Plasma brain natriuretic peptide concentration: impact of age and gender

Poor acute outcome in congestive heart failure is associated with increases in the plasma static oxidation-reduction potentials (sORP) in men but not in women

OBJECTIVES

In congestive heart failure (CHF), men are younger, more likely to have reduced ejection fraction (HF-rEF), and to be diabetic compared to women. Despite this, sex differences in oxidative stress have yet to be explored in CHF.

METHODS

Data from 67 males and 63 females hospitalized for CHF were collected. Static oxidation-reduction potential (sORP), a relative indicator of oxidative stress, and capacity ORP (icORP), a relative indicator of antioxidant capacity, were measured from plasma samples. We examined whether sex modified the relationship between ORP and hospital discharge disposition (poor outcome: death, hospice), along with other demographics, medications, and diagnostic parameters.

RESULTS

Males with poor outcomes had higher sORP and icORP values than females (P < 0.05). For those with a good outcome, there were no differences between the sexes (P > 0.05). Males were younger and more likely to have HF-rEF and diabetes. Controlling for these variables did not account for the sex differences in ORP measures. Regardless of sex, higher creatinine was related to higher sORP and icORP, while lower magnesium and potassium were related to higher sORP and icORP, respectively.

DISCUSSION

Increases in sORP during CHF are partially affected by sex and acute outcomes, but are also related to variables without sexual biases.

Hemodynamic Determinants of the Biologic Variation of N-Terminal Pro-B-Type Natriuretic Peptide in Patients With Stable Systolic Chronic Heart Failure

BACKGROUND CONTEXT

Biologic variation of N-terminal pro-B-type natriuretic peptide (NT-proBNP) in chronic heart failure (CHF) may affect blood levels and risk stratification. The sources of NT-proBNP variation are unknown.

METHODS AND RESULTS

We performed NT-proBNP measurements and clinical and hemodynamic assessments in 50 patients with heart failure with reduced ejection fraction (HFrEF) who met criteria for clinical stability over 2 time intervals. Hemodynamic variables were measured with the use of inert gas rebreathing and impedance cardiography. Heart rhythm was monitored with the use of external electrocardiographic event recorders throughout the study. Determinants of NT-proBNP-levels and both absolute (ΔNT-proBNP_abs) and relative (ΔNT-proBNP_%) changes at 1-week and 2-week intervals were identified with the use of univariable and multivariable linear mixed-effects models and linear regression analyses, respectively. Clinical and hemodynamic variables did not significantly change between study visits. The individual variation of NT-proBNP at 2 weeks was 9.2% (range 3.9%-18.6%). Weight and glomerular filtration rate were independently associated with baseline NT-proBNP concentrations (P = .01 and P = .005, respectively). There was no relationship between absolute and relative changes of NT-proBNP at 1-week intervals and changes in clinical and hemodynamic variables. Absolute change of NT-proBNP at 2-week intervals was associated with absolute change in left cardiac work index (P = .008), and relative change in NT-proBNP at 2-week intervals was determined by relative change of thoracic fluid content index (P = .008) and diastolic blood pressure (P = .01). The coefficients of determination (R²) for the multivariable models with Δ_1wkNT-proBNP_abs, Δ_2-weeksNT-proBNP_abs, Δ_1wkNT-proBNP_%, and Δ_2wksNT-proBNP_% as dependent variables were 0.21, 0.19, 0.10, and 0.32, respectively.

CONCLUSIONS

In patients with stable HFrEF, changes in clinical and hemodynamic variables only marginally contribute to the variation of NT-proBNP.

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.

Elevation of B-Type Natriuretic Peptide at Discharge is Associated With 2-Year Mortality After Transcatheter Aortic Valve Replacement in Patients With Severe Aortic Stenosis: Insights From a Multicenter Prospective OCEAN-TAVI (Optimized Transcatheter Valvular Intervention-Transcatheter Aortic Valve Implantation) Registry

Background

In this study, we sought to investigate the 2‐year prognostic impact of B‐type natriuretic peptide (BNP) levels at discharge, following transcatheter aortic valve replacement.

Methods and Results

We enrolled 1094 consecutive patients who underwent transcatheter aortic valve replacement between 2013 and 2016. Study patients were stratified into 2 groups according to survival classification and regression tree analysis (high versus low BNP groups). We evaluated the impact of high BNP on 2‐year mortality compared with that of low BNP using a multivariable Cox model, and assessed whether this stratification would improve predictive accuracy for determining 2‐year mortality by assessing time‐dependent net reclassification improvement and integrated discrimination improvement. The median age of patients was 85 years (quartile 82–88), and 29.2% of the study population were men. The median Society of Thoracic Surgeons score was 6.8 (4.7–9.5), and BNP at discharge was 186 (93–378) pg/mL. All‐cause mortality following discharge was 7.9% (95% CI, 5.8–9.9%) at 1 year and 15.4% (95% CI, 11.6–19.0%) at 2 years. The survival classification and regression tree analysis revealed that the discriminating BNP level to discern 2‐year mortality was 202 pg/mL, and that elevated BNP had a statistically significant impact on outcomes, with an adjusted hazard ratio of 2.28 (1.36–3.82, P=0.002). The time‐dependent net reclassification improvement (P=0.047) and integrated discrimination improvement (P=0.029) analysis revealed that the incorporation of BNP stratification with other clinical variables significantly improved predictive accuracy for 2‐year mortality.

Conclusions

Elevation of BNP at discharge is associated with 2‐year mortality after transcatheter aortic valve replacement.

N-Terminal Pro B-Type Natriuretic Peptide and High-Sensitivity Cardiac Troponin T Levels Are Related to the Extent of Hibernating Myocardium in Patients With Ischemic Heart Failure

BACKGROUND

Increased N-terminal pro b-type natriuretic peptide (NT-proBNP) and high-sensitivity cardiac troponin T (hs-cTnT) can identify patients with heart failure (HF) who are at increased risk of cardiac events. The relationship of these biomarkers to the extent of hibernating myocardium and scar has not been previously characterized in patients with ischemic left ventricular dysfunction and HF.

