Detection of left ventricular enlargement and impaired systolic function with plasma N-terminal pro brain natriuretic peptide concentrations

Adjuvant Whole Breast Radiotherapy Improve Survival in Women with Heart Failure with Reduced Ejection Fraction Receiving Breast-Conserving Surgery

BACKGROUND

to date, no data on the effect of adjuvant whole breast radiotherapy (WBRT) on oncologic outcomes, such as all-cause death, locoregional recurrence (LRR), and distant metastasis (DM), are available in women with left-side breast invasive ductal carcinoma (IDC) and heart failure with reduced ejection fraction (HFrEF).

PATIENTS AND METHODS

we included 294 women with left-breast IDC at clinical stages IA-IIIC and HFrEF receiving breast-conserving surgery (BCS) followed by adjuvant WBRT or non-adjuvant WBRT. We categorized them into two groups based on their adjuvant WBRT status and compared their overall survival (OS), LRR, and DM outcomes. We calculated the propensity score and applied inverse probability of treatment weighting (IPTW) to create a pseudo-study cohort. Furthermore, we performed a multivariate analysis of the propensity score-weighted population to obtain hazard ratios (HRs).

RESULTS

in the IPTW-adjusted model, adjuvant WBRT (adjusted HR [aHR]: 0.60; 95% confidence interval [CI]: 0.44-0.94) was a significant independent prognostic factor for all-cause death (p = 0.0424), and the aHR (95% CI) of LRR and DM for adjuvant WBRT was 0.33 (0.24-0.71; p = 0.0017) and 0.37 (0.22-0.63; p = 0.0004), respectively, compared with the non-adjuvant WBRT group.

CONCLUSION

Adjuvant WBRT was associated with a decrease in all-cause death, LRR, and DM in women with left IDC and HFrEF compared with non-adjuvant WBRT.

Aptamer-Based Proteomic Platform Identifies Novel Protein Predictors of Incident Heart Failure and Echocardiographic Traits

BACKGROUND

We used a large-scale, high-throughput DNA aptamer-based discovery proteomic platform to identify circulating biomarkers of cardiac remodeling and incident heart failure (HF) in community-dwelling individuals.

METHODS

We evaluated 1895 FHS (Framingham Heart Study) participants (age 55±10 years, 54% women) who underwent proteomic profiling and echocardiography. Plasma levels of 1305 proteins were related to echocardiographic traits and to incident HF using multivariable regression. Statistically significant protein-HF associations were replicated in the HUNT (Nord-Trøndelag Health) study (n=2497, age 63±10 years, 43% women), and results were meta-analyzed. Genetic variants associated with circulating protein levels (pQTLs) were related to echocardiographic traits in the EchoGen (n=30 201) and to incident HF in the CHARGE (n=20 926) consortia.

RESULTS

Seventeen proteins associated with echocardiographic traits in cross-sectional analyses (false discovery rate <0.10), and 8 of these proteins had pQTLs associated with echocardiographic traits in EchoGen (P<0.0007). In Cox models adjusted for clinical risk factors, 29 proteins demonstrated associations with incident HF in FHS (174 HF events, mean follow-up 19 [limits, 0.2-23.7] years). In meta-analyses of FHS and HUNT, 6 of these proteins were associated with incident HF (P<3.8×10-5; 3 with higher risk: NT-proBNP [N-terminal proB-type natriuretic peptide], TSP2 [thrombospondin-2], MBL [mannose-binding lectin]; and 3 with lower risk: ErbB1 [epidermal growth factor receptor], GDF-11/8 [growth differentiation factor-11/8], and RGMC [hemojuvelin]). For 5 of the 6 proteins, pQTLs were associated with echocardiographic traits (P<0.0006) in EchoGen, and for RGMC, a protein quantitative trait loci was associated with incident HF (P=0.001).

CONCLUSIONS

A large-scale proteomics approach identified new predictors of cardiac remodeling and incident HF. Future studies are warranted to elucidate how biological pathways represented by these proteins may mediate cardiac remodeling and HF risk and to assess if these proteins can improve HF risk prediction.

Independent Impact of Gynoid Fat Distribution and Free Testosterone on Circulating Levels of N-Terminal Pro-Brain Natriuretic Peptide (NT-proBNP) in Humans

Background: Natriuretic peptides (NPs), including brain natriuretic peptide (BNP), are neurohormones involved in the regulation of water-sodium balance and the maintenance of cardiovascular homeostasis. A higher concentration of NPs is observed in females, but the mechanism behind this difference has not been fully elucidated. Methods: Randomly chosen 255 volunteers from the general population were examined. Overall, 196 people without severe cardiovascular disease were included (mean age 48 years, 35.7% male). A comprehensive assessment was performed, including anthropometric measurements, N-terminal pro-brain natriuretic peptide (NT-proBNP), total testosterone (TT) and sex hormone-binding globulin (SHBG) concentration, transthoracic echocardiography (ECHO), and body composition analysis by direct dual-energy X-ray absorptiometry (DEXA). The univariate analysis adjusted by the known affecting factors determined which measurements were independently associated with NT-proBNP concentration. Results: NT-proBNP concentration was positively associated with gynoid fat mass, gynoid/total fat (G/TF) mass index, SHBG and negatively with android/gynoid (A/G) fat mass index, TT and calculated free testosterone (CFT) concentrations. Furthermore, body composition parameters remained independently associated with NT-proBNP levels even after adjusting for CFT and SHBG. Conclusion: In the population without severe cardiovascular disease, the NT-proBNP concentration is independently associated with lower availability of testosterone and higher gynoid fat distribution, which may explain higher NPs levels in females.

