B-type natriuretic peptide as a biomarker beyond heart failure: speculations and opportunities

Biomarkers to Improve Decision-making in Acute Heart Failure

Acute heart failure (AHF) is a complex clinical syndrome that requires prompt diagnosis, risk stratification and effective treatment strategies to reduce morbidity and mortality. Biomarkers are playing an increasingly important role in this process, offering valuable insights into the underlying pathophysiology and facilitating personalised patient management. This review summarises the significance of various biomarkers in the context of AHF, with a focus on their clinical applications to stratify risk and potential for guiding therapy choices.

Association of B-Type Natriuretic Peptide Level with Clinical Outcome in Out-of-Hospital Cardiac Arrest in Emergency Department Patients

OBJECTIVES

B-type natriuretic peptide (BNP) is used for outcome assessment of various diseases. We designed this study to investigate whether BNP, which has been proven useful in the risk stratification of sudden cardiac arrest (SCA) of cardiac etiology, can also prove to be a valuable prognostic tool for SCA also included with non-cardiac etiology. In this study, we aim to investigate the relationship between measured BNP levels and clinical outcomes in SCA, regardless of the cause of SCA.

METHODS

This retrospective multicenter observational study was performed in two tertiary university hospitals and one general hospital between January 2015 and December 2020. The total number of SCA patients was 1625. The patients with out-of-hospital cardiac arrest over 19 years old and acquired laboratory data, including BNP at emergency department (ED) arrival, were included. BNP was measured during advanced Cardiovascular Life Support (ACLS). The exclusion criteria were age under 18 years, traumatic arrest, and without BNP.

RESULTS

The median BNP was 171.8 (range; 5-5000) pg/mL in the return of Spontaneous Circulation (ROSC), higher than No-ROSC (p = 0.007). The median BNP concentration was 99.7 (range; 5-3040.68) pg/mL in the survival to discharge, which was significantly lower than the death group (p = 0.012). The odds ratio of survival to discharge decreased proportionally to the BNP level. The odds ratio of neurologic outcome was not correlated with the BNP level.

CONCLUSION

In patients with SCA of all origins, low BNP concentration measured during ACLS correlated with an increased ratio of survival to discharge. However, BNP measured during ACLS was not found to be an independent factor.

Electrocardiographic, hemodynamic, and biochemical evidence on the protective effects of exenatide against phosphine-induced cardiotoxicity in rat model

Aluminum phosphide (AlP) poisoning can be deadly in most cases targeting the heart. To overcome AlP toxicity, exenatide has been studied in the present study due to its pleiotropic effects on cardiac damages. In this study, the rats were exposed to LD₅₀ of AlP (10 mg/kg) by gavage, and exenatide at doses (0.05, 0.1, and 0.2 mg/kg) injected intraperitoneally 30 min after poisoning. The cardiac parameters including heart rate (HR), blood pressure (BP), QRS, corrected QT (QT_c), and ST were monitored for 180 min. Blood glucose level was measured in the study groups 30 min after exenatide injection. Evaluation of biochemical parameters including mitochondrial complexes I, II, and IV activities, adenosine diphosphate (ADP)/adenosine triphosphate (ATP) ratio, malondialdehyde (MDA), apoptosis, lactate, troponin I, and brain natriuretic peptide (BNP) was done on heart tissues after 12 and 24 h. Additionally, the tissues were analyzed for any pathological damages including necrosis, hemorrhage, or hyperemia 24 h post-treatment. Our results showed that AlP-induced HR, BP, and electrocardiographic changes were improved by exenatide at all doses. The blood glucose levels of poisoned animals reached control levels after exenatide treatment. Besides, treatment with exenatide at all doses improved complexes I and IV activity, ADP/ATP ratio, and apoptosis. Malondialdehyde, lactate, troponin I, and BNP levels were also diminished after exenatide co-treatment in poisoned animals. On the other hand, administration of exenatide doses improved the histopathology of AlP-induced tissues. Based on our findings, exenatide has a protective effect against phosphine-induced cardiotoxicity in an almost dose-dependent way. However, further investigations are needed on the potential clinical use of exenatide in this poisoning.

A three-tiered integrative analysis of transcriptional data reveals the shared pathways related to heart failure from different aetiologies

Heart failure (HF) is the end stage of most heart disease cases and can be initiated from multiple aetiologies. However, whether the molecular basis of HF has a commonality between different aetiologies has not been elucidated. To address this lack, we performed a three‐tiered analysis by integrating transcriptional data and pathway information to explore the commonalities of HF from different aetiologies. First, through differential expression analysis, we obtained 111 genes that were frequently differentially expressed in HF from 11 different aetiologies. Several genes, such as NPPA and NPPB, are early and accurate biomarkers for HF. We also provided candidates for further experimental verification, such as SERPINA3 and STAT4. Then, using gene set enrichment analysis, we successfully identified 19 frequently dysregulated pathways. In particular, we found that pathways related to immune system signalling, the extracellular matrix and metabolism were critical in the development of HF. Finally, we successfully acquired 241 regulatory relationships between 64 transcriptional factors (TFs) and 17 frequently dysregulated pathways by integrating a regulatory network, and some of the identified TFs have already been proven to play important roles in HF. Taken together, the three‐tiered analysis of HF provided a systems biology perspective on HF and emphasized the molecular commonality of HF from different aetiologies.

