improved the predictive value at 3 months when added to clinical predictors and known biomarkers. According to the number of elevated biomarkers (including NT-proBNP, hs-cTnT, sST2, and big ET-1), patients with three or more elevated biomarkers had a higher risk of primary endpoint event compared to those with two elevated biomarkers (P = 0.001), as well as in patients with two elevated biomarkers compared to those with one elevated biomarker (P = 0.004). However, the risk of primary endpoint event was comparable between patients with one elevated biomarker and those with no elevated biomarker (P = 0.582).

Conclusion

Multiple biomarkers in combination could provide a better prognostic value than a single biomarker. sST2 and big ET-1 could act as alternatives of multi-biomarkers strategies for prognosis evaluation beyond NT-proBNP and hs-cTnT in patients hospitalized with heart failure.

Endothelin Receptor Blocker Reverses Breast Cancer-Induced Cardiac Remodeling

Background

Although some cancer therapies have overt and/or subclinical cardiotoxic effects that increase subsequent cardiovascular risk in breast cancer patients, we have recently shown that the breast tumor itself can also induce cardiac hypertrophy through the activation of the endothelin system to contribute to cardiovascular risk. However, the extent to which the suppression of the activation of the endothelin system could improve cardiac remodeling in breast cancer patients has yet to be investigated.

Objectives

We aimed to retrospectively assess the cardiac morphology/function in patients with breast cancer before receiving cancer chemotherapy and to investigate if the suppression of the activation of the endothelin system improves cardiac remodeling in a mouse model of breast cancer.

Methods

Our study involved 28 previously studied women with breast cancer (including 24 after tumor resection) before receiving adjuvant therapy and 17 control healthy women. In addition, we explored how the endothelin system contributed to breast cancer-induced cardiac remodeling using a mouse model of breast cancer.

Results

Our results indicate that before chemotherapy, breast cancer patients already exhibit relative cardiac remodeling and subclinical cardiac dysfunction, which was associated with the activation of the endothelin system. Importantly, our mouse data also show that the endothelin receptor blocker atrasentan significantly lessened cardiac remodeling and improved cardiac function in a preclinical model of breast cancer.

Conclusions

Although our findings should be further examined in other preclinical/clinical models, our data suggest that endothelin receptor blockers may play a role in cardiac health in individuals with breast cancer. (Understanding and Treating Heart Failure With Preserved Ejection Fraction: Novel Mechanisms, Diagnostics and Potential Therapeutics [Alberta HEART]; NCT02052804 and Multidisciplinary Team Intervention in Cardio-Oncology [TITAN]; NCT01621659).

Regression of cardiac hypertrophy in health and disease: mechanisms and therapeutic potential

Left ventricular hypertrophy is a leading risk factor for cardiovascular morbidity and mortality. Although reverse ventricular remodelling was long thought to be irreversible, evidence from the past three decades indicates that this process is possible with many existing heart disease therapies. The regression of pathological hypertrophy is associated with improved cardiac function, quality of life and long-term health outcomes. However, less than 50% of patients respond favourably to most therapies, and the reversibility of remodelling is influenced by many factors, including age, sex, BMI and disease aetiology. Cardiac hypertrophy also occurs in physiological settings, including pregnancy and exercise, although in these cases, hypertrophy is associated with normal or improved ventricular function and is completely reversible postpartum or with cessation of training. Studies over the past decade have identified the molecular features of hypertrophy regression in health and disease settings, which include modulation of protein synthesis, microRNAs, metabolism and protein degradation pathways. In this Review, we summarize the evidence for hypertrophy regression in patients with current first-line pharmacological and surgical interventions. We further discuss the molecular features of reverse remodelling identified in cell and animal models, highlighting remaining knowledge gaps and the essential questions for future investigation towards the goal of designing specific therapies to promote regression of pathological hypertrophy.

