Prognostic value of sST2 added to BNP in acute heart failure with preserved or reduced ejection fraction

Correlations between soluble ST2 concentration and the nutritional status in patients with heart failure with reduced ejection fraction - cross-sectional study

BACKGROUND

Heart failure (HF) is a global problem that stimulates research on markers associated with the diagnosis and course of the disease. Soluble suppression of tumorigenicity-2 (sST2) is a receptor for interleukin-33 and is associated with increased mortality rates in HF patients. Malnutrition in HF is also connected with inflammation and is associated with worse prognosis. The present study aimed to evaluate the relationship between sST2 concentration and the nutritional status of patients with HF with reduced ejection fraction (HFrEF).

MATERIAL AND METHODS

138 patients with HFrEF were enrolled in this cross-sectional study. Nutritional status was assessed using Geriatric Nutritional Risk Index (GNRI) and Controlling Nutritional Status (CONUT). The mean age was 53.6 ± 10.8 years.

RESULTS

In the group with sST2 > 32.9 ng/mL, the GNRI score was higher and the associated risk of malnutrition was more common (29% vs. 12%; p = 0.011). Coherently in the group with sST2 > 32.9 ng/mL the median CONUT score was worse (2 [IQR 1-3] vs. 1 [IQR 0-2]; p = 0.0016) and the risk of malnutrition defined by this tool was also more prevalent (p = 0.0079). This relationship was independent of the concentration of natriuretic peptides, age and sex.

CONCLUSIONS

According to available research, this research is the first study showing that sST2 concentration is related with nutritional status in HFrEF patients. sST2 may help to evaluate the necessity for nutritional intervention in HFrEF patients.

Soluble ST2 in Heart Failure: A Clinical Role beyond B-Type Natriuretic Peptide

Soluble (s)ST2 has been proposed as a useful biomarker for heart failure (HF) patient management. Myocardial damage or mechanical stress stimulate sST2 release. ST2 competes with a membrane bound receptor (ST2 ligand, or ST2L) for interleukin-33 (IL-33) binding, inhibiting the effects induced by the ST2L/IL-33 interaction so that excessive sST2 may contribute to myocardial fibrosis and ventricular remodeling. Compared to natriuretic peptides (NPs), sST2 concentration is not substantially affected by age, sex, body mass index, kidney function, atrial fibrillation, anemia, or HF etiology, and has low intra-individual variation. Its prognostic role as an independent marker is well reported in the literature. However, there is a gap on its use in combination with NPs, currently the only biomarkers recommended by European and American guidelines for HF management. Reflecting the activation of two distinct biological systems, a benefit from the use of sST2 and NP in combination is advocated. The aim of this review is to report the current scientific knowledge on sST2 in the acute and chronic HF settings with a particular attention to its additive role to natriuretic peptides (NPs).

Galectin-3 changes from admission to discharge and its prognostic value for in-hospital mortality in heart failure: A prospective observational study

The aim of this study was to compare the levels of Galectin-3 (Gal-3) in heart failure patients at admission and discharge, and to evaluate the ability of Gal-3 at admission in predicting in-hospital mortality. A total of 111 patients were enrolled. Gal-3 and B-type natriuretic peptide (BNP) levels were measured at admission and discharge. Receiver operating characteristic analysis was used to determine the optimal cutoff values for Gal-3 and BNP, and logistic regression was used to assess the predictive ability of these biomarkers for in-hospital mortality. Gal-3 levels at discharge (24.08 ± 9.55) were significantly lower than those at admission (30.71 ± 11.22). The majority of patients (72.07%) experienced a decrease in Gal-3 levels, with a median reduction of 19.9% (interquartile range [IQR] 8.7-29.8). Gal-3 levels showed a weak correlation with BNP levels both at admission and discharge. Combining Gal-3 and BNP significantly improved the ability to predict in-hospital mortality, and including heart failure stage as a third predictor further improved the predictive accuracy. The optimal cutoff values for Gal-3 and BNP to predict in-hospital mortality were identified as 28.1 ng/mL and 1782.6 pg/mL, respectively, with moderate to good sensitivity and specificity. A median reduction of 19.9% of Gal-3 may indicate possibility to discharge. Our findings suggest that Gal-3 and BNP, when combined with heart failure stage, may be useful for predicting in-hospital mortality.

Growth stimulation expressed gene 2 (ST2): Clinical research and application in the cardiovascular related diseases

As an interleukin (IL)-1 receptor family member, scientists found that when circulating soluble growth stimulation expressed gene 2 (sST2) is low, its ligand, IL-33, will bind to ST2L to exert protective effects on various types of cells. On the other hand, competitive binding of IL-33 occurs when sST2 concentrations are increased, followed by a reduction in the amount available for cell protection. Based on this mechanism, the usage of sST2 is to identify the population of high-risk patients with cardiovascular disease. In recent years, the role of serum sST2 in the occurrence, diagnosis, prognosis, and treatment of cardiovascular diseases has been gradually accepted by doctors. This manuscript systemically reviews the biological functions and applications of sST2 in disease diagnosis and treatment, especially for cardiovascular diseases. In clinical testing, since IL-33 can negatively impact sST2 measurement accuracy, the properties of current assay kits have been summarized and discussed to provide a clear view of the clinical chemistry results. Although sST2 is a promising biomarker, there are few quantitative approaches available for clinical testing. In this context, a mass spectrometry (MS)-based approach might be an option, as this is a powerful analytical tool to distinguish structurally related molecules in the matrix and decrease false-positive results in clinical testing. Moreover, approaches developed based on MS would be an ideal way to further study sST2 standardization.

Diagnostic and prognostic value of serum soluble suppression of tumorigenicity-2 in heart failure with preserved ejection fraction: A systematic review and meta-analysis

Background

Heart failure (HF) with preserved ejection fraction (HFpEF) is a growing public health burden, with mortality and rehospitalization rates comparable to HF with reduced ejection fraction (HFrEF). The evidence for the clinical usefulness of soluble suppression of tumorigenicity 2 (sST2) in HFpEF is contradictory. Therefore, we conducted the following systematic review and meta-analysis to assess the diagnostic and prognostic value of serum sST2 in HFpEF.

Methods

PubMed and Scopus were searched exhaustively from their inception until March 15, 2022. In diagnostic analysis, we compared the diagnostic value of serum sST2 in HFpEF to NT pro-BNP. We separately pooled the unadjusted and multivariate-adjusted hazard ratios (HRs) and the corresponding 95% confidence intervals (CIs) in prognostic analysis.

