Natriuretic peptides (BNP and NT-proBNP): measurement and relevance in heart failure

In-hospital and long-term outcomes of congestive heart failure: Predictive value of B-type and amino-terminal pro-B-type natriuretic peptides and their ratio

Relative changes in B-type natriuretic peptide (BNP) and amino terminal pro-BNP (NT-proBNP) levels may help to assess the risk of congestive heart failure (CHF). However, whether these levels at the time of admission enable the prediction of outcomes with acute exacerbation remains unknown. The current study determined the abilities of BNP, NT-proBNP and their ratio to predict in-hospital and long-term outcomes of patients with CHF. Patients who were admitted to the cardiac care unit of Juntendo University Hospital (Tokyo, Japan) with acute CHF onset were consecutively enrolled into the present observational study. Serum levels of BNP and NT-proBNP were immediately measured on admission, and other biomarkers and clinical data were also investigated. Of 195 enrolled patients, 16 (8.2%) succumbed to CHF in hospital and 124 (69.3%) reached the endpoint of mortality or readmission following a median follow-up of 14 months. Multiple linear regression analysis revealed body mass index, low density lipoprotein cholesterol, hemoglobin, estimated glomerular filtration rate and C-reactive protein as independent predictors of the NT-proBNP/BNP ratio. BNP, NT-proBNP and their ratio were significantly higher among those who succumbed to CHF than in those who remained alive in hospital (P<0.05). Logistic regression analysis indicated that the ratio was an independent predictor for in-hospital mortality and long-term outcomes. In conclusion, the ratio of NT-proBNP to BNP more effectively predicts in-hospital outcomes than either factor alone and it may also help to predict outcomes among patients with acute exacerbation of HF.

Cardiovascular diseases related to ionizing radiation: The risk of low-dose exposure (Review)

Traditionally, non-cancer diseases are not considered as health risks following exposure to low doses of ionizing radiation. Indeed, non-cancer diseases are classified as deterministic tissue reactions, which are characterized by a threshold dose. It is judged that below an absorbed dose of 100 mGy, no clinically relevant tissue damage occurs, forming the basis for the current radiation protection system concerning non-cancer effects. Recent epidemiological findings point, however, to an excess risk of non-cancer diseases following exposure to lower doses of ionizing radiation than was previously thought. The evidence is the most sound for cardiovascular disease (CVD) and cataract. Due to limited statistical power, the dose-risk relationship is undetermined below 0.5 Gy; however, if this relationship proves to be without a threshold, it may have considerable impact on current low-dose health risk estimates. In this review, we describe the CVD risk related to low doses of ionizing radiation, the clinical manifestation and the pathology of radiation-induced CVD, as well as the importance of the endothelium models in CVD research as a way forward to complement the epidemiological data with the underlying biological and molecular mechanisms.

[Dyspnea. From the concept up to diagnostics]

Dyspnea represents one of the most frequent and heterogeneous symptoms. The term dyspnea describes the subjective perception of an inadequate effort to breathe. In general, acute and chronic forms have to be differentiated. Due to its prognostic implications a structured work-up to find the correct diagnosis is of great importance. Depending on the condition of the patient, simple algorithms including biomarkers, an electrocardiogram, echocardiography and other imaging procedures are used when needed. Especially in its acute appearance life-threatening situations, such as myocardial ischemia, heart failure, pulmonary embolism and pneumothorax have to be rapidly and effectively excluded in the differential diagnostics. In contrast, the underlying diseases in chronic dyspnea are bronchial asthma, chronic obstructive airway diseases, heart failure and a combination of obesity and deconditioning in up to 85 % of all cases. The differential diagnosis needs a structured approach including anamnestic and medical technical methods, aiming an efficient differentiation of cardiac and pulmonary causes. As a high number of patients suffer from more than one significant disease, the differential diagnostic assessment needs to be focused on the assessment of the predominant cause of the dyspnea. For this purpose, exercise tests provide helpful algorithms to answer this question.

Prognostic prediction of troponins in cardiac myxoma: case study with literature review

Objective

It was supposed that troponins in cardiac myxoma patients might be in a same fashion as in the conditions without myocardial injury. In order to verify this hypothesis, troponins in cardiac myxoma patients were discussed by presenting a comprehensive retrieval of the literature with incorporating the information of a recent patient.

Methods

Postoperative detections of troponin I, creatine kinase isoenzyme MB (CK-MB) and N-terminal pro-B-type natriuretic peptide revealed elevated troponin I and CK-MB and normal N-terminal pro-B-type natriuretic peptide. Postoperative troponin I and CK-MB shared a same trend, reaching a peak value at postoperative hour 2, gradually decreased on postoperative day 1, and reached a plateau on postoperative days 7 and 13. A significant correlation could be noted between the postoperative values of the two indicators (Y=0.0714X + 0.6425, r²=0.9111, r=0.9545, P=0.0116). No significant linear correlation between troponin I and N-terminal pro-B-type natriuretic peptide were found. Literature review of troponins in cardiac myxoma patients revealed the uncomplicated patients had a normal or only slightly elevated troponin before open heart surgery. However, the complicated patients (with cerebral or cardiac events) showed a normal preoperative troponin in 3 (23.1%) and an elevated troponin in 10 (76.9%) patients (χ²=7.54, P=0.0169, Fisher's exact test). The overall quantitative result of troponin I was 2.45±2.53 µg/L, and that of troponin T was 3.10±4.29 mg/L, respectively.