NT-proBNP, Cardiometabolic Risk Factors, and Nutritional Status in Hemodialysis Patients

Background

We aimed to evaluate the association between NT-proBNP and malnutrition in HD patients while taking into account the four established categories of parameters for diagnosis of protein energy wasting (PEW).

Methods

A cross-sectional study was performed in Afro-Caribbean dialysis patients. One component in each of the 4 categories for the wasting syndrome was retained: serum albumin ≤ 38 g/L, BMI ≤ 23 Kg/m², serum creatinine ≤ 818 µmol/L, and normalized protein catabolic rate (nPCR) ≤ 0.8 g/kg/day. NT-proBNP was assessed using a chemiluminescence immunoassay. Two multivariate logistic regression models were performed to determine the parameters associated with high NT-proBNP concentrations.

Results

In 207 HD patients, 16.9% had PEW (at least three components). LVEF lower than 60% was found in 13.8% of patients. NT-proBNP levels ranged from 125 to 33144 pg/mL. In model 1, high levels of NT-proBNP (≥6243 pg/mL) were independently associated with PEW OR 14.2 (3.25–62.4), male gender 2.80 (1.22–6.57), hsCRP > 5 mg/L 3.90 (1.77–8.57), and dialysis vintage > 3 years 3.84 (1.35–10.8). In model 2, LVEF OR was 0.93 (0.88–0.98). NT-proBNP concentrations were significantly higher when the PEW component number was higher.

Conclusion

In dialysis patients, high NT-proBNP levels must draw attention to cardiac function but also to nutritional status.

Point-of-care devices for physiological measurements in field conditions. A smorgasbord of instruments and validation procedures

Point-of-care (POC) devices provide quick diagnostic results that increase the efficiency of patient care. Many POC devices are currently available to measure metabolites, blood gases, hormones, disease biomarkers or pathogens in samples as diverse as blood, urine, feces or exhaled breath. This diversity is potentially very useful for the comparative physiologist in field studies if proper validation studies are carried out to justify the accuracy of the devices in non-human species under different conditions. Our review presents an account of physiological parameters that can be monitored with POC devices and surveys the literature for suitable quantitative and statistical procedures for comparing POC measurements with reference "gold standard" procedures. We provide a set of quantitative tools and report on different correlation coefficients (Lin's Concordance Correlation Coefficient or the more widespread Pearson correlation coefficient), describe the graphical assessment of variation using Bland-Altman plots and discuss the difference between Model I and Model II regression procedures. We also report on three validation datasets for lactate, glucose and hemoglobin measurements in birds using the newly proposed procedures. We conclude the review with a haphazard account of future developments in the field, emphasizing the interest in lab-on-a-chip devices to carry out more complex experimental measurements than the ones currently available in POC devices.

Psychometric testing of the Duke Activity Status Index in patients with heart failure

BACKGROUND

Patients with heart failure (HF) experience difficulty performing activities of daily living. As impaired functional status is adversely associated with outcomes, it is important to accurately evaluate patient functional status. The Duke Activity Status Index (DASI) is a 12-item, self-administered questionnaire to measure functional status. However, its psychometric properties have not been determined in patients with HF. The purpose of this study was to examine the psychometric properties of the DASI in patients with HF.

METHODS AND RESULTS

We used data from 297 patients with a diagnosis of HF (age 61±11 years, 31% female) for psychometric testing. Internal consistency reliability of the DASI was high (Cronbach's alpha=0.86). Criterion-related validity was supported by significantly different DASI scores for each New York Heart Association classification. Construct validity was supported by significant correlation of DASI scores with health-related quality of life (r = -0.64), depressive symptoms (r = -0.44), and N-terminal B-type natriuretic peptide (r = -0.14).

CONCLUSION

Our data support the psychometric properties of the DASI as a measure of functional status in patients with HF. This instrument can be used to evaluate functional status and enhance health care provider understanding of functional status related to daily living from the patient perspective.

Amino-terminal pro-brain natriuretic peptide: a biomarker for diagnosis, prognosis and management of heart failure

There is a substantial need for a diagnostic tool to aid in the early diagnosis of heart failure and in the recognition of those at risk for its development, as well as in guidance of therapy. Testing for amino-terminal pro-brain natriuretic peptide (NT-proBNP) has been recognized to have utility in the diagnosis, prognosis and management of heart failure. In addition, numerous other applications for NT-proBNP testing are now recognized, such as evaluation of patients with heart disease in the absence of heart failure, as well as the diagnostic and prognostic evaluation of patients with acute coronary syndromes or pulmonary thromboembolism.

N-terminal probrain natriuretic peptide is a stronger predictor of cardiovascular mortality than C-reactive protein and albumin excretion rate in elderly patients with type 2 diabetes: the Casale Monferrato population-based study

OBJECTIVE

To study whether N-terminal probrain natriuretic peptide (NT-proBNP) is a short-term independent predictor of both all-cause and cardiovascular (CV) mortality in type 2 diabetic patients and to establish whether albuminuria and C-reactive protein (CRP) affect this relationship.