Results

A total of 16 publications from 2008 to 2021 were examined. The results of this analysis were as follow: Firstly, compared with NT pro-BNP, sST2 obtains poor diagnostic performance in independently identifying HFpEF from healthy controls, hypertensive patients, and HFrEF patient. Nevertheless, it may provide incremental value to other biomarkers for diagnosing HFpEF and deserves further investigation. Secondly, log sST2 was independently associated with adverse endpoints on multivariable analysis after adjusting for variables such as age, sex, race, and NYHA class. Per log unit rise in sST2, there was a 2.76-fold increased risk of all-cause death [HR:2.76; 95% CI (1.24, 6.16); p = 0.516, I² = 0%; P = 0.013] and a 6.52-fold increased risk in the composite endpoint of all-cause death and HF hospitalization [HR:6.52; 95% CI (2.34, 18.19); p = 0.985, I² = 0%; P = 0.000]. Finally, the optimal threshold levels of serum sST2 need further determined.

Conclusions

Higher sST2 was strongly linked to an increased risk of adverse outcomes in HFpEE. Especially, log sST2 independently predicted all-cause death and the composite endpoint of all-cause death and HF hospitalization. However, prospective and multicenter studies with large-sample and extended follow-up periods are required to validate our results due to limitations in our research.

The Translation and Commercialisation of Biomarkers for Cardiovascular Disease—A Review

As a leading cause of mortality and morbidity worldwide, cardiovascular disease and its diagnosis, quantification, and stratification remain significant health issues. Increasingly, patients present with cardiovascular disease in the absence of known risk factors, suggesting the presence of yet unrecognized pathological processes and disease predispositions. Fortunately, a host of emerging cardiovascular biomarkers characterizing and quantifying ischaemic heart disease have shown great promise in both laboratory settings and clinical trials. These have demonstrated improved predictive value additional to widely accepted biomarkers as well as providing insight into molecular phenotypes beneath the broad umbrella of cardiovascular disease that may allow for further personalized treatment regimens. However, the process of translation into clinical practice – particularly navigating the legal and commercial landscape – poses a number of challenges. Practical and legal barriers to the biomarker translational pipeline must be further considered to develop strategies to bring novel biomarkers into the clinical sphere and apply these advances at the patient bedside. Here we review the progress of emerging biomarkers in the cardiovascular space, with particular focus on those relevant to the unmet needs in ischaemic heart disease.

Serum Soluble ST2 Is a Valuable Prognostic Biomarker in Patients With Acute Heart Failure

Background

This study aimed to investigate the clinical utility of different soluble suppression of tumorigenicity 2 (sST2) levels in assessing the severity and prognosis of patients with acute heart failure (AHF).

Methods

This was a prospective cohort study. Three hundred and thirty-one consecutively enrolled AHF patients from March 2018 to November 2019 were divided into 3 subgroups according to sST2 levels: T1 (1.15–7.70 ng/ml; N = 110), T2 (7.71–17.24 ng/ml; N = 111), and T3 (17.26–47.42 ng/ml; N = 110). The patients were followed up for a median period of 21.0 months for the development of the primary endpoint. Cox proportional hazards model was performed to evaluate the prognostic value of sST2 for the clinical outcomes.

Results

The mean age of patients was 69 years (range, 34–93 years), and 70.4% were male. During the follow-up period, 63 participants died. Patients with higher sST2 levels had lower left ventricular ejection fraction (correlation = −0.119, P = 0.031), and higher New York Heart Association classification (correlation = 0.443, P < 0.001) and N-terminal pro-B type natriuretic peptide (NT-proBNP) levels (correlation = 0.392, P < 0.001). Higher sST2 was also associated with creatinine, urea nitrogen, hemoglobin, and left ventricular mass index. Multivariate analysis revealed that sST2 (per log unit, hazard ratio: 2.174, 95% confidence interval [CI] 1.012–4.67, P = 0.047) and NT-proBNP (per log unit, HR 2.171, 95%CI 1.169–4.032, P < 0.001) were independent risk factors for the primary outcome in all patients with AHF.

Conclusion

sST2 can provide prognostic information in AHF. The higher the sST2 level in patients with AHF, the higher the incidence of cardiovascular death.

Dynamics of growth differentiation factor 15 in acute heart failure

Aims

Risk stratification in acute heart failure (HF) patients can help to decide therapies and time for discharge. The potential of growth differentiation factor 15 (GDF‐15) in HF has been previously shown. We aimed to study the importance of GDF‐15‐level variations in acute HF patients.

Methods and results

We retrospectively evaluated a cohort of patients hospitalized due to acute HF. GDF‐15 was measured both at admission and on the discharge day. Patients were followed‐up during a 3 year period. The endpoint under analysis was all‐cause mortality. GDF‐15 variation is equal to [(admission GDF‐15 − discharge GDF‐15)∕admission GDF‐15] × 100. Variation was categorized in levels of increase or decrease of GDF‐15. Patients were cross‐classified according to admission and discharge GDF‐15 cut‐off points. A Cox regression analysis was used to assess the prognostic impact of GDF‐15 variation and the impact of both admission and discharge GDF‐15 according to the cross‐classification. We studied a group of 249 patients with high co‐morbidity burden. Eighty‐one patients died at 1 year and 147 within 3 years. There was a modest decrease in GDF‐15 during hospitalization from a median value of 4087 to 3671 ng/mL (P = 0.02). No association existed between GDF‐15 variation and mortality. In multivariate analysis, patients with admission GDF‐15 ≥ 3500 ng/mL and discharge GDF‐15 ≥ 3000 ng/mL had a significantly higher 1 year death risk when compared with the remaining—hazard ratio = 2.59 (95% confidence interval: 1.41–4.76)—and a 3 year 1.76 (95% confidence interval: 1.08–2.87) higher death risk compared with those with both values below the cut‐off.

Conclusions

Growth differentiation factor 15 decreased during an acute HF hospitalization, but its variation had no prognostic implications. The knowledge of both admission and discharge GDF‐15 added meaningful information to patients' risk stratification.