Big Endothelin-1 as a Predictor of Reverse Remodeling and Prognosis in Dilated Cardiomyopathy

This study aimed to investigate the predictive value of Big endothelin-1(ET-1) for left ventricular reverse remodeling (LVRR) and prognosis in patients with dilated cardiomyopathy (DCM). Patients with DCM and a left ventricular ejection fraction (LVEF) ≤ 50% from 2008 to 2017 were included. LVRR was defined as the LVEF increased by at least 10% or follow-up LVEF increased to at least 50% with a minimum improvement of 5%; meanwhile, the index of left ventricular end-diastolic diameter (LVEDDi) decreased by at least 10% or LVEDDi decreased to ≤33 mm/m². The composite outcome for prognostic analysis consisted of death and heart transplantations. Of the 375 patients included (median age 47 years, 21.1% female), 135 patients (36%) had LVRR after a median of 14 months of treatment. An independent association was found between Big ET-1 at baseline and LVRR in the multivariate model (OR 0.70, 95% CI 0.55-0.89, p = 0.003, per log increase). Big ET-1, body mass index, systolic blood pressure, diagnosis of type 2 diabetes mellitus (T2DM) and treatment with ACEI/ARB were significant predictors for LVRR after stepwise selection. Adding Big ET-1 to the model improved the discrimination (∆AUC = 0.037, p = 0.042 and reclassification (IDI, 3.29%; p = 0.002; NRI, 35%; p = 0.002) for identifying patients with LVRR. During a median follow-up of 39 (27-68) months, Big ET-1 was also independently associated with the composite outcome of death and heart transplantations (HR 1.45, 95% CI 1.13-1.85, p = 0.003, per log increase). In conclusion, Big ET-1 was an independent predictor for LVRR and had prognostic implications, which might help to improve the risk stratification of patients with DCM.

Endothelium-Derived Relaxing Factors and Endothelial Function: A Systematic Review

BACKGROUND

The endothelium plays a pivotal role in homeostatic mechanisms. It specifically modulates vascular tone by releasing vasodilatory mediators, which act on the vascular smooth muscle. Large amounts of work have been dedicated towards identifying mediators of vasodilation and vasoconstriction alongside the deleterious effects of reactive oxygen species on the endothelium. We conducted a systematic review to study the role of the factors released by the endothelium and the effects on the vessels alongside its role in atherosclerosis.

METHODS

A search was conducted with appropriate search terms. Specific attention was offered to the effects of emerging modulators of endothelial functions focusing the analysis on studies that investigated the role of reactive oxygen species (ROS), perivascular adipose tissue, shear stress, AMP-activated protein kinase, potassium channels, bone morphogenic protein 4, and P2Y2 receptor.

RESULTS

530 citations were reviewed, with 35 studies included in the final systematic review. The endpoints were evaluated in these studies which offered an extensive discussion on emerging modulators of endothelial functions. Specific factors such as reactive oxygen species had deleterious effects, especially in the obese and elderly. Another important finding included the shear stress-induced endothelial nitric oxide (NO), which may delay development of atherosclerosis. Perivascular Adipose Tissue (PVAT) also contributes to reparative measures against atherosclerosis, although this may turn pathological in obese subjects. Some of these factors may be targets for pharmaceutical agents in the near future.

CONCLUSION

The complex role and function of the endothelium is vital for regular homeostasis. Dysregulation may drive atherogenesis; thus, efforts should be placed at considering therapeutic options by targeting some of the factors noted.

Advances in congestive heart failure biomarkers

Congestive heart failure (CHF) is the leading cause of morbidity and mortality in the elderly worldwide. Although many biomarkers associated with in heart failure, these are generally prognostic and identify patients with moderate and severe disease. Unfortunately, the role of biomarkers in decision making for early and advanced heart failure remains largely unexplored. Previous studies suggest the natriuretic peptides have the potential to improve the diagnosis of heart failure, but they still have significant limitations related to cut-off values. Although some promising cardiac biomarkers have emerged, comprehensive data from large cohort studies is lacking. The utility of multiple biomarkers that reflect various pathophysiologic pathways are increasingly being explored in heart failure risk stratification and to diagnose disease conditions promptly and accurately. MicroRNAs serve as mediators and/or regulators of renin-angiotensin-induced cardiac remodeling by directly targeting enzymes, receptors and signaling molecules. The role of miRNA in HF diagnosis is a promising area of research and further exploration may offer both diagnostic and prognostic applications and phenotype-specific targets. In this review, we provide insight into the classification of different biochemical and molecular markers associated with CHF, examine clinical usefulness in CHF and highlight the most clinically relevant.