RESEARCH DESIGN AND METHODS

The prospective study included 1,825 type 2 diabetic patients from the population-based cohort of the Casale Monferrato study. CV risk factors, preexisting CVD, and NT-proBNP levels were evaluated at baseline. All-cause and CV mortality were assessed 5.5 years after baseline examination. Multivariate Cox proportional hazards modeling was used to estimate mortality hazard ratios (HRs).

RESULTS

During the follow-up period, 390 people died (175 for CVD) out of 9,101 person-years of observations. A significantly increased mortality risk by quartiles of NT-proBNP was observed (test for trend, P < 0.001). NT-proBN P values >91 pg/mL conferred HRs of 2.05 (95% CI 1.47-2.86) for all-cause and 4.47 (2.38-8.39) for CV mortality, independently of CV risk factors, including CRP and albumin excretion rate (AER). The association was also significant for modest rises in NT-proBNP levels and in patients without microalbuminuria and CVD at baseline (upper quartiles HRs 3.82 [95% CI 1.24-13.75]) and 3.14 [1.00-9.94]). Albuminuria and NT-proBNP had an additive effect on mortality, though the association was stronger for NT-proBNP.

CONCLUSIONS

NT-proBNP is a strong independent predictor of short-term CV mortality risk in elderly people with type 2 diabetes, including those without preexisting CVD. This association is evident even in people with slightly increased values, is not modified by CRP, and is additive to that provided by AER.

NH2-terminal probrain natriuretic peptide is associated with diabetes complications in the EURODIAB Prospective Complications Study: the role of tumor necrosis factor-α

OBJECTIVE

Circulating levels of NH(2)-terminal probrain natriuretic peptide (NT-proBNP), a marker of acute heart failure, are associated with increased risk of cardiovascular disease (CVD) in the general population. However, there is little information on the potential role of NT-proBNP as a biomarker of vascular complications in type 1 diabetic patients. We investigated whether serum NT-proBNP levels were associated with micro- and macrovascular disease in type 1 diabetic subjects.

RESEARCH DESIGN AND METHODS

A cross-sectional nested case-control study from the EURODIAB Prospective Complications Study of 507 type 1 diabetic patients was performed. Case subjects (n = 345) were defined as those with one or more complications of diabetes; control subjects (n = 162) were those with no evidence of any complication. We measured NT-proBNP levels by a two-site sandwich electrochemiluminescence immunoassay and investigated their associations with complications.

RESULTS

Mean NT-proBNP levels were significantly higher in case than in control subjects. In logistic regression analyses, NT-proBNP values >26.46 pg/mL were independently associated with a 2.56-fold increased risk of all complications. Odds ratios of CVD (3.95 [95% CI 1.26-12.35]), nephropathy (4.38 [1.30-14.76]), and distal symmetrical polyneuropathy (4.32 [1.41-13.23]) were significantly increased in patients with NT-proBNP values in the highest quartile (>84.71 pg/mL), independently of renal function and known risk factors. These associations were no longer significant after inclusion of TNF-α into the model.

CONCLUSIONS

In this large cohort of type 1 diabetic subjects, we found an association between NT-proBNP and diabetic micro- and macrovascular complications. Our results suggest that the inflammatory cytokine TNF-α may be involved in this association.

Impact of the look AHEAD intervention on NT-pro brain natriuretic peptide in overweight and obese adults with diabetes

Look AHEAD (Action for Health in Diabetes) is a randomized trial determining whether intensive lifestyle intervention (ILI) aimed at long-term weight loss and increased physical fitness reduces cardiovascular morbidity and mortality in overweight and obese individuals with type 2 diabetes compared to control (diabetes support and education, DSE). We investigated the correlates of N-terminal pro-brain natriuretic peptide (NT-proBNP), a biomarker associated with heart failure (HF) risk, in a subsample from 15 of 16 participating centers and tested the hypothesis that ILI decreased NT-proBNP levels. Baseline and 1-year blood samples were assayed for NT-proBNP in a random sample of 1,500 without, and all 628 with, self-reported baseline CVD (cardiovascular disease) (N = 2,128). Linear models were used to assess relationships that log-transformed NT-proBNP had with CVD risk factors at baseline and that 1-year changes in NT-proBNP had with intervention assignment. At baseline, the mean (s.d.) age, BMI, and hemoglobin A(1c) (HbA(1c)) were 59.6 (6.8) years, 36.0 kg/m(2) (5.8), and 7.2% (1.1), respectively. Baseline geometric mean NT-proBNP was not different by condition (ILI 53.3 vs. DSE 51.5, P = 0.45), was not associated with BMI, and was inversely associated with HbA(1c). At 1 year, ILI participants achieved an average weight loss of 8.3% compared to 0.7% in DSE. At 1 year, NT-proBNP levels increased to a greater extent in the intervention arm (ILI +21.3% vs. DSE +14.2%, P = 0.046). The increased NT-proBNP associated with ILI was correlated with changes in HbA(1c), BMI, and body composition. In conclusion, among overweight and obese persons with diabetes, an ILI that reduced weight was associated with an increased NT-proBNP.

Predictive value of serum NT-proBNP levels in type 2 diabetic people with diabetic nephropathy

OBJECTIVE

The serum N-terminal fragment of pro brain natriuretic peptide (NT-proBNP) level in type 2 diabetic subjects with or without diabetic nephropathy (DN) is still unclear. We aimed to evaluate the relationship between serum NT-proBNP levels and different stages of diabetic nephropathy, and identify probable factors predicting serum NT-proBNP level.