Conclusion

Troponins are not necessarily elevated in patients with a cardiac myxoma without coronary syndrome. By contrast, patients with a cardiac myxoma with an elevated troponin may herald the presence of an associated coronary event. An old cerebral infarct does not necessarily cause an elevation of troponin or B-type natriuretic peptide, or new neurological events, but might lead to a delayed awakening.

Association of menopause age and N-terminal pro brain natriuretic peptide: the Multi-Ethnic Study of Atherosclerosis

OBJECTIVE

Menopause age can affect the risk of developing cardiovascular disease (CVD). The purpose of this study was to investigate the associations of early menopause (menopause occurring before age 45 y) and menopause age with N-terminal pro brain natriuretic peptide (NT-proBNP), a potential risk marker of CVD and heart failure.

METHODS

Our cross-sectional study included 2,275 postmenopausal women, aged 45 to 85 years and without clinical CVD (2000-2002), from the Multi-Ethnic Study of Atherosclerosis. Participants were classified as having or not having early menopause. NT-proBNP was log-transformed. Multivariable linear regression was used for analysis.

RESULTS

Five hundred sixty-one women had early menopause. The median (25th-75th percentiles) NT-proBNP value was 79.0 (41.1-151.6) pg/mL for all participants, 83.4 (41.4-164.9) pg/mL for women with early menopause, and 78.0 (40.8-148.3) pg/mL for women without early menopause. The mean (SD) age was 65 (10.1) and 65 (8.9) years for women with and without early menopause, respectively. No significant interactions between menopause age and ethnicity were observed. In multivariable analysis, early menopause was associated with a 10.7% increase in NT-proBNP levels, whereas each 1-year increase in menopause age was associated with a 0.7% decrease in NT-proBNP levels.

CONCLUSIONS

Early menopause is associated with greater NT-proBNP levels, whereas each 1-year increase in menopause age is associated with lower NT-proBNP levels, in postmenopausal women.

Diagnostic values of NT-proBNP in acute dyspnea among elderly patients

The study aims to evaluate a rapid testing of NT-proBNP in differential diagnosis of cardiac and pulmonary dyspnea among elderly emergency patients. Two hundred sixty-eight dyspnea patients with ages of ≥60 years old participated in the study. Based on their clinical diagnosis, the patients were divided into three groups: group A diagnosed with pulmonary dyspnea (PD), group B diagnosed with congestive heart failure (CHF), and group C diagnosed with combined dyspnea (CHF+PD). NT-proBNP levels among the three groups were compared. NT-proBNP levels in group A were significantly lower than those in groups B and C. No significant difference was observed between groups B and C in terms of NT-proBNP levels (P>0.05). Our data showed that NT-proBNP levels in patients with cardiac dyspnea were significantly higher than those in patients with pulmonary dyspnea. Person linear association analysis revealed that NT-proBNP levels were reversely associated with LVEF (r=-0.675, P<0.01), indicating that higher NT-proBNP levels result in lower LVEF and poorer heart functions. NT-proBNP is a valuable biomarker in differential diagnosis of pulmonary and cardiac dyspnea among elderly patients due to the high sensitivity of the testing method and the strong association with the severity of heart failure.

DPP4 in Diabetes

Dipeptidyl-peptidase 4 (DPP4) is a glycoprotein of 110 kDa, which is ubiquitously expressed on the surface of a variety of cells. This exopeptidase selectively cleaves N-terminal dipeptides from a variety of substrates, including cytokines, growth factors, neuropeptides, and the incretin hormones. Expression of DPP4 is substantially dysregulated in a variety of disease states including inflammation, cancer, obesity, and diabetes. Since the incretin hormones, glucagon-like peptide-1 and glucose-dependent insulinotropic polypeptide (GIP), are major regulators of post-prandial insulin secretion, inhibition of DPP4 by the gliptin family of drugs has gained considerable interest for the therapy of type 2 diabetic patients. In this review, we summarize the current knowledge on the DPP4–incretin axis and evaluate most recent findings on DPP4 inhibitors. Furthermore, DPP4 as a type II transmembrane protein is also known to be cleaved from the cell membrane involving different metalloproteases in a cell-type-specific manner. Circulating, soluble DPP4 has been identified as a new adipokine, which exerts both para- and endocrine effects. Recently, a novel receptor for soluble DPP4 has been identified, and data are accumulating that the adipokine-related effects of DPP4 may play an important role in the pathogenesis of cardiovascular disease. Importantly, circulating DPP4 is augmented in obese and type 2 diabetic subjects, and it may represent a molecular link between obesity and vascular dysfunction. A critical evaluation of the impact of circulating DPP4 is presented, and the potential role of DPP4 inhibition at this level is also discussed.

Plasma N-terminal pro-B-type natriuretic peptide concentration in healthy retired racing Greyhounds

BACKGROUND

N-terminal pro-B-type natriuretic peptide (NT-proBNP) is a cardiac biomarker whose plasma concentration is high in some dogs with cardiopulmonary disease. NT-proBNP is a diagnostic tool that can be used to help determine if a patient has congestive heart failure. Greyhounds have functional heart murmurs, relative cardiomegaly, and high serum cTnI concentration.

OBJECTIVES

The purpose of the study was to evaluate the plasma concentration of NT-proBNP in healthy Greyhounds and compare it to non-Greyhound dogs.

METHODS

We prospectively evaluated healthy client-owned dogs including retired racing Greyhounds and non-Greyhounds. Plasma was obtained and transferred into tubes containing a protease inhibitor and submitted for a specific NT-proBNP ELISA assay.