Circular RNA Expression Profiles in Plasma from Patients with Heart Failure Related to Platelet Activity

Heart failure (HF) is a deadly disease that is difficult to accurately diagnose. Circular RNAs (circRNAs) are a novel class of noncoding RNAs that might play important roles in many cardiovascular diseases. However, their role in HF remains unclear. CircRNA microarrays were performed on plasma samples obtained from three patients with HF and three healthy controls. The profiling results were validated by quantitative reverse transcription polymerase chain reaction. The diagnostic value of circRNAs for HF was evaluated by receiver operating characteristic (ROC) curves. The expression profiles indicated that 477 circRNAs were upregulated and 219 were downregulated in the plasma of patients with HF compared with healthy controls. Among the dysregulated circRNAs, hsa_circ_0112085 (p = 0.0032), hsa_circ_0062960 (p = 0.0006), hsa_circ_0053919 (p = 0.0074) and hsa_circ_0014010 (p = 0.025) showed significantly higher expression in patients with HF compared with healthy controls. The area under the ROC curve for hsa_circ_0062960 for HF diagnosis was 0.838 (p < 0.0001). Correlation analysis showed that the expression of hsa_circ_0062960 was highly correlated with B-type natriuretic peptide (BNP) serum levels. Some differential circRNAs were found to be related to platelet activity by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. The landscape of circRNA expression profiles may play a role in HF pathogenesis and improve our understanding of platelet function in HF. Moreover, hsa_circ_0062960 has potential as a novel diagnostic biomarker for HF.

Left Ventricular Deformation in Patients with Connective Tissue Disease: Evaluated by 3.0T Cardiac Magnetic Resonance Tissue Tracking

The aim of this study was to assess left ventricular (LV) myocardial strain in patients with connective tissue disease (CTD) and compare LV deformation between subgroups of idiopathic inflammatory myopathy (IIM) and non-IIM. Ninety-eight patients with CTD, comprising 56 with IIM and 42 with non-IIM, and 30 healthy subjects were enrolled and underwent 3.0T cardiac magnetic resonance imaging (MRI) scanning. The LV function and strain parameters were measured and assessed. Our result revealed that CTD patients had preserved LV ejection fraction (60.85%) and had significantly decreased global and regional peak strain (PS) in radial, circumferential, and longitudinal directions (all p < 0.05). IIM patients showed significantly reduced global longitudinal PS (GLPS) and longitudinal PS at apical slice, whereas all strain parameters decreased in non-IIM patients. Except GLPS and longitudinal PS at apical slice, all strain parameters in non-IIM patients were lower than those in IIM patients. By Pearson’s correlation analysis, the LV global radial and circumferential PS were correlated to N-terminal pro-brain natriuretic peptide level and LV ejection fraction in both IIM and non-IIM patients. This study indicated that CTD patients showed abnormal LV deformation despite with preserved LVEF. The impairment of LV deformation differed between IIM and non-IIM patients.

Magnetic Resonance Imaging-Detected Myocardial Inflammation and Fibrosis in Rheumatoid Arthritis: Associations With Disease Characteristics and N-Terminal Pro-Brain Natriuretic Peptide Levels

OBJECTIVE

Myocardial dysfunction and heart failure (HF) are increased in rheumatoid arthritis (RA), yet there are few studies of the myocardium in RA.

METHODS

RA patients with no known heart disease or risk factors underwent gadolinium-enhanced cardiac magnetic resonance imaging (MRI). Images were assessed for left-ventricular (LV) structural and functional parameters and for myocardial late gadolinium enhancement (LGE; an indicator of myocardial fibrosis) and T2-weighted imaging (an indicator of active inflammation). We modeled the associations between RA characteristics and N-terminal pro-brain natriuretic protein (NT-proBNP) levels with LGE and T2-weighted imaging. We also assessed whether LGE and/or T2-weighted imaging were associated with abnormal LV structure or dysfunction.

RESULTS

A total of 60 RA patients were studied. LGE was present in 19 (32%) and T2-weighted imaging in 7 (12%), 5 of whom also had LGE. After adjustment for relevant confounders, higher odds of LGE with each swollen joint (odds ratio [OR] 1.87, P = 0.008), each log unit higher C-reactive protein level (OR 3.36, P = 0.047), and each log unit higher NT-proBNP (OR 20.61, P = 0.009) were found. NT-proBNP was also significantly higher (135%) among those with T2-weighted imaging than in those without T2-weighted imaging or LGE. Higher LV mass index and LV mass:end diastolic volume ratio were observed in those with T2-weighted imaging than in those with no myocardial abnormalities and in those with LGE without T2-weighted imaging; however, ejection fraction was not reduced in those with either LGE or T2-weighted imaging.

CONCLUSION

These data suggest that cardiac MRI findings indicating myocardial inflammation/fibrosis are correlated with RA disease activity and alterations in myocardial structure known to precede clinical HF.

Chronic subcutaneous brain natriuretic peptide therapy in asymptomatic systolic heart failure

AIMS

We have previously reported that asymptomatic systolic heart failure (HF) is characterized by an impaired renal response to volume expansion due to lack of activation of urinary cGMP which is corrected by subcutaneous (SQ) BNP. In the current study, we sought to define the cardiorenal response to intravascular volume expansion after 12 weeks of SQ BNP therapy.