SUBJECTS AND METHODS

This cross-sectional study included 20 normoalbuminuric (Group-I), 28 microalbuminuric (Group-II), 20 macroalbuminuric type 2 diabetic patients (Group-III), and 20 healthy volunteers (Group-IV). Serum NT-proBNP levels were measured with highly sensitive and specific immunoassay.

RESULTS

Mean NT-proBNP levels were 32 ± 55, 91 ± 95, 331 ± 297, 42 ± 34 pg/ml for Groups I-IV, respectively. When patients with LVH were excluded, mean logNT-proBNP was still significantly higher in Group-III than all other groups. The three diabetic groups were similar in age, BMI, HbA1c, fasting serum glucose, and GFR. In a multivariate linear regression model, adjusting for factors significantly correlated with NT-proBNP levels, the patient group, presence of LVH, and hemoglobin remained as an independent predictor of serum NT-proBNP. These variables explained 68% of the variability of NT-proBNP (adjusted R(2)=0.683).

CONCLUSIONS

Mean serum NT-proBNP level of macroalbuminuric diabetic patients was higher than normoalbuminuric and microalbuminuric diabetic patients, and healthy control subjects even after exclusion of LVH. NT-proBNP may be a useful and predictive marker of diabetic nephropathy.

Association of myocardial fibrosis, B-type natriuretic peptide, and cardiac magnetic resonance parameters of remodeling in chronic ischemic cardiomyopathy

The left ventricular (LV) scar size detected by cardiac magnetic resonance (CMR) imaging in ischemic cardiomyopathy (IC) has been correlated with mortality. However, the associations among myocardial fibrosis, ventricular geometry, and physiologic measures of myocardial performance remain to be defined. A retrospective analysis of patients with stable chronic IC (LV ejection fraction ≤50%) who underwent CMR imaging from 2004 to 2010 and had plasma B-type natriuretic peptide (BNP) measured within 14 days of the CMR study was undertaken. A total of 38 patients met the criteria (mean age 66 ± 10 years; 31 men [82%]). The duration of IC was 67 ± 69 months. The CMR characteristics included LV dilation (LV end-diastolic dimension 62 ± 8 mm) and severe systolic dysfunction (LV ejection fraction 28 ± 11%). The average quantitated myocardial fibrosis was 20 ± 12% of the LV mass. When stratified by fibrotic mass, increased myocardial scar size was associated with increased LV cavity size (p = 0.007), lower LV ejection fraction (p = 0.04), and higher BNP (p = 0.013). In comparison, when stratified by median BNP (475 pg/ml), an elevated BNP level was associated, not only with LV size, function, and degree of fibrosis, but also with increased meridional wall stress (p = 0.002) and worse New York Heart Association functional class (p = 0.006). In conclusion, in chronic IC, quantitated myocardial fibrosis is associated with CMR structural and functional LV abnormalities. Elevated BNP levels are related to high-risk structural and functional CMR abnormalities and wall stress and functional status. Myocardial fibrosis appears to be related to plasma BNP through the processes of ventricular remodeling.

Prognostic Value of NT-proBNP at Rest and Peak Exercise in Patients With Impaired Left Ventricular Function

We aimed to identify whether N-terminal fragment of pro-brain natriuretic peptide (NT-proBNP) at peak exercise can provide incremental clinical information over resting levels. A total of 90 patients with systolic heart failure were prospectively studied. Levels of plasma NT-proBNP were assessed at rest and at peak exercise during a cardiopulmonary exercise test. Patients were followed-up for 30 ± 10 months. Levels of NT-proBNP at baseline and peak exercise were significantly correlated with left ventricular ejection fraction ([LVEF] r = −.629, P < .001 and r = −.630, P < .001, respectively) and peak oxygen uptake ([Vo2] r = −.752, P < .001 and r = −.740, P < .001, respectively). Levels of plasma NT-proBNP at peak exercise demonstrated similar predictive ability for the detection of patients with low peak Vo2 and LVEF <28%. Levels of plasma NT-proBNP can detect low-functional class patients and patients who may be the candidates for heart transplantation with high sensitivity and specificity. At baseline and peak exercise, NT–proBNP demonstrates similar prognostic and predictive ability.

Sensitivity and specificity of NT-proBNP to detect heart failure at post mortem examination

NT-proBNP, a marker of cardiac failure, has been shown to be stable in post mortem samples. The aim of this study was to assess the accuracy of NT-proBNP to detect heart failure in the forensic setting. One hundred sixty-eight consecutive autopsies were included in the study. NT-proBNP blood concentrations were measured using a chemiluminescent immunoassay kit. Cardiac failure was assessed by three independent forensic experts using macro- and microscopic findings complemented by information about the circumstances of body discovery and the known medical story. Area under the receiving operator curve was of 65.4% (CI 95%, from 57.1 to 73.7). Using a standard cut-off value of >220 pg/mL for NT-proBNP blood concentration, heart failure was detected with a sensitivity of 50.7% and a specificity of 72.6%. NT-proBNP vitreous humor values were well correlated to the ones measured in blood (r (2) = 0.658). Our results showed that NT-proBNP can corroborate the pathological findings in cases of natural death related to heart failure, thus, keeping its diagnostic properties passing from the ante mortem to the post mortem setting. Therefore, biologically inactive polypeptides like NT-proBNP seem to be stable enough to be used in forensic medicine as markers of cardiac failure, taking into account the sensitivity and specificity of the test.