METHODS

Patients with ischemic HF meeting recruitment criteria and undergoing perfusion and fluorodeoxyglucose-positron emission tomography to define myocardial hibernation and scar were included in the study. A total of 39 patients (mean age 67 ± 8 years) with New York Heart Association class II-IV HF and ischemic cardiomyopathy (ejection fraction [EF], 27.9% ± 8.5%) were enrolled in the study.

RESULTS

Serum NT-proBNP and hs-cTnT levels were elevated in patients with ≥ 10% hibernating myocardium compared with those with < 10% (NT-pro-BNP, 7419.10 ± 7169.5 pg/mL vs 2894.6 ± 2967.4 pg/mL; hs-cTnT, 789.3 ± 1835.3 pg/mL vs 44.8 ± 78.9 pg/mL; P < 0.05). The overall receiver operating characteristic under the curve value for NT-proBNP and hs-cTnT to predict hibernating myocardium was 0.76 and 0.78, respectively (P < 0.05). The NT-proBNP (P = 0.02) and hs-cTnT (P < 0.0001) levels also correlated with hibernation, particularly in patients with ≥ 10% scar, independent of EF, age, and estimated glomerular filtration rate. No differences were noted in biomarker levels for patients with vs those without ≥ 10% scar.

CONCLUSIONS

NT-proBNP and hs-cTnT levels are elevated in patients with ischemic HF hibernation and are correlated with the degree of hibernation but not with the presence or extent of scar. Taken together, these data support the novel concept that NT-proBNP and hs-cTnT release in patients with ischemic HF reflects the presence and extent of hibernating myocardium.

Anemia considerations when assessing natriuretic peptide levels in ED patients

INTRODUCTION

The incidence of heart failure (HF) has reached epidemic levels in western populations, and the majority of these patients are admitted to hospitals through the emergency department (ED). We aimed to aid clinicians assessing natriuretic peptide (NP) levels in cases with suspected HF. In this study, we investigated the effect of anemia on amino-terminal pro-BNP (NT-proBNP) and on B-type natriuretic peptide (BNP) levels.

METHODS

This retrospective study examined patients who were admitted to the ED with suspected HF. After admission, the treating physician requested complete blood count and creatinine tests with NT-proBNP (n=2.637) or BNP (n=11.159). The exclusion criteria were used to minimize the factors that could affect the NT-proBNP and BNP results. We examined the data using the Mann-Whitney U test, Chi-square test, Spearman correlation test, and multivariate linear regression analyses.

RESULTS

The NT-proBNP and BNP levels were statistically higher in the groups with anemia (p=0.016 and p=0.009, respectively). There was a statistically significant negative correlation between hemoglobin and NP levels (r=-0.272, p<0.001 for NT-proBNP and r=-0.179, p<0.001 for BNP). The results indicated that advanced age and low hemoglobin levels were significantly associated with the increase in NT-proBNP (p=0.024 and p=0.004, respectively). Advanced age, low hemoglobin and low GFR-MDRD levels were significantly associated with the increase in BNP (p<0.001, p=0.002 and p=0.013, respectively).

DISCUSSION

The data suggest that clinicians examining patients admitted to the ED with suspected HF should consider that anemia could lead to increases in NT-proBNP and BNP levels.

Plasma brain natriuretic peptide levels are elevated in patients with cancer

BACKGROUND

Natriuretic peptides have been proposed as biomarkers of cardiovascular disease, especially heart failure. Brain natriuretic peptide (BNP) has also been shown to be upregulated at the transcriptional and translational levels by pro-inflammatory cytokines in cardiac myocytes. Although we often measure plasma BNP levels in cancer patients, it remains unknown whether cancer-related inflammation affects the plasma BNP levels. We investigated the relationship between the BNP and human cancers.

METHODS

We retrospectively studied 2,923 patients in whom the plasma BNP levels and serum C-reactive protein (CRP) were measured and echocardiography was performed. Patients with clinically evident heart failure (NYHA II or higher), heart disease requiring medical treatment or surgery, renal dysfunction, and inflammatory disease were excluded. There were 234 patients in the final analysis. Blood sampling was performed before surgery and chemotherapy. In addition, we evaluated the relationship between the inflammation and plasma BNP levels in mouse models of colon cancer.

RESULTS

Of the 234 patients, 80 were diagnosed with cancer. Both the plasma BNP and serum CRP levels were significantly higher in cancer patients than those without. There were no significant differences in the echocardiographic parameters. There was a significant positive correlation between the plasma BNP and serum CRP levels in cancer patients (r = 0.360, P<0.01) but not in those without. In cancer patients, only the CRP correlated with the BNP independent of the age, creatinine level, hypertension, and body mass index. In addition, in nude mice with subcutaneous colon cancer, the plasma BNP level was elevated compared with that in non-cancer mice, and there was a significant relationship between the plasma BNP and serum levels of the inflammatory markers.

CONCLUSIONS

In cancer patients, as well as colon cancer model mice, the plasma BNP levels were elevated, possibly due to cancer-related inflammation. The effect of cancer on the BNP levels should be considered when using BNP as an indicator of heart failure in cancer patients.