METHODS AND RESULTS

We utilized a double-blinded, placebo-controlled study to compare 12 weeks of twice-daily SQ BNP 10 µg/kg (n = 22) or placebo (n = 12) in asymptomatic systolic HF. Subjects underwent two study visits: baseline and after 12 weeks of therapy. At each study visit, echocardiography, renal, and neurohumoral assessments were performed before and after intravascular volume expansion. The primary endpoint was change in urinary sodium excretion in response to volume expansion at 12 weeks, and we observed a greater increase in urinary sodium excretion [166 (77, 290) vs. 15 (-39, 72) mEq/min; P = 0.02] with SQ BNP treatment vs. placebo. Secondary endpoints included change in urine flow and glomerular filtration rate (GFR) in response to volume expansion at 12 weeks. We observed a significant increase in urine flow (P < 0.01) and trend for differential response in GFR (P = 0.08) with SQ BNP treatment vs. placebo.

CONCLUSION

Among patients with asymptomatic systolic HF, twice-daily SQ BNP therapy improved the cardiorenal response to volume expansion at 12-week follow-up. Further studies are warranted to determine if these beneficial physiological observations with chronic natriuretic peptide administration translate into a delay in the progression to symptomatic HF.

Effect of burden and origin sites of premature ventricular contractions on left ventricular function by 7-day Holter monitor

Recent studies have shown that premature ventricular contractions (PVCs) could enlarge the heart, but its risk factors are incompletely understood as a single 24-hour recording cannot reflect the true PVC burden due to day-to-day variability. Our purpose was to investigate the effect of burden and origin sites on left ventricular (LV) function in patients with PVCs by 7-day Holter electrocardiography (ECG). From May 2012 to August 2013, 112 consecutive patients with PVCs were recruited from the authors' affiliated hospital. All patients received 2-dimensional transthoracic echocardiography, 12-lead routing ECG and 7-days Holter ECG. Serum N-terminal pro-brain natriuretic peptide (NT-proBNP) levels were measured. A total of 102 participants with PVCs were included in the final analysis. Origin of PVCs from the tricuspid annulus had the highest burden and NT-proBNP level. LV papillary muscle had a higher LV ejection fraction (EF) level and a lower LV end-systolic dimension (ESD) than other PVC foci (P<0.05). The high burden group had a higher LV end-diastolic dimension (EDD) and LVESD but lower LVEF than the other two groups (P<0.05). Female, older age, physical work, and history of PVCs had a significantly positive correlation with symptoms. Male, older age, physical work, and high burden were positive predictors of enlarged LVEDD, LVESD and higher serum NT-proBNP level, but lower LVEF. Seven-day dynamic ECG Holter monitor showed the true PVC burden on patients with PVCs. PVCs with a lower burden or origin from the LV papillary muscle and the fascicle were relatively benign, while PVCs with a higher burden or origin from the tricuspid annulus may lead to cardiac dysfunction.

Rationale and therapeutic opportunities for natriuretic peptide system augmentation in heart failure

The natriuretic peptide system (NPS) is intimately involved in cardiorenal homeostasis in health, and dysregulation of the NPS plays an important role in the pathophysiology of heart failure (HF). Indeed, the diuretic, vasorelaxation, beneficial remodeling, and potent neurohumoral inhibition of the NPS support the therapeutic development of chronic augmentation of the NPS in symptomatic HF. Further, chronic augmentation of the protective NPS and in early stages of HF may ultimately prevent the progression of HF and reduced subsequent morbidity and mortality. In the current manuscript, we review the rationale for as well as previous and current efforts aimed at chronic therapeutic augmentation of the NPS in HF.

Osteoglycin Prevents Cardiac Dilatation and Dysfunction After Myocardial Infarction Through Infarct Collagen Strengthening

Rationale:

To maintain cardiac mechanical and structural integrity after an ischemic insult, profound alterations occur within the extracellular matrix. Osteoglycin is a small leucine-rich proteoglycan previously described as a marker of cardiac hypertrophy.

Objective:

To establish whether osteoglycin may play a role in cardiac integrity and function after myocardial infarction (MI).

Methods and Results:

Osteoglycin expression is associated with collagen deposition and scar formation in mouse and human MI. Absence of osteoglycin in mice resulted in significantly increased rupture-related mortality with tissue disruption, intramyocardial bleeding, and increased cardiac dysfunction, despite equal infarct sizes. Surviving osteoglycin null mice had greater infarct expansion in comparison with wild-type mice because of impaired collagen fibrillogenesis and maturation in the infarcts as revealed by electron microscopy and collagen polarization. Absence of osteoglycin did not affect cardiomyocyte hypertrophy in the remodeling remote myocardium. In cultured fibroblasts, osteoglycin knockdown or supplementation did not alter transforming growth factor-β signaling. Adenoviral overexpression of osteoglycin in wild-type mice significantly improved collagen quality, thereby blunting cardiac dilatation and dysfunction after MI. In osteoglycin null mice, adenoviral overexpression of osteoglycin was unable to prevent rupture-related mortality because of insufficiently restoring osteoglycin protein levels in the heart. Finally, circulating osteoglycin levels in patients with heart failure were significantly increased in the patients with a previous history of MI compared with those with nonischemic heart failure and correlated with survival, left ventricular volumes, and other markers of fibrosis.

Conclusions:

Increased osteoglycin expression in the infarct scar promotes proper collagen maturation and protects against cardiac disruption and adverse remodeling after MI. In human heart failure, osteoglycin is a promising biomarker for ischemic heart failure.