Prognostic value of plasma N-terminal pro-B-type natriuretic peptide concentration in patients with normal and impaired left ventricular systolic function undergoing surgery for abdominal aortic aneurysm

INTRODUCTION

Implantation of an aortic-bifemoral prosthesis is characterised by a high (> 5%) rate of perioperative cardiovascular events. The main aim of the study is to demonstrate the usefulness of the determination of NT-proBNP concentration as a method of risk stratification of left ventricular dysfunction in patients subjected to surgery for aortic-bifemoral prosthesis implantation.

MATERIAL AND METHODS

Forty consecutive patients were examined and subjected to aortic-bifemoral prosthesis implantation. The examined patients were divided into two groups: 1) with normal left ventricular systolic function and EF ≥ 58% (group I), 2) with left ventricular systolic dysfunction and EF < 58% (group II).

RESULTS

In group I the median EF before surgery was 69.5% and the concentration of NT-proBNP 141.5 pg/ml. On day 7 after surgery respective values were EF 65.5%, NT-proBNP 498.55 pg/ml. In group II the median EF before surgery was 54%, and NT-proBNP concentration 303.9 pg/ml.

CONCLUSIONS

The concentration of plasma NT-proBNP before surgery well correlated with left ventricular ejection fraction. The values of NT-proBNP > 303.9 pg/ml strongly correlated with increased risk of left ventricular systolic dysfunction after surgery and they seem to have high prognostic value for the occurrence of cardiovascular events in this group of patients. The determination of NT-proBNP level on day 7 after surgery strongly correlated with the decrease of left ventricular ejection fraction in patients after the prosthesis implantation. It is a valuable diagnostic and prognostic factor of circulatory system efficiency before making a decision to discontinue hospitalization.

Natriuretic Peptide testing in primary care

The incidence, as well as the morbidity and mortality associated with heart failure (HF) continue to rise despite advances in diagnostics and therapeutics. A recent advance in the diagnostic and therapeutic approach to HF is the use of natriuretic peptide (NP) testing, including both B-type natriuretic peptide (BNP) and its amino terminal cleavage equivalent (NT-proBNP). NPs may be elevated at an early stage among those with symptoms as well among those without. The optimal approach for applying NP testing in general populations is to select the target population and optimal cut off values carefully. Superior diagnostic performance is observed among those with higher baseline risk (such as hypertensives or diabetics). As well, unlike for acute HF, the cut off value for outpatient testing for BNP is 20-40 pg/mL and for NTproBNP it is 100-150 ng/L. In symptomatic primary care patients, both BNP and NT-proBNP serve as excellent tools for excluding HF based on their excellent negative predictive values and their use may be cost effective. Among those with established HF, it is logical to assume that titration of treatment to achieve lower NPs levels may be advantageous. There are several ongoing trials looking at that prospect.

Age-dependent values of N-terminal pro-B-type natriuretic peptide are superior to a single cut-point for ruling out suspected systolic dysfunction in primary care

AIMS

The study evaluated the use of age-related decision limits for N-terminal pro-B-type natriuretic peptide (NT-proBNP), for ruling out suspected systolic dysfunction in symptomatic patients in primary care, compared with the present standards.

METHODS AND RESULTS

Data were obtained from 5508 patients from 10 studies in the UK, New Zealand, Europe, and USA. All have had NT-proBNP analysis and echocardiography. The median age was 62 years (range 18-100 years) with a prevalence of reduced left ventricular systolic function (left ventricular ejection fraction < or =40%) of 18%. In a receiver operating characteristic curve analysis, overall area under the curve (AUC) was 0.89. When looking at different age groups, AUC was highest (0.95) for <50 years, intermediate (0.90) for 50-75 years, and lowest (0.82) for >75 years. Using optimized decision limits, sensitivity, specificity, and negative predictive values (NPVs) were: <50 years (50 ng/L): 99.2, 57.2, and 99.7%; 50-75 years (75 ng/L): 95.9, 51.0, and 96.8%; and >75 years (250 ng/L): 87.9, 53.7, and 92.4%, respectively. Using only a single decision value (125 ng/L for all ages) gave sensitivities of 89.1, 91.9, and 94.3%; specificities of 84.0, 69.1, and 29.3% and NPVs of 97.7, 97.6, and 93.4%. A decision value of 400 ng/L for all ages gave much lower sensitivities.

CONCLUSION

In a large population of patients in primary care, the use of age-stratified NT-proBNP decision limits considerably improves performance over current standards, with an excellent NPV for exclusion of reduced left ventricular systolic function.

Diagnostic accuracy of emergency Doppler echocardiography for identification of acute left ventricular heart failure in patients with acute dyspnea: comparison with Boston criteria and N-terminal prohormone brain natriuretic peptide

OBJECTIVES

Echocardiography is a fundamental tool in the diagnosis of acute left ventricular heart failure (aLVHF). However, a consultative exam is not routinely available in every emergency department (ED). The authors investigated the diagnostic performance of emergency Doppler echocardiography (EDecho) performed by emergency physicians (EPs) for the diagnosis of aLVHF in patients with acute dyspnea.