RESULTS

The plasma NT-proBNP concentration in Greyhounds was significantly higher than in non-Greyhound control dogs (946 vs 632 pmol/L; P < .005); 46% of Greyhounds had NT-proBNP > 1000 pmol/L.

CONCLUSIONS

Plasma NT-proBNP concentration in Greyhounds is high and should be interpreted with caution.

DECREASED LEFT VENTRICULAR CONTRACTILITY AND VENTRICULAR-ARTERIAL MATCHING INDEX CORRELATION WITH N-TERMINAL PRO B-TYPE NATRIURETIC PEPTIDE IN HEART FAILURE

This study is aimed to assess (1) Left ventricle (LV) contractile function and ventricular-arterial matching from echocardiography; (2) whether ventricular-arterial matching (VAM) is associated with N-terminal pro B-type natriuretic peptide (NT-proBNP), and stroke output in patients with heart failure. Normal subjects (n = 81) and heart failure patients (n = 80) underwent echocardiography, Doppler echocardiography and tissue Doppler imaging. Only heart failure patients underwent blood test for NT-proBNP. The LV contractility was calculated as dσ ⁎ /dt max = 3 × (dV/dt) max /2V m = 3 × V peak × (π × D2/4)/(2V m ), and the arterial elastance was calculated as Ea = SBP × 0.9/ SV , wherein V peak and D are peak velocity and diameter of LV outflow tract, Vm is myocardial volume, SBP is the systolic blood pressure and SV is stroke volume measured from LVOT. The VAM index was expressed as the ratio of LV contractility to arterial elastance (dσ ⁎ /dt max /Ea). We found that HF patients had (i) decreased dσ ⁎ /dt max (1.46 ± 0.73 versus 4.06 ± 1.06 s-1), (ii) increased Ea (2.90 ± 0.87 versus 1.81 ± 0.38 mmHg/mL), and (iii) attenuated ventricular-arterial matching index (0.66 ± 0.57 versus 2.38 ± 0.91 mL/mmHg⋅s) (all p < 0.001) compared with normal subjects. The VAM index was correlated inversely with NT-proBNP (r = -0.32, p < 0.05), but positively with the stroke volume (r = 0.85, p < 0.001). The VAM index of < 1.51 was able to clearly differentiate the failing heart from normal hearts (AUC = 0.959, Sensitivity = 0.911, Specificity = 0.905). Heart failure patients demonstrated impaired ventricular contractility, enhanced arterial stiffening, and attenuated ventricular-arterial matching index. The attenuated ventricular-arterial matching index value was associated with elevated NT-proBNP levels and lower cardiac output.

Copeptin (C-terminal pro arginine-vasopressin) is an independent long-term prognostic marker in heart failure with reduced ejection fraction

BACKGROUND

The level of copeptin, a stable fragment of pro-arginine-vasopressin (AVP), correlates with disease severity. It is an established, short-term prognostic marker for patients with heart failure with reduced ejection fraction (HFREF). We aimed to examine the association between copeptin and long-term mortality. We also studied the clinical usefulness of copeptin as a prognostic biomarker by analysing the improvement of net reclassification.

METHODS

Copeptin concentrations were measured in a cohort of 195 consecutive patients with HFREF. Disease severity and clinical parameters were determined at baseline, and all-cause mortality was recorded after five-year follow-up.

RESULTS

One hundred and ten patients died during the five-year follow-up (five-year mortality rate: 0.56). Univariate analysis identified copeptin (HR 2.168 [95% CI 1.740-2.700]) as a predictor of mortality. The final, multivariable Cox survival model identified a number of independent predictors of death. These included higher NHYA functional class, previous MI, at least one hospitalisation for worsening HF (within the two years before inclusion into the study), elevated blood urea nitrogen, NT-proBNP-, and copeptin levels, as well as increased red blood cell distribution width, and decreased GFR. The addition of copeptin alone to the baseline predictive model (NT-proBNP only) resulted in a minor (8.21%) improvement, whereas the final, multivariable model showed a significant increase in net reclassification (10.26%, p=0.015).

CONCLUSIONS

These data indicate that copeptin is an independent long-term prognostic marker in HFREF, with possible clinical relevance for multimarker risk prediction algorithms.

Prognostic role of troponin and natriuretic peptides as biomarkers for deterioration of left ventricular ejection fraction after chemotherapy

Cardiotoxicity due to anthracyclines, trastuzumab and other potential cardiotoxic drugs is still a problem of modern chemotherapy. For years researchers have tried to find biological markers that can predict changes in the heart. The most thoroughly tested markers are troponin and natriuretic peptides. Some studies have proven that these markers can indeed be useful. In studies which have shown the predictive role of troponin I the assessment of this marker was performed very frequently. It is not possible to carry out such serial measurements in many centers because of typical 1-day hospital stay times. The predictive role of natriuretic peptides still needs further investigation. This review considers the newest research from recent years.