Value of proBNP1-108 testing for the risk stratification of patients with systolic heart failure

The study objectives were to determine the circulating levels of proBNP1-108, the precursor of B-type natriuretic peptide (BNP) and amino-terminal pro-BNP (NT-proBNP), in patients with systolic heart failure (HF) and to assess their prognosis value for cardiovascular (CV) death over a long-term follow-up. Seventy-three patients with systolic HF and 68 healthy volunteers were included. ProBNP1-108, BNP and NT-proBNP levels were measured with automated immunoassays and their predictive value for long-term survival was assessed through an 8 years follow-up. ProBNP1-108 levels were markedly increased in patients with systolic HF in comparison to healthy volunteers. In univariate proportional hazard model, survival was related to proBNP1-108, BNP, NT-proBNP, age, EF and glomerular filtration rate (eGFR). Kaplan-Meier survival curves according to proBNP tertiles diverged significantly, and the highest proBNP levels were related to patients with the highest risk of CV death. In a multivariate analysis including age, EF, proBNP1-108, BNP, NT-proBNP, and eGFR levels, NT-proBNP was the strongest predictor of long term CV death. Our study therefore demonstrated that high levels of proBNP1-108, measured with an assay with enhanced analytical specificity, are related to the long-term risk of cardiovascular death in systolic heart failure.

New Insights Into Diastolic Dysfunction and Heart Failure With Preserved Ejection Fraction

As the population ages, the incidence of patients presenting for surgical procedures with diastolic dysfunction and heart failure with preserved ejection fraction will rise. This review will discuss the most current and relevant information on the pathophysiology, treatment, and perioperative management of these patients.

Update on diastolic heart failure or heart failure with preserved ejection fraction in the older adults

Nearly half of all heart failure (HF) patients have diastolic HF (DHF) or clinical HF with normal or near-normal left ventricular ejection fraction (LVEF). Although the terminology has not been clearly defined, it is increasingly being referred to as HF with preserved ejection fraction (HFPEF). The prevalence of HFPEF increases with age, especially among older women. Identifying HFPEF is important because the etiology, pathogenesis, prognosis, and optimal management may differ from that for systolic HF (SHF) or HF with reduced ejection fraction. The clinical presentation of HF is similar for both SHF and HFPEF. As in SHF, HFPEF is a clinical diagnosis. Once a clinical diagnosis of HF has been made, the presence of HFPEF can be established by confirming a normal or near-normal LVEF, often by an echocardiogram. HFPEF is often associated with a history of hypertension, concentric left ventricular hypertrophy, vascular stiffness, and left ventricular diastolic dysfunction. As in SHF, HFPEF is also associated with poor outcomes. While therapies with angiotensin-converting enzyme inhibitors and beta-blockers improve outcomes in SHF, there is currently no such evidence of their benefits in older HFPEF patients. In this review recent advances in the diagnosis and management of HFPEF in older adults are discussed.

B-type natriuretic peptide is an independent predictor of endothelial function in man

BNP (B-type natriuretic peptide) has been reported to be elevated in preclinical states of vascular damage. To elucidate the relationship between plasma BNP and endothelial function, we have investigated the relationship between BNP and endothelial function in a cohort of subjects comprising healthy subjects as well as at-risk subjects with cardiovascular risk factors. To also clarify the relative contribution of different biological pathways to the individual variation in endothelial function, we have examined the relationship between a panel of multiple biomarkers and endothelial function. A total of 70 subjects were studied (mean age, 58.1±4.6 years; 27% had a history of hypertension and 18% had a history of hypercholesterolaemia). Endothelium-dependent vasodilatation was evaluated by the invasive ACH (acetylcholine)-induced forearm vasodilatation technique. A panel of biomarkers of biological pathways was measured: BNP, haemostatic factors PAI-1 (plasminogen-activator inhibitor 1) and tPA (tissue plasminogen activator), inflammatory markers, including cytokines [hs-CRP (high sensitive C-reactive protein), IL (interleukin)-6, IL-8, IL-18, TNFα (tumour necrosis factor α) and MPO (myeloperoxidase] and soluble adhesion molecules [E-selectin and sCD40 (soluble CD40)]. The median BNP level in the study population was 26.9 pg/ml. Multivariate regression analyses show that age, the total cholesterol/HDL (high-density lipoprotein) ratio, glucose and BNP were independent predictors of endothelial function, and BNP remained an independent predictor (P=0.009) in a binary logistic regression analysis using FBF (forearm blood flow) as a dichotomous variable based on the median value. None of the other plasma biomarkers was independently related to ACH-mediated vasodilatation. In a strategy using several biomarkers to relate to endothelial function, plasma BNP was found to be an independent predictor of endothelial function as assessed by endothelium-dependent vasodilatation in response to ACH.

Predictive utility of atrial, N-terminal pro-atrial, and N-terminal pro-B-type natriuretic peptides for mortality and cardiovascular events in the general community: a 9-year follow-up study

OBJECTIVE

To determine the predictive value of atrial natriuretic peptide (ANP), N-terminal pro-ANP (NT-proANP), and N-terminal pro-B-type natriuretic peptide (NT-proBNP) for mortality and cardiovascular events in the general population in the absence of overt heart failure (HF).