Reappraisal of Inflammatory Biomarkers in Heart Failure

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

Innate Lymphoid Cells Play a Pathogenic Role in Pericarditis

We find that cardiac group 2 innate lymphoid cells (ILC2s) are essential for the development of IL-33-induced eosinophilic pericarditis. We show a pathogenic role for ILC2s in cardiac inflammation, in which ILC2s activated by IL-33 drive the development of eosinophilic pericarditis in collaboration with cardiac fibroblasts. ILCs, not T and B cells, are required for the development of pericarditis. ILC2s transferred to the heart of Rag2^-/-Il2rg^-/- mice restore their susceptibility to eosinophil infiltration. Moreover, ILC2s direct cardiac fibroblasts to produce eotaxin-1. We also find that eosinophils reside in the mediastinal cavity and that eosinophils transferred to the mediastinal cavity of eosinophil-deficient ΔdblGATA1 mice following IL-33 treatment migrate to the heart. Thus, the serous cavities may serve as a reservoir of cardiac-infiltrating eosinophils. In humans, patients with pericarditis show higher amounts of ILCs in pericardial fluid than do healthy controls and patients with other cardiac diseases. We demonstrate that ILCs play a critical role in pericarditis.

Suppression of Tumourigenicity 2 in Heart Failure With Preserved Ejection Fraction

Heart failure (HF), with steadily increasing incidence rates and mortality in an ageing population, represents a major challenge. Evidence suggests that more than half of all patients with a diagnosis of HF suffer from HF with preserved ejection fraction (HFpEF). Emerging novel biomarkers to improve and potentially guide the treatment of HFpEF are the subject of discussion. One of these biomarkers is suppression of tumourigenicity 2 (ST2), a member of the interleukin (IL)-1 receptor family, binding to IL-33. Its two main isoforms – soluble ST2 (sST2) and transmembrane ST2 (ST2L) – show opposite effects in cardiovascular diseases. While the ST2L/IL-33 interaction is considered as being cardioprotective, sST2 antagonises this beneficial effect by competing for binding to IL-33. Recent studies show that elevated levels of sST2 are associated with increased mortality in HF with reduced ejection fraction. Nevertheless, the significance of sST2 in HFpEF remains uncertain. This article aims to give an overview of the current evidence on sST2 in HFpEF with an emphasis on prognostic value, clinical association and interaction with HF treatment. The authors conclude that sST2 is a promising biomarker in HFpEF. However, further research is needed to fully understand underlying mechanisms and ultimately assess its full value.

Prognostic value of sST2 in patients with heart failure with reduced, mid-range and preserved ejection fraction

BACKGROUNDS

Prognostic value of soluble suppression of tumorigenecity (sST2), a novel circulating biomarker for myocardial fibrosis, remains elusive in the heart failure patients with preserved ejection fraction (HFpEF).

METHODS

405 consecutive patients with heart failure (HF) were enrolled prospectively, and were grouped into HF with reduced ejection fraction (HFrEF, N = 215), HF with mid-range ejection fraction (HFmrEF, N = 80) and HFpEF (N = 110). The primary endpoint was the composite endpoint of all-cause death and HF rehospitalization.

RESULTS

After a median of 12 months, 139 patients reached the primary endpoint, with 57 patients died and 82 patients rehospitalized. Multivariate analysis confirmed that sST2 was an independent risk factor of the primary endpoint for all HF patients [hazard ratio (HR) 2.35, 95% confidence interval (CI) 1.30-4.22, P = 0.004]. Predicting efficacy of sST2 on outcomes was higher for HFpEF (HR 6.48, 95%CI 1.89-22.21, P = 0.003) as compared to HFrEF (HR 3.21, 95% CI 1.67-6.19, P = 0.000). But the association between sST2 and outcomes in HFmrEF is not statistical (HR 3.38, 95%CI 0.82-13.86, P = 0.091). The combined use of sST2 and N terminal pro B type natriuretic peptide (NT-proBNP) could improve the prognostic value compared to using NT-proBNP alone in HFrEF (AUC = 0.794 vs. 0.752, P = 0.034).

CONCLUSION

Higher baseline sST2 levels are associated with increased risk of all-cause death and HF rehospitalization in patients with HF independent of ejection fraction. The combined use of sST2 and NT-proBNP could improve the prognostic value than using these two values alone, especially for HFrEF patients.

The Predictive Role for ST2 in Patients with Acute Coronary Syndromes and Heart Failure

Intensive research has shed light on the utilization of novel biomarkers which facilitate the diagnosis and prognosis of patients with different medical problems. One of the most important biomarkers especially in the spectrum of heart failure is soluble ST2 (sST2: soluble Suppression of Tumorigenicity 2), which is involved in inflammation, fibrosis and cardiac stress. In the revised 2017 ACC/AHA/HFSA, "Focused Update Guidelines for the Management of Heart Failure" ST2 was given a class-IIa recommendation for the optimal risk assessment in patients with heart failure. Many studies indicate that not only baseline but also serial measurements of ST2 can accurately predict future cardiovascular events in patients with Acute Coronary Syndromes and heart failure. Therefore, in this review, we are going to discuss the studies about the prognostic significance of ST2 in patients with Acute Coronary Syndromes, acute and chronic heart failure.

sST2 as a value-added biomarker in heart failure

Soluble suppression of tumorigenicity-2 (sST2) is a biomarker widely investigated during the last few years. Its role has become clear in pathological conditions such as fibrosis and inflammation. From translational research to laboratory medicine, considerable efforts have been made to elucidate the features of sST2 biomarker and to consider its contribution to HF management. In this review, we summarized the results from recent works concerning sST2, and particularly we focused on the interest of sST2 in conditions for which classical biomarkers value interpretation is misleading. Indeed, despite other HF biomarkers, sST2 was proved to be independent from common comorbidities such as renal dysfunction and hypertension. Thus, sST2 showed promise for a combined strategy with natriuretic peptides, mainly for specific categories of patients. Particular attention was paid to findings on sST2 in HF with preserved ejection fraction (HFpEF), a form of HF for which reliable and specific biomarkers are awaited. Finally, a place is reserved to sST2 kinetics from basal to follow up values in order to improve clinical decision making and to customize patient treatments.

