Cardiac biomarkers in heart failure

Assessing the diversity and determinants of health-related quality of life measures in patients with acute heart failure

AIMS

Heart failure with reduced ejection fraction (HFrEF) significantly impacts health-related quality of life (HR-QoL). Existing HR-QoL questionnaires can show inconsistencies, potentially misrepresenting patient self-reports. This study examines the variation in HR-QoL measurement tools for HFrEF patients, identifying related determinants.

METHODS AND RESULTS

We retrospectively analysed 134 hospitalized patients with acute decompensated HFrEF at a Taiwanese tertiary centre's Heart Failure Post-Acute-Care (HF-PAC) programme. Participants completed the EuroQol-5 dimension (EQ-5D) questionnaire, the EQ-5D visual analogue scale (VAS), and the Minnesota Living with Heart Failure Questionnaire (MLHFQ). Utility values were obtained from the EQ-5D questionnaire. Demographic features were depicted using descriptive statistics, while multivariate regression was used to ascertain relationships between HR-QoL measurements and determinants. Average scores for EQ-5D, MLHFQ, EQ-5D utility, and VAS were 6.1 ± 1.6, 21.8 ± 21.3, 81.7 ± 27.0, and 59.5 ± 14.6, respectively. Significant correlations were observed among the three tools. The New York Heart Association functional class showed a notable association with all tool scores. Other associations encompassed EQ-5D with coronary artery disease, mineralocorticoid receptor antagonists, and the 6 min walk test; EQ-5D VAS with chronic kidney disease; and MLHFQ with age.

CONCLUSIONS

This study illuminates the variance in HR-QoL measurement tools for Taiwanese HFrEF patients. Using a range of these tools is beneficial in unveiling diverse determinants and approaching comprehensive patient-centred care. However, for a more precise HR-QoL assessment in Taiwanese HFrEF patients, recalibrating the EQ-5D-derived utility scores might be necessary, emphasizing the importance of patient-specific considerations within the HF-PAC programme.

Neuromuscular disorders in the omics era

Neuromuscular disorders encompass a spectrum of conditions characterized by primary lesions within the peripheral nervous system, which include the anterior horn cell, peripheral nerve, neuromuscular junction, and muscle. In pediatrics, most of these disorders are linked to genetic causes. Despite the considerable progress, the diagnosis of these disorders remains a challenging due to wide clinical presentation, disease heterogeneity and rarity. It is noteworthy that certain neuromuscular disorders, once deemed untreatable, can now be effectively managed through novel therapies. Biomarkers emerge as indispensable tools, serving as objective measures that not only refine diagnostic accuracy but also provide guidance for therapeutic decision-making and the ongoing monitoring of long-term outcomes. Herein a comprehensive review of biomarkers in neuromuscular disorders is provided. We highlight the role of omics-based technologies that further characterize neuromuscular pathophysiology as well as identify potential therapeutic targets to guide treatment strategies.

Objective Methods of Assessing Fluid Status to Optimize Volume Management in Kidney Disease and Hypertension: The Importance of Ultrasound

Fluid overload, a prevalent complication in patients with renal disease and hypertension, significantly impacts patient morbidity and mortality. The daily clinical challenges that clinicians face include how to identify fluid overload early enough in the course of the disease to prevent adverse outcomes and to guide and potentially reduce the intensity of the diuresis. Traditional methods for evaluating fluid status, such as pitting edema, pulmonary crackles, or chest radiography primarily assess extracellular fluid and do not accurately reflect intravascular volume status or venous congestion. This review explores the rationale, mechanism, and evidence behind more recent methods used to assess volume status, namely, lung ultrasound, inferior vena cava (IVC) ultrasound, venous excess ultrasound score, and basic and advanced cardiac echocardiographic techniques. These methods offer a more accurate and objective assessment of fluid status, providing real-time, non-invasive measures of intravascular volume and venous congestion. The methods we discuss are primarily used in inpatient settings, but, given the increased pervasiveness of ultrasound technology, some could soon expand to the outpatient setting.