ET-1 as a Sex-Specific Mechanism Impacting Age-Related Changes in Vascular Function

Aging is a primary risk factor for cardiovascular disease (CVD), which is the leading cause of death in developed countries. Globally, the population of adults over the age of 60 is expected to double by the year 2050. CVD prevalence and mortality rates differ between men and women as they age in part due to sex-specific mechanisms impacting the biological processes of aging. Measures of vascular function offer key insights into cardiovascular health. Changes in vascular function precede changes in CVD prevalence rates in men and women and with aging. A key mechanism underlying these changes in vascular function is the endothelin (ET) system. Studies have demonstrated sex and sex hormone effects on endothelin-1 (ET-1), and its receptors ETA and ETB. However, with aging there is a dysregulation of this system resulting in an imbalance between vasodilation and vasoconstriction. Thus, ET-1 may play a role in the sex differences observed with vascular aging. While most research has been conducted in pre-clinical animal models, we describe more recent translational data in humans showing that the ET system is an important regulator of vascular dysfunction with aging and acts through sex-specific ET receptor mechanisms. In this review, we present translational evidence (cell, tissue, animal, and human) that the ET system is a key mechanism regulating sex-specific changes in vascular function with aging, along with therapeutic interventions to reduce ET-mediated vascular dysfunction associated with aging. More knowledge on the factors responsible for the sex differences with vascular aging allow for optimized therapeutic strategies to attenuate CVD risk in the expanding aging population.

Association of C-Terminal Pro-Endothelin-1 with Mortality in the Population-Based KORA F4 Study

Introduction

Endothelin-1 and its prohormone C-terminal pro-endothelin-1 (CT-proET-1) have been linked to metabolic alterations, inflammatory responses and cardiovascular events in selected study populations. We analyzed the association of CT-proET-1 with cardiovascular events and mortality, carotid intima-media-thickness as surrogate for early atherosclerotic lesions, biomarkers of subclinical inflammation and adipokines in a population-based study.

Methods

The cross-sectional and prospective analyses used data from the KORA F4 study with a median follow-up time of 9.1 (8.8–9.4) years. Data on CT-proET-1 and mortality were available for 1554 participants, data on the other outcomes in subgroups (n = 596–1554). The associations were estimated using multivariable linear regression and Cox proportional hazard models adjusted for sex, age, body mass index, estimated glomerular filtration rate, arterial hypertension, diabetes, low-density and high-density lipoprotein cholesterol, current and former smoking and physical activity. The Bonferroni method was used to correct for multiple testing.

Results

In the fully adjusted model, CT-proET-1 was associated with cardiovascular (hazard ratio (HR) per standard deviation increase: 1.66; 95% confidence interval (CI): 1.10–2.51; p = 0.017) and all-cause mortality (HR: 2.03; 95% CI 1.55–2.67; p < 0.001), but not with cardiovascular events, and was inversely associated with the intima-media thickness (β: −0.09 ± 0.03; p = 0.001). CT-proET-1 was positively associated with five out of ten biomarkers of subclinical inflammation and with two out of five adipokines after correction for multiple testing. After inclusion of biomarkers of subclinical inflammation in the Cox proportional hazard model, the association of CT-proET-1 with all-cause mortality persisted (p < 0.001).

Conclusion

These results emphasize the complexity of endothelin-1 actions and/or indicator functions of CT-proET-1. CT-proET-1 is a risk marker for all-cause mortality, which is likely independent of vascular endothelin-1 actions, cardiovascular disease and inflammation.