METHODS

A convenience sample of acute dyspneic patients was evaluated. For each patient, the Boston criteria score for heart failure was calculated, and N-terminal prohormone brain natriuretic peptide (NT-proBNP) and EDecho were contemporaneously performed. Four investigators, after a limited echocardiography course, performed EDechos and evaluated for a "restrictive" pattern on pulsed Doppler analysis of mitral inflow and reduced left ventricular (LV) ejection fraction. The final diagnosis, established after reviewing all patient clinical data except NT-proBNP and EDecho results, served as the criterion standard.

RESULTS

Among 145 patients, 64 (44%) were diagnosed with aLVHF. The median time needed to perform EDecho was 4 minutes. Pulsed Doppler analysis was feasible in 125 patients (84%). The restrictive pattern was more sensitive (82%) and specific (90%) than reduced LV ejection fraction and more specific than the Boston criteria and NT-proBNP for the diagnosis of aLVHF. Considering noninterpretable values of the restrictive pattern and uncertain values ("gray areas") of Boston criteria (4 < Boston criteria score < 7) and of NT-proBNP (300 < NT-proBNP < 2,200 pg/mL) as false results, the accuracy of the restrictive pattern in the overall population was 75%, compared with accuracy of 49% for both NT-proBNP and Boston criteria.

CONCLUSIONS

EDecho, particularly pulsed Doppler analysis of mitral inflow, is a rapid and accurate diagnostic tool in the evaluation of patients with acute dyspnea.

Comparative impact of scintigraphic parameters and B-type natriuretic peptide for the prediction of major cardiac events in the QGS-prognostic value in the elderly (Q-PROVE) study

BACKGROUND

Although B-type natriuretic peptide (BNP) has emerged as an important predictor for cardiac events, its effect on scintigraphic parameters is unknown.

METHODS AND RESULTS

The Q-PROVE study is a multicenter study to evaluate the prognostic value of ECG-gated SPECT in 175 Japanese elderly patients. In addition, BNP was assessed in 102 patients. Outcome assessment included cardiac events and noncardiac deaths. Twelve elderly patients (12%) had increased BNP >130 pg/ml. The summed stress score (SSS) was greater in patients with increased BNP than in those with normal BNP. Kaplan-Meier survival estimation indicated event-free survival rates at 3 years of 83%, 78%, 88%, 80%, respectively, in patients with BNP >130 pg/ml, SSS >or=7, summed difference score (SDS) >or=2, and dilated end-diastolic volume (EDV), but 98%, 98%, 100%, 94% in those with BNP <or=130 pg/ml, SSS <7, SDS <2 and normal EDV (P=0.006, P=0.005, P=0.0008, P=0.01). Multivariate analysis demonstrated that an SDS was the only independent predictor for subsequent cardiac events (hazard ratio =4.0, P=0.04).

CONCLUSIONS

Although BNP may have similar prognostic value to gated SPECT volumetric measurements in elderly patients with known or suspected coronary artery disease, myocardial ischemia as documented by SPECT is still indispensable for detecting high-risk patients compared with BNP alone.

Nt-proBNP in haemodialysis patients: a preliminary study

OBJECTIVE

N-terminal pro-brain natriuretic peptide (Nt-proBNP) is a marker of left ventricular function. Although many factors can increase left ventricular dysfunction in haemodialysis patients, the role of Nt-proBNP is uncertain.

MATERIAL AND METHODS

Serum concentrations of Nt-proBNP and troponin T were measured by electrochemiluminescence and C-reactive protein by immunoturbidimetry in 52 dialysis patients followed-up for 36 months.

RESULTS

Nt-proBNP correlated (p<0.05) with time on haemodialysis (rho=0.345), left ventricular mass index (r=0.596), troponin T level (r=0.605) and age (r=0.296). Patients with a history of heart disease showed higher levels of Nt-proBNP (median; minimum-maximum ngl/L) (15,571; 1,553-209,451) than those without (4,535; 751-115,078) (p<0.01). Sensitivity and specificity of Nt-proBNP in the detection of left ventricular dysfunction (ventricular ejection fraction < 45%) were 1.0 and 0.782, respectively. In the univariate analysis, patients with Nt-proBNP levels > or = 33,314 ng/L, CRP > or = 5 mg/L or troponin T > or = 0.1 microg/L had poorer probabilities of 1-year, 2-year and 3-year survival than patients with lower levels. Unfavourable prognostic factors in the multivariate analysis were CRP > 5 mg/L and Tn T > 0.1 microg/L.

CONCLUSIONS

Nt-proBNP showed good diagnostic performance for detecting left ventricular dysfunction and was an important predictor of mortality in haemodialysis patients in the univariate analysis. In the multivariate analysis, Nt-proBNP lost its prognostic value, whereas for CRP and Tn T it was maintained.

Clinical Use and Pathogenetic Basis of Laboratory Tests for the Evaluation of Primary Arterial Hypertension

This review focuses on the laboratory biochemical tests that are useful in the diagnostic approach to the hypertensive patient. A "minimal" diagnostic laboratory work-up, including a small number of tests that are simple and relatively inexpensive, is first described. Because these tests provide basic information on the presence of major cardiovascular (CV) risk factors and target organ damage, and might give some clues to the presence of a secondary form of hypertension (HT), they should be performed on all patients presenting with HT. Other tests that are aimed at assessing the overall CV risk, a major determinant of prognosis that dictates the therapeutic strategy in the individual HT patient, are then discussed. They allow identification of major CV risk factors and associated clinical conditions which, if present, lead to a substantial change of therapeutic strategy. The role of C-reactive protein as a marker of atherosclerosis and its predictive value for CV events are also discussed. Finally, a section is devoted to tests that are currently confined to research purposes, such as markers of endothelial function including endothelin-1, homocysteine and genetic analysis.

