The influence of age, sex and other variables on the plasma level of N-terminal pro brain natriuretic peptide in a large sample of the general population

Growth differentiation factor-15 combined with N-terminal prohormone of brain natriuretic peptide increase 1-year prognosis prediction value for patients with acute heart failure: a prospective cohort study

BACKGROUND

Clinical assessment and treatment guidance for heart failure depends on a variety of biomarkers. The objective of this study was to investigate the prognostic predictive value of growth differentiation factor-15 (GDF-15) and N-terminal prohormone of brain natriuretic peptide (NT-proBNP) in assessing hospitalized patients with acute heart failure (AHF).

METHODS

In total, 260 patients who were admitted for AHF in the First Affiliated Hospital of Nanjing Medical University were enrolled from April 2012 to May 2016. Medical history and blood samples were collected within 24 h after the admission. The primary endpoint was the all-cause mortality within 1 year. The patients were divided into survival group and death group based on the endpoint. With established mortality risk factors and serum GDF-15 level, receiver-operator characteristic (ROC) analyses were performed. Cox regression analyses were used to further analyze the combination values of NT-proBNP and GDF-15.

RESULTS

Baseline GDF-15 and NT-proBNP were significantly higher amongst deceased than those in survivors (P < 0.001). In ROC analyses, area under curve (AUC) for GDF-15 to predict 1-year mortality was 0.707 (95% confidence interval [CI]: 0.648-0.762, P < 0.001), and for NT-proBNP was 0.682 (95% CI: 0.622-0.738, P < 0.001). No statistically significant difference was found between the two markers (P = 0.650). Based on the optimal cut-offs (GDF-15: 4526.0 ng/L; NT-proBNP: 1978.0 ng/L), the combination of GDF-15 and NT-proBNP increased AUC for 1-year mortality prediction (AUC = 0.743, 95% CI: 0.685-0.795, P < 0.001).

CONCLUSIONS

GDF-15, as a prognostic marker in patients with AHF, is not inferior to NT-proBNP. Combining the two markers could provide an early recognition of high-risk patients and improve the prediction values of AHF long-term prognosis.

CLINICAL TRIAL REGISTRATION

ChiCTR-ONC-12001944, http://www.chictr.org.cn.

Racial differences in the association of NT-proBNP with risk of incident heart failure in REGARDS

BACKGROUND

Black individuals have lower natriuretic peptide levels and greater risk of heart failure (HF) than white individuals. Higher N-terminal-pro-B-type natriuretic peptide (NT-proBNP) is associated with increased risk of incident HF, but little information is available in black individuals. We examined race-specific differences in 1) the association of NT-proBNP with incident HF and 2) the predictive ability of NT-proBNP for incident HF across body mass index (BMI) and estimated glomerular filtration rate (eGFR) categories.

METHODS

In a prospective case-cohort study, baseline NT-proBNP was measured among 687 participants with incident HF and 2,923 (weighted 20,075) non-case randomly selected participants. Multivariable Cox proportional hazard modeling was used to assess the objectives of our study. Global Wald Chi-square score estimated from multivariable Cox models was used to assess predictive ability of NT-proBNP across BMI and eGFR categories.

RESULTS

In the multivariable model, a doubling of NT-proBNP concentration was associated with greater risk of incident HF among white individuals [hazard ratio (HR): 1.73; 95% CI: 1.55-1.94] than black individuals (HR: 1.51; 95% CI: 1.34-1.70); Pinteraction by race = 0.024. Higher NT-proBNP was the strongest predictor of incident HF across all BMI and eGFR categories among white individuals. By contrast, among black individuals with obesity (BMI ≥ 30 kg/m2) or eGFR < 60 mL/min/1.73 m2, the predictive ability of NT-proBNP for incident HF was attenuated.

CONCLUSIONS

The magnitude of the association of higher NT-proBNP with incident HF risk was greater among white individuals than black individuals. The diminished ability of NT-proBNP to predict the risk of HF in black population with obesity or impaired kidney function highlights the need of further investigations.

Characterisation of N-terminal pro-brain natriuretic peptide in dialysis patients and its reduced prognostic significance in the elderly

Characterisation of N-terminal pro-brain natriuretic peptide (NT-proBNP) in chronic haemodialysis patients and its prognostic significance in age stratification have not been addressed. A prospective cohort study with cross-sectional analyses at baseline was performed. Outcomes were all-cause mortality, non-malignancy-related mortality, and cardiovascular disease (CVD)-related mortality. NT-proBNP was significantly higher in elderly, female, and low dry weight patients. Study patients were divided into two groups: Group-O (≥75 years) and Group-Y (<75 years). The 7-year follow-up receiver operating curve analysis showed that NT-proBNP significantly predicted all outcomes. All-cause mortality cut-off points were significantly different among the groups (total cohort, 5375 pg/mL; Group-Y, 3682 pg/mL; Group-O, 11750 pg/mL). Cox regression analysis showed risks for all outcomes by tertile NT-proBNP significantly higher in the total cohort and Group-Y as adjusted by potential confounders. For all-cause mortality, hazard ratios and 95% confidence intervals (CI) were T2 1.70 (0.89 to 3.25), p = 0.11, T3 2.95 (1.54 to 5.67), p < 0.01 in Group-Y; and T2 1.00 (0.64 to 1.58), p = 1.00; T3 1.50 (0.94 to 2.40), p = 0.09 in Group-O. In conclusion, NT-proBNP was significantly higher in elderly, female, and low dry weight chronic dialysis patients. NT-proBNP was significantly associated with all outcomes. However, this association was reduced in elderly patients.

Race-based demographic, anthropometric and clinical correlates of N-terminal-pro B-type natriuretic peptide

BACKGROUND

Population studies have shown that black race is a natriuretic peptide (NP) deficiency state. We sought to assess whether the effects of age, sex, body mass index (BMI) and estimated glomerular filtration rate (eGFR) on N-terminal-pro-B-type NP (NT-proBNP) levels differ in white and black individuals.

METHODS

The study population consisted of a stratified random cohort from the REasons for Geographic And Racial Differences in Stroke (REGARDS) study. The study outcomes were the effects of age, sex, BMI and eGFR on NT-proBNP levels independent of socioeconomic and cardiovascular disease factors. Multivariable regression analyses were used to assess the effects of age, sex, BMI and eGFR on NT-proBNP levels in blacks and whites.

RESULTS

Of the 27,679 participants in the weighted sample, 54.7% were females, 40.6% were black, and the median age was 64 years. Every 10-year higher age was associated with 38% [95% confidence interval (CI): 30%-45%] and 34% (95% CI: 22%-43%) higher NT-proBNP levels in whites and blacks, respectively. Female sex was associated with 31% (95% CI: 20%-43%) higher NT-proBNP levels in whites and 28% (95% CI: 15%-45%) higher in blacks. There was a significant linear inverse relationship between BMI and NT-proBNP in whites and a non-linear inverse relationship in blacks. Whites and blacks had a non-linear inverse relationship between eGFR and NT-proBNP. However, the non-linear relationship between NT-proBNP and eGFR differed by race (p = 0.01 for interaction).

CONCLUSIONS

The association of age and sex with NT-proBNP levels was similar in blacks and whites but the form of the BMI and eGFR relationship differed by race.

SOMAscan-based proteomic measurements of plasma brain natriuretic peptide are decreased in mild cognitive impairment and in Alzheimer's dementia patients

Alzheimer's disease represents the most common age-related neurodegenerative disorder and a leading cause of progressive cognitive impairment. Predicting cognitive decline is challenging but would be invaluable in an increasingly aging population which also experiences a rising cardiovascular risk. In order to examine whether plasma measurements of one of the established biomarkers of heart failure, brain natriuretic peptide (BNP), reflect a decline in cognitive function, associated with Alzheimer's disease neurodegeneration, BNP levels were analysed, by using a novel assay called a SOMAscan, in 1. cognitively healthy, control subjects; 2. subjects with mild cognitive impairment, and 3. subjects with Alzheimer's disease. The results of our study show that the levels of the BNP were significantly different between the three types of diagnoses (p < 0.05), whereby subjects with mild cognitive impairment had the lowest mean BNP value, and healthy subjects had the highest BNP value. Importantly, our results show that the levels of the BNP are influenced by the presence of at least one APOE4 allele in the healthy (p < 0.05) and in the Alzheimer's disease groups of subjects (p < 0.1). As the levels of the BNP appear to be independent of the APOE4 genotype in subjects with mild cognitive impairment, the results of our study support inclusion of measurements of plasma levels of the BNP in the list of the core Alzheimer's disease biomarkers for identification of the mild cognitive impairment group of patients. In addition, the results of our study warrant further investigations into molecular links between Alzheimer's disease-type cognitive decline and cardiovascular disorders.