Epidemiology of heart failure with preserved ejection fraction

Heart failure (HF) with preserved ejection fraction (HFpEF) is a clinical syndrome associated with poor quality of life, substantial health-care resource utilization, and premature mortality. We summarize the current knowledge regarding the epidemiology of HFpEF with a focus on community-based studies relevant to quantifying the population burden of HFpEF. Current data regarding the prevalence and incidence of HFpEF in the community as well as associated conditions and risk factors, risk of morbidity and mortality after diagnosis, and quality of life are presented. In the community, approximately 50% of patients with HF have HFpEF. Although the age-specific incidence of HF is decreasing, this trend is less dramatic for HFpEF than for HF with reduced ejection fraction (HFrEF). The risk of HFpEF increases sharply with age, but hypertension, obesity, and coronary artery disease are additional risk factors. After adjusting for age and other risk factors, the risk of HFpEF is fairly similar in men and women, whereas the risk of HFrEF is much lower in women. Multimorbidity is common in both types of HF, but slightly more severe in HFpEF. A majority of deaths in patients with HFpEF are cardiovascular, but the proportion of noncardiovascular deaths is higher in HFpEF than HFrEF.

Role of Biomarkers for the Prevention, Assessment, and Management of Heart Failure: A Scientific Statement From the American Heart Association

BACKGROUND AND PURPOSE

Natriuretic peptides have led the way as a diagnostic and prognostic tool for the diagnosis and management of heart failure (HF). More recent evidence suggests that natriuretic peptides along with the next generation of biomarkers may provide added value to medical management, which could potentially lower risk of mortality and readmissions. The purpose of this scientific statement is to summarize the existing literature and to provide guidance for the utility of currently available biomarkers.

METHODS

The writing group used systematic literature reviews, published translational and clinical studies, clinical practice guidelines, and expert opinion/statements to summarize existing evidence and to identify areas of inadequacy requiring future research. The panel reviewed the most relevant adult medical literature excluding routine laboratory tests using MEDLINE, EMBASE, and Web of Science through December 2016. The document is organized and classified according to the American Heart Association to provide specific suggestions, considerations, or contemporary clinical practice recommendations.

RESULTS

A number of biomarkers associated with HF are well recognized, and measuring their concentrations in circulation can be a convenient and noninvasive approach to provide important information about disease severity and helps in the detection, diagnosis, prognosis, and management of HF. These include natriuretic peptides, soluble suppressor of tumorgenicity 2, highly sensitive troponin, galectin-3, midregional proadrenomedullin, cystatin-C, interleukin-6, procalcitonin, and others. There is a need to further evaluate existing and novel markers for guiding therapy and to summarize their data in a standardized format to improve communication among researchers and practitioners.

CONCLUSIONS

HF is a complex syndrome involving diverse pathways and pathological processes that can manifest in circulation as biomarkers. A number of such biomarkers are now clinically available, and monitoring their concentrations in blood not only can provide the clinician information about the diagnosis and severity of HF but also can improve prognostication and treatment strategies.

Natriuretic peptides in the evaluation and management of degenerative mitral regurgitation: a systematic review

Progression of degenerative mitral regurgitation (MR) leads to irreversible cardiac damage. Therefore, longitudinal follow up to determine the optimal timing of surgery is critical. Current data indicates that in addition to the standard of care-assessing for symptoms and signs of left ventricular (LV) decompensation with routine echocardiography-serial measurement of natriuretic peptides offers a quantitative means to identify patients who may benefit from closer supervision, if not surgery. Natriuretic peptide levels, and specifically changes from baseline, identify both symptomatic patients and others likely to develop cardiac dysfunction. Moreover, because natriuretic peptides are complimentary to the echocardiographic assessment of MR. Finally, changes in natriuretic peptides levels are predictive of pre- and post-operative outcomes. In short, natriuretic peptides add objectivity to the management of degenerative MR, which may aid practitioners in identifying patients who could benefit from intensive monitoring, stress testing, and perhaps mitral surgery.

Differentiating heart failure phenotypes using sex-specific transcriptomic and proteomic biomarker panels

Aims

Heart failure with preserved ejection fraction (HFpEF) accounts for 30–50% of patients with heart failure (HF). A major obstacle in HF management is the difficulty in differentiating between HFpEF and heart failure with reduced ejection fraction (HFrEF) using conventional clinical and laboratory investigations. The aim of this study is to develop robust transcriptomic and proteomic biomarker signatures that can differentiate HFpEF from HFrEF.

Methods and results

A total of 210 HF patients were recruited in participating institutions from the Alberta HEART study. An expert clinical adjudicating panel differentiated between patients with HFpEF and HFrEF. The discovery cohort consisted of 61 patients, and the replication cohort consisted of 70 patients. Transcriptomic and proteomic data were analysed to find panels of differentiating HFpEF from HFrEF. In the discovery cohort, a 22‐transcript panel was found to differentiate HFpEF from HFrEF in male patients with a cross‐validation AUC of 0.74, as compared with 0.70 for N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP) in those same patients. An ensemble of the transcript panel and NT‐pro‐BNP yielded a cross‐validation AUC of 0.80. This performance improvement was also observed in the replication cohort. An ensemble of the transcriptomic panel with NT‐proBNP produced a replication AUC of 0.90, as compared with 0.74 for NT‐proBNP alone and 0.73 for the transcriptomic panel.

Conclusions

We have identified a male‐specific transcriptomic biomarker panel that can differentiate between HFpEF and HFrEF. These biosignatures could be further replicated on other patients and potentially be developed into a blood test for better management of HF patients.

Role of circulating factors in cardiac aging

Worldwide increase in life expectancy is a major contributor to the epidemic of chronic degenerative diseases. Aging, indeed, simultaneously affects multiple organ systems, and it has been hypothesized that systemic alterations in regulators of tissue physiology may regulate this process. Cardiac aging itself is a major risk factor for cardiovascular diseases and, because of the intimate relationship with the brain, may contribute to increase the risk of neurodegenerative disorders. Blood-borne factors may play a major role in this complex and still elusive process. A number of studies, mainly based on the revival of parabiosis, a surgical technique very popular during the 70s of the 20th century to study the effect of a shared circulation in two animals, have indeed shown the potential that humoral factors can control the aging process in different tissues. In this article we review the role of circulating factors in cardiovascular aging. A better understanding of these mechanisms may provide new insights in the aging process and provide novel therapeutic opportunities for chronic age-related disorders.