PARTICIPANTS AND METHODS

We identified a community-based cohort of 2042 individuals. Those with stage C or D HF (n=45) and renal insufficiency (n=6) were excluded from the current study. Of the remaining individuals, 1769 (89%) underwent echocardiography and measurement of plasma ANP, NT-proANP, and NT-proBNP. Participants were followed up from January 1, 1997, to May 1, 2009, for mortality, HF, myocardial infarction (MI), and cerebrovascular accident; median follow-up was 9 years.

RESULTS

After adjustment for conventional clinical risk factors, NT-proANP had significant predictive value for mortality but not for HF, MI, or cerebrovascular accident, whereas ANP lacked any predictive value. The predictive value of NT-proANP for mortality was attenuated after adjustment for structural and functional cardiac abnormalities. In contrast, NT-proBNP had predictive value for mortality, HF, and MI after adjustment for conventional risk factors and retained significance for mortality and HF after adjustment for structural and functional cardiac abnormalities.

CONCLUSION

Our results suggest that NT-proBNP is a more robust cardiac biomarker compared with ANP or NT-proANP and is independently predictive of mortality and HF in the general population free of overt HF.

Predicting mortality and hospital admission in patients with COPD: significance of NT pro-BNP, clinical and echocardiographic assessment

AIMS

To quantify the ability of N-terminal pro-brain natriuretic peptide (NT pro-BNP) to predict mortality and hospitalization in patients with chronic obstructive airways disease (COPD).

METHODS

Prospective single-centre observational study of 140 consecutive patients aged at least 18 years with COPD between 27 March 2004 and 28 February 2008 (median follow-up 3.9 years).

RESULTS

Sixty-five (46%) men, 26 (19%) O2 therapy, 115 (82%) smokers, 38 (27%) patients receiving diuretics, 15 (11%) left-ventricular ejection fraction less than 45%. Median [interquartile range (IQR)] NT pro-BNP concentration 16.2 (25.4) pmol/l. NT pro-BNP was higher in those with a dilated left atrium (P<0.001), aortic stenosis (P=0.02), left-ventricular systolic dysfunction (P=0.027), right ventricular impairment (P=0.011), atrial fibrillation (P<0.001), patients receiving diuretics (P=0.010) and angiotensin-converting enzyme (ACE) inhibitors (P=0.006). One-year mortality and hospitalization rates were 2.9 and 25.4%. The median (IQR) time to hospitalization and length of first hospital stay: 383.5 (605) and 4.0 (7.0) days. NT pro-BNP was an excellent discriminator of right-ventricular impairment (C statistic=0.90) and predicted survival (highest quartile versus lowest quartile relative risk=3.02, P=0.001), but not hospital admission. After adjustment this association was not significant.

CONCLUSION

NT pro-BNP predicts survival, but not hospital admission in patients with COPD. The ability of NT pro-BNP to independently predict death or hospitalization is superseded by the presence of a dilated left atrium, aortic stenosis and left-ventricular systolic dysfunction.

Nitric oxide synthase and cyclic GMP signaling in cardiac myocytes: from contractility to remodeling

Cyclic guanosine 3'5'monophosphate (cGMP) is the common downstream second messenger of natriuretic peptides and nitric oxide. In cardiac myocytes, the physiological effects of cGMP are exerted through the activation of protein kinase G (PKG) signaling, and the activation and/or inhibition of phosphodiesterases (PDEs), providing an integration point between cAMP and cGMP signals. Specificity of cGMP signals is achieved through compartmentalization of cGMP synthesis by guanylate cyclases, and cGMP hydrolysis by PDEs. Increasing evidence suggests that cGMP-dependent signaling pathways play an important role in inhibiting cardiac remodeling, through the inhibition Ca(2+) handling upstream of pathological Ca(2+)-dependent signaling pathways. Thus, enhancing cardiac myocyte cGMP signaling represents a promising therapeutic target for treatment of cardiovascular disease. This article is part of a Special Issue entitled "Local Signaling in Myocytes."

Predictive factors for high brain (B-type) natriuretic peptide at discharge in properly treated heart failure patients

AIM

To study differences and prognostic effect of some factors on brain (B-type) natriuretic peptide (BNP) levels at discharge of patients with chronic heart failure (CHF) treated in accord with current treatment guidelines.

PATIENTS AND METHODS

Eighty-five consecutive patients hospitalized for CHF were recruited into the study. A standardized study protocol was used for them including collection of blood samples for measurement of electrolytes, creatinine at baseline and BNP at discharge. High BNP levels were determined at values above the threshold value for the highest BNP quartile (> or = 463 pg/ml). Linear regression analyses were performed using the SPSS 16.0.

RESULTS

High BNP levels at discharge were measured in 21 (24.7%) of the patients. Patients with persisting high BNP levels, despite the administered correct therapy, had significantly more frequently worse clinical and instrumental characteristics: pulmonary congestion (76.2% vs. 40.6%), IV NYHA functional class (23.8% vs. 4.7%), atrial fibrillation (AF) (71.4% vs. 35.9%) and ischemic etiology of HF (47.6% vs. 15.6%). Multivariate linear regression analysis (F = 7.1, p < 0.001) identified systolic blood pressure (SBP), AF and instrumental data for pulmonary congestion as significant and independent predictors of high BNP at discharge.