Utility of point-of-care testing of natriuretic peptides (brain natriuretic peptide and n-terminal pro-brain natriuretic peptide) in the emergency department

Rapid and accurate diagnosis of a patient with an acute disease is a challenge for emergency physicians. Natriuretic peptides have emerged as important tools for diagnosis, risk stratification and therapeutic decision making for some categories of emergency patients. Brain natriuretic peptide (BNP) is a member of a four natriuretic peptides family that shares a common 17-peptide ring structure. Atrial natriuretic peptide, C-natriuretic peptide (CNP), and D-type natriuretic peptide are the other natriuretic peptide, which share the same common 17-peptide ring structure. The N-terminal fragment of pro-BNP, N-terminal pro-brain natriuretic peptide (NT-proBNP) consists of 76 amino acids, which is biologically inert, while the active component BNP contains 32 amino acids. BNP and NT-proBNP are secreted in the plasma in equimolar quantities and are frequently used in the diagnosis of congestive heart failure, and distinguishing between patients with dyspnea of cardiac or pulmonary origin. Both natriuretic peptides have also been evaluated for use in the assessment and management of several other conditions including sepsis, cirrhosis of liver and renal failure. However, one should remember that the values of natriuretic peptides are affected by age and weight of the patients, and presence of several comorbidities such as chronic renal failure, type 2 diabetes mellitus, anemia, pulmonary embolism, and acute coronary syndrome. Values of these peptides also vary depending on the type of test used. The performance characteristics of these natriuretic peptides vary depending on the patients on whom they are used. Therefore determination of reference values for these peptides represents a challenge.

An antibody reactive to the Gly63-Lys68 epitope of NT-proBNP exhibits O-glycosylation-independent binding

The N-terminal fragment of prohormone brain natriuretic peptide (NT-proBNP) is a commonly used biomarker for the diagnosis of congestive heart failure, although its biological function is not well known. NT-proBNP exhibits heavy O-linked glycosylation, and it is quite difficult to develop an antibody that exhibits glycosylation-independent binding. We developed an antibody that binds to the recombinant NT-proBNP protein and its deglycosylated form with similar affinities in an enzyme immunoassay. The epitope was defined as Gly₆₃–Lys₆₈ based on mimetic peptide screening, site-directed mutagenesis and a competition assay with a peptide mimotope. The nearest O-glycosylation residues are Thr₅₈ and Thr₇₁; therefore, four amino acid residues intervene between the epitope and those residues in both directions. In conclusion, we report that an antibody reactive to Gly₆₃–Lys₆₈ of NT-proBNP exhibits O-glycosylation-independent binding.

NT-proBNP, blood pressure, and cognitive decline in the oldest old: The Leiden 85-plus Study

OBJECTIVE

To study the relation between N-terminal pro-brain natriuretic peptide (NT-proBNP) levels, used as a marker of heart failure in clinical practice, blood pressure (BP), and cognitive decline in the oldest old.

METHODS

In 560 participants of the Leiden 85-plus Study, we measured NT-proBNP levels and BP at age 85 years, at baseline, and global cognitive function (Mini-Mental State Examination [MMSE]) annually during the follow-up of 5 years.

RESULTS

Subjects in the highest tertile of NT-proBNP levels scored 1.7 points lower on the MMSE at age 85 years than subjects in the lowest tertile (p = 0.004), and had a 0.24-point-steeper decline in MMSE score per year (p = 0.021). The longitudinal association disappeared after full adjustment for possible confounders (0.14-point-steeper decline, p = 0.187). Subjects in the category "highest tertile of NT-proBNP and the lowest tertile of systolic BP" had a 3.7-point-lower MMSE score at baseline (p < 0.001) and a 0.49-point-steeper decline in MMSE score per year (p < 0.001) compared with subjects in the other categories.

CONCLUSIONS

In the oldest old, high NT-proBNP levels are associated with lower MMSE scores. The combination of high NT-proBNP levels and low systolic BP is associated with worst global cognitive function and the steepest cognitive decline. Possibly, a failing pump function of the heart results in lower BP and lower brain perfusion with resultant brain dysfunction.

Dual-energy CT pulmonary angiography in patients with suspected pulmonary embolism: value for the detection and quantification of pulmonary venous congestion

OBJECTIVE

To evaluate if vascular and pulmonary parenchymal enhancement values in dual-energy (DE) CT pulmonary angiography (CTPA) can suggest the diagnosis of pulmonary congestion.

METHODS

DE-CTPA images of 90 out of 1321 patients negative for pulmonary embolism showed signs of congestive heart failure. We measured DE-derived pulmonary parenchymal [perfused blood volume (PBV)], pulmonary artery (PA) and left atrium (LA) enhancement values in these patients and in 142 control patients. Enhancement values were compared between the populations and correlated with serum values of B-type natriuretic peptide (BNP) and proBNP, where available.

RESULTS

No significant difference of PBV but significant differences of mean PA and LA enhancement and individual enhancement differences (PA - LA) were found between the populations. PA - LA was higher in patients with elevated BNP and proBNP and was positively correlated with these values. Receiver operating characteristic analysis revealed a moderate discriminatory power of the PA - LA difference for the presence of cardiac biomarker elevations.

CONCLUSION

PBV in DE-CTPA is not altered in patients with signs of congestive heart failure. However, differences in enhancement values in the pre- and post-pulmonary vessels were found in comparison with the control population.

ADVANCES IN KNOWLEDGE

Altered pulmonary vascular haemodynamics in pulmonary venous congestion are not reflected in dual-energy-derived PBV maps. In the diagnosis of left heart failure in patients with chest pain and dyspnoea, density measurements in the pulmonary artery and in the left atrium in CTPA images may be a helpful diagnostic tool.