N-terminal-pro-b-type natriuretic peptide levels and cardiac hemosiderosis in adolescent β-thalassemia major patients

Background:

Iron-induced cardiomyopathy remains the leading cause of mortality in patients with β-thalassemia major. Iron overload cardiomyopathy, which may be reversible through iron chelation, is characterized by early diastolic dysfunction. Amino-terminal pro-brain natriuretic peptide (NT-proBNP) is a sensitive biomarker of diastolic dysfunction.

Aim:

The aim of the study is to evaluate the diagnostic value of NT-proBNP as a surrogate marker of iron overload examined with magnetic resonance imaging T2-star (MRI T2*).

Methods:

Sixty-eight β-thalassemia major patients (10–18 years) with no signs of heart failure underwent NT-proBNP measurement before routine transfusion. All participants prospectively underwent cardiac MRI T2* examination within 3 months (median 19 days). Patients were divided as cardiac hemosiderosis (cardiac MRI T2* <20 ms) and nonhemosiderosis (cardiac MRI T2* >20 ms).

Results:

Of 68 patients, the male-to-female ratio was 1:1.1 and the median age was 14.1 years (range: 10–17.8 years). NT-proBNP levels were not different between hemosiderosis and nonhemosiderosis patients (P = 0.233). Further receiver operating characteristic analysis resulted in no significant correlation of NT-proBNP and MRI T2* (area under the curve 0.393, P = 0.233).

Conclusion:

Measurement of NT-proBNP levels cannot be used for early detection of cardiac iron overload in adolescent with β-thalassemia major.

Sex-Specific Cut-Offs for High-Sensitivity Cardiac Troponin: Is Less More?

Management of patients presenting to the Emergency Department with chest pain is continuously evolving. In the setting of acute coronary syndrome, the availability of high-sensitivity cardiac troponin assays (hs-cTn) has allowed for the development of algorithms aimed at rapidly assessing the risk of an ongoing myocardial infarction. However, concerns were raised about the massive application of such a simplified approach to heterogeneous real-world populations. As a result, there is a potential risk of underdiagnosis in several clusters of patients, including women, for whom a lower threshold for hs-cTn was suggested to be more appropriate. Implementation in clinical practice of sex-tailored cut-off values for hs-cTn represents a hot topic due to the need to reduce inequality and improve diagnostic performance in females. The aim of this review is to summarize current evidence on sex-specific cut-off values of hs-cTn and their application and usefulness in clinical practice. We also offer an extensive overview of thresholds reported in literature and of the mechanisms underlying such differences among sexes, suggesting possible explanations about debated issues.

N-terminal pro-brain natriuretic peptide reflects both left ventricular diastolic dysfunction and myeloma-related renal insufficiency and robustly predicts mortality in patients with symptomatic multiple myeloma

We retrospectively explored the prognostic relevance of N-terminal pro-brain natriuretic peptide (NT-proBNP) and the association of NT-proBNP with cardiac and renal functions in 153 patients with newly diagnosed symptomatic multiple myeloma and no concomitant light chain amyloidosis who received novel agents. We also examined the usefulness of the new frailty system recently introduced by Mayo Clinic (combining age, performance status, and NT-proBNP). Patients with higher NT-proBNP levels (≥300 ng/L) had a significantly higher incidence of left ventricular diastolic dysfunction (LVDD) and myeloma-related renal insufficiency and significantly shorter overall survival (OS) than did those with lower NT-proBNP levels (<300 ng/L). NT-proBNP remained predictive of OS on multivariate analysis. Mayo Clinic's new frailty system showed excellent discrimination of OS. Furthermore, the Instrumental Activity of Daily Living (IADL) score (not evaluated in Mayo Clinic's study) predicted OS independently of this system, and a sharper discrimination of OS curves was obtained by the incorporation of IADL into this system. Our findings demonstrated that NT-proBNP levels were associated with both LVDD (as a host risk factor) and myeloma-related renal insufficiency (resulting from the disease aggressiveness) and provided predictive information regarding OS in patients with symptomatic myeloma. Furthermore, we, for the first time, validated Mayo Clinic's new frailty system. Our modification further improved Mayo Clinic's system by newly incorporating the IADL score.

Can Admission BNP Level Predict Outcome After Intravenous Thrombolysis in Acute Ischemic Stroke?

OBJECTIVE

Our study aimed to determine the prognostic value of elevated Brain Natriuretic Peptide (BNP) among patients who received intravenous thrombolysis (IVT) in acute ischemic stroke (AIS).

BACKGROUND

The elevation in BNP level is correlated with infarct size, poststroke mortality, and CHADS2 score. Currently, there is a lack of validated biomarker to predict the outcome in patients with acute ischemic stroke, and there is a complex interaction amongst multiple variables.

DESIGN/METHODS

A retrospective review of medical records of patients admitted to our institution with acute ischemic stroke was performed. The patients who received intravenous thrombolysis were selected for analysis and divided into 2 groups based on the level of BNP. We compared the baseline demographics, past medical history, stroke etiology, discharge disposition, and 3-month mRS between both groups. Multivariate logistic regression analysis was performed to identify the predictors of poor outcome following intravenous thrombolysis in acute ischemic stroke.

RESULTS

A total of 90 patients were recruited in the study; 53 patients were found to have an elevated BNP (high BNP was defined as >100 pg/mL) level, whereas 37 had low BNP levels. Our study showed that patients with elevated BNP were more likely to have an elevation in admission and discharge NIHSS, serum creatinine, left atrial size, and blood glucose (P<0.05). Atrial fibrillation and cardioembolic strokes were seen most often in the population with elevated BNP (P<0.05). The patients with elevated BNP were less likely to be discharged home, and 3-month mRS was found to be higher, but these were not significant. On multivariate analysis, elevated BNP was not found to be an independent factor for poor outcome.

CONCLUSIONS

Elevated BNP level was not found to be an independent marker of poor outcome in AIS patients following IVT.

ADMA and NT pro-BNP are associated with overall mortality in elderly

BACKGROUND

Increased asymmetrical dimethylarginine (ADMA) and NT pro-BNP concentrations have been associated with mortality in patients with cardiovascular (CV) disease and the general population. The use of these prognostic markers in an older population is not established yet. The aim of the present study was to investigate the prognostic value of age, sex, BMI, co-medication and CV laboratory risk markers in geriatric care patients.

MATERIALS AND METHODS

In this prospective observational single-centre cohort study data of long-term geriatric care patients were collected. Blood samples were collected between 14.09.2009 and 16.12.2009, and mortality was recorded up to 90 months. ADMA, its symmetric isomer SDMA, L-arginine, NT pro-BNP and CRP were determined at study entry. Simple associations of risk factors for survival period were explored by Spearman correlation coefficient. Significant univariate predictors for survival period were used in the Cox proportional hazard model.

RESULTS

A total of 481 patients were screened, and data from 449 patients were analysed. A total of 381 patients died during the observation period. Full data sets from 344 patients were used for Cox regression analysis. Male sex, older age, lower BMI, use of neuroleptic medicine, peripheral artery disease, and elevated plasma concentrations of ADMA, NT pro-BNP, and CRP were significant predictors of mortality.

CONCLUSION

The concentration of ADMA and NT pro-BNP may be used as an early risk marker for overall mortality in geriatric care. Neuroleptic medicine is associated with increased mortality in this population.