Cardioprotective Effect of Rheum turkestanicum Against Doxorubicin-Induced Toxicity in Rats

Background: Doxorubicin as an anti-cancer drug causes cardiotoxicity, limiting its tolerability and use. The mechanism of toxicity is due to free radical production and cardiomyocytes injury. This research evaluated Rheum turkestanicum (R.turkestanicum) extract against doxorubicin cardiotoxicity due to its considerable in vitro antioxidant activity. Methods: Male Wistar rats received 2.5 mg/kg doxorubicin intraperitoneally every other day for 2 weeks to create an accumulative dose. R. turkestanicum was administrated at a dose of 100 and 300 mg/kg intraperitoneally from the second week for 7 days. On the 15th day, the animals were anesthetized and blood was collected from cardiac tissue for evaluation of alanine aminotransferase (ALT), cardiac muscle creatinine kinase (CK-MB), troponin T (cTn-T), lactate dehydrogenase (LDH), and B-type natriuretic peptide brain natriuretic peptide. A cardiac homogenate was also collected to determine superoxide dismutase (SOD), catalase Catalase Activity, malondialdehyde (MDA), and thiols. Histopathology was also performed. Results: Doxorubicin increased all cardiac enzymes and malondialdehyde, correlating with a reduction in SOD, catalase, and thiols. Histopathology revealed extracellular edema, moderate congestion, and hemorrhage of foci. In contrast, administration of R. turkestanicum ameliorated these doxorubicin-induced pathophysiological changes. Conclusion: This study revealed that the extract ameliorated doxorubicin-induced cardiac toxicity via modulation of oxidative stress-related pathways. Liquid chromatography-mass spectrometry analysis of R. turkestanicum indicated several components with potent pharmacological properties.

Estimates of Prevalence of Pulmonary Hypertension according to Different International Definitions

Background

Pulmonary hypertension is a dreaded disease associated with considerable morbidity and mortality. The pulmonary hypertension developing due to chronic respiratory disease is a unique subset with symptoms often getting masqueraded by the underlying respiratory condition. The importance of early detection of this complication has been realized worldwide, and recently, the definition of pulmonary hypertension was revised to set the cutoff of mean pulmonary artery pressure (mPAP) at 20 mmHg instead of 25 mmHg at rest. In our study, we have tried to estimate the difference this new definition brings to the prevalence of pulmonary hypertension among interstitial lung disease patients at our centre.

Methods

This was a cross-sectional study in which all the patients of ILDs (n = 239) attending the outdoor and indoor Department of Respiratory Medicine, King George's Medical University, India, for the duration of one year were subjected to transthoracic echocardiography along with measurement of serum pro-B-type natriuretic peptide (BNP) and troponin T values. The data were analyzed using the different definitions, and the prevalence was compared.

Result

Incidence of pulmonary hypertension among ILD patients at mPAP cutoff ≥ 25 was 28.9%, while that at value ≥20 mmHg, incidence of pulmonary hypertension increased to 46.0%. An increment of 15-20% in incidence of pulmonary hypertension was observed among different types of ILD when cutoff of mPAP was changed.

Conclusion

The new definition helps in a significant increase in the detection of pulmonary hypertension, which certainly helps in earlier detection and better management of patients.

Protective effect of Vernonia amygdalina Delile against doxorubicin-induced cardiotoxicity

Doxorubicin has been used as an anticancer drug and has already indicated effective in the treatment of cancer. The incidence of cardiotoxicity due to doxorubicin was approximately 11%, resulting in the limited use of doxorubicin. Cardiac protection during doxorubicin therapy is needed because it can reduce the incidence of heart failure. Vernonia amygdalina (VA) is traditionally used by Indonesians as a traditional medicine and contains many secondary metabolites, including vernolide, vernodalol, vernoamygdalin, vernolepin, luteolin, luteolin 7-O-beta-glucoronoside and luteolin 7-O-glucoside. The pharmacological activity of VA has been widely studied, including its antimalarial, antidiabetic, anticancer, hepatoprotective, nephroprotective, and antioxidant activities. This research aimed to determine the antioxidant 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity, total phenol, total flavonoid, and cardioprotective effects of Vernonia Amygdalina. Negative control was only intraperitoneal injection of doxorubicin (20 mg/kgbw) on the eight day while quercetin (85 mg/kgbw) and ethanol extract of Vernonia amygdalina (EEVA) 100, 200, 400 mg/kgbw dose are orally administered for eight consecutive days. Both quercetin and EEVA groups were also injected with doxorubicin (20 mg/kgbw) on the same day. On the following day, rats were injected with ketamine HCL 75 mg/kgbw and were dissected for heart blood collected. The blood collected 3 ml from each rat was analyzed for biochemical parameters. The analyzed biochemical parameters were Aspartate transaminase (AST), Alanine transaminase (ALT), Ureum, Creatinine, Creatinine kinase-MB (CK-MB), Lactate dehydrogenase (LDH), Troponin T, Brain natriuretic peptide (BNP), and antioxidant parameter Superoxide Dismutase (SOD). The result showed that EEVA antioxidant activity was 40.51 ± 4.89 μg/mL, total flavonoid was 3.79 ± 0.61 mg QE/g extract, and total phenol was 281.575 ± 1.069 mg GAE/g extract. Quercetin (85 mg/kgbw) and EEVA (400 mg/kgbw) reduce AST, ALT, Ureum, Creatinine, CK- MB, LDH, Troponin T, BNP significantly and increase rats' SOD level compared with negative control. So that, this study explicates that EEVA potentials as cardioprotective agent against doxorubicin by reducing biochemical parameters.