N-terminal pro-brain natriuretic peptide in the elderly with myocardial infarction

BACKGROUND

The myocardial infarction (MI) results in the change of the levels of N-terminal pro-brain natriuretic peptide (NT-proBNP) in blood. In addition, attention is paid to the dependence of NT-proBNP levels on the patients' age. However, the behavior of natriuretic peptide levels has not been recognized well enough in the elderly with MI treated with invasive methods.

HYPOTHESIS

The aim of the study was to estimate the effect of age on NT-proBNP levels in patients with first MI, and treated with primary percutaneous coronary intervention (PCI) with complete coronary revascularization.

METHODS

One hundred and sixty-one consecutive patients with first ST-elevation MI, and treated with primary PCI with stent implantation (occlusion in infarct-related artery was the patient's only lession) were included. Determination of NT-proBNP level and echocardiography were performed on the 4th-5th day of MI.

RESULTS

Thirty-seven patients (23%) aged>or=65 y were considered as a study group. The NT-proBNP levels were nearly 4-fold higher in older patients than in younger patients. Only systolic and diastolic dysfunction, mitral regurgitation, troponin T levels, and glomerular filtration rate (GFR) were independent risk factors of the occurrence of elevated NT-proBNP concentration above median.

CONCLUSIONS

The patients' age was not a factor independently affecting the increase of NT-proBNP level above the median in patients with first MI and treated successfully with primary PCI. Independently associated elevated levels of NT-proBNP were as follows: presence of diastolic dysfunction, mitral regurgitation, left ventricular systolic dysfunction, troponin T concentration, and GFR.

Effects of cigarette smoking on heart rate variability and plasma N-terminal pro-B-type natriuretic peptide in healthy subjects: is there the relationship between both markers?

BACKGROUND

Cigarette smoking increased the risk of acute cardiac events related with endothelial dysfunction and increased sympathetic activity. Impaired autonomic nervous activity is recognized as a considerable symptom of cardiac dysfunction and is strongly associated with increased risk overall mortality.

METHODS

A total of 75 healthy habitual smokers (40 female, 35 male, mean age 36.5 +/- 8.5 years), and 73 non-smokers subjects (45 female, 28 male, mean age 34.6 +/- 7.2 years) were studied. LF and LF/HF ratio were significantly higher in smokers than in non-smokers. On the contrary, SDNN, SDANN, RMSSD, and HF values were lower in smokers compared to those in non-smokers. Not the duration of smoking but the number of cigarettes smoked per day was correlated with the HRV parameters and NT-pro BNP. Furthermore, the average levels of NT-pro BNP were found to be positively correlated with LF, LF/HF and inversely correlated with SDNN, SDANN, RMSSD and HF.

RESULTS

As a result, smoking impaires sympathovagal balance and decreases the heart rate variability in healthy subjects. And even a one cigarette smoking leads to overt sympathetic excitation. Furthermore, smoking results in an increase in NT-proBNP levels and the changes in adrenergic nervous system and NT-proBNP levels are well correlated.

CONCLUSION

These findings could contribute to the higher rate of cardiovascular events in smokers.

N-terminal B-type natriuretic peptide levels in pediatric patients with congestive heart failure undergoing cardiac surgery

OBJECTIVES

The objectives of this study were to measure circulating N-terminal B-type natriuretic peptide levels in pediatric patients undergoing surgical repair of congenital heart lesions with left ventricular volume overload and to determine whether presurgical and immediate postoperative N-terminal B-type natriuretic peptide levels could predict patient outcomes after surgical intervention.

METHODS

Thirty-eight children aged 1 to 36 months undergoing surgical repair of cardiac lesions with left ventricular volume overload were studied. Plasma N-terminal B-type natriuretic peptide levels were measured preoperatively and at 2, 12, 24, 48, and 72 hours after surgical intervention and were assessed for their predictive value of postoperative outcomes. Plasma N-terminal B-type natriuretic peptide levels were also measured in 34 similarly aged healthy children.

RESULTS

Patient preoperative N-terminal B-type natriuretic peptide levels were significantly higher than those of healthy control subjects (3085 +/- 4046 vs 105 +/- 78 pg/mL). Preoperative N-terminal B-type natriuretic peptide levels correlated with the complexity of surgical repair, as measured by cardiopulmonary bypass time (r = 0.529, P < .001), and with postoperative measures, including fractional inhaled oxygen requirements registered at 12 hours (r = 0.443, P = .005) and duration of mechanical ventilation (r = 0.445, P = .005). Plasma N-terminal B-type natriuretic peptide levels increased 5-fold within 12 hours after cardiopulmonary bypass (14,685 +/- 14,317 pg/mL). Multivariable regression analysis showed that the preoperative N-terminal B-type natriuretic peptide level was a significant predictor of duration of intensive care unit stay (P = .02) and that the peak postoperative N-terminal B-type natriuretic peptide level was a significant predictor of the intensity of overall medical management, as assessed by using the therapeutic intervention scoring system (P = .01).