CONCLUSIONS

There were statistically significant differences in the distribution and prognostic effect of the studied factors across the BNP levels. CHF patients with hypotension, AF and instrumental evidence for pulmonary congestion at admission are at higher risk of high BNP levels at discharge and require special care and clinical approach.

Elevated NT-proBNP levels should be interpreted in elderly patients presenting with dyspnea

BACKGROUND

B-type natriuretic peptide (BNP) assay is a useful tool in order to diagnose dyspnea due to congestive heart failure (CHF). On the other hand many other diseases could affect BNP levels. The aim of this study was to investigate a group of elderly patients admitted to an Internal Medicine unit because of dyspnea.

PATIENTS AND METHODS

NT-proBNP was assessed in 132 consecutive patients aged 80±6 years because of dyspnea. History data, anthropometric, clinical and biochemical parameters were collected. Renal function was assessed by the CKD-EPI formula. Diagnosis of pulmonary disease such as infections and chronic obstructive disease was considered and was analyzed as a single parameter. Statistical analysis was carried out dividing patients with high NT-proBNP from those with normal NT-proBNP according to the Januzzi cut-off.

RESULTS

NT-proBNP was higher than the normal reference values in 68.7% of patients and its levels increased in the 5 different stages of chronic kidney disease. Subjects with high NT-proBNP had lower haemoglobin levels (11.6±2.1 vs 12.8±1.9 g/dl, p=0.003), higher prevalence of atrial fibrillation (54.3 vs 25%, p=0.001), and lower prevalence of pulmonary diseases (29.7 vs 57.5%, p=0.005). Logistic regression analysis showed that NT-proBNP levels were independently associated with haemoglobin (OR 1.307 95% CI 1.072-1.593, p=0.008) and pulmonary diseases (OR 3.069 95% CI 1.385-6.801, p=0.006).

CONCLUSIONS

A disease different from CHF appears to affect NT-proBNP plasma levels. Therefore, determination of its levels does not seem to help clinicians in the definition of dyspnea in elderly people with different comorbidities.

Increased serum N-terminal pro-B-type natriuretic peptide levels in patients with medial arterial calcification and poorly compressible leg arteries

OBJECTIVE

To determine whether serum levels of N-terminal (NT) pro-B-type natriuretic peptide (pro-BNP) are higher in patients with poorly compressible arteries (PCA) than in patients with peripheral artery disease (PAD) and control subjects without PCA or PAD.

METHODS AND RESULTS

Medial arterial calcification in the lower extremities results in PCA and may be associated with increased arterial stiffness and hemodynamic/myocardial stress. PCA was defined as having an ankle-brachial index >1.4 or an ankle blood pressure >255 mm Hg, whereas PAD was defined as having an ankle-brachial index ≤0.9. Study participants with PCA (n=100; aged 71±10 years; 70% men) and age- and sex-matched patients with PAD (n=300) were recruited from the noninvasive vascular laboratory. Age- and sex-matched controls (n=300) were identified from a community-based cohort and had no history of PAD. NT pro-BNP levels were approximately 2.5-fold higher in patients with PCA than in patients with PAD and approximately 4-fold higher than in age- and sex-matched controls. In multivariable regression analyses that adjusted for age, sex, smoking, hypertension, history of coronary heart disease/stroke, systolic blood pressure, and serum creatinine, NT pro-BNP levels remained significantly higher in patients with PCA than in patients with PAD and controls (P<0.001).

CONCLUSIONS

Patients with medial arterial calcification and PCA have higher serum levels of NT pro-BNP than patients with PAD and controls, which is suggestive of an adverse hemodynamic milieu and increased risk for adverse cardiovascular outcomes.

Increases in B-type natriuretic peptide after acute mental stress in heart failure patients are associated with alcohol consumption

OBJECTIVE

The aim of this study was to investigate in heart failure (HF) patients whether acute mental stress induces increases in the HF-severity biomarker B-type natriuretic peptide (BNP) and if alcohol consumption is associated with such stress-induced increases.

METHOD

Twenty-one male HF patients and 19 male non-HF controls (M = 56 years, SEM = 2) underwent a 15-minute acute mental stress test combining public speaking and mental arithmetic. Plasma levels of BNP were determined immediately before as well as 2 hours after the stress test. Alcohol consumption was assessed by self-reported number of drinks per month and history of use.

RESULTS

HF patients had higher BNP levels before and after stress, F(1, 38) = 23.42, p < .001, and showed greater stress-induced increases in BNP levels, F(1, 38) = 4.52, p = .04, compared with controls. HF status (beta = .32, p = .015, deltaR(2) = .10) and higher alcohol consumption ((beta = .61, p< .001, deltaR(2) = .37) were independently associated with higher BNP stress increases. Moreover, higher alcohol consumption moderated the greater BNP stress increases in HF patients but not in controls (p = .49, p < .001, delta(2) = .20), although alcohol consumption did not differ between groups.

CONCLUSIONS

For individuals with HF, particularly those who drink moderate to more substantial amounts of alcohol, exposure to acute psychological stress leads to increases in circulating levels of BNP, a biomarker which is associated with increased morbidity and mortality in HF.