Comparison of the Diagnostic Accuracy of Plasma N-Terminal Pro-Brain Natriuretic Peptide in Patients <80 to those >80 Years of Age with Heart Failure

Plasma N-Terminal Pro-Brain Natriuretic Peptide (NTproBNP) is known to increase with age, however, the performance of this biomaker is unclear in patients >80. This study sought to define the diagnostic accuracy of plasma NTproBNP in patients >80 in a large unselected population of heart failure (HF) patients admitted to a Tertiary Hospital in the United Kingdom. 1,995 consecutive patients over a 12 month period were screened for HF through our NTproBNP led HF service. 413 patients had their first presentation of HF and 36.1% of these patients were >80. There was a reduction in accuracy of NTproBNP with age according to the area under the curve, with an area under the curve for all HF patients of 0.734 and a 7.5% reduction in receiver operating characteristic curve area for patients >80 years compared with those under 60 to 79 years of age. The lowest NTproBNP recorded for patients with HF >80 years of age was 466 pg/ml. In HF patients >80, 40.6% patients were diagnosed with HFrEF, 31.1% with HFpEF and 28.2% with HFmrEF. Overall NTproBNP is less accurate at identifying HF in patients >80 years of age and the lowest NTproBNP recorded for a HF patient was 466 pg/ml suggesting that the NTproBNP threshold for ruling out HF in patients >80 years of age should be modified.

Value of cardiac biomarker measurement in the differential diagnosis of infiltrative cardiomyopathy patients with preserved left ventricular systolic function

Background

This study aimed to explore the value of cardiac biomarker [serum high sensitive troponin T (hs-TNT) and N-terminal pro-brain natriuretic peptide (NT-proBNP)] measurement in the differential diagnosis of infiltrative cardiomyopathy patients [Friedreich's ataxia (FA), Fabry disease (FD) and light-chain (AL) cardiac amyloidosis (CA)] with preserved left ventricular (LV) systolic function.

Methods

Between 2012 and 2014, all consecutive patients presenting at our center with infiltrative cardiomyopathy and concomitant symmetrical LV hypertrophy as well as preserved LV systolic function were included in this study. Serum hs-TNT and NT-proBNP, morphologic and functional features derived from echocardiography and cardiac magnetic resonance imaging (cMRI) examinations were compared among these patients.

Results

A total of 57 patients (FA 20, FD 23 and CA 14) were included. Hs-TNT and NT-proBNP levels were significantly higher in the CA group [median: hs-TNT 98 pg/mL, NT-proBNP 4,110 pg/mL] than in the FA group [hs-TNT 14 pg/mL, NT-proBNP 40 pg/mL] and FD group [hs-TNT 18 pg/mL, NT-proBNP 131 pg/mL, both P<0.001]. There was a negative correlation between NT-proBNP and estimated glomerular filtration rate (eGFR) in CA patients (r=-0.72, P=0.012). Both hs-TNT >60 pg/mL (sensitivity 0.79, specificity 0.93) and NT-proBNP >1,000 pg/mL (sensitivity 0.91, specificity 0.93) excellently differentiated CA from FA and FD.

Conclusions

Increased hs-TNT and NT-proBNP levels are suggestive of CA diagnosis among patients with infiltrative cardiomyopathy and preserved LV ejection fraction.

Sex Differences in the Prognostic Power of Brain Natriuretic Peptide and N-Terminal Pro-Brain Natriuretic Peptide for Cardiovascular Events - The Japan Morning Surge-Home Blood Pressure Study

BACKGROUND

Brain natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) are prognostic biomarkers. Although these 2 peptides differ with regard to biological characteristics, there are few reports on the differences between BNP and NT-proBNP with regard to cardiovascular events or according to sex.Methods and Results:Between 2005 and 2012, this study analyzed 3,610 of 4,310 Japanese outpatients (mean age, 65 years; men, n=1,664; women, n=1,947) with a history of at least one cardiovascular event who were recruited to the Japan Morning Surge-Home Blood Pressure Study. During an average 4-year follow-up, there were 129 cardiovascular events. Both median BNP (21.1 pg/mL; IQR, 10.9-40.6 pg/mL vs. 16.2 pg/mL, IQR, 7.2-36.2 pg/mL, P<0.001) and median NT-proBNP (54.7 pg/mL; IQR, 30.2-102.6 pg/mL vs. 44.9 pg/mL, IQR, 20.7-92.6 pg/mL, P<0.001) were significantly higher in women than in men. A 1-SD increment in log-transformed BNP (hazard ratio [HR], 2.18; 95% CI: 1.53-3.10) and NT-proBNP (HR, 2.39; 95% CI: 1.73-3.31) was associated with a significant increase in cardiovascular events in women; in men, only NT-proBNP showed this association. There was an interaction between log-transformed BNP (P=0.007) or NT-proBNP (P=0.001) and cardiovascular events according to sex.

CONCLUSIONS

Both BNP and NT-proBNP predicted cardiovascular outcomes in a large Japanese clinical population. BNP and NT-proBNP were significantly stronger predictors in women than in men.

Sex-specific associations of obesity and N-terminal pro-B-type natriuretic peptide levels in the general population

BACKGROUND

Obese subjects have lower natriuretic peptide levels, but males and females have different anthropometric characteristics and fat distribution. Whether obesity-associated lowering of natriuretic peptides differs among males and females is unknown. Therefore, we investigated sex-specific associations of obesity and N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels among adults in the general population.

METHODS AND RESULTS

Using 8260 participants (50.1% females) from the Prevention of REnal and Vascular ENd-stage Disease (PREVEND) cohort, we evaluated the relationship of NT-proBNP levels with obesity-associated parameters, i.e. waist circumference (WC), body mass index (BMI) and body weight in the overall population, and in males and females separately. NT-proBNP levels were higher in females (median, interquartile range: 50.5, 28.2-87.0 ng/L) than in males (24.3, 10.1-54.6 ng/L; P < 0.001). In the overall population, NT-proBNP levels were significantly lower in heavier individuals and displayed a 'U-shaped' relationship with increasing WC, but were not associated with BMI. After sex stratification, there was no significant association between NT-proBNP concentrations and anthropometric measures in females. However, in males increasing WC and BMI were associated with higher NT-proBNP levels (P < 0.05) while increasing body weight was associated with slightly lower NT-proBNP levels (P < 0.05). Age strongly confounded the association of NT-proBNP levels with obesity, and age-associated increases in NT-proBNP were significantly higher in males than in females (P < 0.001). In multivariable adjusted analyses, the inverse association of obesity and NT-proBNP levels was also significantly modified by sex: NT-proBNP levels were lower with increasing WC, BMI and body weight among females compared with males (P_interaction  < 0.05). After also accounting for BMI, abdominal obesity was associated with lower NT-proBNP levels in females, but not in males (P_interaction  < 0.001).

CONCLUSIONS

Natriuretic peptide deficiency in obesity mostly pertains to females with abdominal obesity, whereas the relationship between obesity and natriuretic peptides appears to be more complex in males.

Addition of N-terminal pro-B natriuretic peptide to soluble fms-like tyrosine kinase-1/placental growth factor ratio > 38 improves prediction of pre-eclampsia requiring delivery within 1 week: a longitudinal cohort study

OBJECTIVE

Short-term prediction of pre-eclampsia (PE) using the soluble fms-like tyrosine kinase-1 (sFlt-1)/placental growth factor (PlGF) ratio is characterized by frequent false-positive results. As such, no treatment can be recommended to test-positive patients and multiple measurements are often required. The aim of this study was to evaluate the effectiveness of N-terminal pro-B natriuretic peptide (NT-proBNP), uric acid and the sFlt-1/PlGF ratio for prediction of delivery with PE within 1 week in singleton pregnancies with suspected PE and sFlt-1/PlGF ratio > 38.

METHODS

This was a longitudinal prospective cohort study of singleton pregnancies presenting at 24 + 0 to 36 + 6 weeks of gestation with clinically suspected PE and sFlt-1/PlGF ratio > 38, enrolled between January 2015 and June 2017. Multiple samples per patient were allowed but were restricted to one sample per gestational week. From 495 enrolled patients, 270 blood samples from 134 patients were ultimately analyzed. By using generalized estimating equations (GEE), the best-fit model was selected for prediction of delivery with PE within 1 week. The predictive value of this model was then assessed using area under the paired-ROC curve (AUC) analysis.