Biomarkers for the diagnosis and management of heart failure

Heart failure (HF) is a significant cause of morbidity and mortality worldwide. Circulating biomarkers reflecting pathophysiological pathways involved in HF development and progression may assist clinicians in early diagnosis and management of HF patients. Natriuretic peptides (NPs) are cardioprotective hormones released by cardiomyocytes in response to pressure or volume overload. The roles of B-type NP (BNP) and N-terminal pro-B-type NP (NT-proBNP) for diagnosis and risk stratification in HF have been extensively demonstrated, and these biomarkers are emerging tools for population screening and as guides to the start of treatment in subclinical HF. On the contrary, conflicting evidence exists on the role of NPs as a guide to HF therapy. Among the other biomarkers, high-sensitivity troponins and soluble suppression of tumorigenesis-2 are the most promising biomarkers for risk stratification, with independent value to NPs. Other biomarkers evaluated as predictors of adverse outcome are galectin-3, growth differentiation factor 15, mid-regional pro-adrenomedullin, and makers of renal dysfunction. Multi-marker scores and genomic, transcriptomic, proteomic, and metabolomic analyses could further refine HF management.

Cardiac biomarkers for risk stratification of arrhythmic death in patients with heart failure and reduced ejection fraction

Objectives. Patients with heart failure and reduced left ventricular ejection fraction (HFrEF) are prone to ventricular tachyarrhythmias. We tested whether biomarkers C-terminal Endothelin 1 (CT-ET1), midregional pro atrial natriuretic peptide (MR-proANP) and midregional pro adrenomedullin (MR-proADM) might improve risk stratification for arrhythmic death.Methods: This prospective observational study included 160 heart failure patients with ischaemic cardiomyopathy (ICM) or non-ischaemic, dilated cardiomyopathy (DCM) and 30 control patients without heart disease. Primary endpoint was arrhythmic death (ArD) or resuscitated cardiac arrest (resCA).Results: A total of 61 patients died during the median follow-up of 7.0 [5.2-8.4] years. An ArD or resCA was observed in 48 patients. Plasma levels of CT-ET1 (p = 0.002), MR-proANP (p < 0.001) and MR-proADM (p = 0.013) were significantly higher in ICM or DCM patients compared to controls. MR-proANP levels in ICM patients were associated with a significantly increased risk for ArD or resCA (hazard ratio (HR) = 1.42, [95%CI: 1.08-1.85], p = 0.011) in a multivariable Cox regression model. Plasma levels of CT-ET1 (HR = 1.07 [0.98-1.17], p = 0.113) and MR-proADM (HR = 1.80 [0.92-3.55], p = 0.087) were not associated with ArD or resCA in ICM patients. No significant association with ArD or resCA was found in DCM patients. Multivariable Cox regression showed that CT-ET1 (HR = 1.14 [1.07-1.22], p < 0.001), MR-proANP (HR = 1.64 [1.29-2.08], p < 0.001) and MR-pro ADM (HR = 2.06 [1.12-3.77], p = 0.020) were associated with a higher risk for overall mortality.Conclusion: Patients with HFrEF had elevated levels of CT-ET1, MR-proANP and MR-proADM. Plasma levels of MR-proANP are useful as predictor for arrhythmic death in patients with ICM.

Cardiovascular Biomarkers and Calculated Cardiovascular Risk in Orally Treated Type 2 Diabetes Patients: Is There a Link?

The aim of the study was to test the correlation of serum levels of asymmetric dimethylarginine (ADMA), endothelin 1 (ET-1), N-terminal brain natriuretic pro-peptide (NT-proBNP), and placental growth factor (PIGF-1) with estimated cardiovascular (CV) risk. The study group was composed of 102 women and 67 men with type 2 diabetes, having their glycemic and metabolic parameters assessed. All were on oral antidiabetic drugs. Serum levels of NT-proBNP and PIGF-1 were measured by electro-hemi-luminescence on an Elecsys 2010 analyzer. Enzymatic immunoassays were used for ADMA and ET-1. The Framingham Risk Score (FRS), the UKPDS 2.0 and the ADVANCE risk engines were used to calculate cardiovascular risks while statistical analysis was performed on SPSS. Levels of PIGF-1 showed no correlation with the calculated CV risks. The same was true for ADMA, except for a weak correlation with the UKPDS-based 10-year risk for stroke (Pearsons's R=0.167, p=0.039). Plasma levels of ET-1 were correlated with the UKPDS-based 10-year risk for stroke (R=0.184, p=0.032) and fatal stroke (R=0.215, p=0.012) only. NT-proBNP was significantly correlated with all CV risk calculations: ADVANCE-based 4-yr risk (Spearman's Rho=0.521, p<0.001); UKPDS-based 10-year risk for: CHD (Rho=0.209, p=0.01), fatal CHD (Rho=0.282, p<0.001), stroke (Rho=0.482, p<0.001), fatal stroke (Rho=0.505, p<0.001); and 10-year FRS risk (Rho=0.246, p=0.002). In conclusion, ADMA and PIGF-1 did not seem useful in stratifying CV risk while ET-1 is linked to the risk of stroke, and NT-proBNP to all CV risk estimations.