Atrial fibrillation after thoracic surgery for lung cancer: use of a single cut-off value of N-terminal pro-B type natriuretic peptide to identify patients at risk

Postoperative atrial fibrillation (AF) is a well-known complication occurring after thoracic surgery. B-type natriuretic peptide has recently been investigated as a predictive marker of postoperative AF after cardiac surgery. The aim of this study was to evaluate a definite cut-off for N-terminal pro-B type natriuretic peptide (NT-proBNP) in predicting postoperative AF in lung cancer patients. NT-proBNP was determined before and after surgery in 400 patients. Cardiac function was monitored by continuous postoperative ECG and clinical cardiological evaluation. AF occurred in 18% of the patients. Receiver operating characteristic curve analyses identified a cut-off of 182.3 ng l(-1) as the one with the highest sensitivity and specificity. Perioperative increased levels of NT-proBNP seem to predict postoperative AF in patients undergoing thoracic surgery, and a single cut-off of 182.3 ng l(-1) can be used to select high-risk patients who could receive preventive therapy, leading to a considerable decrease in the total costs associated with the management of this complication.

Clinical implications of defective B-type natriuretic peptide

Our understanding of the natriuretic peptide system continues to evolve rapidly. B-type natriuretic peptide (BNP), originally thought to be a simple volume-regulating hormone that is produced in response to cardiac stretch, has been shown to also play important roles in modulating bronchodilation, endothelial function, and cardiac remodeling. Recent data demonstrate that elevated levels of BNP in patients with heart failure do not represent a simple ratcheting up of normal production in response to increased stimulus. Instead, we now know that chronic stimulation of BNP synthesis induces a reversion to fetal gene expression, resulting in production of high molecular weight forms of BNP that are functionally deficient. Standard point-of-care BNP assays are immunoassays that will detect any molecule containing the target epitopes. Consequently, these assays cannot distinguish between defective, high molecular weight forms of BNP and normal, physiologically active BNP. In 2 separate evaluations, mass spectroscopy detected little, if any, normal BNP in patients with heart failure, despite the appearance of high circulating levels of immunoreactive BNP (iBNP) using commercial assays. Therefore, these commercial assays should be considered to be only an indication of myocardial stress. They do not measure physiologic BNP activity. This accounts for the "BNP paradox," namely, that administration of exogenous recombinant human BNP (rhBNP, nesiritide) has substantial clinical and hemodynamic impact in the presence of high levels of circulating iBNP using commercial assays. In addition to its short-term hemodynamic impact, rhBNP may have other important effects in this setting, and further investigation is warranted.

Chronic treatment with clenbuterol modulates endothelial progenitor cells and circulating factors in a murine model of cardiomyopathy

The purpose of this study was to determine the effects of chronic treatment with the beta 2 adrenergic receptor agonist clenbuterol on endothelial progenitor cells (EPC) in a well-characterized model of heart failure, the muscle LIM protein knockout (MLP(-/-)) mouse. MLP(-/-) mice were treated daily with clenbuterol (2 mg/kg) or saline subcutaneously for 6 weeks. Clenbuterol led to a 30% increase in CD31(+) cells in the bone marrow of MLP(-/-) heart failure mice (p < 0.004). Clenbuterol did not improve ejection fraction. Clenbuterol treatment in MLP(-/-) mice was associated with significant changes in the following circulating factors: tissue inhibitor of metalloproteinase-type 1, leukemia inhibitory factor 1, C-reactive protein, apolipoprotein A1, fibroblast growth factor 2, serum glutamic oxaloacetic transaminase, macrophage-derived chemokine, and monocyte chemoattractant protein-3. Clenbuterol treatment in the MLP(-/-) model of heart failure did not rescue heart function, yet did increase CD31(+) cells in the bone marrow. This is the first evidence that a beta 2 agonist increases EPC proliferation in the bone marrow in a preclinical model of heart failure.

Hospitalized patients with acute decompensated heart failure: recognition, risk stratification, and treatment review

Acute decompensated heart failure (ADHF) has emerged as a major healthcare problem. It causes approximately 3% of all hospitalizations in the United States, with the direct medical cost of these hospitalizations estimated at $18.8 billion per year. Early recognition, risk stratification, and evidence-based treatment are crucial in reducing the morbidity, mortality, and costs associated with this disorder. Classic signs and symptoms of ADHF, such as rales, dyspnea, and peripheral edema, may be absent at hospital presentation and, even when present, are not specific to this disorder. As a result, serum B-type natriuretic peptide level is now used to rapidly and accurately detect ADHF. Multivariate analyses have identified renal dysfunction, hypotension, advanced age, hyponatremia, and comorbidities as significant and independent mortality risk factors. Based on these factors, mortality risk can be stratified from very low to very high using published algorithms that have been validated in independent populations. Evidence-based guidelines for the treatment of ADHF are available from both the European Society of Cardiology and the Heart Failure Society of America. In general, an intravenous loop diuretic, either alone or in combination with a vasodilator, is recommended as initial therapy in patients with volume overload, depending on the patient's clinical status. Use of inotropic agents should be limited to the small subset of patients with low-output syndrome and significant hypotension. In any event, frequent monitoring of clinical response is essential, with subsequent therapy determined by this response. Finally, focused patient education during hospitalization may help reduce readmissions for ADHF.

The association between disease activity and NT-proBNP in 238 patients with rheumatoid arthritis: a 10-year longitudinal study

Introduction

Disease activity in patients with rheumatoid arthritis (RA) is associated with increased cardiovascular morbidity and mortality, of which N-terminal pro-brain natriuretic peptide (NT-proBNP) is a predictor. Our objective was to examine the cross-sectional and longitudinal associations between markers of inflammation, measures of RA disease activity, medication used in the treatment of RA, and NT-proBNP levels (dependent variable).