RESULTS

The best-fit model included the sFlt-1/PlGF ratio, NT-proBNP and the gestational week at the time of the measurement. This combined model was compared with the GEE model based on the sFlt-1/PlGF ratio and the gestational week at the time of the measurement (reduced model). The AUC for the combined model was 0.845 (95% CI, 0.787-0.896), which was significantly greater (P = 0.011) than that of the reduced model (0.786 (95% CI, 0.722-0.844)).

CONCLUSION

The addition of NT-proBNP assessment improves the short-term prediction of delivery as a result of PE compared with sFlt-1/PlGF ratio alone, when the sFlt-1/PlGF ratio is > 38. This finding should be considered in future research on the assessment of short-term risk of delivery as a result of PE. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Does natriuretic peptide monitoring improve outcomes in heart failure patients? A systematic review and meta-analysis

BACKGROUND

Current guidelines do not support the use of serial natriuretic peptide (NP) monitoring for heart failure with preserved (HFpEF) or reduced ejection fraction (HFrEF) treatment, despite some studies showing benefit. We conducted an updated meta-analysis to address whether medical therapy in HFpEF or HFrEF should be titrated according to NP levels.

METHODS

MEDLINE, Scopus and Cochrane CENTRAL databases were searched for randomized controlled trials (RCTs) comparing NP versus guideline directed titration in HF patients through December 2017. The key outcomes of interest were mortality, HF hospitalizations and all-cause hospitalizations. Risk ratios and 95% confidence intervals were pooled using random effects model. Sub-group analyses were performed for type of NP used, average age and acute or chronic HF.

RESULTS

Eighteen trials including 5116 patients were included. Meta-analysis showed no significant difference between the NP-guided arm versus guideline directed titration in all-cause mortality (RR = 0.91 [0.81, 1.03]; p = 0.13), HF hospitalizations (RR = 0.81 [0.65, 1.01]; p = 0.06), and all cause hospitalizations (RR = 0.93 [0.86, 1.01]; p = 0.09). The results were consistent upon subgroup analysis by biomarker type (NT-proBNP or BNP) and type of heart failure (acute or chronic and HFrEF or HFpEF). Sub-group analysis suggested that NP-guided treatment was associated with decreased all-cause hospitalizations in patients younger than 72 years of age.

CONCLUSION

The available evidence suggests that NP-guided therapy provides no additional benefit over guideline directed therapy in terms of all-cause mortality and HF-related hospitalizations in acute or chronic HF patients, regardless of their ejection fraction.

Early Cardiotoxicity after Adjuvant Concomitant Treatment with Radiotherapy and Trastuzumab in Patients with Breast Cancer

Background

The purpose of the study was to find out whether there is a difference in the early parameters of cardiotoxicity (left ventricular ejection fraction [LVEF] and N-terminal pro-B-type natriuretic peptide [NT-proBNP]) between the two groups of patients: the patients treated for left breast cancer (left breast cancer group) and those treated for the right breast cancer (right breast cancer group), after the treatment had been completed.

Patients and methods

The study included 175 consecutive patients with human epidermal growth factor receptor-2 (HER2) positive early breast cancer, treated concurrently with trastuzumab and radiotherapy (RT), between June 2005 and December 2010. Echocardiography with LVEF measurement was performed before adjuvant RT (LVEF₀) and after the completed treatment (LVEF₁,). After the treatment NT-proBNP measurement was done as well. The difference (Δ) between LVEF₀ and LVEF₁ was analysed (Δ LVEF = LVEF₀ - LVEF₁) and compared between the two groups.

Results

There were 84 patients in the left and 91 in the right breast cancer group. Median observation time was 57 (37–71) months. Mean Δ LVEF (%) was -1.786% in the left and -2.607% in the right breast cancer group (p = 0.562, CI: -2.004 to 3.648). Median NT-proBNP were 111.0 ng/l in the left and 90.0 ng/l in the right breast cancer group (p = 0.545). Echocardiography showed that the patients in the left breast cancer group did not have significantly worse systolic and diastolic left ventricular function in comparison with the patients in the right breast cancer group, but, they had higher incidence of pericardial effusion (9 [11%] vs. 1 [1%]) (p = 0.007).

Conclusions

We did not find any significant differences in the early parameters of cardiotoxicity (LVEF, NT-proBNP) between the observed groups. Patients who received left breast/chest wall irradiation had higher incidence of pericardial effusion.

Interaction of Body Mass Index on the Association Between N-Terminal-Pro-b-Type Natriuretic Peptide and Morbidity and Mortality in Patients With Acute Heart Failure: Findings From ASCEND-HF (Acute Study of Clinical Effectiveness of Nesiritide in Decompensated Heart Failure)

BACKGROUND

Higher body mass index (BMI) is associated with lower circulating levels of N-terminal-pro-b-type natriuretic peptide (NT-proBNP). The Interaction between BMI and NT-proBNP with respect to clinical outcomes is not well characterized in patients with acute heart failure.

METHODS AND RESULTS

A total of 686 patients from the biomarker substudy of the ASCEND-HF (Acute Study of Clinical Effectiveness of Nesiritide in Decompensated HF ) clinical trial with documented NT-proBNP levels at baseline were included in the present analysis. Patients were classified by the World Health Organization obesity classification (nonobese: BMI <30 kg/m², Class I obesity: BMI 30-34.9 kg/m², Class II obesity BMI 35-39.9 kg/m², and Class III obesity BMI ≥40 kg/m²). We assessed baseline characteristics and 30- and 180-day outcomes by BMI class and explored the interaction between BMI and NT-proBNP for these outcomes. Study participants had a median age of 67 years (55, 78) and 71% were female. NT-proBNP levels were inversely correlated with BMI (P<0.001). Higher NT-proBNP levels were associated with higher 180-day mortality (adjusted hazard ratio for each doubling of NT-proBNP, 1.40; 95% confidence interval, 1.16, 1.71; P<0.001), but not 30-day outcomes. The effect of NT-proBNP on 180-day death was not modified by BMI class (interaction P=0.24).

CONCLUSIONS

The prognostic value of NT-proBNP was not modified by BMI in this acute heart failure population. NT-proBNP remains a useful prognostic indicator of long-term mortality in acute heart failure even in the obese patient.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00475852.

Plasma NT-proBNP and Cell-Free DNA Concentrations after Prolonged Strenuous Exercise in Working Farm Dogs

BACKGROUND

Plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) concentration is increased in dogs with myocardial dysfunction, and cell-free DNA (cfDNA) increases in numerous disease states. In humans, both of these biomarkers can be altered after endurance exercise.

OBJECTIVE

To investigate the effect of prolonged strenuous exercise on circulating NT-proBNP and cfDNA concentrations in working farm dogs.

ANIMALS

Six healthy, privately owned working farm dogs (4 Huntaways and 2 heading dogs) from the same hill country farm in New Zealand.

METHODS

Prospective, nonrandomised cohort study. Venous blood samples were collected before and after the dogs worked over 4 days. Plasma NT-proBNP concentrations were measured by a commercially available ELISA assay and cfDNA concentrations were determined by fluorometry without prior DNA extraction.

RESULTS

The baseline (before work, Day 1) median plasma NT-proBNP concentration was 664 pmol/L. A linear mixed-effects model showed that work increased plasma NT-proBNP concentrations by 101 ± 9% (P < 0.001), but with each consecutive day of work, NT-proBNP concentrations declined by 16 ± 4% (P < 0.001). The baseline median plasma cfDNA concentration was 653 ng/mL, and plasma cfDNA concentrations increased by 138 ± 45 ng/mL after work (P = 0.004).

CONCLUSIONS AND CLINICAL IMPORTANCE

The plasma concentration of NT-proBNP in healthy Huntaways and heading dogs after work can exceed the upper limit of the reference range. Results in dogs sampled on the day of prolonged strenuous exercise should be interpreted with caution. Plasma concentrations of cfDNA also increase with exercise, but further studies are needed to establish reference ranges in healthy dogs.