Dynamics of the Ghrelin/Growth Hormone Secretagogue Receptor System in the Human Heart Before and After Cardiac Transplantation

Currently, the early preclinical detection of left ventricular dysfunction is difficult because biomarkers are not specific for the cardiomyopathic process. The underlying molecular mechanisms leading to heart failure remain elusive, highlighting the need for identification of cardiac-specific markers. The growth hormone secretagogue receptor (GHSR) and its ligand ghrelin are present in cardiac tissue and are known to contribute to myocardial energetics. Here, we examined tissue ghrelin-GHSR levels as specific markers of cardiac dysfunction in patients who underwent cardiac transplantation. Samples of cardiac tissue were obtained from 10 patients undergoing cardiac transplant at the time of organ harvesting and during serial posttransplant biopsies. Quantitative fluorescence microscopy using a fluorescent ghrelin analog was used to measure levels of GHSR, and immunofluorescence was used to measure levels of ghrelin, B-type natriuretic peptide (BNP), and tissue markers of cardiomyocyte contractility and growth. GHSR and ghrelin expression levels were highly variable in the explanted heart, less in the grafted heart biopsies. GHSR and ghrelin were strongly positively correlated, and both markers were negatively correlated with left ventricular ejection fraction. Ghrelin had stronger positive correlations than BNP with the signaling markers for contractility and growth. These data suggest that GHSR-ghrelin have potential use as an integrated marker of cardiac dysfunction. Interestingly, tissue ghrelin appeared to be a more sensitive indicator than BNP to the biochemical processes that are characteristic of heart failure. This work allows for further use of ghrelin-GHSR to interrogate cardiac-specific biochemical mechanisms in preclinical stages of heart failure (HF).

Protein biomarkers for cardiorenal syndrome

INTRODUCTION

The term cardiorenal syndrome (CRS) describes the progressive pathology and interactions that develop upon heart and kidney failure. The definition of CRS is not firmly established and has evolved gradually during the last decade. The main clinical challenges associated with CRS are the lack of tools for early disease diagnosis and the inability to predict the development of cardiorenal pathophysiology. Currently several biomarkers have been proposed for improving CRS patient management. However, validation studies are needed to implement these initial findings to the clinical setting. Areas covered: In this review the database PubMed was used for a literature search on the definition and classification of CRS as well as biomarkers for CRS diagnosis and prognosis. Expert opinion: A universally acceptable classification system for CRS is not available. Thus, acquiring mechanistic insights relative to the pathophysiology of the disease is challenging. Reported biomarkers include well-established markers for heart/renal dysfunction and inflammation. Some proteins expressed in both organs have also been associated with CRS, yet their link to disease pathophysiology and organ cross-talk is missing. Establishing the link between deregulated molecular pathways and CRS phenotypes is required to define biological relevance of existing findings and ultimately biology-driven markers and targets.

Circulating biomarkers of left ventricular hypertrophy in pediatric coarctation of the aorta

OBJECTIVE

Patients undergoing surgical repair of aortic coarctation have a 50% risk of pathologic left ventricular remodeling (increased left ventricular mass or relative wall thickness). Endothelin 1, ST2, galectin 3, norepinephrine and B-natriuretic peptide are biomarkers that have been associated with pathologic LV change in adult populations but their predictive value following pediatric coarctation repair are not known.

HYPOTHESIS

Biomarker levels at coarctation repair will predict persistent left ventricular remodeling at 1-year follow up.

DESIGN

Prospective, cohort study of 27 patients' age 2 days-12 years with coarctation of the aorta undergoing surgical repair. Echocardiograms were performed preoperation, postoperation, and at 1-year follow-up. Plasma biomarker levels were measured at the peri-operative time points. Association between biomarker concentrations and echocardiographic parameters was assessed.

RESULTS

Neither left ventricular mass index nor relative wall thickness varied from pre-op to post-op. At pre-op, relative wall thickness was elevated in 52% and left ventricular mass index was elevated in 22%; at follow-up, relative wall thickness was elevated in 13% and left ventricular mass index was elevated in 8%. Presence of residual coarctation did not predict left ventricular remodeling (AUC 0.59; P > .05). Multivariable receiver operating characteristic curve combining pre-op ST2 and endothelin 1 demonstrated significant predictive ability for late pathologic left ventricular remodeling (AUC 0.85; P = .02).

CONCLUSIONS

Persistent left ventricular hypertrophy and abnormal relative wall thickness at intermediate-term follow-up was rare compared to previous studies. A model combining pre-op endothelin 1 and ST2 level demonstrated reasonable accuracy at predicting persistent abnormalities in this cohort. Larger studies will be needed to validate this finding and further explore the mechanism of persistent left ventricular remodeling in this population.

Redefining biomarkers in heart failure

Heart failure (HF) is the end result of many different cardiac and non-cardiac abnormalities leading to a complex clinical entity. In this view, the use of biomarkers in HF should be deeply reconsidered; indeed, the same biomarker may carry a different significance in patients with preserved or reduced EF. The aim of this review is to reconsider the role of biomarkers in HF, based on the different clinical characteristics of this syndrome. The role of cardiac and non-cardiac biomarkers will be reviewed with respect of the different clinical manifestations of this syndrome.

Pathophysiology of acute heart failure syndrome: a knowledge gap

Although much remains unknown regarding the pathophysiology of acute heart failure (AHF), precipitating events are thought to involve a complex set of interactions between the heart, kidneys, and peripheral vasculature. In addition to these interactions, which are considered the primary abnormalities in patients with AHF, several other organ systems may also be affected and contribute to disease progression. Currently available scientific literature suggests that the natural history and pathophysiology of AHF consists of two phases: (1) an "initiation phase" involving a series of triggering events, and (2) an "amplification phase," in which multiple mechanisms contribute to worsening HF and exacerbate end-organ damage. Biomarkers of cardiac, renal, pulmonary, and other organ function have been identified during episodes of AHF, including brain natriuretic peptide, troponin I, and troponin T; biomarkers associated with AHF have proven to be useful tools for studying the pathophysiology of the syndrome, predicting clinical outcomes, and identifying patient management strategies. Despite considerable advances in recent years, AHF continues to be a leading cause of hospitalization and death in patients with chronic HF. Moreover, AHF remains a major healthcare issue exacting a considerable cost burden. Addressing this ongoing unmet need requires prioritizing efforts to better understand the natural history and pathophysiology of AHF; only then can targeted therapies be developed to prevent rehospitalization in patients with AHF, or at least alter the trajectory of disease progression toward improved clinical outcomes.

Non-natriuretic peptide biomarkers in heart failure with preserved and reduced ejection fraction

Heart failure (HF) with reduced and preserved ejection fraction constitutes two entities with distinct pathogenetic backgrounds sharing common features. Beyond natriuretic peptides, several novel biomarkers have been proven useful in the diagnosis, prognosis and treatment of HF. Biomarkers of myocardial fibrosis have a low diagnostic yield in subjects with acute HF but may add prognostic information, especially in patients with HF and preserved ejection fraction. Biomarkers of renal impairment identify subjects with worse prognosis independently of left ventricle ejection fraction while inflammatory markers have not been proven useful in patients with systolic or diastolic impairment. In this review article, we summarize the main differences and application of non-natriuretic peptide biomarkers in HF patients with preserved and reduced ejection fraction.