Methods

Two hundred thirty-eight patients with RA of less than 4 years in duration were followed longitudinally with three comprehensive assessments of clinical and radiographic data over a 10-year period. Serum samples were frozen and later batch-analyzed for NT-proBNP levels and other biomarkers. Bivariate, multivariate, and repeated analyses were performed.

Results

C-reactive protein (CRP) levels at baseline were cross-sectionally associated with NT-proBNP levels after adjustment for age and gender (r² adjusted = 0.23; P < 0.05). At the 10-year follow-up, risk factors for cardiovascular disease were recorded. Duration of RA and CRP levels were independently associated with NT-proBNP in the final model that was adjusted for gender, age, and creatinine levels (r² adjusted = 0.38; P < 0.001). In the longitudinal analyses, which adjusted for age, gender, and time of follow-up, we found that repeated measures of CRP predicted NT-proBNP levels (P < 0.001).

Conclusion

CRP levels are linearly associated with levels of NT-proBNP in cross-sectional and longitudinal analyses of patients with RA. The independent associations of NT-proBNP levels and markers of disease activity with clinical cardiovascular endpoints need to be further investigated.

Sleep disordered breathing in chronic heart failure

Heart failure is a growing problem, placing an increasing burden on public health resources and continuing to exert a high toll in mortality and morbidity. Sleep disordered breathing (SDB) is also a major public health problem and is associated with an increased risk of fatal and non-fatal cardiovascular events. Current evidence suggests SDB, particularly central SDB, is more prevalent in patients with chronic heart failure (CHF) than in the general population, but is under-diagnosed as SDB symptoms are less prevalent in CHF. This is further hampered by the absence of a simple and accurate screening tool and limited access to sleep facilities to diagnose SDB in the large numbers of patients with CHF. The presence of SDB in patients with CHF imposes increased haemodynamic burdens and results in autonomic abnormalities. Central SDB is an independent marker of worse prognosis, and evidence is increasing that obstructive SDB is also associated with higher mortality in patients with CHF. Optimal treatment of central SDB in these patients remains uncertain. While evidence of efficacy of positive pressure ventilation is stronger in obstructive SDB, improvement in survival for patients with both CHF and SDB awaits definitive trials. This paper summarizes our current understanding of the pathophysiology of SDB in CHF, and the cardiovascular consequences, and reviews the evidence for the beneficial effects of treatment of SDB in patients with CHF.

RT-ABCDE strategy for management and prevention of human diseases

In this article, the authors summarized the RT-ABCDE strategy for the management and prevention of human diseases, which includes ReTro-ABCDE (Examination regularity, Disease and risk factor control, Changing lifestyle and reducing pathways of infection and spread, Biochemical and Antagonistic index control and therapeutic treatment as well as RT--Routine and Right Treatment). The RT-ABCDE strategy, a novel concept and an essential method, should be a routine strategy for disease control and prevention. It should be proposed and applied in both clinical and preventive medicine.

Protein C: a potential biomarker in severe sepsis and a possible tool for monitoring treatment with drotrecogin alfa (activated)

Introduction

Drotrecogin alfa (activated; DrotAA) treatment, a 96-hour infusion, reduces 28-day mortality in severe sepsis to approximately 25%. The question remains whether a longer infusion or higher dose could increase rate of survival. The goal of this study was to identify a dependable, sensitive measure with which to monitor disease progression and response in patients during DrotAA treatment.

Methods

Data on severe sepsis patients included in PROWESS (placebo-controlled, double-blind, randomized study of 850 DrotAA and 840 placebo individuals) and ENHANCE (single-arm, open-label study of 2,375 DrotAA patients) studies were analyzed. In these studies, DrotAA (24 μg/kg per hour) or placebo was infused for 96 hours and patients were followed for 28 days. Data on six laboratory measures and five organ dysfunctions were systematically analyzed to identify a potential surrogate end-point for monitoring DrotAA therapy and predicting 28-day mortality at the end of therapy. To allow comparison across variables, sensitivity and specificity analyses identified cut-off values for preferred outcome, and relative risks for being above or below cut-offs were calculated, as was the 'proportion of treatment effect explained' (PTEE) to identify biomarkers that contribute to benefit from DrotAA.

Results

Protein C was the only variable that correlated with outcome across all analyses. Using placebo data, a baseline protein C under 40% was established as a useful predictor of outcome (odds ratio 2.12). Similar odds ratios were associated with cut-off values of other biomarkers, but the treatment benefit associated with DrotAA was significantly greater below the cut-off than above the cut-off only for protein C (relative risk for 28-day mortality 0.66 versus 0.88; P = 0.04). Protein C was the only end-of-infusion biomarker that potentially explained at least 50% of the benefit from DrotAA (PTEE 57.2%). The PTEE was 41% for cardiovascular Sequential Organ Failure Assessment score and for d-dimer. At the end of infusion (day 4), protein C categories (≤40%, 41% to 80%, and > 80%) remained significantly related to mortality, regardless of treatment assignment.

Conclusion

Based on systematic analyses of 11 variables measured in severe sepsis clinical trials, protein C was the only variable consistently correlated with both DrotAA treatment effect and survival. Further study is needed to determine whether longer infusions or higher doses of DrotAA would achieve the goal of normalizing protein C in more patients with severe sepsis.