Sympathetic nervous system activation and heart failure: Current state of evidence and the pathophysiology in the light of novel biomarkers

Heart failure (HF) is a complex clinical syndrome characterized by the activation of at least several neurohumoral pathways that have a common role in maintaining cardiac output and adequate perfusion pressure of target organs and tissues. The sympathetic nervous system (SNS) is upregulated in HF as evident in dysfunctional baroreceptor and chemoreceptor reflexes, circulating and neuronal catecholamine spillover, attenuated parasympathetic response, and augmented sympathetic outflow to the heart, kidneys and skeletal muscles. When these sympathoexcitatory effects on the cardiovascular system are sustained chronically they initiate the vicious circle of HF progression and become associated with cardiomyocyte apoptosis, maladaptive ventricular and vascular remodeling, arrhythmogenesis, and poor prognosis in patients with HF. These detrimental effects of SNS activity on outcomes in HF warrant adequate diagnostic and treatment modalities. Therefore, this review summarizes basic physiological concepts about the interaction of SNS with the cardiovascular system and highlights key pathophysiological mechanisms of SNS derangement in HF. Finally, special emphasis in this review is placed on the integrative and up-to-date overview of diagnostic modalities such as SNS imaging methods and novel laboratory biomarkers that could aid in the assessment of the degree of SNS activation and provide reliable prognostic information among patients with HF.

Differential Activation of P-TEFb Complexes in the Development of Cardiomyocyte Hypertrophy following Activation of Distinct G Protein-Coupled Receptors

Pathological cardiac hypertrophy is driven by neurohormonal activation of specific G protein-coupled receptors (GPCRs) in cardiomyocytes and is accompanied by large-scale changes in cardiomyocyte gene expression. These transcriptional changes require activity of positive transcription elongation factor b (P-TEFb), which is recruited to target genes by the bromodomain protein Brd4 or the super elongation complex (SEC). Here, we describe GPCR-specific regulation of these P-TEFb complexes and a novel mechanism for activating Brd4 in primary neonatal rat cardiomyocytes. The SEC was required for the hypertrophic response downstream of either the α₁-adrenergic receptor (α₁-AR) or the endothelin receptor (ETR). In contrast, Brd4 inhibition selectively impaired the α₁-AR response. This was corroborated by the finding that the activation of α₁-AR, but not ETR, increased Brd4 occupancy at promoters and superenhancers of hypertrophic genes. Transcriptome analysis demonstrated that the activation of both receptors initiated similar gene expression programs, but that Brd4 inhibition attenuated hypertrophic genes more robustly following α₁-AR activation. Finally, we show that protein kinase A (PKA) is required for α₁-AR stimulation of Brd4 chromatin occupancy. The differential role of the Brd4/P-TEFb complex in response to distinct GPCR pathways has potential clinical implications, as therapies targeting this complex are currently being explored for heart failure.

Plasma Endothelin-1 and Risk of Death and Hospitalization in Patients Undergoing Maintenance Hemodialysis

BACKGROUND AND OBJECTIVES

Endothelin-1 is a potent endothelium-derived vasoconstrictor peptide implicated in the pathogenesis of hypertension, congestive heart failure, and inflammation, all of which are critical pathophysiologic features of CKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

To test the hypothesis that plasma endothelin-1 levels are associated with increased risks of mortality and hospitalization in patients with chronic kidney failure, we measured plasma endothelin-1 levels in a prospective cohort of 794 individuals receiving maintenance hemodialysis. The primary outcomes were time to death and time to hospitalization.