Biomarkers, myocardial fibrosis and co-morbidities in heart failure with preserved ejection fraction: an overview

The prevalence of heart failure with preserved ejection fraction (HFpEF) is steadily increasing. Its diagnosis remains difficult and controversial and relies mostly on non-invasive echocardiographic detection of left ventricular diastolic dysfunction and elevated filling pressures. The large phenotypic heterogeneity of HFpEF from pathophysiologic al underpinnings to clinical manifestations presents a major obstacle to the development of new therapies targeted towards specific HF phenotypes. Recent studies suggest that natriuretic peptides have the potential to improve the diagnosis of early HFpEF, but they still have significant limitations, and the cut-off points for diagnosis and prognosis in HFpEF remain open to debate. The purpose of this review is to present potential targets of intervention in patients with HFpEF, starting with myocardial fibrosis and methods of its detection. In addition, co-morbidities are discussed as a means to treat HFpEF according to cut-points of biomarkers that are different from usual. Biomarkers and approaches to co-morbidities may be able to tailor therapies according to patients' pathophysiological needs. Recently, soluble source of tumorigenicity 2 (sST2), growth differentiation factor 15 (GDF-15), galectin-3, and other cardiac markers have emerged, but evidence from large cohorts is still lacking. Furthermore, the field of miRNA is a very promising area of research, and further exploration of miRNA may offer diagnostic and prognostic applications and insight into the pathology, pointing to new phenotype-specific therapeutic targets.

Soluble ST2 in Heart Failure

Suppression of tumorigenicity 2 (ST2) is a member of the interleukin (IL)-1 receptor family, whose role was originally established in the context of inflammatory and autoimmune diseases. More recently, testing for ST2 has been used in the setting of cardiovascular disease. The soluble form of ST2 is a decoy receptor that inhibits beneficial cardioprotective effects of IL-33; such inhibition results in cardiac hypertrophy, myocardial fibrosis, and ventricular dysfunction. Measurement of soluble ST2 has utility for assessing heart failure severity and prognosis. In this review, we examine the role of soluble ST2 in both acute and chronic heart failure.

Prognostic value of sST2 and NT-proBNP at admission in heart failure with preserved, mid-ranged and reduced ejection fraction

OBJECTIVE

The aim of this study was to compare sST2 at admission with N-terminal pro B-type natriuretic peptide (NT-proBNP) in prognostic accuracy among different types of heart failure (HF) and clarifying the enhanced prognostic value in patients with HF by the combination of the two biomarkers.

METHODS AND RESULTS

A total of 164 consecutive patients admitted to our institution for HF were divided into three groups of HF with reduced ejection fraction (HFrEF), HF with mid-range ejection fraction (HFmrEF) and HF with preserved ejection fraction (HFpEF). Circulating sST2 and NT-proBNP were measured using the enzyme-linked immunosorbent assay (ELISA). The sST2 level was only significantly higher in HFrEF when compared with HFpEF. At ROC analysis to one-year adverse events, only sST2 showed predictive value in HFmrEF with an optimal cut-off value of 147.66 ng/ml (AUC 0.697, p = .045, sensitivity 75%, specificity 75.8%), while both NT-proBNP and sST2 showed a significant predictive value in HFpEF (p = .036 vs .042; AUC 0.683, sensitivity 71.4%, specificity 55.6%; AUC 0.677, sensitivity 64.3%, specificity 83.3%) with an optimal cut-off value of 1054.50 pg/ml and 117.80 ng/ml. Multivariate regression analysis suggested that sST2 and NT-proBNP could be biomarkers for predicting 1-year adverse events of HF (OR = 4.384, 95% CI = 1.661-11.570 vs. OR = 3.451, 95% CI = 1.254-9.497). Adverse events occurred frequently within one year both in sST2 and in NT-proBNP above the median.

CONCLUSIONS

sST2 can provide different prognostic information in distinct types of HF, and even be superior to NT-proBNP. sST2 combined with NT-proBNP can improve predicting accuracy.

Inflammatory Biomarkers Predict Heart Failure Severity and Prognosis in Patients With Heart Failure With Preserved Ejection Fraction: A Holistic Proteomic Approach

BACKGROUND

Underlying mechanisms in heart failure (HF) with preserved ejection fraction remain unknown. We investigated cardiovascular plasma biomarkers in HF with preserved ejection fraction and their correlation to diastolic dysfunction, functional class, pathophysiological processes, and prognosis.

METHODS AND RESULTS

In 86 stable patients with HF and EF ≥45% in the Karolinska Rennes (KaRen) biomarker substudy, biomarkers were quantified by a multiplex immunoassay. Orthogonal projection to latent structures by partial least square analysis was performed on 87 biomarkers and 240 clinical variables, ranking biomarkers associated with New York Heart Association (NYHA) Functional class and the composite outcome (all-cause mortality and HF hospitalization). Biomarkers significantly correlated with outcome were analyzed by multivariable Cox regression and correlations with echocardiographic measurements performed. The orthogonal partial least square outcome-predicting biomarker pattern was run against the Ingenuity Pathway Analysis (IPA) database, containing annotated data from the public domain. The orthogonal partial least square analyses identified 32 biomarkers correlated with NYHA class and 28 predicting outcomes. Among outcome-predicting biomarkers, growth/differentiation factor-15 was the strongest and an additional 7 were also significant in Cox regression analyses when adjusted for age, sex, and N-terminal probrain natriuretic peptide: adrenomedullin (hazard ratio per log increase 2.53), agouti-related protein; (1.48), chitinase-3-like protein 1 (1.35), C-C motif chemokine 20 (1.35), fatty acid-binding protein (1.33), tumor necrosis factor receptor 1 (2.29), and TNF-related apoptosis-inducing ligand (0.34). Twenty-three of them correlated with diastolic dysfunction (E/e') and 5 with left atrial volume index. The IPA suggested that increased inflammation, immune activation with decreased necrosis and apoptosis preceded poor outcome.

CONCLUSIONS

In HF with preserved ejection fraction, novel biomarkers of inflammation predict HF severity and prognosis that may complement or even outperform traditional markers, such as N-terminal probrain natriuretic peptide. These findings lend support to a hypothesis implicating global systemic inflammation in HF with preserved ejection fraction.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov; Unique identifier: NCT00774709.