Low NT-proBNP levels: An early sign for the diagnosis of ischemic heart failure

BACKGROUND

N-terminal pro-brain natriuretic peptide (NT-proBNP) is seen to be mostly elevated in patients with acute heart failure (AHF). However, cases of AHF presenting with low NT-proBNP levels have been reported. In this study designed to investigate the factors associated with low NT-proBNP levels in AHF patients, we discovered that etiology and related factors have an influence on NT-proBNP levels.

METHODS

In this study, 154 AHF patients met the study criteria (117 men, median age 74years; left ventricular ejection fraction [LVEF] 46±13%; New York Heart Association [NYHA] classes II-IV). We analyzed the different clinical variables of patients based on plasma NT-proBNP levels. In addition, we identified the differences in NT-proBNP levels between ischemic and non-ischemic etiologies, as well as the relationships between time from symptom onset to ED visit and NT-proBNP levels.

RESULTS

The group with low NT-proBNP levels showed an ischemic association, higher LVEF, lower NYHA class and shorter time from symptom onset to ED visit. Plasma NT-proBNP levels were lower in the ischemic group than in the non-ischemic group (P<0.01). Meanwhile, NT-proBNP levels were relatively low in patients during early phases of AHF hospitalization and increased with time from symptom onset to ED visit (P<0.01).

CONCLUSION

We inferred that low NT-proBNP levels may infer the ischemic etiology especially in patients with normal LVEF in the early phases of AHF hospitalization.

Impact of HIV infection and antiretroviral treatment on N-terminal prohormone of brain natriuretic peptide as surrogate of myocardial function

OBJECTIVE

Vasoactive cardiovascular hormones such as the N-terminal prohormone of brain natriuretic peptide (NT-proBNP) are produced upon ventricular stretch and play a central role in neurohumoral pathways of the heart regulating cardiovascular remodeling and volume homeostasis. The impact of HIV infection on these neurohumoral pathways of the heart and its potential reversibility by combinations of antiretroviral therapies remain unclear.

METHODS

We assessed serum levels of NT-proBNP in 219 antiretroviral therapy-naïve HIV-infected patients with a normal cardiac and renal status at treatment initiation and after attainment of viremic control.

RESULTS

Before antiretroviral therapy, NT-proBNP as a surrogate of myocardial function displayed a significant correlation with absolute CD4 cell count (r = -0.31; P < 0.001) as well as with HIV viral load (r = 0.26; P < 0.001). The median levels of NT-proBNP were 80 pg/ml (36-205) in patients with a CD4 cell count less than 200 cells/μl and 42 pg/ml (20-80; P < 0.001) with a CD4 cell count more than 500 cells/μl. After viremic control, no statistical correlation was present.

CONCLUSION

Higher NT-proBNP levels were observed in treatment-naïve patients with low CD4 cell count and high HIV viral load, indicating a subclinical impact of HIV infection on myocardial function. This association is reversible by the initiation of antiretroviral therapy and subsequent viral suppression.

Natriuretic Peptide System Activation in Acute Heart Failure Patients with Diabetes

BACKGROUND

Elevated B-type natriuretic peptide (BNP) is a hallmark in heart failure (HF). Diabetic patients with chronic HF seem to have higher BNP than nondiabetics. We studied, in acute HF, if BNP levels are different between diabetics and nondiabetics.

METHODS

From a prospectively recruited population of acute HF patients, we selected a convenience sample. In pair-matched analysis, each diabetic patient was matched with a nondiabetic of the same age (±1 year), gender, and according to left ventricular systolic dysfunction. Diabetics and nondiabetics were compared. Cox-regression analysis was used to analyse the prognostic impact of diabetes.

RESULTS

We studied 328 patients, mean age: 78 years, 44.5% male. Diabetics were more often hypertensive and had ischemic HF; they had higher body mass index, lower haemoglobin, and worse renal function. Diabetics were more often discharged on ACE inhibitors/ARB, antiplatelet therapy, and statins. Neither admission nor discharge BNP values differed between diabetics and pair-matched nondiabetics. One-year mortality was also nondifferent between pairs of diabetics and nondiabetics: 44 (26.8%) and 46 (28.0%), respectively. HR for 1-year mortality in diabetics was 1.00 (95% CI: 0.82-1.24) compared with nondiabetics.

CONCLUSIONS

HF patients with diabetes have similar neurohumoral activation when compared with nondiabetics. One-year mortality is also nondifferent after matching for age, gender, and systolic function.

Factors influencing brain natriuretic peptide levels in healthy pregnant women

BACKGROUND

The normal range of plasma brain natriuretic peptide (BNP) in pregnant women is still unclear. Moreover, pregnant women experience dynamic body weight changes and suffer from anemia, but effects on maternal BNP have not been investigated. This study aimed to reveal the normal plasma BNP range and examine the effects of physiological changes on BNP among pregnant women.

METHODS AND RESULTS

Plasma BNP, hemoglobin, plasma creatinine and BMI were measured in 58 non-pregnant control women and in 773 normal pregnant women at late pregnancy, early postpartum and 1-month postpartum. Mean plasma BNP (in pg/mL) was 11.8 (95% confidence interval: 0-27.5) in non-pregnant women, 17.9 (0-44.7, p<0.001) at late pregnancy, 42.5 (0-112.6, p<0.001) early postpartum and 16.1 (0-43.9, p=0.001) 1-month postpartum. Multiple regression analysis revealed that pre-delivery BNP levels were negatively correlated with BMI (p<0.001) and hemoglobin (p=0.002) and positively correlated with creatinine (p<0.001). Post-delivery BNP was positively associated with body weight change during pregnancy (p=0.001) and post-delivery creatinine (p=0.010) but negatively associated with body weight loss at delivery (p<0.001) and post-delivery hemoglobin (p=0.004).