Association of N-terminal pro-brain natriuretic peptide and hemodynamic parameters measured by impedance cardiography in patients with essential hypertension

The aim of this study was to evaluate the association of NT-proBNP with clinical and hemodynamic assessment in 156 patients with arterial hypertension. NT-proBNP correlated positively with, i.e. age (r=0.310, p=0.00008), mean blood pressure (MBP; r=0.199, p=0.0136), Heather index (HI; r=0.375, p<0.00001) and negatively with thoracic fluid content (TFC; r=-0.300, p=0.0002). The patients with higher NT-proBNP were older (46.1 versus 40.6 years, p=0.001), with higher MBP (102.6 versus 98.5 mm Hg, p=0.0043), HI (14.54 versus 11.93 Ohm s2, p=0.009) and lower TFC (27.5 versus 29.4 1/kOhm, p=0.0032). The independent predictors of higher NT-proBNP were: age, MBP and HI.

A Randomized Controlled Trial to Study the Effect of Yoga Therapy on Cardiac Function and N Terminal Pro BNP in Heart Failure

AIMS

The purpose of this study was to evaluate whether yoga training in addition to standard medical therapy can improve cardiac function and reduce N terminal pro B-type natriuretic peptide (NT pro BNP) in heart failure (HF).

METHODS

130 patients were recruited and randomized into two groups: Control Group (CG) (n = 65), Yoga Group (YG). In YG, 44 patients and in CG, 48 patients completed the study. Cardiac function using left ventricular ejection fraction (LVEF), myocardial performance index (Tei index), and NT pro BNP, a biomarker of HF, was assessed at baseline and after 12 weeks.

RESULT

Improvement in LVEF, Tei index, and NT pro BNP were statistically significant in both the groups. Furthermore, when the changes in before and after 12 weeks were in percentage, LVEF increased 36.88% in the YG and 16.9% in the CG, Tei index was reduced 27.87% in the YG and 2.79% in the CG, NT pro BNP was reduced 63.75% in the YG and 10.77% in the CG. The between group comparisons from pre to post 12 weeks were significant for YG improvements (LVEF, P < 0.01, Tei index, P < 0.01, NT pro BNP, P < 0.01).

CONCLUSION

These results indicate that the addition of yoga therapy to standard medical therapy for HF patients has a markedly better effect on cardiac function and reduced myocardial stress measured using NT pro BNP in patients with stable HF.

Old and new tools to assess dyspnea in the hospitalized patient

In the assessment of dyspnea one has to take into account both the patient's own experience of the symptom and the clinicians observations of breathing rates, sounds and effort to get a complete picture. In addition, to choose appropriate treatment, the underlying cause of dyspnea needs to be assessed. While tools for clinical evaluation of heart failure have gained great interest in research and found a place in guidelines and clinical practice, the same cannot be said for instruments to assess patient self-reported dyspnea. To date, no specific dyspnea rating tool has been recommend over another. Reports from clinical practice are lacking and large; international studies in this field are warranted.

Mechanisms of heart failure in obesity

Heart failure is a leading cause of morbidity and mortality and its prevalence continues to rise. Because obesity has been linked with heart failure, the increasing prevalence of obesity may presage further rise in heart failure in the future. Obesity-related factors are estimated to cause 11% of heart failure cases in men and 14% in women. Obesity may result in heart failure by inducing haemodynamic and myocardial changes that lead to cardiac dysfunction, or due to an increased predisposition to other heart failure risk factors. Direct cardiac lipotoxicity has been described where lipid accumulation in the heart results in cardiac dysfunction inexplicable of other heart failure risk factors. In this overview, we discussed various pathophysiological mechanisms that could lead to heart failure in obesity, including the molecular mechanisms underlying cardiac lipotoxicity. We defined the obesity paradox and enumerated various premises for the paradoxical associations observed in the relationship between obesity and heart failure.

Diagnostic and prognostic values of B-type natriuretic peptides (BNP) and N-terminal fragment brain natriuretic peptides (NT-pro-BNP)

B-type natriuretic peptide (BNP) is a member of a fournatriuretic peptide family that shares a common 17-peptide ring structure. The N-terminal fragment (NT-pro-BNP) is biologically inert, but both are secreted in the plasma in equimolar quantities and both have been evaluated for use in the management of congestive heart failure. BNP and NT-pro-BNP are frequently used in the diagnosis of congestive heart failure and distinguishing between patients with dyspnoea of cardiac or pulmonary origin. Values of NT-pro-BNP are affected by age or the presence of one or several co-morbidities such as chronic renal failure, type 2 diabetes, and acute coronary syndrome. 'Normal' values of these peptides also vary depending on the type of test used. The performance characteristics of these tests vary depending on the patients on whom they are used and the manufacturer. For this reason, the determination of reference values for this peptide represents such a challenge.

N-terminal prohormone B-type natriuretic peptide and weaning outcome in postoperative patients with pulmonary complications

Objective

To evaluate the relationship between plasma N-terminal prohormone B-type natriuretic peptide (NT-proBNP) and weaning outcomes, and the ability of NT-proBNP level to predict weaning success, in cancer patients with pulmonary complications undergoing noncardiac major surgeries.

Methods

Patients who were mechanically ventilated following postoperative respiratory failure were enrolled. NT-proBNP levels at the end of a 2-h spontaneous breathing trial were measured. Weaning was considered a success in patients who completed the trial and maintained spontaneous breathing following extubation for >48 h.

Results

Out of 29 patients, 22 patients weaned successfully but weaning failed in 7 patients. Plasma NT-proBNP was significantly higher in the weaning failure group than in the weaning success group. For predicting weaning success, the optimal NT-proBNP threshold value at the end of the spontaneous breathing trial was <448 ng/l (receiver operating characteristic analysis; sensitivity 68.18%, specificity 85.71%, positive predictive value 93.7% and negative predictive value 46.2%).