Sex-Related Aspects of Biomarkers in Cardiac Disease

Biomarkers play an important role in the clinical management of cardiac care. In particular, cardiac troponins (cTn) and natriuretic peptides are the cornerstones for the diagnosis of acute myocardial infarction (AMI) and for the diagnosis of heart failure (HF), respectively. Current guidelines do not make a distinction between women and men. However, the commonly used "one size fits all" algorithms are topic of debate to improve assessment of prognosis, particularly in women. Due to the high-sensitivity assays (hs-cTn), lower cTn levels (and 99th percentile upper reference limits) were observed in women as compared with men. Sex-specific diagnostic thresholds may improve the diagnosis of AMI in women, though clinical relevance remains controversial and more trials are needed. Also other diagnostic aspects are under investigation, like combined biomarkers approach and rapid measurement strategies. For the natriuretic peptides, previous studies observed higher concentrations in women than in men, especially in premenopausal women who might benefit from the cardioprotective actions. Contrary to hs-cTn, natriuretic peptides are particularly incorporated in the ruling-out algorithms for the diagnosis of HF and not ruling-in. Clinical relevance of sex differences here seems marginal, as clinical research has shown that negative predictive values for ruling-out HF were hardly effected when applying a universal diagnostic threshold that is independent from sex or other risk factors. Apart from the diagnostic issues of AMI in women, we believe that in the future most sex-specific benefits of cardiac biomarkers can be obtained in patient follow-up (guiding therapy) and prognostic applications, fitting modern ideas on preventive and personalized medicine.

The association of N-terminal pro-brain-type natriuretic peptide with hemodynamics and functional capacity in therapy-naive precapillary pulmonary hypertension: results from a cohort study

Background

N-terminal pro-brain-type natriuretic peptide (NT-proBNP) is currently used as a surrogate marker for disease severity in pulmonary hypertension (PH). However, NT-proBNP tends to have a high variability and may insufficiently correlate with hemodynamics and exercise capacity.

Methods

To investigate the association of NT-proBNP with hemodynamics and cardio-pulmonary exercise testing (CPET) in 84 therapy-naive patients with precapillary PH.

Results

NT-proBNP levels were significantly correlated with hemodynamics and CPET parameters except for cardiac index, diffusion capacity, PaO₂ at peak exercise, and peak minute ventilation. NT-proBNP correlated best with hemodynamics and CPET in women and patients >65 years. NT-proBNP correlated better with CPET in pulmonary arterial hypertension compared to chronic thromboembolic PH (CTEPH).

Conclusion

NT-proBNP is associated with disease severity in precapillary PH. The association might be age- and gender-dependent. NT-proBNP may insufficiently correlate with disease severity in CTEPH, possibly due to comorbidity.

Cardiac involvement in myotonic dystrophy: The role of troponins and N-terminal pro B-type natriuretic peptide

BACKGROUND AND AIMS

Myotonic dystrophy type 1 (DM1) and type 2 (DM2) are dominant inherited muscular dystrophies with multiple systemic involvement, often producing cardiac injury. This study sought to determine the clinical significance of elevated high sensitivity cardiac troponin T and I (hs-cTnT and hs-cTnI), and N-terminal pro B-type natriuretic peptide (NT-pro-BNP) in this population.

METHODS

Sixty DM patients (35 men and 25 women; mean age: 45.1 years, range: 12-73 years) underwent clinical cardiac investigations and measurements of serum hs-cTnT, hs-cTnI, creatine kinase (CK), and NT-proBNP. Left ventricular (LV) ejection fraction (EF) was assessed by echocardiography.

RESULTS

Genetic analysis revealed that 46 of the 60 patients were DM1, and 14 DM2. Blood measurements showed persistent elevation of hs-cTnT and CK in 55/60 DM patients (91.73%). In contrast, hs-cTnI values were persistently normal throughout the study. Only 2 patients showed an EF <50%, being the overall range of this population between 40% and 79%. We found ECG abnormalities in 19 patients. Of these patients, 13 showed first or second-degree atrio ventricular (AV) blocks (PR interval ≥ 200 ms), 4 showed a left bundle branch block (LBBB) prolonged (QRS duration ≥120 ms), and 2 had an incomplete bundle branch block (QRS duration between 110 and 119 ms). After excluding patients with EF <50%, NT-pro-BNP measurement > 125 pg/mL was an independent predictor of ECG abnormalities.

CONCLUSIONS

NT-pro-BNP levels may be considered to be used clinically to identify DM patients at increased risk of developing myocardial conduction abnormalities.

Identification and Validation of a Salivary Protein Panel to Detect Heart Failure Early

BACKGROUND

Over 26 million people suffer from heart failure (HF) globally. Current diagnosis of HF relies on clinical evaluation, blood assays and imaging techniques. Our aim is to develop a diagnostic assay to detect HF in at risk individuals within the community using human saliva as a medium, potentially leading to a simple, safe early warning system.

METHODS

Saliva samples were collected from healthy controls (n=36) and HF patients (n=75). Salivary proteome profiles were analysed by Sequential Window Acquisition of All Theoretical fragment ion spectra - Mass Spectrometry (SWATH-MS). A total of 738 proteins were quantified and 177 proteins demonstrated significant differences between HF patients and healthy controls. Candidate biomarkers were chosen based on their abundance and difference between the two cohorts. A multi-protein panel was developed using logistic regression analysis. The diagnostic performance of the multi-protein panel was assessed using receiver operative characteristic curves. The candidate proteins were further confirmed, using western blot analysis, and validated technically, using an independent biological cohort.

RESULTS

A group of six proteins were chosen in the discovery phase as potential candidates based on their differences in the abundance between the two cohorts. During the validation phase, two of the proteins were not detected with western blotting and as such were removed. The final panel consists of four proteins with sensitivity of 83.3%, specificity of 62.5% with an area under ROC curve of 0.78 in discriminating healthy controls from NYHA class I/II HF patients, and was validated in a second independent cohort study.

CONCLUSION

Analysis of salivary proteome using SWATH-MS revealed novel HF-specific protein candidates yielding high diagnostic performance. A multi-centre longitudinal clinical trial will be the next step before clinical implementation of this panel.

Activation of the Nkx2.5-Calr-p53 signaling pathway by hyperglycemia induces cardiac remodeling and dysfunction in adult zebrafish

Hyperglycemia is an independent risk factor for diabetic cardiomyopathy in humans; however, the underlying mechanisms have not been thoroughly elucidated. Zebrafish (Danio rerio) was used in this study as a novel vertebrate model to explore the signaling pathways of human adult cardiomyopathy. Hyperglycemia was induced by alternately immersing adult zebrafish in a glucose solution or water. The hyperglycemic fish gradually exhibited some hallmarks of cardiomyopathy such as myocardial hypertrophy and apoptosis, myofibril loss, fetal gene reactivation, and severe arrhythmia. Echocardiography of the glucose-treated fish demonstrated diastolic dysfunction at an early stage and systolic dysfunction at a later stage, consistent with what is observed in diabetic patients. Enlarged hearts with decreased myocardial density, accompanied by decompensated cardiac function, indicated that apoptosis was critical in the pathological process. Significant upregulation of the expression of Nkx2.5 and its downstream targets calreticulin (Calr) and p53 was noted in the glucose-treated fish. High-glucose stimulation in vitro evoked marked apoptosis of primary cardiomyocytes, which was rescued by the p53 inhibitor pifithrin-μ. In vitro experiments were performed using compound treatment and genetically via cell infection. Genetically, knockout of Nkx2.5 induced decreased expression of Nkx2.5, Calr and p53 Upregulation of Calr resulted in increased p53 expression, whereas the level of Nkx2.5 remained unchanged. An adult zebrafish model of hyperglycemia-induced cardiomyopathy was successfully established. Hyperglycemia-induced myocardial apoptosis was mediated, at least in part, by activation of the Nkx2.5-Calr-p53 pathway in vivo, resulting in cardiac dysfunction and hyperglycemia-induced cardiomyopathy.