Household Fluorescent Lateral Flow Strip Platform for Sensitive and Quantitative Prognosis of Heart Failure Using Dual-Color Upconversion Nanoparticles

Heart failure (HF) is the end-stage of cardiovascular diseases, which is associated with a high mortality rate and high readmission rate. Household early diagnosis and real-time prognosis of HF at bedside are of significant importance. Here, we developed a highly sensitive and quantitative household prognosis platform (termed as UC-LFS platform), integrating a smartphone-based reader with multiplexed upconversion fluorescent lateral flow strip (LFS). Dual-color core-shell upconversion nanoparticles (UCNPs) were synthesized as probes for simultaneously quantifying two target antigens associated with HF, i.e., brain natriuretic peptide (BNP) and suppression of tumorigenicity 2 (ST2). With the fluorescent LFS, we achieved the specific detection of BNP and ST2 antigens in spiked samples with detection limits of 5 pg/mL and 1 ng/mL, respectively, both of which are of one order lower than their clinical cutoff. Subsequently, a smartphone-based portable reader and an analysis app were developed, which could rapidly quantify the result and share prognosis results with doctors. To confirm the usage of UC-LFS platform for clinical samples, we detected 38 clinical serum samples using the platform and successfully detected the minimal concentration of 29.92 ng/mL for ST2 and 17.46 pg/mL for BNP in these clinical samples. Comparing the detection results from FDA approved clinical methods, we obtained a good linear correlation, indicating the practical reliability and stability of our developed UC-LFS platform. Therefore, the developed UC-LFS platform is demonstrated to be highly sensitive and specific for sample-to-answer prognosis of HF, which holds great potential for risk assessment and health monitoring of post-treatment patients at home.

Mid-regional pro-adrenomedullin and ST2 in heart failure: Contributions to diagnosis and prognosis

Heart failure has a high prevalence in developed countries. It is a frequent cause of hospital admission and has an important impact on morbidity, mortality and healthcare costs. Biomarkers have been widely studied in heart failure, as they improve diagnosis and prognostic assessment. Natriuretic peptides are already a part of daily clinical practice but several other biomarkers are being studied. This review focuses on mid-regional pro-adrenomedullin (MR-proADM) and ST2. Neither of these biomarkers is useful in the diagnosis of acute heart failure. However, both have considerable short- and long-term prognostic value in patients with acute and with stable chronic heart failure. The utility of these two biomarkers in guiding heart failure treatment is yet to be established. ST2 appears to have some advantages compared to MR-proADM, because it is more closely associated with ventricular remodeling and fibrosis.

Predictors of Long-Term Mortality in Patients With Acute Heart Failure

To investigate parameters which were related with long-term mortality in patients hospitalized for acute heart failure (AHF).A total of 287 patients with AHF presenting to the First Affiliated Hospital of Nanjing Medical University were enrolled into the registry from April 2012 to January 2015. The primary endpoint was all-cause mortality within 1 year; the association between variables and prognosis was assessed after 1 year.Among the 287 patients, 17 did not continue follow-up and 47 (17.4%) passed away. Baseline NT-proBNP and sST2 concentrations were higher amongst deceased than among survivors (P < 0.001). Serum sodium concentrations of patients who died were lower (P < 0.001). In receiver operator characteristics (ROC) analyses, the area under the curve (AUC) values for NT-proBNP, sST2, and serum sodium to predict 1-year mortality were 0.699 (95%CI 0.639-0.755), 0.692, (95%CI 0.634-0.747), and 0.694 (95%CI 0.634-0.750), respectively. The optimal cut-off points for NT-proBNP, sST2, and serum sodium were 2137.0 ng/L, 35.711 ng/mL, and 136.6 mmol/L, respectively. In Cox regression analysis, ln-transformed NT-proBNP (HR 1.546, P = 0.039), ln-transformed sST2 (HR1.542, P = 0.049), and serum sodium (HR 0.880, P = 0.000) values reliably predicted long-term mortality after multivariable adjustment.In patients with acute heart failure, NT-proBNP, sST2 and serum sodium are potential predictors of 1-year mortality.

Low circulating microRNA levels in heart failure patients are associated with atherosclerotic disease and cardiovascular-related rehospitalizations

OBJECTIVE

Circulating microRNAs (miRNAs) have been implicated in both heart failure and atherosclerotic disease. The aim of this study was to examine associations between heart failure specific circulating miRNAs, atherosclerotic disease and cardiovascular-related outcome in patients with heart failure.

METHODS

The levels of 11 heart failure-specific circulating miRNAs were compared in plasma of 114 heart failure patients with and without different manifestations of atherosclerotic disease. We then studied these miRNAs in relation to biomarkers associated to atherosclerosis and to cardiovascular-related rehospitalizations during 18 months of follow-up.

RESULTS

At least one manifestation of atherosclerotic disease was found in 70 (61%) of the heart failure patients. A consistent trend was found between an increasing number of manifestations of atherosclerosis (peripheral arterial disease in specific), and lower levels of miR-18a-5p, miR-27a-3p, miR-199a-3p, miR-223-3p and miR-652-3p (all P < 0.05). Target prediction and network analyses identified several interactions between miRNA targets and biomarkers related to inflammation, angiogenesis and endothelial dysfunction. Lower miRNA levels were associated with higher levels of these atherosclerosis-related biomarkers. In addition, lower miRNA levels were significantly associated with rehospitalizations due to cardiovascular causes within 18 months, with let-7i-5p as strongest predictor [HR 2.06 (95% CI 1.29-3.28), C-index 0.70, P = 0.002].

CONCLUSIONS

A consistent pattern of lower levels of circulating miRNAs was found in heart failure patients with atherosclerotic disease, in particular peripheral arterial disease. In addition, lower levels of miRNAs were associated with higher levels of biomarkers involved in atherosclerosis and an increased risk of a cardiovascular-related rehospitalization.

Soluble ST2 predicts 1-year outcome in patients undergoing transcatheter aortic valve implantation

BACKGROUND

Soluble ST2 (sST2) has been introduced as a novel biomarker in patients suffering from heart failure for risk stratification. In this study, we sought to investigate whether sST2 is useful for risk stratification and prediction of mortality in patients undergoing transcatheter aortic valve implantation (TAVI).