Conclusion

Measuring NT-proBNP at the end of a spontaneous breathing trial may assist in predicting weaning success, as a noninvasive, quantitative and repeatable indicator of cardiac stress in patients with postsurgical respiratory failure.

N-TproBNP as biomarker in systemic sclerosis

Systemic sclerosis (SSc) is a connective tissue disorder characterized by tissue fibrosis affecting the skin and internal organs, fibroproliferative vasculopathy, and autoimmune activation. SSc still heralds a poor prognosis with significant morbidity and mortality. Early detection of organ involvement is critical as currently available treatments are most effective when started early. Many candidate biomarkers have been investigated in the past two decades. However, despite the enormous efforts, no accurate tool to predict the pattern of organ involvement and to assess disease activity has been yet identified. The N-terminal fragment of probrain natriuretic peptide (N-TproBNP) is a neurohormone released by ventricular myocytes in response to pressure overload. N-TproBNP is highly relevant for diagnosis, prognosis, and prediction of pulmonary arterial hypertension in SSc. Moreover, several studies support its potential benefit for cardiac assessment of scleroderma patients. Conversely, the role of N-TproBNP as surrogate marker of pulmonary fibrosis and skin involvement is much less clear. We provide an extensive review of the studies that have previously investigated the role of N-TproBNP as candidate biomarker in scleroderma manifestations, presenting also the findings of a recent study we conducted in a cohort of 87 SSc patients.

Biomarkers of heart failure with normal ejection fraction: a systematic review

AIMS

Heart failure with normal ejection fraction (HFNEF) is a major and growing public health problem, currently representing half of the heart failure burden. Although many studies have investigated the diagnostic and prognostic value of new biomarkers in heart failure, limited data are available on biomarkers other than natriuretic peptides in HFNEF. We performed a systematic review of epidemiological studies on the associations of biomarkers with the occurrence of HFNEF and with the prognosis of HFNEF patients.

METHODS AND RESULTS

Biomarkers examined most extensively in HFNEF include biomarkers of myocyte stress, inflammation, and extracellular matrix remodelling. Some biomarkers have been shown to be increased to a different extent in HFNEF compared with heart failure with reduced ejection fraction (HFREF). Several biomarkers, including biomarkers of myocyte stress, inflammation, extracellular matrix remodelling, growth differentiation factor 15 (GDF-15), cystatin C, resistin, and galectin-3, were associated with development of HFNEF and with clinical outcomes of HFNEF patients in terms of morbidity and mortality.

CONCLUSION

Several biomarkers, including biomarkers of myocyte stress, inflammation, extracellular matrix remodelling, GDF-15, cystatin C, resistin, and galectin-3, appeared to be promising diagnostic and prognostic tools in patients with HFNEF. Investigation of the incremental diagnostic and prognostic value of these biomarkers, or a combination thereof, over established clinical covariates and imaging techniques in large, prospective studies is warranted.

Prognostic utility of B-type natriuretic peptides in patients with heart failure and renal dysfunction

Background

Renal dysfunction is considered a confounding variable in the interpretation of B-type natriuretic peptides (BNPs) and their amino-terminal fragments (NT-ProBNP) in patients with heart failure (HF). Our aim was to investigate the prognostic utility of BNPs and NT-proBNP in HF outpatients with renal dysfunction, and compare the prognostic significance of the corresponding BNP/NT-ProBNP levels in patients with and without renal dysfunction.

Methods

A total of 2076 patients from 13 HF clinics in the Norwegian Heart Failure Registry were investigated. The BNP/NT-ProBNP levels were categorized centre-wise into four groups using the quartile limits found in patients with preserved renal function. Patients with renal dysfunction, i.e. glomerular filtration rate (GFR) ≤60 mL/min/1.73 m², were then assigned to BNP groups 1–4 centre-wise according to their level of natriuretic peptides.

Results

Renal dysfunction was present in 37.5% of the patients, of whom the majority (59.1%) had levels of natriuretic peptide in the highest BNP group. Patients with renal dysfunction and BNP levels in the lower three BNP groups had similar 2-year survival as patients without renal dysfunction and comparable BNP levels [crude hazard ratio (HR) 1.25, 95% CI 0.82–1.89, P = 0.302, multiple adjusted HR 0.85, 95% CI 0.54–1.33, P = 0.457]. Beyond 2 years of follow-up, renal dysfunction predicted all-cause mortality irrespective of the level of natriuretic peptides at the start of follow-up.

Conclusion

In HF outpatients, the BNP/NT-ProBNP level predicted 2-year mortality irrespective of renal function and provided important prognostic information on patients with renal dysfunction.

HCV coinfection possibly promotes left ventricular dysfunction development: analysis of brain natriuretic peptide serum levels in HCV/HIV-coinfected and HIV-monoinfected patients

OBJECTIVE

Hepatitis C virus (HCV) has been already linked to possible myocarditis and cardiomyopathy development. The brain natriuretic peptide (BNP) is a sensitive biomarker of left ventricular dysfunction. The present study aimed to evaluate the potential risk of cardiac injury in HIV-infected and HCV/HIV-coinfected patients with or without antiretroviral (ARV) therapy by comparing BNP serum levels in the groups studied.