A Multiparametric Approach Based on NT-proBNP, ST2, and Galectin3 for Stratifying One Year Prognosis of Chronic Heart Failure Outpatients

Galectin-3 and ST2 are emerging biomarkers involved in myocardial fibrosis. We evaluate the relevance of a multiparametric biomarker approach based on increased serum levels of NT-proBNP, galectin-3, and ST2 in stratifying the prognosis of chronic heart failure (CHF) outpatients. In 315 CHF outpatients in stable clinical condition clinical and echocardiographic evaluations were performed. Routine chemistry and serum levels of NT-proBNP, galectin-3, and ST2 were also assessed. During a 12 month follow-up, cardiovascular death, and/or heart failure (HF) occurred in 64 patients. The presence of NT-proBNP, galectin-3, and ST2 were higher than the recommended cutoffs and were all associated with events at univariate Cox regression analysis, as well as in a multivariate analysis including the three biomarkers. When a score based on the number of biomarkers above the recommended cut-offs was used (in a range of 0-3), it was associated with events both with respect to the univariate (HR 2.96, 95% CI 2.21-3.95, p < 0.001, C-index 0.78) and the multivariate (HR 1.52, 95% CI 1.06-2.17, p: 0.023, C-index 0.87) analyses, after correction for the variables of a reference model. Our results suggest that an easy prognostic approach based on the combination of three biomarkers, although with partially-overlapping pathophysiological mechanisms, is able to identify patients with the highest risk of heart failure progression.

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

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

Targeting N-Terminal Pro-Brain Natriuretic Peptide in Older Versus Younger Acute Decompensated Heart Failure Patients

OBJECTIVES

The aim of this study was to analyze the prognostic value and attainability of N-terminal pro-brain natriuretic peptide (NT-proBNP) levels in young and elderly acute decompensated heart failure (ADHF) patients.

BACKGROUND

Less-effective NT-proBNP-guided therapy in chronic heart failure (HF) has been reported in elderly patients. Whether this can be attributed to differences in prognostic value of NT-proBNP or to differences in attaining a prognostic value is unclear. The authors studied this question in ADHF patients.

METHODS

Our study population comprised 7 ADHF cohorts. We defined absolute (<1,500 ng/l, <3,000 ng/l, <5,000 ng/l, and <15,000 ng/l) and relative NT-proBNP discharge cut-off levels (>30%, >50%, and >70%). Six-month all-cause mortality after discharge was studied for each level in Cox regression analyses, and compared between elderly (age >75 years) and young patients (age ≤75 years). Thereafter, we compared percentages of elderly and young patients attaining NT-proBNP levels (= attainability).

RESULTS

A total of 1,235 patients (59% male, 45% >75 years of age) was studied. Admission levels of NT-proBNP were significantly higher in elderly versus younger patients. The prognostic value of absolute and relative NT-proBNP levels was similar in elderly and young patients. Attainability was significantly lower in elderly patients for all absolute levels and a >50% relative reduction, but not for >30% and >70%. For absolute levels, attainability differences between age groups were decreased to a large extent after correction for admission NT-proBNP and anemia at discharge. For relative levels, attainability differences disappeared after correction for HF etiology and anemia at discharge.

CONCLUSIONS

In young and elderly ADHF patients, it is not the prognostic value of absolute and relative NT-proBNP levels that is different, but the attainability of these levels that is lower in the elderly. This can largely be attributed to factors other than age.

Cardiopulmonary laboratory biomarkers in the evaluation of acute dyspnea

Dyspnea is a common chief complaint in the emergency department, with over 4 million visits annually in the US. Establishing the correct diagnosis can be challenging, because the subjective sensation of dyspnea can result from a wide array of underlying pathology, including pulmonary, cardiac, neurologic, psychiatric, toxic, and metabolic disorders. Further, the presence of dyspnea is linked with increased mortality in a variety of conditions, and misdiagnosis of the cause of dyspnea leads to poor patient-level outcomes. In combination with the history and physical, efficient, and focused use of laboratory studies, the various cardiopulmonary biomarkers can be useful in establishing the correct diagnosis and guiding treatment decisions in a timely manner. Use and interpretation of such tests must be guided by the clinical context, as well as an understanding of the current evidence supporting their use. This review discusses current standards and research regarding the use of established and emerging cardiopulmonary laboratory markers in the evaluation of acute dyspnea, focusing on recent evidence assessing the diagnostic and prognostic utility of various tests. These markers include brain natriuretic peptide (BNP) and N-terminal prohormone (NT-proBNP), mid-regional peptides proatrial NP and proadrenomedullin, cardiac troponins, D-dimer, soluble ST2, and galectin 3, and included is a discussion on the use of arterial and venous blood gases.

Correlation of N-terminal pro-B-type natriuretic peptide levels and cardiac magnetic resonance imaging T2* in patients with β-thalassaemia major

BACKGROUND

Cardiac death secondary to myocardial iron toxicity occurs in 50% of patients with transfusion-dependent β-thalassaemia major. N-terminal pro-B-type natriuretic peptide (NT-proBNP) seems to be a useful tool for early detection of cardiac haemosiderosis. We designed this study to determine whether plasma NT-proBNP levels are predictive of cardiac iron concentration, based on heart T2* assessment by magnetic resonance imaging (MRI).

MATERIALS AND METHODS

We evaluated plasma NT-proBNP levels in 50 patients with β-thalassaemia major, aged 18 to 46 years, with preserved left ventricular systolic function, all of whom had undergone cardiac MRI within 3 months before the study. Next, three groups were defined based on heart T2* value as: group A, patients without evidence of cardiac iron overload (T2*>20 ms); group B, patients with mild to moderate cardiac iron overload (10 ms<T2*<20 ms); group C, patients with severe cardiac iron overload (T2*<10 ms).

RESULTS

NT-proBNP level was not similar among the three groups (p=0.03), being significantly higher in patients in group C (1,104.2±350.5 pg/mL) than in patients in group B (565.9±116.9 pg/mL, p=0.03) or group A (563.5±162.5 pg/mL, p=0.04). The analyses indicate that NT-proBNP levels did not correlate with cardiac iron concentrations (r=0.152, p=0.148).

DISCUSSION

Based on our study, measurements of NT-proBNP levels are not sufficient for early detection of cardiac iron overload. However, NT-proBNP measurements might be used as a tool to guide iron chelation therapy in patients with severe cardiac iron overload. The determination of their clinical use still requires multicentre studies.

The role of cardiac biochemical markers in aortic stenosis

Calcified aortic stenosis is one of the most common causes of heart failure in the elderly. Current guidelines recommend aortic valve replacement in patients with severe disease and evidence of decompensation based on either symptoms or impaired systolic ejection fraction. However, symptoms are often subjective whilst impaired ejection fraction is not a sensitive marker of ventricular decompensation. Interest has surrounded the use of cardiac biochemical markers as objective measures of left ventricular decompensation in aortic stenosis. We will first examine mechanisms of release of biochemical markers associated with myocardial wall stress (BNP/NT-proBNP), myocardial fibrosis (markers of collagen metabolism, galectin-3, soluble ST2) and myocyte death/myocardial ischemia (high-sensitivity cardiac troponins, heart-type fatty acid binding protein, myosin-binding protein C); and discuss future directions of these markers.

Carfilzomib and the cardiorenal system in myeloma: an endothelial effect?

Carfilzomib (Cfz) has been associated with an ~5% incidence of unexplained and unpredictable cardiovascular toxicity in clinical trials. We therefore implemented a detailed, prospective, clinical cardiac and renal evaluation of 62 Cfz-treated myeloma patients, including serial blood pressure (BP), creatinine, troponin, NT-proBNP and pre- and post-treatment echocardiograms, including ejection fraction (EF), average global longitudinal strain and compliance. Pre-treatment elevations in NT-proBNP and BP, as well as abnormal cardiac strain were common. A rise in NT-proBNP occurred frequently post-treatment often without corresponding cardiopulmonary symptoms. A rise in creatinine was common, lessened with hydration and often reversible. All patients had a normal EF pre-treatment. Five patients experienced a significant cardiac event (four decline in EF and one myocardial infarction), of which 2 (3.2%) were considered probably attributable to Cfz. None were rechallenged with Cfz. The ideal strategy for identifying patients at risk for cardiac events, and parameters by which to monitor for early toxicity have not been established; however, it appears baseline echocardiographic testing is not consistently predictive of toxicity. The toxicities observed suggest an endothelial mechanism and further clinical trials are needed to determine whether or not this represents a class effect or is Cfz specific.