CONCLUSION

Even normal pregnancy affects plasma BNP, particularly in the early postpartum period, indicative of cardiac stress. Plasma BNP levels are affected by BMI, body weight changes, creatinine and hemoglobin levels; therefore, these factors should be considered when analysing cardiac function and the physiological implications of BNP levels in pregnant women.

Plasma levels of atrial and brain natriuretic peptides in apparently healthy subjects: Effects of sex, age, and hemoglobin concentration

BACKGROUND

To examine whether the use of one value of natriuretic peptides to define "normal" is appropriate in all individuals, and to assess the influence of sex, age, and other variables on atrial and brain natriuretic peptides (ANP, BNP) levels.

METHODS AND RESULTS

A total of 1375 apparently healthy people (women:155, men:1220), aged 18-70years were enrolled. Both ANP and BNP levels were higher in women than in men (ANP: 12.50±6.82pg/mL vs 8.18±4.19pg/mL; BNP: 9.85±7.63pg/mL vs 7.03±6.97pg/mL). The subjects were divided into three age groups: group I, 18-30years; group II, 30-50years; group III, 50-70years. First, the influence of age on ANP and BNP levels was examined. In women, both ANP and BNP levels were higher in groups II and III than those in group I. In men, ANP and BNP levels increased with age. Second, sex differences in ANP and BNP levels due to age were examined. ANP level was higher in women than that in men in all age groups. BNP level was higher in women than that in men in groups I and II. Multivariate analysis indicated that both ANP and BNP levels were influenced by age, hemoglobin level, and platelet counts.

CONCLUSION

Because ANP and BNP levels in healthy subjects are influenced by sex, age, and hemoglobin levels, the use of a single value to define "normal" in all individuals is not appropriate.

Accessory pathway location affects brain natriuretic peptide level in patients with Wolff-Parkinson-White syndrome

PURPOSE

The purpose of this study was to investigate the relationship between the accessory pathway location and brain natriuretic peptide (BNP) level in patients with Wolff-Parkinson-White (WPW) syndrome.

METHODS

We divided 102 WPW syndrome patients with normal left ventricular systolic function into four groups: those with manifest right (MR, n = 14), manifest septal (MS, n = 11), manifest left (ML, n = 30), and concealed (C, n = 47) accessory pathways. BNP level and electrophysiological properties, including difference in timing of the ventricular electrogram between the His bundle area and the distal coronary sinus area (His-CS delay), which indicate intraventricular dyssynchrony, were compared.

RESULTS

BNP levels (pg/dl) were higher in the MR and MS groups than in the ML and C groups (MR, 64 ± 58; MS, 55 ± 45; ML, 17 ± 15; C, 25 ± 21; P < 0.001). AV intervals (ms) were shorter in the MR and MS groups than in the ML and C groups (MR, 76 ± 16; MS, 83 ± 6; ML, 101 ± 19; C, 136 ± 20; P < 0.001). His-CS delay (ms) was longer in the MR group than in the other groups (MR, 50 ± 15; MS, 21 ± 7; ML, 23 ± 10; C, 19 ± 8; P < 0.001). The AV interval (P < 0.01) and the His-CS delay (P < 0.001) were negatively and positively correlated, respectively, with the BNP level.

CONCLUSION

Anterograde conduction with a right or septal accessory pathway increased the BNP level in WPW syndrome patients with normal cardiac function.

NT-proBNP in Children With Left to Right Shunt and Dilated Cardiomyopathy

Background

B-type natriuretic peptide (BNP) levels are elevated in children with congenital heart disease involving a left-to-right shunt (LRS) and are also raised in dilated cardiomyopathy (DCM). As far as we know, there are few reports in the literature comparing the change of the NT-proBNP in LRS and DCM especially in the pediatric age group.

Objectives

The aim of the study was to compare the changes of the NT-proBNP in pediatric patients with LRS and DCM. Correlation between the levels of NT-proBNP and the echocardiographic parameters in both groups was determined.

Patients and Methods

A total of 30 children (13 males and 17 females) participated in the study. There were 11/30 (36.7%) DCM and 19/30 (63.3%) LRS. The control group consisted of 44 healthy infants and children. Manifestations of heart failure (decompensation) were recorded. The NT-pro BNP levels were measured. The following Echo parameters were assessed: systolic function (ejection fraction and fraction shortening), pulmonary to systemic flow (Qp/Qs) in LRS, pulmonary flow and pulmonary artery pressure (SPAP) and LV diastolic function (E-wave, A-wave, E/A ratio and deceleration time).

Results

Clinically 17/30 (56.7%) (11 of the LRS and 5 of the DCM) were decompensated. Significant shunt was present in 15/19 (78.9%) in LRS. Systolic dysfunction was presented in 5/30 (16.7%) cases (4 patients were DCM and one case was LRS). Two types of diastolic dysfunction, impaired relaxation in 5/22 (22.7%) patients and restrictive-like filling pattern in 5/16 (31.2 %) were observed. The NT-Pro BNP level was significantly elevated 11 and 16 times in the LRS and DCM groups respectively. Negative significant correlations were observed between the levels of NT-ProBNP and the following echo variables; EDD, LAD, E wave and E/A ratio in the LRS patients. Positive significant correlations were observed between the levels of NT-ProBNP and the following echo variables; PAP and QP/QS in the LRS. Both the PAP and QP/QS were higher in the elevated NT-Pro BNP group compared to the normal level group. The NT-Pro BNP level was elevated in all 17/30 (56.7%) decompensated patients (11 were LRS, 6 were DCM) (P = 0.002). However, the level was elevated in only 7/13 (23.3%) of the compensated patients (3 were LRS, 4 were DCM) (P = 0.002). The NT-Pro BNP level was also elevated in 18/19 cases with pulmonary hypertension (P = 0.01). Finally, we conclude that the NT-ProBNP level is elevated in both LRS and DCM in pediatric age. This elevation is more remarkable with heart failure and increased PAP in both diseased groups. The level was also elevated and correlated to Qp/Qs in the LRS patients.