METHODS

Eighty HIV-infected patients (65 men, 15 women, mean age 40 years; 29 with HCV coinfection, 48 on combined ARV therapy) were included in the cross-sectional study. BNP serum levels were evaluated by enzyme-linked immunosorbent assay. The BNP cut-off level for possible heart failure was 42 fmol/l as in an immunocompetent population.

RESULTS

Seventy-eight (97.5%) patients studied had a BNP concentration above 42 fmol/l; seven patients (8.7%) had a concentration above 168 fmol/l associated with a worse outcome. There was no difference in the mean BNP serum levels in ARV-treated and untreated patients. However, the mean BNP serum level was significantly higher in HCV/HIV-coinfected patients in comparison with HIV-monoinfected patients (160.0 ± 130.9 vs. 81.9 ± 37.2 fmol/l; P<0.0001). There was no relationship between BNP serum levels and HIV viral load, CD4 cell count, sex, age, and abacavir or protease inhibitors use.

CONCLUSION

A significant association was found between HCV coinfection and BNP serum level in HIV-infected patients. HCV coinfection possibly enhances the risk of left ventricular dysfunction development in this vulnerable population.

Cystatin C in a composite risk score for mortality in patients with infective endocarditis: a cohort study

OBJECTIVE

To develop a multimarker prognostic score for infective endocarditis (IE).

DESIGN

Retrospective case-control.

SETTING

Secondary care. Single centre.

PARTICIPANTS

125 patients with definite IE.

PRIMARY OUTCOME MEASURES

90-day and 5-year mortality.

RESULTS

Mean age was 62.7±17 years. The 90-day and 5-year mortality was 10.4% and 33.6%, respectively. CysC levels at admission and over 20% increases in CysC levels during 2 weeks of treatment were prognostic for 90-day and 5-year mortality independent of creatinine estimated glomerular filtration rate. In multivariate analyses, CysC (OR 5.42, 95% CI 1.90 to 15.5, p=0.002) and age (OR 1.06, 95% CI 1.02 to 1.10, p=0.002) remained prognostic for 5-year mortality. NT-proBNP, TnT, C reactive protein and interleukin 6 were also linked to prognosis. A composite risk scoring system using levels of CysC, NT-proBNP, age and presence of mitral valve insufficiency was able to separate a high-risk and a low-risk group.

CONCLUSIONS

CysC levels at admission and increase in CysC after 2 weeks of treatment were independent prognostic markers for both 90-day and 5-year mortality in patients with IE. A multimarker composite risk scoring system including CysC identified a high-risk group.

Acute study of clinical effectiveness of nesiritide in decompensated heart failure: nesiritide redux

Nesiritide, a synthetic drug form of human B-type natriuretic peptide, is approved for the early treatment of dyspnea in acute decompensated heart failure. Meta-analyses suggested a risk of worsening renal insufficiency and mortality with its use. Therefore, the Acute Study of Clinical Effectiveness in Decompensated Heart Failure (ASCEND-HF) was designed as a prospective, multicenter, double-blind, randomized trial to examine the use of nesiritide in this common, morbid, and often lethal clinical condition. Two coprimary end points, dyspnea and 30-day hospital readmission or death, were chosen to examine symptomatic response and objective outcomes, respectively. Preliminary reports from ASCEND-HF investigators suggest no significant improvement in symptoms or clinical outcomes, although no adverse effect on mortality or renal function was noted. We recommend the continued use of nesiritide in acute decompensated heart failure as an individualized case-based therapy to those patients who meet criteria for treatment and are expected to receive benefit from its use.

Clinical Use of Natriuretic Peptides

Either B-type natriuretic peptide (BNP) or NT-proBNP may be used as a diagnostic, screening, prognostic and therapeutic tool for CHF. The Food and Drug Administration (FDA) cleared the cut-off point for BNP at 100 pg/mL, and that of NT-proBNP at 125 pg/mL for patients <75 years and 450 pg/mL for those >75. A steadily rising titre even below the cut-off value should be raised as a concern as heart failure is progressive if left untreated and may result in cardiac death. Both biomarkers are also featured in lab investigations for patients with acute coronary syndrome (ACS).

Relationship Between MMP-1, MMP-9, TIMP-1, IL-6 and Risk Factors, Clinical Presentation, Extent and Severity of Atherosclerotic Coronary Artery Disease

Background:

Matrix metalloproteinases (MMPs) and Tissue Inhibitor of Matrix Metalloproteinases (TIMPs) may be associated with atherogenesis and plaque rupture. We evaluated the relationship between MMP-1, MMP-9, TIMP-1 and IL-6 levels and risk factors, presentation, extent and severity of atherosclerotic coronary artery disease (CAD).

Methods:

Consecutive patients who underwent coronary angiography were randomly included. The serum concentrations of MMP-1, MMP-9, TIMP-1 and IL-6 were analyzed with ELISA method in 134 patients. Participants were divided into 5 groups; stable angina pectoris (SAP; n= 34), unstable angina pectoris (USAP; n=29), non-ST elevation myocardial infarction (NSTEMI; n=16), acute ST elevation myocardial infarction (STEMI; n=25) and controls (n=30). Coronary angiographic Gensini score was calculated.