Sonographic chest B-lines anticipate elevated B-type natriuretic peptide level, irrespective of ejection fraction

BACKGROUND

Echocardiography and the N-terminal pro-brain-type natriuretic peptide (NT-proBNP) level are important tests for assessing left ventricular function in patients presenting to the emergency department with acute dyspnea. Chest ultrasound is becoming an important tool in diagnosing acute pulmonary edema.

AIM

To assess the diagnostic accuracy of chest ultrasound examination using echocardiography and a curvilinear probe for detecting B-lines in patients presenting with acute pulmonary edema compared with assessment using NT-proBNP.

METHODS

This paper reports a prospective observational study of 61 consecutive patients presenting with symptoms and signs of pulmonary edema and B-profile detected by echocardiography with a 5 MHz curvilinear probe. The emergency department physicians ordered NT-proBNP levels, and critical care physicians trained in ultrasound examination performed echocardiography and chest ultrasounds. The findings of the chest ultrasound were reviewed by another senior physician.

RESULTS

Sixty-one participants were enrolled over a period of 6 months (49.2 % male, with a mean age 66.8). Forty-seven of the 61 patients had a B-profile. The median NT-proBNP level in the patients with B-profile was 6200, compared with the mean level in the patients with an A-profile of 180 (CI 0.33-0.82). The distributions in the two groups differed significantly (p = 0.034). Based on a threshold level of NT-proBNP in relation to age, the sensitivity and specificity (including the 95 % confidence interval) were determined; the sensitivity of finding B-profile on ultrasound was 92.0 %, and the specificity was 91.0 %. The positive predictive value of the B-profile was 97.0 %, and the negative predictive value was 71.0 %. The systolic function in the subjects with a B-profile was below 50 in 84.3 % of the subjects and normal in 15.7 % of the subjects. An A-profile was present in all of the subjects with systolic function >55 %. In the subjects with a B-profile, 94 % had a Framingham score of CHF >4; the subjects with all A-profile had scores <4, p < 0.0001. There was an NHANES score of >3 in 96 % of the subjects with a B-profile, and all of the subjects with an A-profile had scores <3 (p < 0.0001).

CONCLUSIONS

Detecting the B-profile with an echocardiography probe (curvilinear 5 MHz) in lung ultrasound is highly sensitive and specific for elevated NT-proBNP helping in diagnosing pulmonary edema, although of resolution inferior to micro convex probes.

Impact of using different guideline recommended serum natriuretic peptide thresholds on the diagnosis and referral rates of a diagnostic heart failure clinic

AIMS

The aims of this study were to determine the diagnostic yield of a dedicated heart failure diagnosis clinic and the impact of using different guideline recommended N-terminal pro B-type natriuretic peptide (NT-proBNP) referral thresholds on diagnosis and referral patterns.

METHODS AND RESULTS

Patients referred by primary care between September 2011 and May 2013 were included in the analysis. Data collected included baseline characteristics, NT-proBNP levels, echocardiographic and clinical findings, final diagnosis and outcome. The impact of using Newcastle (locally modified age-adjusted NT-proBNP thresholds), National Institute for Health and Care Excellence (NICE) and European Society of Cardiology (ESC) NT-proBNP thresholds on diagnosis and referrals was determined by applying the different guidelines to this population. A total of 208 patients were referred; median age 77.5 years and 62.5% were women. Thirty-four patients (16.3%) had systolic heart failure, 50 patients (24.0%) had heart failure with preserved ejection fraction. One hundred and six patients (51.0%) did not have heart failure. Using NICE guidelines (NT-proBNP ≥ 400 ng/l) instead of the Newcastle age-adjusted NT-proBNP referral thresholds results in 59 fewer referrals, but eight heart failure diagnoses were missed. Using the ESC cut-off of NT-proBNP ≥ 125 ng/l would result in 88 additional referrals; one diagnosis of heart failure would be missed. Over a mean follow-up of 16.8 ± 6 months there were 21 deaths and 47 hospital admissions.

CONCLUSION

The Newcastle age-adjusted thresholds led to more referrals in comparison to NICE guidelines but are more sensitive in diagnosing heart failure. Using ESC recommended thresholds results in a similar diagnostic yield to our age-adjusted thresholds, but has the potential to significantly increase the referrals in patients ≥ 75 years, which may result in a lower diagnostic yield.

Cardiovascular biomarkers and sex: the case for women

Measurement of biomarkers is a critical component of cardiovascular care. Women and men differ in their cardiac physiology and manifestations of cardiovascular disease. Although most cardiovascular biomarkers are used by clinicians without taking sex into account, sex-specific differences in biomarkers clearly exist. Baseline concentrations of many biomarkers (including cardiac troponin, natriuretic peptides, galectin-3, and soluble ST2) differ in men versus women, but these sex-specific differences do not generally translate into a need for differential sex-based cut-off points. Furthermore, most biomarkers are similarly diagnostic and prognostic, regardless of sex. Two potential exceptions are cardiac troponins measured by high-sensitivity assay, and proneurotensin. Troponin levels are lower in women than in men and, with the use of high-sensitivity assays, sex-specific cut-off points might improve the diagnosis of myocardial infarction. Proneurotensin is a novel biomarker that was found to be predictive of incident cardiovascular disease in women, but not men, and was also predictive of incident breast cancer. If confirmed, proneurotensin might be a unique biomarker of disease risk in women. With any biomarker, an understanding of sex-specific differences might improve its use and might also lead to an enhanced understanding of the physiological differences between the hearts of men and women.

Evidence of an Association between Age-Related Functional Modifications and Pathophysiological Changes in Zebrafish Heart

BACKGROUND

Zebrafish have become a valuable model for the study of developmental biology and human disease, such as cardiovascular disease. It is difficult to discriminate between disease-related and age-related alterations.

OBJECTIVE

This study was aimed to investigate the effects and potential mechanisms of age-related cardiac modifications in an older zebrafish population.

METHODS

In this study, we calculated the survival rate and measured the spinal curvature through the aging process. A swimming challenge test was performed and showed that swimming capacity and endurance dramatically dropped in older fish groups.

RESULTS

To find out the effect of stress on zebrafish during the aging process, we recorded electrocardiograms on zebrafish and showed that during stress, aging not only led to a significant reduction in heart rate, but also caused other age-related impairments, such as arrhythmias and ST-T depression. Echocardiography showed a marked increase in end-diastolic ventricular dimensions and in isovolumic relaxation time and a notably slower mean and peak velocity of the bulboventricular valve in older zebrafish, but stroke volume and cardiac output were not different in young and old zebrafish. Both nppa and nppb (cardiac fetal genes for natriuretic factor) expression detected by real-time polymerase chain reaction analysis increased in older fish compared to the younger group. Histological staining revealed fibrosis within cardiomyocytes and an increase in ventricular myocardial density and a decrease in epicardial vessel dimensions in older fish hearts that may correlate with a deterioration of cardiac function and exercise capacity.

CONCLUSION

These data suggest that cardiac functional modifications in zebrafish are comparable to those in humans and may partly be due to changes in the cardiovascular system including cardiac fetal gene reprogramming, myocardial density, and epicardial vessel dimensions.

Clinical and echocardiographic characteristics of elderly hospitalized patients with high levels of NT-proBNP without clinical diagnosis of heart failure

BACKGROUND

Patients with high NT-proBNP levels but without heart failure (HF) diagnosis have a higher risk of cardiovascular events and mortality; however, there are few data about their characteristic, especially in the elderly.

AIMS

To compare the clinical and echocardiographic characteristics of elderly hospitalized patients with and without increased NT-proBNP and with and without a diagnosis of HF.

METHODS

We reviewed 209 charts of patients admitted to an acute care ward (mean age 78.9 years, SD 10.2, 62% women). We classified the patients into four groups: no HF with or without increased (>900 pg/mL) NT-proBNP (HF-/BNP-, N = 89 and HF-/BNP+, N = 41), and HF with or without increased NT-proBNP (HF+/BNP-, N = 4 and HF+/BNP+, N = 75). The groups were compared with respect to demographic and clinical characteristics, symptoms at admission, comorbidities, echocardiographic parameters, and cardiovascular events at 180 days.