Conclusions

So, we recommend the use of NT-ProBNP as a routine marker for following up patients with heart failure and pulmonary hypertension in LRS and DCM.

Synergistic Utility of Brain Natriuretic Peptide and Left Ventricular Global Longitudinal Strain in Asymptomatic Patients With Significant Primary Mitral Regurgitation and Preserved Systolic Function Undergoing Mitral Valve Surgery

Background—

In asymptomatic patients with ≥3+ mitral regurgitation and preserved left ventricular (LV) ejection fraction who underwent mitral valve surgery, we sought to discover whether baseline LV global longitudinal strain (LV-GLS) and brain natriuretic peptide provided incremental prognostic utility.

Methods and Results—

Four hundred and forty-eight asymptomatic patients (61±12 years and 69% men) with ≥3+ primary mitral regurgitation and preserved left ventricular ejection fraction, who underwent mitral valve surgery (92% repair) at our center between 2005 and 2008, were studied. Baseline clinical and echocardiographic data (including LV-GLS using Velocity Vector Imaging, Siemens, PA) were recorded. The Society of Thoracic Surgeons score was calculated. The primary outcome was death. Mean Society of Thoracic Surgeons score, left ventricular ejection fraction, mitral effective regurgitant orifice, indexed LV end-diastolic volume, and right ventricular systolic pressure were 4±1%, 62±3%, 0.55±0.2 cm 2 , 58±13 cc/m 2 , and 37±15 mm Hg, respectively. Forty-five percent of patients had flail. Median log-transformed BNP and LV-GLS were 4.04 (absolute brain natriuretic peptide: 60 pg/dL) and −20.7%. At 7.7±2 years, death occurred in 41 patients (9%; 0% at 30 days). On Cox analysis, a higher Society of Thoracic Surgeons score (hazard ratio 1.55), higher baseline right ventricular systolic pressure (hazard ratio 1.11), more abnormal LV-GLS (hazard ratio 1.17), and higher median log-transformed BNP (hazard ratio 2.26) were associated with worse longer-term survival (all P <0.01). Addition of LV-GLS and median log-transformed BNP to a clinical model (Society of Thoracic Surgeons score and baseline right ventricular systolic pressure) provided incremental prognostic utility (χ 2 for longer-term mortality increased from 31–47 to 61; P <0.001).

Conclusions—

In asymptomatic patients with significant primary mitral regurgitation and preserved left ventricular ejection fraction who underwent mitral valve surgery, brain natriuretic peptide and LV-GLS provided synergistic risk stratification, independent of established factors.

Brain Natriuretic Peptide and the Severity of Aortic Regurgitation: Is There Any Correlation?

We aimed to evaluate the correlation between aortic regurgitation severity and brain natriuretic (BNP) levels as a marker for left ventricular dysfunction. Sixty consecutive male patients (mean age 22 ± 3 years) with isolated chronic aortic regurgitation were enrolled in the study together with a control group of 30 age-matched healthy volunteers (group A). Patients were classified with regard to aortic regurgitation vena contracta width as follows: group B, < 3 mm, mild ( n = 16); group C, ≥ 3 and < 6 mm, moderate ( n = 26); group D, ≥ 6 mm, severe ( n = 18). BNP measurements were performed with a fluorescence immunoassay kit. BNP levels were increased in patients with aortic regurgitation, and severity of regurgitation had a significant influence on BNP levels. This effect can be explained by the volume loading effect of aortic regurgitation.

Multimarker assessment for the prediction of renal function improvement after percutaneous revascularization for renal artery stenosis

BACKGROUND

Identifying patients likely to have improved renal function after percutaneous transluminal renal angioplasty and stenting (PTRA) for renal artery stenosis (RAS) is challenging. The purpose of this study was to use a comprehensive multimarker assessment to identify those patients who would benefit most from correction of RAS.

METHODS

In 127 patients with RAS and decreased renal function and/or hypertension referred for PTRA, quantification of hemodynamic cardiac stress using B-type natriuretic peptide (BNP), renal function using estimated glomerular filtration rate (eGFR), parenchymal renal damage using resistance index (RI), and systemic inflammation using C-reactive protein (CRP) were performed before intervention.

RESULTS

Predefined renal function improvement (increase in eGFR ≥10%) at 6 months occurred in 37% of patients. Prognostic accuracy as quantified by the area under the receiver-operating characteristics curve for the ability of BNP, eGFR, RI and CRP to predict renal function improvement were 0.59 (95% CI, 0.48-0.70), 0.71 (95% CI, 0.61-0.81), 0.52 (95% CI, 0.41-0.65), and 0.56 (95% CI, 0.44-0.68), respectively. None of the possible combinations increased the accuracy provided by eGFR (lower eGFR indicated a higher likelihood for eGFR improvement after PTRA, P=ns for all). In the subgroup of 56 patients with pre-interventional eGFR <60 mL/min/1.73 m(2), similar findings were obtained.

CONCLUSIONS

Quantification of renal function, but not any other pathophysiologic signal, provides at least moderate accuracy in the identification of patients with RAS in whom PTRA will improve renal function.

Biomarkers for Heart Failure: An Update for Practitioners of Internal Medicine

Biomarkers have become an integral part of practicing medicine, especially in heart failure. The natriuretic peptides are commonly used in the evaluation of heart failure, but their role extends beyond diagnosis and includes risk stratification and management of heart failure patients. Newer biomarkers have arrived and are becoming part of routine care of heart failure patients. Both ST2 and high-sensitivity troponin have significant prognostic value for mortality, but also may assist in the titration of medical therapy. Procalcitonin can help guide appropriate antibiotic use in patients with heart failure. The ability to appropriately use and interpret these biomarkers is imperative to the care of heart failure patients, especially as these newer biomarkers become widely used.