Novel Biomarkers in Heart Failure: New Insight in Pathophysiology and Clinical Perspective

Heart failure (HF) is a complex clinical syndrome with a huge social burden in terms of cost, morbidity, and mortality. Brain natriuretic peptide (BNP) appears to be the gold standard in supporting the daily clinical management of patients with HF. Novel biomarkers may supplement BNP to improve the understanding of this complex disease process and, possibly, to personalize care for the different phenotypes, in order to ameliorate prognosis. In this review, we will examine some of the most promising novel biomarkers in HF. Inflammation plays a pivotal role in the genesis and progression of HF and, therefore, several candidate molecules have been investigated in recent years for diagnosis, prognosis, and therapy monitoring. Noncoding RNAs are attractive as biomarkers and their potential clinical applications may be feasible in the era of personalized medicine. Given the complex pathophysiology of HF, it is reasonable to expect that the future of biomarkers lies in the application of precision medicine, through wider testing panels and “omics” technologies, to further improve HF care delivery.

Immune Mechanisms in Cardiovascular Diseases Associated With Viral Infection

Influenza virus infection causes 3-5 million cases of severe illness and 250,000-500,000 deaths worldwide annually. Although pneumonia is the most common complication associated with influenza, there are several reports demonstrating increased risk for cardiovascular diseases. Several clinical case reports, as well as both prospective and retrospective studies, have shown that influenza can trigger cardiovascular events including myocardial infarction (MI), myocarditis, ventricular arrhythmia, and heart failure. A recent study has demonstrated that influenza-infected patients are at highest risk of having MI during the first seven days of diagnosis. Influenza virus infection induces a variety of pro-inflammatory cytokines and chemokines and recruitment of immune cells as part of the host immune response. Understanding the cellular and molecular mechanisms involved in influenza-associated cardiovascular diseases will help to improve treatment plans. This review discusses the direct and indirect effects of influenza virus infection on triggering cardiovascular events. Further, we discussed the similarities and differences in epidemiological and pathogenic mechanisms involved in cardiovascular events associated with coronavirus disease 2019 (COVID-19) compared to influenza infection.

Association of the Novel Inflammatory Marker GlycA and Incident Heart Failure and Its Subtypes of Preserved and Reduced Ejection Fraction: The Multi-Ethnic Study of Atherosclerosis

BACKGROUND

GlycA, a nuclear magnetic resonance composite marker of systemic inflammation, reflects serum concentration and glycosylation state of main acute phase reactants. Prior studies have shown plasma GlycA levels were associated with cardiovascular disease even after adjusting for other inflammatory markers. However, little is known about the association of GlycA with the heart failure (HF) subtypes: heart failure with preserved ejection fraction (HFpEF) or heart failure with reduced ejection fraction. We examined the association of GlycA with incident HF and its subtypes in a multiethnic cohort.

METHODS

We studied 6507 Multi-Ethnic Study of Atherosclerosis participants aged 45 to 84 without baseline cardiovascular disease or HF who had data on GlycA and incident hospitalized HF. We used multivariable-adjusted Cox hazards models to evaluate the association of GlycA with incident total HF, HFpEF, and heart failure with reduced ejection fraction. Models were adjusted for sociodemographics, cardiovascular disease risk factors, and inflammatory biomarkers.

RESULTS

The mean (SD) for age was 62 (10) years and for GlycA was 375 (82) μmol/L; 53% women. Over a median follow-up of 14.0 years, participants in the highest quartile of GlycA, compared with the lowest, experienced increased risk of developing any HF (hazard ratio, 1.48 [95% CI, 1.01-2.18]) in fully adjusted models. However, this increased risk was only seen for HFpEF (2.18 [1.15-4.13]) and not heart failure with reduced ejection fraction [1.06 (0.63-1.79)]. There was no significant interaction by sex, age, or race/ethnicity.

CONCLUSIONS

GlycA was associated with an increased risk of any HF, and in particular, HFpEF. Future studies should examine mechanisms that might explain differential association of GlycA with HF subtypes, and whether therapeutic lowering of GlycA can prevent HFpEF development. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT00005487.

Canine Traditional Laboratory Tests and Cardiac Biomarkers

In small animals, cardiac disease evaluation through laboratory tests can be a challenge. This review will present both historical and updated perspectives on the clinical pathology of cardiac diseases in dogs and demonstrate that laboratory tests are useful tools for the management of patients with cardiac diseases.