MATERIALS AND METHODS

A total of 274 patients undergoing TAVI were included in this study (149 female; age 81 ± 1 years; EUROSCORE 25 ± 1; STS score 3·8 ± 0·2). Plasma samples were obtained preinterventional and analysed for sST2. Patients were followed up 1 month and 1 year after TAVI.

RESULTS

In a Cox regression analysis, sST2 plasma concentration was associated with increased mortality (changes per pg/mL sST2 concentration; HR 1·00006 95% (1·00004-1·00009); P < 0·001). A cut-off by means of the Youden Index was calculated (10 070·27 pg/mL), and patients were retrospectively divided into two cohorts, in those above (31·3%) and those below (68·7%) this value. These two groups were then compared regarding mortality both after 30 days and 1 year: whereas 1-month mortality did not differ (7·0% vs. 10·3%, OR 1·50 95% CI (0·60-3·79; P = 0·46)), patients with a sST2 concentration above the cut-off of 10 070·27 pg/mL showed a significantly worse outcome after 1 year (49·2% vs. 23·2%; OR 3·21 95% CI (1·70-6·04); P < 0·001). After correction for confounders in a multivariate Cox regression analysis, sST2 (1·0002 95% CI (1·0001-1·0003); P = 0·001) concentration remained associated with mortality.

CONCLUSIONS

sST2 levels were associated with 1-year mortality after TAVI. Based on these results, we assume that sST2 might help to identify patients at high risk for death in whom conservative treatment should be considered.

Natriuretic peptides as biomarkers of cardiac endocrine function in heart failure: new challenges and perspectives

Several studies indicated that B-type natriuretic peptide (BNP) assay is able to detect patients even in the early phases of heart failure (HF), when the myocardial remodeling process may be still reversible. BNP assay may assist the physician to initiate appropriate and prompt pharmacological treatments. However, clinical relevance and result interpretation of BNP assay for the guide of therapy or in particular clinical conditions, such as renal failure or treatment with inhibitors of enzymes degrading BNP in HF patients, are still debated. The aim of this article is to discuss some still controversial issues concerning the clinical use of measurement of cardiac natriuretic peptides, and also to provide a general overview and some perspectives related to pathophysiological mechanisms of HF.

Plasma Biomarkers Reflecting Profibrotic Processes in Heart Failure With a Preserved Ejection Fraction: Data From the Prospective Comparison of ARNI With ARB on Management of Heart Failure With Preserved Ejection Fraction Study

BACKGROUND

Heart failure with preserved ejection fraction is a clinical syndrome that has been associated with changes in the extracellular matrix. The purpose of this study was to determine whether profibrotic biomarkers accurately reflect the presence and severity of disease and underlying pathophysiology and modify response to therapy in patients with heart failure with preserved ejection fraction.

METHODS AND RESULTS

Four biomarkers, soluble form of ST2 (an interleukin-1 receptor family member), galectin-3, matrix metalloproteinase-2, and collagen III N-terminal propeptide were measured in the Prospective Comparison of ARNI With ARB on Management of Heart Failure With Preserved Ejection Fraction (PARAMOUNT) trial at baseline, 12 and 36 weeks after randomization to valsartan or LCZ696. We examined the relationship between baseline biomarkers, demographic and echocardiographic characteristics, change in primary (change in N-terminal pro B-type natriuretic peptide) and secondary (change in left atrial volume) end points. The median (interquartile range) value for soluble form of ST2 (33 [24.6-48.1] ng/mL) and galectin 3 (17.8 [14.1-22.8] ng/mL) were higher, and for matrix metalloproteinase-2 (188 [155.5-230.6] ng/mL) lower, than in previously published referent controls; collagen III N-terminal propeptide (5.6 [4.3-6.9] ng/mL) was similar to referent control values. All 4 biomarkers correlated with severity of disease as indicated by N-terminal pro B-type natriuretic peptide, E/E', and left atrial volume. Baseline biomarkers did not modify the response to LCZ696 for lowering N-terminal pro B-type natriuretic peptide; however, left atrial volume reduction varied by baseline level of soluble form of ST2 and galectin 3; patients with values less than the observed median (<33 ng/mL soluble form of ST2 and <17.8 ng/mL galectin 3) had reduction in left atrial volume, those above median did not. Although LCZ696 reduced N-terminal pro B-type natriuretic peptide, levels of the other 4 biomarkers were not affected over time.

CONCLUSIONS

In patients with heart failure with preserved ejection fraction, biomarkers that reflect collagen homeostasis correlated with the presence and severity of disease and underlying pathophysiology, and may modify the structural response to treatment.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00887588.

Biomarkers in heart failure with preserved ejection fraction

Biomarkers are widely used and studied in heart failure. Most studies have described the utility and performance of biomarkers in sub-studies of randomised clinical trials, where the vast majority of the patients suffered from heart failure with reduced ejection fraction (HFrEF), and not with preserved ejection fraction (HFpEF). As a result, there is a scarcity of data describing the levels, dynamics, clinical and biochemical correlates, and biology of biomarkers in patients suffering from HFpEF, whereas HFpEF is in fact a very frequent clinical entity. This article discusses the value of different biomarkers in HFpEF. We describe various aspects of natriuretic peptide measurements in HFpEF patients, with a focus on diagnosis, prognosis and the risk prediction of developing heart failure. Further, we will discuss several emerging biomarkers such as galectin-3 and suppression of tumorigenicity 2, and recently discovered ones such as growth differentiation factor-15 and syndecan-1.

Pattern of endothelial progenitor cells and apoptotic endothelial cell-derived microparticles in chronic heart failure patients with preserved and reduced left ventricular ejection fraction

BACKGROUND

Chronic heart failure (HF) remains a leading cause of cardiovascular (CV) mortality and morbidity worldwide. The aim of the study was to investigate whether the pattern of angiogenic endothelial progenitor cells (EPCs) and apoptotic endothelial cell-derived microparticles (EMPs) would be able to differentiate HF with reduced (HFrEF) and preserved (HFpEF) ejection fraction.

METHODS

One hundred sixty four chronic HF subjects met inclusion criteria. Patients with global left ventricular ejection fraction ≥ 50% were categorized as the HFpEF group (n = 79) and those with ≤ 45% as the HFrEF group (n = 85). Therefore, to compare the circulating levels of biological markers 35 control subjects without HF were included in the study. All control individuals were age- and sex-matched chronic HF patients. The serum level of biomarkers was measured at baseline. The flow cytometric technique was used for predictably distinguishing circulating cell subsets depending on expression of CD45, CD34, CD14, Tie-2, and CD309 antigens and determining endothelial cell-derived microparticles. CD31(+)/annexin V(+) was defined as apoptotic endothelial cell-derived MPs, MPs labeled for CD105(+) or CD62E(+) were determined as MPs produced due to activation of endothelial cells.