RESULTS

The median plasma endothelin-1 level was 2.02 (interquartile range, 1.57-2.71) pg/ml. During a median follow-up period of 28 (interquartile range, 21-29) months, 253 individuals (32%) died and 643 individuals (81%) were hospitalized at least once. In multivariable models adjusted for demographic, clinical, and laboratory variables, individuals in the highest quartile of plasma endothelin-1 had a 2.44-fold higher risk of death (hazard ratio, 2.44; 95% confidence interval, 1.61 to 3.70) and a 1.54-fold higher risk of hospitalization (hazard ratio, 1.54; 95% confidence interval, 1.19 to 1.99) compared with individuals in the lowest quartile. The Harrell C-statistic of the fully adjusted model increased from 0.73 to 0.74 after addition of natural log-transformed plasma endothelin-1 (P<0.001) for all-cause mortality, and increased from 0.608 to 0.614 after addition of natural log-transformed plasma endothelin-1 (P=0.002) for hospitalization.

CONCLUSIONS

Higher plasma endothelin-1 is associated with adverse clinical events in patients receiving hemodialysis independent of previously described risk factors.

PODCAST

This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2020_05_15_CJN11130919.mp3.

Big endothelin-1 as a clinical marker for ventricular tachyarrhythmias in patients with post-infarction left ventricular aneurysm

Objective:

Ventricular tachyarrhythmia is the leading cause of death in post-infarction patients. Big endothelin-1 (ET-1) is a potent vasoconstrictor peptide and plays a role in ventricular tachyarrhythmia development. The aim of this study was to investigate the association between the serum concentration of big ET-1 and ventricular tachyarrhythmia in post-infarction left ventricular aneurysm (PI-LVA) patients.

Methods:

A total of 222 consecutive PI-LVA patients who had received medical therapy were enrolled in the study. There were 43 (19%) patients who had ventricular tachycardia/ventricular fibrillation (VT/VF) at the time of admission. The clinical characteristics were observed and the plasma big ET-1 level was measured. Associations between big ET-1 and the presence of VT/VF were assessed. Patients were followed up to check for outcomes related to cardiovascular mortality, VT/VF attack, and all-cause mortality.

Results:

The median concentration of big ET-1 was 0.635 pg/mL. Patients with big ET-1 concentrations above the median were more likely to have higher risk clinical features. There was a positive correlation between the level of big ET-1 with VT/VF attack (r=0.354, p<0.001). In the multiple logistic regression analysis, big ET-1 (OR=4.06, 95%CI:1.77-9.28, p<0.001) appeared as an independent predictive factor for the presence of VT/VF. Multiple Cox regression analysis suggested that big ET-1 concentration was independently predictive of VT/VF attack (OR=2.5, 95% CI 1.4–4.5, p<0.001). NT-proBNP and left ventricular ejection fraction of ≤35% were demonstrated to be independently predictive of cardiovascular mortality and all-cause mortality.

Conclusion:

Increased big ET-1 concentration in PI-LVA patients is a valuable independent predictor for the prevalence of ventricular tachyarrhythmias and VT/VF attacks during follow-up after PI-LVA treatment.

Serum parathyroid hormone levels in patients with chronic right heart failure

Parathyroid hormone (PTH) is a novel cardiovascular biomarker which is particularly useful for detection and assessment of heart failure (HF). However, previous studies examining PTH in heart failure have primarily focused on left HF; thus, the relationship between PTH and right HF remains unclear. The aim of the present study was to evaluate the serum PTH levels in patients with chronic right HF. A total of 154 patients with chronic right HF were enrolled in the present study. A binary logistic regression analysis model was used to assess the independent predictive value of PTH levels in chronic right HF. Partial correlative analysis was used to demonstrate the relevance of PTH levels on the parameters of assessment of right heart function. A multiple linear regression analysis model was used to evaluate the independent factors of PTH levels in patients with right HF. The results showed that the serum PTH levels in the right HF group were significantly higher compared with the control group. After adjusting for predictors of right HF, serum PTH levels were associated with right HF with an odds ratio of 1.066 (95% confidence interval: 1.030-1.102, P<0.001. Serum PTH levels were independently correlated with plasma N-terminal pro-B-type natriuretic peptide levels, right ventricular end-diastolic diameter and severity of lower extremity edema (all P<0.05). Therefore, based on the results of the present study, PTH may be a useful biomarker for detection and assessment of right HF.