Biomarkers in heart failure: the past, current and future

Despite the enhanced knowledge of the pathophysiology of heart failure (HF), it still remains a serious syndrome with substantial morbidity, mortality, and frequent hospitalizations. These are due to the current improvements in other cardiovascular diseases (like myocardial infarction), the aging population, and growing prevalence of comorbidities. Biomarker-guided management has brought a new dimension in prognostication, diagnosis, and therapy options. Following the recommendation of natriuretic peptides (B-type natriuretic peptide and N-terminal-proBNP), many other biomarkers have been thoroughly studied to reflect different pathophysiological processes (such as fibrosis, inflammation, myocardial injury, and remodeling) in HF and some of them (like cardiac troponins, soluble suppression of tumorigenesis-2, and galectin 3) have subsequently been recommended to aid in the diagnosis and prognostication in HF. Consequently, multi-marker approach has also been approved owing to the varied nature of HF syndrome. In this review, we discussed the guidelines available for HF biomarkers, procedures for evaluating novel markers, and the utilities of both emerging and established biomarkers for risk stratification, diagnosis, and management of HF in the clinics. We later looked at how the rapidly emerging field-OMICs, can help transform HF biomarkers discoveries and establishment.

Usefulness of Biomarkers for Predicting Response to Cardiac Resynchronization Therapy

Cardiac Resynchronization Therapy (CRT) is an effective treatment strategy for heart failure. It significantly improves clinical symptoms and decreases mortality and long-term morbidity. However, some patients do not respond properly to this treatment. In this review, the role of different biomarkers in predicting response to CRT is discussed. Some biomarkers, including natriuretic peptides and inflammatory markers have promising results but further trials are needed for more evaluation.

Towards Point-of-Care Heart Failure Diagnostic Platforms: BNP and NT-proBNP Biosensors

Heart failure is a class of cardiovascular diseases that remains the number one cause of death worldwide with a substantial economic burden of around $18 billion incurred by the healthcare sector in 2017 due to heart failure hospitalization and disease management. Although several laboratory tests have been used for early detection of heart failure, these traditional diagnostic methods still fail to effectively guide clinical decisions, prognosis, and therapy in a timely and cost-effective manner. Recent advances in the design and development of biosensors coupled with the discovery of new clinically relevant cardiac biomarkers are paving the way for breakthroughs in heart failure management. Natriuretic neurohormone peptides, B-type natriuretic peptide (BNP) and N-terminal prohormone of BNP (NT-proBNP), are among the most promising biomarkers for clinical use. Remarkably, they result in an increased diagnostic accuracy of around 80% owing to the strong correlation between their circulating concentrations and different heart failure events. The latter has encouraged research towards developing and optimizing BNP biosensors for rapid and highly sensitive detection in the scope of point-of-care testing. This review sheds light on the advances in BNP and NT-proBNP sensing technologies for point-of-care (POC) applications and highlights the challenges of potential integration of these technologies in the clinic. Optical and electrochemical immunosensors are currently used for BNP sensing. The performance metrics of these biosensors-expressed in terms of sensitivity, selectivity, reproducibility, and other criteria-are compared to those of traditional diagnostic techniques, and the clinical applicability of these biosensors is assessed for their potential integration in point-of-care diagnostic platforms.

An update on the use and discovery of prognostic biomarkers in acute decompensated heart failure

Introduction: Acute decompensated heart failure (ADHF) remains a significant health care burden as evidenced by high readmission rates and mortality. Over the years, the care of patients with ADHF has been transformed by the use of biomarkers, specifically to aid in the diagnosis and prognosis. Patients with HF follow a variable course given the complex and heterogenous pathophysiological processes, thus it is imperative for clinicians to have tools to predict short and long-term outcomes in order to educate patients and optimize management. Areas Covered: The natriuretic peptides, including B-type natriuretic peptide and N-terminal pro-B-type natriuretic peptide, are considered the gold standard biomarkers. Yet, other emerging biomarkers such as suppression of tumerogenicity-2, cardiac troponin, galectin-2, mid-regional pro-adrenomedullin, copeptin, cystatin, and neutrophil gelatinase-associated lipocalin have increasingly shown promise in evaluating prognosis in patients with ADHF. This article reviews the pathophysiology and utility of both established and emerging biomarkers for the prognostication of patients with ADHF. Expert Opinion: As of 2019, the most validated biomarkers for use in decompensated heart failure include natriuretic peptides, high sensitivity troponin, and sST2. These biomarkers are involved in the underlying pathophysiology of disease and as such provide added information to that of exam, x-ray, and echocardiography.