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.

How peptide technology has improved costs and outcomes in patients with heart failure

INTRODUCTION

Heart failure (HF) is characterized by substantial health and economic burden, mainly attributed to increased hospitalizations and readmissions. Its diagnosis remains challenging due to the non-specific nature of the initial symptoms of the disease. Recently, scientific evidence has highlighted the potential of natriuretic peptides (NP) in improving the diagnosis and prognosis of HF and, by extension, in restraining healthcare costs. The present review aimed at providing evidence of their optimal use in terms of economic and health outcomes.

AREAS COVERED

Systematic literature research limited to studies published from February 2006 to February 2016 was performed with the aim of identifying and analyzing all cost-effectiveness and other economic evaluation studies that investigated the economic and health outcomes of NPs use as screening and management tools for HF. Expert commentary: NP testing either added in the standard of care, or substituting frequently used diagnostic procedures for the diagnosis and management of HF, regardless of the healthcare setting of interest, was proved to be a valid tool for clinical decision-making. Moreover it was associated with improved patient outcomes and important cost-savings mainly attributed to lower admission and readmission rates, shorter hospitalization length and improved health-related quality of life.

The Natural History of Patients With Isolated Metabolic Syndrome

OBJECTIVES

To define the natural history of patients with isolated metabolic syndrome (MS).

PATIENTS AND METHODS

Metabolic syndrome is associated with increased risk of cardiovascular mortality. Patients with isolated MS are a subset of patients with MS who do not meet the diagnostic criteria of hypertension (HTN) and diabetes mellitus (DM). Data were collected prospectively on a population-based random sample of 1042 Olmsted County, Minnesota, residents aged 45 years or older who underwent clinical evaluation, medical record abstraction, and echocardiography (visit 1: January 1,1997, to December 31, 2000). The cohort was subdivided into healthy controls, those with isolated MS, and those with MS with HTN and/or DM groups. After 4 years, patients returned for visit 2 (September 1, 2001, to December 30, 2004). After visit 2, we have a median of 8.3 years of follow-up.

RESULTS

There was a higher incidence of HTN, DM, and obesity in the isolated MS group at visit 2 (P<.001) than in healthy controls. Patients with isolated MS did not have significantly higher rates of cardiovascular mortality (hazard ratio [HR], 0.85; 95% CI, 0.23-3.13; P=.80) or development of heart failure (HR, 1.29; 95% CI, 0.58-2.73; P=.53) compared with healthy controls over 8 years of follow-up after visit 2. However, patients with MS with HTN and/or DM had higher rates of cardiovascular mortality (HR, 2.40; 95% CI, 1.00-5.83; P=.02) and heart failure (HR, 2.24; 95% CI, 1.16-4.32; P=.02) compared with healthy controls over 8 years of follow-up after visit 2.

CONCLUSION

Isolated MS was associated with increased risk for the development of HTN, DM, and obesity, but not increased mortality or heart failure over an 8-year period compared with healthy controls. Future studies should determine whether aggressive management of risk factors in isolated MS will prevent progression to MS.

Associations of serum n-3 and n-6 polyunsaturated fatty acids with plasma natriuretic peptides

BACKGROUND/OBJECTIVES

The n-3 and n-6 polyunsaturated fatty acids (PUFAs) have been associated with lower risk of cardiovascular disease (CVD), but little is known about their association with natriuretic peptides (NPs), a marker for CVD risk. The aim of this study was to investigate the association of serum n-3 and n-6 PUFAs with NPs.

SUBJECTS/METHODS

A cross-sectional analysis of the association between serum n-3 and n-6 PUFAs with plasma N-terminal atrial (NT-proANP) and brain (NT-proBNP) NPs in a population-based sample of 985 men aged 46-65 years from Eastern Finland.

RESULTS

After adjustment for age and examination year, only serum n-6 PUFA arachidonic acid (ARA) was inversely associated with NT-proANP (P-trend across quartiles=0.02), but further adjustments for conventional risk factors (body mass index, smoking, alcohol intake, systolic blood pressure, low-density lipoprotein cholesterol and history of CVD) attenuated the association (P-trend=0.10). The associations with the other PUFAs were not statistically significant. Among the PUFAs, only serum n-3 PUFA docosapentaenoic acid (DPA; P-trend=0.03) and ARA (P-trend=0.02) had inverse associations with NT-proBNP after adjustment for age and examination years. The associations were again attenuated after further adjustments but remained statistically significant for DPA (P-trend=0.05). Our results also suggested that the inverse associations may be more evident among those using beta-blockers.

CONCLUSIONS

Our study suggests little overall impact of serum n-3 or n-6 PUFAs on plasma NPs.

Sex differences in clinical characteristics and long-term outcome in acute decompensated heart failure patients with preserved and reduced ejection fraction

In patients with acute decompensated heart failure (ADHF), sex differences considering clinical and pathophysiologic features are not fully understood. We investigated sex differences in left ventricular (LV) ejection fraction (LVEF), plasma B-type natriuretic peptide (BNP) levels, and prognostic factors in patients with ADHF in Japan. We studied 748 consecutive ADHF patients of 821 patients registered in the ADHF registry between January 2007 and December 2014. Patients were divided into four groups based on sex and LVEF [reduced (ejection fraction, or EF, <50%, heart failure with reduced EF, or HFrEF) or preserved (EF ≥50%, heart failure with preserved LVEF, or HFpEF)]. The primary endpoint was the combination of cardiovascular death and heart failure (HF) admission. The present study consisted of 311 female patients (50% HFrEF, 50% HFpEF) and 437 male patients (63% HFrEF, 37% HFpEF). There was significant difference between sexes in the LVEF distribution profile. The ratio of HFpEF patients was significantly higher in female patients than in male patients ( P = 0.0004). Although there were no significant sex differences in median plasma BNP levels, the prognostic value of BNP levels was different between sexes. Kaplan-Meier analysis revealed that the high BNP group had worse prognosis than the low BNP group in male but not in female patients. In multivariate analysis, log transformed BNP at discharge predicted cardiovascular events in male but not in female HF patients (female, hazard ratio: 1.169; 95% confidence interval: 0.981–1.399; P = 0.0806; male, hazard ratio: 1.289; 95% confidence interval: 1.120–1.481; P = 0.0004). In patients with ADHF, the distribution of LV function and the prognostic significance of plasma BNP levels for long-term outcome were different between the sexes.