Results:

MMP-1 levels were higher in STEMI and NSTEMI groups compared with USAP, SAP and control groups (STEMI vs USAP p=0.005; STEMI vs SAP p=0.001; STEMI vs control p<0.001; NSTEMI vs USAP p=0.02; NSTEMI vs SAP p=0.027; NSTEMI vs control p<0.001). In STEMI group, MMP-9 levels were higher than USAP and control groups (p=0.002; p<0,001). TIMP-1 levels were not significantly different within all 5 groups. MMP-1 levels were found to be elevated in diabetic patients (p=0.020); whereas MMP-9 levels were higher in smokers (p=0.043). Higher MMP-1, MMP-9 and IL-6 levels were correlated with severe Left Anterior Descending artery (LAD) stenosis and higher angiographic Gensini Score (for severe LAD stenosis; r = 0.671, 0.363, 0.509 p<0.001; for Gensini score; r = 0.717, 0.371, 0.578 p<0.001).

Conclusions:

Serum levels of MMP-1, MMP-9, and IL-6 are elevated in patients with CAD; more so in acute coronary syndromes. MMP-1, MMP-9 and IL-6 are associated with more extensive and severe CAD (as represented by Gensini score).

The causes, consequences, and treatment of left or right heart failure

Chronic heart failure (HF) is a cardiovascular disease of cardinal importance because of several factors: a) an increasing occurrence due to the aging of the population, primary and secondary prevention of cardiovascular events, and modern advances in therapy, b) a bad prognosis: around 65% of patients are dead within 5 years of diagnosis, c) a high economic cost: HF accounts for 1% to 2% of total health care expenditure. This review focuses on the main causes, consequences in terms of morbidity, mortality and costs and treatment of HF.

Cardio-metabolic risk prediction should be superior to cardiovascular risk assessment in primary prevention of cardiovascular diseases

Cardiovascular atherosclerotic diseases represent the main cause of death in the developed and developing populations. Although major progress has been made in the management of the classical modifiable cardiovascular risk factors, unhealthy lifestyle conduces to an increasing prevalence of overweight, obesity, metabolic disorders, type 2 diabetes mellitus, premature atherosclerosis and cardiovascular diseases. That is why cardio-metabolic risk prediction should be superior in the primary prevention of atherosclerosis and cardiovascular diseases. Up-to-date primary preventive strategies according to the European Guidelines, especially the high risk strategy approach, are being implemented. Individual cardiovascular and better cardio-metabolic risk assessment represents the basic approach in the individualized primary prevention of cardiovascular diseases and type 2 diabetes mellitus. Cardio-metabolic biomarkers, especially high sensitivity C-reactive protein, albuminuria, N-terminal pro-brain natriuretic peptide, and imaging procedures (carotid intima-media thickness measured by ultrasound) could improve the prediction of cardiovascular diseases and type 2 diabetes beyond that using traditional risk factors.

Associations between cardiovascular parameters and uteroplacental Doppler (blood) flow patterns during pregnancy in women with congenital heart disease: Rationale and design of the Zwangerschap bij Aangeboren Hartafwijking (ZAHARA) II study

BACKGROUND

Previous research has shown that women with congenital heart disease (CHD) are more susceptible to cardiovascular, obstetric, and offspring events. The causative pathophysiologic mechanisms are incompletely understood. Inadequate uteroplacental circulation is an important denominator in adverse obstetric events and offspring outcome. The relation between cardiac function and uteroplacental perfusion has not been investigated in women with CHD. Moreover, the effects of physiologic changes on pregnancy-related events are unknown. In addition, long-term effects of pregnancy on cardiac function and exercise capacity are scarce.

METHODS

Zwangerschap bij Aangeboren Hartafwijking (ZAHARA) II, a prospective multicenter cohort study, investigates changes in and relations between cardiovascular parameters and uteroplacental Doppler flow patterns during pregnancy in women with CHD compared to matched healthy controls. The relation between cardiovascular parameters and uteroplacental Doppler flow patterns and the occurrence of cardiac, obstetric, and offspring events will be investigated. At 20 and 32 weeks of gestation, clinical, neurohumoral, and echocardiographic evaluation and fetal growth together with Doppler flow measurements in fetal and maternal circulation are performed. Maternal evaluation is repeated 1 year postpartum.

IMPLICATIONS

By identifying the factors responsible for pregnancy-related events in women with CHD, risk stratification can be refined, which may lead to better pre-pregnancy counseling and eventually improve treatment of these women.

Cardiomyocyte-specific prolyl-4-hydroxylase domain 2 knock out protects from acute myocardial ischemic injury

Prolylhydroxylase domain proteins (PHD) are cellular oxygen-sensing molecules that regulate the stability of the α-subunit of the transcription factor hypoxia inducible factor (HIF)-1. HIF-1 affects cardiac development as well as adaptation of the heart toward increased pressure overload or myocardial infarction. We have disrupted PHD2 in cardiomyocytes (cPhd (-/-)) using Phd2(flox/flox) mice in combination with MLCvCre mice, which resulted in HIF-1α stabilization and activation of HIF target genes in the heart. Although cPhd2(-/-) mice showed no gross abnormalities in cardiac filament structure or function, we observed a significant increased cardiac capillary area in those mice. cPhd2 (-/-) mice did not respond differently to increased mechanical load by transverse aortic constriction compared with their wild-type (wt) littermates. After ligation of the left anterior descending artery, however, the area at risk and area of necrosis were significantly smaller in the cPhd2(-/-) mice compared with Phd2 wt mice in line with the described pivotal role of HIF-1α for tissue protection in case of myocardial infarction. This correlated with a decreased number of apoptotic cells in the infarcted myocardium in the cPhd2(-/-) mice and significantly improved cardiac function 3 weeks after myocardial infarction.