Placenta growth factor and sFlt-1 as biomarkers in ischemic heart disease and heart failure: a review

Coronary heart disease (CHD) and heart failure (HF) produce significant morbidity/mortality but identifying new biomarkers could help in the management of each. In this article, we summarize the molecular regulation and biomarker potential of PIGF and sFlt-1 in CHD and HF. PlGF is elevated during ischemia and some studies have shown PlGF, sFlt-1 or PlGF:sFlt-1 ratio, when used in combination with standard biomarkers, strengthens predictions of outcomes. sFlt-1 and PlGF are elevated in HF with sFlt-1 as a stronger predictor of outcomes. Although promising, we discuss additional study criteria needed to confirm the clinical usefulness of PlGF or sFlt-1 in the detection and management of CHD or HF.

Glucotoxicity results in apoptosis in H9c2 cells via alteration in redox homeostasis linked mitochondrial dynamics and polyol pathway and possible reversal with cinnamic acid

Several mechanisms have been proposed for the heart dysfunction during hyperglycemia. The aim of the present in vitro study is to elucidate the role of alterations in redox homeostasis in the induction of apoptosis during hyperglycemia in H9c2 cells via dysfunction in mitochondria and polyol pathway and evaluation of the beneficial effect of cinnamic acid against the same. The H9c2 cells were incubated with 33 mM glucose for 48 h to simulate the diabetic condition. Cell injury was confirmed with a significant increase of atrial natriuretic peptide and lactate dehydrogenase release. Alterations in the innate antioxidant system, polyol pathway, mitochondrial integrity, dynamics and apoptosis were investigated. Hyperglycemic insult has significantly affected redox homeostasis via depletion of superoxide dismutase, glutathione and enhanced reactive oxygen species generation. It also caused dysregulation in mitochondrial dynamics (fusion, fission proteins), dissipation of mitochondrial transmembrane potential and increased sorbitol accumulation. Finally, apoptosis was observed with upregulation of Bax, activation of caspase-3 and downregulation of Bcl-2. Cinnamic acid cotreatment increased the innate antioxidant status, improved mitochondrial function and prevented apoptosis in H9c2 cardiomyoblasts. Moreover, this in vitro model is found to be ideal for the elucidation of mechanisms at the cellular and molecular level of any physiological, pharmacological and toxicological incidents in H9c2 cells.

Differential protein profiling as a potential multi-marker approach for obese patients with heart failure: A retrospective study

Identification of novel circulating biomarkers predicting death and major cardio-metabolic events in obese patients with heart failure (HF) remains a research priority. In this study, we compared multi-marker profile of non-obese (NOB) and obese (OB) HF patients in relation to mortality outcome. The new multiplex proximity extension assay technology was used to analyze the levels of 92 proteins in plasma samples from HF patients according to body mass index (BMI) categories. At 2-year follow-up, all-cause mortality rates were significantly greater in NOB patients (BMI < 30 kg/m²) compared to the OB patients (BMI > 30 kg/m²) with HF (odds ratio 26; 95% CI: 1.14–624, p < 0,04). Quantitative proteomic analysis revealed thirteen distinct proteins expression profiles of OB and NOB HF patients. Among these proteins, RAGE, CXCL6, CXCL1, CD40, NEMO, VEGF-A, KLK6, PECAM1, PAR1, MMP1, BNP and NTproBNP were down-regulated, whereas leptin was up-regulated in OB HF patients. In addition, an inverse correlation between plasma BNP levels and leptin in OB HF patients was observed (r = −0.58 p = 0.02). This study identifies specific plasma protein signature in OB and NOB patients with HF in relation to mortality outcome.

Novel heart failure biomarkers: why do we fail to exploit their potential?

Plasma biomarkers are useful tools in the diagnosis and prognosis of heart failure (HF). In the last decade, numerous studies have aimed to identify novel HF biomarkers that would provide superior and/or additional diagnostic, prognostic, or stratification utility. Although numerous biomarkers have been identified, their implementation in clinical practice has so far remained largely unsuccessful. Whereas cardiac-specific biomarkers, including natriuretic peptides (ANP and BNP) and high sensitivity troponins (hsTn), are widely used in clinical practice, other biomarkers have not yet proven their utility. Galectin-3 (Gal-3) and soluble suppression of tumorigenicity 2 (sST2) are the only novel HF biomarkers that are included in the ACC/AHA HF guidelines, but their clinical utility still needs to be demonstrated. In this review, we will describe natriuretic peptides, hsTn, and novel HF biomarkers, including Gal-3, sST2, human epididymis protein 4 (HE4), insulin-like growth factor-binding protein 7 (IGFBP-7), heart fatty acid-binding protein (H-FABP), soluble CD146 (sCD146), interleukin-6 (IL-6), growth differentiation factor 15 (GDF-15), procalcitonin (PCT), adrenomedullin (ADM), microRNAs (miRNAs), and metabolites like 5-oxoproline. We will discuss the biology of these HF biomarkers and conclude that most of them are markers of general pathological processes like fibrosis, cell death, and inflammation, and are not cardiac- or HF-specific. These characteristics explain to a large degree why it has been difficult to relate these biomarkers to a single disease. We propose that, in addition to clinical investigations, it will be pivotal to perform comprehensive preclinical biomarker investigations in animal models of HF in order to fully reveal the potential of these novel HF biomarkers.