Endothelin-1, cardiac morphology, and heart failure: the MESA angiogenesis study

BACKGROUND

Circulating levels of endothelin-1 (ET1) are elevated in heart failure and predict poor prognosis. However, it is not clear whether ET1 elevation is an adaptive response, maladaptive response, or an epiphenomenon of heart failure. In this study, we evaluated the relationships between ET1, cardiac morphology, and incident heart failure or cardiovascular death in participants with no evidence of clinical cardiovascular disease at the time ET1 was measured.

METHODS AND RESULTS

ET1 was measured in 1,361 participants in the Multi-Ethnic Study of Atherosclerosis Angiogenesis Sub-Study. As suggested by linear regression, participants with lower circulating ET1 levels tended to be older, non-white, more likely to have smoked heavily, and less likely to report intentional exercise. Participants with higher ET1 levels had smaller left ventricular end-diastolic volumes (8.9 ml smaller per log increase in ET1, 95% confidence interval 17.1-0.7, p = 0.03) with an increased left ventricular ejection fraction (2.8% per log increase in ET1, 95% confidence interval 0.5%-5.2%, p = 0.02). As suggested by Cox Proportional Hazards estimates, participants with higher ET1 levels had a lower risk for the composite outcome of heart failure or cardiovascular death in models that were unadjusted or had limited adjustment (p = 0.03 and p = 0.05, respectively). Lower risk for heart failure with higher ET1 levels could not be clearly shown in a model including health behaviors.

CONCLUSIONS

These results suggest, but do not confirm, that elevated levels of circulating ET1 are associated with a more favorable cardiac phenotype. The relationship between ET1 and outcomes was not fully independent of one or more covariates.

Cardiovascular biomarkers predict post-discharge re-hospitalization risk and mortality among Swedish heart failure patients

AIM

The aim of this study was to assess the predictive role of biomarkers, associated with cardiovascular stress and its neuroendocrine response as well as renal function, in relation to mortality and risk of re-hospitalization among consecutive patients admitted because of heart failure (HF).

METHODS AND RESULTS

A total of 286 patients (mean age, 75 years; 29% women) hospitalized for newly diagnosed or exacerbated HF were analysed. Associations between circulating levels of mid-regional pro-adrenomedullin (MR-proADM), copeptin, C-terminal pro-endothelin-1, N-terminal pro-brain natriuretic peptide (NT-proBNP), cystatin C, and all-cause mortality as well as risk of re-hospitalization due to cardiac causes were assessed using multivariable Cox regression models. A two-sided Bonferroni-corrected P-value of 0.05/5 = 0.010 was considered statistically significant. All biomarkers were related to echocardiographic measurements of cardiac dimensions and function. A total of 57 patients died (median follow-up time, 17 months). In the multivariable-adjusted Cox regression analyses, all biomarkers, except C-terminal pro-endothelin-1, were significantly associated with increased mortality: NT-proBNP [hazard ratio (HR) 1.85, 95% confidence interval (CI) 1.17-2.17; P = 4.0 × 10^-4 ], MR-proADM (HR 1.94, 95% CI 1.36-2.75; P = 2.2 × 10^-4 ), copeptin (HR 1.70, 95% CI 1.22-2.36; P = 0.002), and cystatin C (HR 2.11, 95% CI 1.56-2.86; P = 1.0 × 10^-6 ). A total of 90 patients were re-hospitalized (median time to re-hospitalization, 5 months). In multivariable Cox regression analyses, NT-proBNP was the only biomarker that showed significant association with risk of re-hospitalization due to cardiac causes (HR 1.43, 95% CI 1.10-1.87; P = 0.009).

CONCLUSIONS

Among patients hospitalized for HF, elevated plasma levels of NT-proBNP, MR-proADM, copeptin, and cystatin C are associated with higher mortality after discharge, whereas NT-proBNP is the only biomarker that predicts the risk of re-hospitalization due to cardiac causes.