B-Type Natriuretic Peptide, Aldosterone, and Fluid Management in ARDS

BACKGROUND

Conservative fluid management increases ventilator-free days without influencing overall mortality in acute respiratory distress syndrome. Plasma concentrations of B-type natriuretic peptide (a marker of ventricular filling) or aldosterone (a marker of effective circulating volume) may identify patients for whom fluid management impacts survival.

METHODS

This was a retrospective analysis of the Fluid and Catheter Treatment Trial (FACTT), a randomized trial comparing conservative with liberal fluid management in acute respiratory distress syndrome. Using plasma collected at study enrollment, we measured B-type natriuretic peptide and aldosterone by immunoassay. Multivariable analyses examined the interaction between B-type natriuretic peptide or aldosterone concentration and fluid strategy with regard to 60-day in-hospital mortality.

RESULTS

Among 625 patients with adequate plasma, median B-type natriuretic peptide concentration was 825 pg/mL (interquartile range, 144-1,574 pg/mL), and median aldosterone was 2.49 ng/dL (interquartile range, 1.1-4.3 ng/dL). B-type natriuretic peptide did not predict overall mortality, correlate with fluid balance, or modify the effect of conservative vs liberal fluid management on outcomes. In contrast, among patients with lower aldosterone concentrations, conservative fluid management increased ventilator-free days (17.1 ± 9.8 vs 12.5 ± 10.3, P < .001) and decreased mortality (19% vs 30%, P = .03) (P value for interaction = .01).

CONCLUSIONS

In acute respiratory distress syndrome, B-type natriuretic peptide does not modify the effect of fluid management on outcomes. Lower initial aldosterone appears to identify patients for whom conservative fluid management may improve mortality.

Cardiovascular biomarkers in paired maternal and umbilical cord blood samples at term and near term delivery

BACKGROUND

Cardiovascular biomarkers might help to identify fetuses or pregnancies at risk.

AIM

To examine the umbilical cord neonatal and maternal levels of cardiovascular biomarkers at the time of delivery, and to correlate maternal and fetal biomarker levels to each other, to gestational age and to delivery mode.

STUDY DESIGN

In a prospective, observational, cross-sectional, single-center study biomarkers were measured in paired maternal and umbilical venous cord blood samples.

SUBJECTS

The sample cohort included 66 sets of fetal and maternal blood samples (11 after multiple gestation, 53 after cesarean section, 17 after exposure to labor).

OUTCOME MEASURES

Midregional pro-adrenomedullin (MRproADM), midregional-pro atrial natriuretic peptide (MRproANP), brain natriuretic peptide (BNP), n-terminal-pro brain natriuretic peptide (NTproBNP), copeptin, and high sensitive troponin I (hsTnI) levels were measured.

RESULTS

Mean ± SEM for biomarker levels in umbilical venous/maternal blood were: MRproADM [nmol/L] 1.02 ± 0.04/1.24 ± 0.08, MRproANP [pmol/L] 215.53 ± 12.96/54.65 ± 3.41, BNP [pg/mL] 32.02 ± 3.37/19.76 ± 3.29, NTproBNP [pg/mL] 1228.94 ± 91.73/71.48 ± 8.65, copeptin [pmol/L] 103.42 ± 22.89/10.41 ± 1.71, and hsTnI [pg/mL] 13.54 ± 5.17/4.91 ± 2.37. Fetal MRproANP, NTproBNP, and BNP were inversely correlated with gestational age. Maternal and fetal MRproANP (r=0.472, p=0.002) and copeptin (r=0.572, p<0.001) levels were correlated, whereas there was no feto-maternal correlation for the other biomarkers. Fetal copeptin was elevated after exposure to labor.

CONCLUSIONS

Biomarker levels appear to be regulated independently in mother and fetus. Fetal biomarkers are influenced by gestational age and delivery mode. In this study on term and near term pregnancies without specific fetal pathology, correlation between paired maternal and fetal biomarker levels was weak or not demonstrable.

Biomarkers in heart failure: the importance of inconvenient details

The proliferation of cardiac-related biomarkers and advocacy for their use has often come without adequate discussion of limitations in the interpretation of values and their best use in heart failure (HF) patients to provide a balanced assessment of how cardiac biomarkers are advocated for use in HF and areas where we would argue there are no gaps in knowledge. We include suggestions to address these issues. We have focused on peer-reviewed publications over the period 2000 to present. Most studies have used samples at one or at most two points in time to define risk. Although biomarkers might add to the magnitude of risk, it is unclear how often they lead to changes in treatment. We suggest that defining the use of serial biomarker testing over time would be more helpful. To do this, it is necessary to take into account the biomarker's analytical and biological variability in addition to its ability to define and monitor therapy. These factors are often overlooked leading to conclusions that may be statistically significant but not clinically or analytically robust. An appreciation of the value and limitations of biomarker use is important to all clinicians who manage HF patients. If the proper studies are done so that biomarkers are used optimally, they will likely be helpful in defining when and how to intervene. If we continue as we have, we will continue to have ambiguity about the use of these valuable probes in the assessment and management of HF.

Chronic subcutaneous brain natriuretic peptide therapy in asymptomatic systolic heart failure

AIMS

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

METHODS AND RESULTS

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

CONCLUSION

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