A novel label-free photoelectrochemical immunosensor based on NCQDs and Bi2S3 co-sensitized hierarchical mesoporous SnO2 microflowers for detection of NT-proBNP

A novel label-free PEC immunosensor based on NCQDs and Bi₂S₃ co-sensitized hierarchical mesoporous SnO₂ microflowers was developed for NT-proBNP detection.

Sandwich-Type Electrochemiluminescence Sensor for Detection of NT-proBNP by Using High Efficiency Quench Strategy of Fe3O4@PDA toward Ru(bpy)32+ Coordinated with Silver Oxalate

Heart failure (HF) is a burgeoning public health problem trigged by a heart circulation disorder. N-terminal pro-B-type natriuretic peptide (NT-proBNP) has been acknowledged as a prognostic biomarker for cardiac disease. Herein, a sandwich-type electrochemiluminescence (ECL) immunosensor was introduced for sensitive detection of NT-proBNP. Gold nanoparticle modified graphene oxide-Ru(bpy)₃²⁺/Ag₂C₂O₄ was used as a luminophore and a desirable platform for immobilization of the captured antibodies. The more stable immobilization of plentiful Ru(bpy)₃²⁺ could be implemented by direct covalent bonding chelation with Ag₂C₂O₄. More importantly, significant quenching can be achieved by introducing polydopamine (PDA) coated Fe₃O₄ onto the electrode via sandwich immunoreactions. The quenching mechanism mainly showed that the excited states of Ru(bpy)₃²⁺ could be annihilated by quinone units in PDA via energy transfer. The ECL quenching efficiency was logarithmically related to the concentration of the NT-proBNP in the range from 0.0005 ng/mL to 100.0 ng/mL with a detection limit of 0.28 pg/mL. Furthermore, this specific immunosensor presented good stability and repeatability as well as selectivity, which offers a guiding significance in both fundamental and clinical diagnosis of NT-proBNP.

Cardiac troponins: from myocardial infarction to chronic disease

Elucidation of the physiologically distinct subunits of troponin in 1973 greatly facilitated our understanding of cardiac contraction. Although troponins are expressed in both skeletal and cardiac muscle, there are isoforms of troponin I/T expressed selectively in the heart. By exploiting cardiac-restricted epitopes within these proteins, one of the most successful diagnostic tests to date has been developed: cardiac troponin (cTn) assays. For the past decade, cTn has been regarded as the gold-standard marker for acute myocardial necrosis: the pathological hallmark of acute myocardial infarction (AMI). Whilst cTn is the cornerstone for ruling-out AMI in patients presenting with a suspected acute coronary syndrome (ACS), elevated cTn is frequently observed in those without clinical signs indicative of AMI, often reflecting myocardial injury of 'unknown origin'. cTn is commonly elevated in acute non-ACS conditions, as well as in chronic diseases. It is unclear why these elevations occur; yet they cannot be ignored as cTn levels in chronically unwell patients are directly correlated to prognosis. Paradoxically, improvements in assay sensitivity have meant more differential diagnoses have to be considered due to decreased specificity, since cTn is now more easily detected in these non-ACS conditions. It is important to be aware cTn is highly specific for myocardial injury, which could be attributable to a myriad of underlying causes, emphasizing the notion that cTn is an organ-specific, not disease-specific biomarker. Furthermore, the ability to detect increased cTn using high-sensitivity assays following extreme exercise is disconcerting. It has been suggested troponin release can occur without cardiomyocyte necrosis, contradicting conventional dogma, emphasizing a need to understand the mechanisms of such release. This review discusses basic troponin biology, the physiology behind its detection in serum, its use in the diagnosis of AMI, and some key concepts and experimental evidence as to why cTn can be elevated in chronic diseases.