RESULTS

Patients in the groups HF+/BNP+ and HF-/BNP+ were older, with higher serum creatinine, blood urea nitrogen, and lower serum hemoglobin compared to patients in the HF-/BNP- group. The prevalence of ischemic heart disease, pulmonary hypertension, and atrial fibrillation progressively decreased across the HF+/BNP+, HF-/BNP+, and HF-/BNP- groups. The prevalence of abnormal echocardiographic findings in the HF-/BNP+ group was intermediate compared to the other two groups for severe aortic or mitralic regurgitation, monophasic transmitralic pattern, biatrial atriomegaly, ejection fraction, akinesia extension, and PAPs. The same pattern was observed for cardiovascular events at follow-up.

DISCUSSION

Elderly patients without a diagnosis of HF, but with high NT-proBNP serum concentration have intermediate clinical characteristics compared to the other two groups.

CONCLUSION

NT-proBNP may be a useful marker of silent cardiac damage.

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.

Utility of NT-proBNP as a rule-out test for left ventricular dysfunction in very old people with limiting dyspnoea: the Newcastle 85+ Study

BACKGROUND

Guidelines advocate using B-type natriuretic peptides in the diagnostic work-up of suspected heart failure (HF). Their main role is to limit echocardiography rates by ruling out HF/LV dysfunction where peptide level is low. Recommended rule-out cut points vary between guidelines. The utility of B-type natriuretic peptides in the very old (85+) requires further investigation, with optimal cut points yet to be established. We examined NT-proBNP's utility, alone and in combination with history of myocardial infarction (MI), as a rule-out test for LV dysfunction in very old people with limiting dyspnoea.

METHODS

DESIGN

Cross-sectional analysis.

SETTING

Population-based sample; North-East England.

PARTICIPANTS

155 people (aged 87-89) with limiting dyspnoea.

MEASURES

Dyspnoea assessed by questionnaire. Domiciliary echocardiography performed; LV systolic/diastolic function graded. NT-proBNP measured (Roche Diagnostics). Receiver operating characteristic analyses examined NT-proBNP's diagnostic accuracy for LV dysfunction.

RESULTS

AUC for LVEF less than or equal to 50% was poor (0.58, 95% CI 0.49-0.65), but good for LVEF less than or equal to 40% (0.80, 95% CI 0.73-0.86). At ESC cut point (125 ng/l), few cases of systolic dysfunction were missed (NPV 94-100%, depending on severity), but echocardiography (88%) and false positive rates (56-81 per 100 screened) were high. At NICE cut point (400 ng/l), echocardiography (51%) and false positive rates (33-45) were lower; exclusionary performance was good for LVEF less than or equal to 40% (1 case missed per 100 screened, 15% of cases; NPV 97%), but poor for LVEF less than or equal to 50% (16 cases missed per 100 screened, 45% of cases; NPV 68%). Incorporating isolated moderate/severe diastolic dysfunction into target condition increased the proportion of cases missed (lower NPV), whilst improving case detection. Incorporating MI history as an additional referral prompt slightly reduced the number of cases missed at expense of higher echocardiography and false positive rates.

CONCLUSIONS

High echocardiography rates and poor exclusionary performance for mild degrees of systolic dysfunction and for diastolic dysfunction limit NT-proBNP's utility as a rule-out test for LV dysfunction in very old people with limiting dyspnoea. Incorporating MI history as an additional echocardiography prompt yields no overall benefit compared to using NT-proBNP level alone.

Impact of body mass index on plasma N-terminal ProB-type natriuretic peptides in Chinese atrial fibrillation patients without heart failure

BACKGROUND

An inverse relationship between body mass index (BMI) and circulating levels of N-terminal proB-type natriuretic peptide (NT-proBNP) has been demonstrated in subjects with and without heart failure. Obesity also has been linked with increased incidence of atrial fibrillation (AF), but its influence on NT-proBNP concentrations in AF patients remains unclear. This study aimed to investigate the effect of BMI on NT-proBNP levels in AF patients without heart failure.

METHODS

A total of 239 consecutive patients with AF undergoing catheter ablation were evaluated. Levels of NT-proBNP and clinical characteristics were compared in overweight or obese (BMI≥25 kg/m2) and normal weight (BMI<25 kg/m2) patients.

RESULTS

Of 239 patients, 129 (54%) were overweight or obese. Overweight or obese patients were younger, more likely to have a history of nonparoxysmal AF, hypertension, and diabetes mellitus. Levels of NT-proBNP were significantly lower in overweight or obese than in normal weight subjects (P<0.05). The relationship of obesity and decreased NT-proBNP levels persisted in subgroup of hypertension, both gender and both age levels (≥65 yrs and <65 yrs).Multivariate linear regression identified BMI as an independent negative correlate of LogNT-proBNP level.

CONCLUSIONS

An inverse relationship between BMI and plasma NT-proBNP concentrations have been demonstrated in AF patients without heart failure. Overweight or obese patients with AF appear to have lower NT-proBNP levels than normal weight patients.

Do laboratories follow heart failure recommendations and guidelines and did we improve? The CARdiac MArker Guideline Uptake in Europe (CARMAGUE)

BACKGROUND

Natriuretic peptides (NP) are well-established markers of heart failure (HF). During the past 5 years, analytical and clinical recommendations for measurement of these biomarkers have been published in guidelines. The aim of this follow-up survey was to investigate how well these guidelines for measurement of NP have been implemented in laboratory practice in Europe.

METHODS

Member societies of the European Federation of Clinical Chemistry and Laboratory Medicine were invited in 2009 to participate in a web-based audit questionnaire. The questionnaire requested information on type of tests performed, decision limits for HF, turn-around time and frequency of testing.

RESULTS

There was a moderate increase (12%) of laboratories measuring NP compared to the initial survey in 2006. The most frequently used HF decision limits for B-type NP (BNP) and N-terminal BNP (NT-proBNP) were, respectively, 100 ng/L and 125 ng/L, derived from the package inserts in 55%. Fifty laboratories used a second decision limit. Age or gender dependent decision limits were applied in 10% (8.5% in 2006). The vast majority of laboratories (80%) did not have any criteria regarding frequency of testing, compared to 33% in 2006.

CONCLUSIONS

The implementation of NP measurement for HF management was a slow process between 2006 and 2009 at a time when guidelines had just been established. The decision limits were derived from package insert information and literature. There was great uncertainty concerning frequency of testing which may reflect the debate about the biological variability which was not published for most of the assays in 2009.

Cystatin C: a potential biomarker for pulmonary arterial hypertension

BACKGROUND AND OBJECTIVE

Cystatin C (CysC), a novel marker of renal function, predicts left heart failure and cardiovascular mortality. The hypothesis that serum CysC levels correlate with right ventricular (RV) morphology, function and pressure in pulmonary arterial hypertension (PAH) was tested.

METHODS

As part of a prospective study, 14 PAH subjects and 10 matched controls underwent same-day echocardiography, cardiac magnetic resonance imaging (CMR), and phlebotomy for CysC, brain natriuretic peptide (BNP), and N-terminal BNP (NT-ProBNP). RV ejection fraction (RVEF), end-diastolic volume, end-systolic volume and mass were calculated using CMR. RV systolic pressure (RVSP), strain and diastolic function (including tricuspid valve (TV) E velocity, A velocity, e' velocity, E/A ratio and E/e' ratio) were assessed using echocardiography.

RESULTS

RVSP was significantly elevated in PAH subjects versus controls (57 ± 17 vs. 28 ± 8 mm Hg, P < 0.0001). CysC was abnormally elevated in the PAH cohort when compared with controls (1.00 ± 0.23 vs 0.78 ± 0.05 mg/L, P = 0.001). CysC positively correlated with RVSP (rho 0.61, P = 0.002), RV end-diastolic volume (rho 0.50, P = 0.01), RV end-systolic volume (rho 0.58, P = 0.003), mass index (rho 0.66, P = 0.0004), strain (rho 0.51, P = 0.01) and strain rate (rho 0.51, P = 0.01) and negatively correlated with RVEF (rho -0.58, P = 0.003) and TV e' (rho -0.75, P < 0.0001). The same correlations with BNP and NT-ProBNP were comparable with CysC.

CONCLUSIONS

In a small cohort, CysC accurately correlates with RV pressure, function and morphology. CysC may represent a novel PAH biomarker.