RESULTS

In multivariate logistic regression model T2DM (R(2) = 0.26; P = 0.001), obesity (R(2) = 0.22; P = 0.001), previous MI (R(2) = 0.17; P = 0.012), galectin-3 (R(2) = 0.67; P = 0.012), CD31(+)/annexin V(+) EMPs (R(2) = 0.11; P = 0.001), NT-proBNP (R(2) = 0.11; P = 0.046), CD14(+) CD309(+) cells (R(2) = 0.058; P = 0.001), and CD14(+) СD309(+) Tie-2(+) cells (R(2) = 0.044; P = 0.028) were found as independent predictors of HFpEF. Using multivariate Cox-regression analysis adjusted etiology (previous myocardial infarction), cardiovascular risk factors (obesity, type 2 diabetes mellitus) we found that NT-proBNP (OR 1.08; 95% CI = 1.03-1.12; P = 0.001) and CD31(+)/annexin V(+) EMPs to CD14(+) CD309(+) cell ratio (OR 1.06; 95% CI = 1.02-1.11; P = 0.02) were independent predictors for HFpEF.

CONCLUSION

We found that CD31(+)/annexin V(+) EMPs to CD14(+) CD309(+) cell ratio added to NT-proBNP, clinical data, and cardiovascular risk factors has exhibited the best discriminate value and higher reliability to predict HFpEF compared with NT-proBNP and clinical data/cardiovascular risk factors alone.

Galectin-3 and sST2 in prediction of left ventricular ejection fraction after myocardial infarction

BACKGROUND

Fibrosis is a pivotal event in infarct repair and progressive remodeling after myocardial infarction (MI). Biomarkers may be used to monitor fibrosis, and therefore we evaluated the predictive value of galectin-3 and sST2 for cardiac remodeling after MI.

METHODS

Plasma galectin-3 and sST2 were measured in patients admitted with primary percutaneous coronary intervention (PCI) for acute MI, at baseline and at 4months. Left ventricular ejection fraction (LVEF) and infarct size were measured after 4months with cardiac MRI (CMR).

RESULTS

In total, 247 patients had blood samples and CMR data available (mean age 57.7±11.6years; 79.8% male). Increased baseline galectin-3 (≥17.8ng/mL) identified patients with lower LVEF (50.3% (±9.1) vs. non-elevated galectin-3 55.0% (±8.0); P<0.001), and larger infarct size (13.8g. (±12.9) vs. 8.6g. (±8.7); P=0.002) after 4months. Elevated sST2 (≥35.0ng/mL) did not predict decreased LVEF or larger infarct size. Furthermore we showed that at baseline, galectin-3 was an independent predictor for LVEF (β=-0.18; P=0.005) and infarct size (β=0.18; P=0.004). We repeated the analyses using median values of galectin-3 (13.4ng/mL) and sST2 (30.3ng/mL) as a cut point, and this validated our results.

CONCLUSION

The fibrosis biomarker galectin-3, but not sST2, taken immediately after MI, predicts LVEF and infarct size after 4months. We hypothesize that galectin-3 may play a role in the pathophysiology of cardiac remodeling after acute MI.

Role of biomarkers in cardiac structure phenotyping in heart failure with preserved ejection fraction: critical appraisal and practical use

Heart failure (HF) with preserved ejection fraction (HFpEF) is a heterogeneous clinical syndrome characterized by cardiovascular, metabolic, and pro-inflammatory diseases associated with advanced age and extracardiac comorbidities. All of these conditions finally lead to impairment of myocardial structure and function. The large phenotypic heterogeneity of HFpEF from pathophysiological underpinnings presents a major hurdle to HFpEF therapy. The new therapeutic approach in HFpEF should be targeted to each HF phenotype, instead of the 'one-size-fits-all' approach, which has not been successful in clinical trials. Unless the structural and biological determinants of the failing heart are deeply understood, it will be impossible to appropriately differentiate HFpEF patients, identify subtle myocardial abnormalities, and finally reverse abnormal cardiac function. Based on evidence from endomyocardial biopsies, some of the specific cardiac structural phenotypes to be targeted in HFpEF may be represented by myocyte hypertrophy, interstitial fibrosis, myocardial inflammation associated with oxidative stress, and coronary disease. Once the diagnosis of HFpEF has been established, a potential approach could be to use a panel of biomarkers to identify the main cardiac structural HFpEF phenotypes, guiding towards more appropriate therapeutic strategies. Accordingly, the purpose of this review is to investigate the potential role of biomarkers in identifying different cardiac structural HFpEF phenotypes and to discuss the merits of a biomarker-guided strategy in HFpEF.

A combined clinical and biomarker approach to predict diuretic response in acute heart failure

Background

Poor diuretic response in acute heart failure is related to poor clinical outcome. The underlying mechanisms and pathophysiology behind diuretic resistance are incompletely understood. We evaluated a combined approach using clinical characteristics and biomarkers to predict diuretic response in acute heart failure (AHF).

Methods and results

We investigated explanatory and predictive models for diuretic response—weight loss at day 4 per 40 mg of furosemide—in 974 patients with AHF included in the PROTECT trial. Biomarkers, addressing multiple pathophysiological pathways, were determined at baseline and after 24 h. An explanatory baseline biomarker model of a poor diuretic response included low potassium, chloride, hemoglobin, myeloperoxidase, and high blood urea nitrogen, albumin, triglycerides, ST2 and neutrophil gelatinase-associated lipocalin (r² = 0.086). Diuretic response after 24 h (early diuretic response) was a strong predictor of diuretic response (β = 0.467, P < 0.001; r² = 0.523). Addition of diuretic response after 24 h to biomarkers and clinical characteristics significantly improved the predictive model (r² = 0.586, P < 0.001).

Conclusions

Biomarkers indicate that diuretic unresponsiveness is associated with an atherosclerotic profile with abnormal renal function and electrolytes. However, predicting diuretic response is difficult and biomarkers have limited additive value. Patients at risk of poor diuretic response can be identified by measuring early diuretic response after 24 h.

Electronic supplementary material

The online version of this article (doi:10.1007/s00392-015-0896-2) contains supplementary material, which is available to authorized users.