Interleukin 1 Receptor-Like 1 Protein (ST2) is a Potential Biomarker for Cardiomyopathy in Duchenne Muscular Dystrophy

Duchenne muscular dystrophy (DMD) is a rare, fatal X-linked disorder characterized by the lack of dystrophin, a key sarcolemma muscle protein. Cardiac failure is a significant cause of death in DMD subjects. The purpose of our research was to identify potential cardiac serum biomarkers associated with DMD cardiomyopathy. This is an observational, case-controlled study using subjects from the CINRG DMD natural history study with cardiomyopathy (ejection fraction (EF) <55%; shortening fraction (SF) <28%), subjects without cardiomyopathy (EF ≥ 55%; SF ≥ 28%) compared to normal healthy volunteer subjects. The DMD with cardiomyopathy group had significantly lower average EF and SF (EF = 45 ± 10/SF = 25 ± 2%) than the DMD without cardiomyopathy group (EF = 58 ± 5% and SF = 32 ± 3%; p < 0.01). Among a selected set of potential biomarkers for cardiomyopathy (MMP9, BNP, GAL3, CRP, LEP, TNC, TLR4 and ST2) we validated ST2 as significantly elevated in the serum of DMD cardiomyopathy group (35,798 ± 4884 pg/mL) compared to normal controls (9940 ± 2680 pg/mL; p < 0.01; n = 6). Matrix metallopeptidase 9 (MMP9) levels were found significantly increased in both DMD groups compared to controls (p < 0.01). No significant differences were seen in BNP, GAL3, CRP, LEP, TNC or TLR4 levels. Increased ST2 levels were found in serum of DMD subjects compared to healthy volunteers and further elevated in DMD subjects with cardiomyopathy. Future studies correlating cardiomyopathy with ST2 levels may allow for improved non-invasive monitoring of cardiac disease in DMD subjects.

Natriuretic Peptides as Biomarkers for Congestive States: The Cardiorenal Divergence

Congestion represents the primary reason for hospitalization of patients with heart failure and is associated with adverse outcomes. Fluid overload has been shown to be inadequately addressed in a significant subset of these patients in part due to lack of robust, reliable, and readily available biomarkers for objective assessment and monitoring of therapy. Natriuretic peptides have long been used in this setting, often in conjunction with other assessment tools such as imaging studies. Patients presenting with concomitant cardiac and renal dysfunction represent a unique population with regard to congestion in that the interactions between the heart and the kidney can affect the utility and performance of biomarkers of fluid overload. Herein, we provide an overview of the currently available evidence on the utility of natriuretic peptides in these patients and discuss the clinical conundrum associated with their use in the setting of renal dysfunction. We highlight the potential divergence in the role of natriuretic peptides for assessment of volume status in a subset of patients with renal dysfunction who receive renal replacement therapy and call for future research to elucidate the utility of the biomarkers in this setting.

Cardioprotection against Heart Failure by Shenfu Injection via TGF-β/Smads Signaling Pathway

Objective

To explore the potential cardioprotective mechanism of Shenfu injection (SFI) against heart failure (HF) by attenuating myocardial fibrosis and cardiac remodeling.

Methods and Results

Four weeks after myocardial infarction (MI), adult male Sprague Dawley rats were randomized for 4-week treatment with Valsartan, SFI, or vehicle. Echocardiography and hemodynamics were applied to evaluate cardiac functions. Myocardia of coronary artery ligated (CAD) rats were observed to investigate changes in cardiac structure and function. Our findings suggest that treatment with SFI could inhibit progression of myocardial fibrosis and attenuate cardiac remodeling. In addition, SFI decreased expression of Smad2 and Smad3, while increasing the expression of Smad7 through regulation of TGF-β/Smads signaling pathway.

Conclusion

Treatment with SFI in Sprague Dawley rats improves ventricular structure and function and reduces cardiac fibrosis by ameliorating TGF-β/Smads signaling pathway after ventricular remodeling.

Lipophilic Statin Versus Rosuvastatin (Hydrophilic) Treatment for Heart Failure: a Meta-Analysis and Adjusted Indirect Comparison of Randomised Trials

OBJECTIVES

This study aims to compare lipophilic and hydrophilic statin therapy on clinical outcomes of heart failure (HF) using a systematic review and an adjusted indirect comparison meta-analysis. Outcomes were all-cause mortality, cardiovascular mortality, cardiovascular hospitalization and hospitalization for worsening HF.

METHODS

We conducted a search of PubMed, EMBASE and Cochrane databases until 31st December 2014 for randomized control trials (RCTs) in HF evaluating statins versus placebo. Identified RCTs and their respective abstracted information were grouped according to statin type evaluated and analyzed separately. Outcomes were initially pooled with the Peto's one-step method, producing odd ratios (OR) and 95 % confidence intervals (CI) for each statin type. Using these pooled estimates, we performed adjusted indirect comparisons of lipophilic versus hydrophilic statin for each outcome.

RESULTS

Thirteen studies involving 10,966 patients were identified and analyzed. Lipophilic statins were superior to hydrophilic rosuvastatin regarding all-cause mortality (OR 0 · 50; 95 % CI, 0 · 11-0 · 89; p = 0 · 01), cardiovascular mortality (OR 0 · 61; 0 · 25-0 · 97; p = 0 · 009), and hospitalization for worsening HF (OR 0 · 52; 0 · 21-0 · 83; p = 0 · 0005). However, both statins were comparable with regards to cardiovascular hospitalization [OR 0 · 80 (0 · 31, 1 · 28); p = 0 · 36].

CONCLUSIONS

Lipophilic statin treatment shows significant decreases in all-cause mortality, cardiovascular mortality and hospitalization for worsening HF compared with rosuvastatin treatment. This meta-analysis provides preliminary evidence that lipophilic statins offer better clinical outcomes in HF till data from head to head comparisons are available.

Circulating biomarker responses to medical management vs. mechanical circulatory support in severe inotrope-dependent acute heart failure

Background

Severe inotrope‐dependent acute heart failure (AHF) is associated with poor clinical outcomes. There are currently no well‐defined blood biomarkers of response to treatment that can guide management or identify recovery in this patient population. In the present study, we characterized the levels of novel and emerging circulating biomarkers of heart failure in patients with AHF over the first 30 days of medical management or mechanical circulatory support (MCS). We hypothesized a shared a plasma proteomic treatment response would be identifiable in both patient groups, representing reversal of the AHF phenotype.

Methods and results

Time course plasma samples of the first 30 days of therapy, obtained from patients managed medically (n = 8) or with implantable MCS (n = 5), underwent semi‐targeted and candidate biomarker analyses, using multiple reaction monitoring (MRM) mass spectrometry, antibody arrays, and enzyme‐linked immunosorbent assays. Differentially expressed proteins were identified using robust limma for MRM and antibody array data. Patients managed medically or with implantable MCS had a shared proteomic signature of six plasma proteins: circulating cardiotrophin 1, cardiac troponin T, clusterin, and dickopff 1 increased, while levels of C‐reactive protein and growth differentiation factor 15 decreased in both groups over the 30 day time course.

Conclusions

We have characterized the temporal proteomic signature of clinical recovery in AHF patients managed medically or with MCS, over the first 30 days of treatment. Changes in biomarker expression over the time course of treatment may provide a basis for understanding the biological basis of AHF, potentially identifying novel markers and pathophysiologic mechanisms of recovery.

Enhanced monocyte chemoattractant protein-1 production in aging mice exaggerates cardiac depression during endotoxemia

Introduction

Endotoxemia and the systemic inflammatory response syndrome have a significant impact on post-surgery outcome, particularly in the elderly. The cytokine response to endotoxin is altered by aging. We tested the hypothesis that vulnerability to endotoxemic cardiac depression increases with aging due to age-related augmentation of myocardial inflammatory responses.

Methods

Adult (4 to 6 months) and old (20 to 22 months) C57/BL6 mice were treated with endotoxin (0.5 mg/kg, iv). Left ventricle (LV) function was assessed using a microcatheter system. Chemokines and cytokines in plasma and myocardium were analyzed by enzyme-linked immunosorbent assay (ELISA). Mononuclear cells in the myocardium were examined using immunofluorescence staining.

Results

Old mice displayed worse LV function (cardiac output: 3.0 ± 0.2 mL/min versus 4.4 ± 0.3 mL/min in adult mice) following endotoxin treatment. The exaggerated cardiac depression in old mice was associated with higher levels of monocyte chemoattractant protein-1 (MCP-1) and keratinocyte chemoattractant (KC) in plasma and myocardium, greater myocardial accumulation of mononuclear cells, and greater levels of tumor necrosis factor-α (TNF-α), interleukin 1β (IL-1β) and interleukin 6 (IL-6) in plasma and myocardium. Neutralization of MCP-1 resulted in greater reductions in myocardial mononuclear cell accumulation and cytokine production, and greater improvement in LV function in old mice while neutralization of KC had a minimal effect on LV function.

Conclusion

Old mice have enhanced inflammatory responses to endotoxemia that lead to exaggerated cardiac functional depression. MCP-1 promotes myocardial mononuclear cell accumulation and cardiodepressant cytokines production, and plays an important role in the endotoxemic cardiomyopathy in old mice. The findings suggest that special attention is needed to protect the heart in the elderly with endotoxemia.