CONCLUSION

Plasma N-terminal B-type natriuretic peptide levels measured preoperatively and postoperatively can be a prognostic indicator in the management of the pediatric patient after surgical intervention for congenital heart repair.

Isolated diastolic dysfunction--diagnostic value of tissue Doppler imaging, colour M-mode and N-terminal pro B-type natriuretic peptide

INTRODUCTION

For diagnosis of diastolic dysfunction of the left ventricle (DDF), measurement of relaxation velocity (V(R)) by tissue Doppler imaging (V(R)), flow propagation velocity of transmitral inflow (v(p)) as well as the measurement of serum levels of N-terminal pro b-type natriuretic peptide (NT-proBNP) compete with the standard echocardiographic DDF-measures because of several disadvantages of the latter.

METHODS

We examined the diagnostic value of method 1, 2 and NT-proBNP in 120 patients with echocardiographic-proven DDF and in 20 patients without. Patients were classified according to the DDF-stage by standard echocardiographic parameters (transmitral E/A-ratio, deceleration time, isovolumetric relaxation time) into stage I, II and III and furthermore subdivided by the presence of dyspnoea.

RESULTS

V(R) and v(p) were significantly lower in patients with DDF than in patients without DDF, with no difference between the various DDF stages. Symptomatic patients showed a trend to a lower V(R). NT-proBNP was elevated in patients with DDF: Symptomatic patients with a DDF at stage I and patients with a DDF at stage II and III independent of the presence of symptoms had elevated NT-proBNP levels.

CONCLUSION

All three methods tested identified patients with DDF. NT-proBNP and v(p) were able to discriminate between symptomatic and asymptomatic patients.

Lipid and inflammatory markers for the prediction of coronary artery disease: A multi-marker approach

BACKGROUND

Many studies have investigated the clinical accuracy of single lipid and inflammatory markers. In contrast, few have evaluated their potential for the detection of CAD using a multi-marker approach.

METHODS

The concentrations of lipid, lipoproteins, apolipoproteins, high sensitivity C-reactive protein (hs-CRP) and fibrinogen were measured by standard laboratory methods. Apolipoprotein (a) [apo(a)] phenotyping was performed by sodium dodecylsulphate-gel electrophoresis and immunoblotting. The lipid tetrad index (LTI) and the lipid pentad index (LPI) were calculated. Clinical accuracy of the examined parameters, indexes and a logistic regression model was assessed using receiving operative characteristic (ROC) curve analysis.

RESULTS

Logistic regression analysis indicated that non-HDL-c, hs-CRP, HDL-c and Lp(a) were significant independent predictors for CAD. The AUC for this model (0.802) was higher than AUCs for any single marker or index tested.

CONCLUSIONS

We conclude that the performance of a logistic regression model for CAD prediction warrants its use in clinical practice.

N-Terminal Prohormone Brain Natriuretic Peptide as a Marker for Detecting Low Functional Class Patients and Candidates for Cardiac Transplantation: Linear Correlation With Exercise Tolerance

BACKGROUND

N-terminal prohormone brain natriuretic peptide (NT Pro BNP) plasma levels have been associated with indices of left ventricular (LV) function and aerobic capacity in heart failure. The aim of our study was to use NT Pro BNP for the prediction of low functional class patients and also to detect candidates for cardiac transplantation.

METHODS

We studied 100 patients with impaired left ventricular (LV) function. Mean LV ejection fraction (LVEF) was 35% +/- 9%. Blood samples for NT Pro BNP assessment were taken at baseline during treadmill exercise testing. LV cavity diameters, left atrial size, and LVEF were measured by echocardiography.

RESULTS

Plasma levels of NT Pro BNP correlated significantly with peak oxygen consumption (VO(2)) values (r = -0.77, p < 0.001). LVEF correlated well with NT Pro BNP (r = -0.67, p < 0.001). NT Pro BNP plasma levels correlated strongly with New York Heart Association functional class (r = 0.70, p < 0.001). NT Pro BNP values exceeding 335 pg/ml showed 83% sensitivity and 76% specificity for detecting VO(2) values below 20 ml/kg/min (area under the curve [AUC] = 86%, p < 0.001). NT Pro BNP plasma levels exceeding 1,190 pg/ml showed 83% sensitivity and 86% specificity for detecting VO(2) of less than 14 ml/kg/min (AUC = 90%, p < 0.001). NT Pro BNP plasma levels exceeding 1,610 pg/ml showed 87% sensitivity and specificity 82% for detecting VO(2) of less than 10 ml/kg/min (AUC = 90%, p < 0.001). NT Pro BNP plasma levels exceeding 680 pg/ml showed 91% sensitivity and 73% specificity for detecting LVEF of less than 28% (AUC = 86%, p < 0.001).

CONCLUSIONS

NT Pro BNP plasma levels correlate both with LVEF and aerobic capacity, can predict low functional cardiopulmonary exercise capacity in patients with impaired left ventricular function, and are useful for detecting candidates for cardiac transplantation.

N-terminal pro-B-type natriuretic peptide as a diagnostic test for ventricular dysfunction in patients with coronary disease: data from the heart and soul study

BACKGROUND

N-terminal pro-B-type natriuretic peptide (NT-proBNP) testing is useful for diagnosing acute decompensated heart failure. Whether NT-proBNP can be used to detect ventricular dysfunction in patients with stable coronary heart disease (CHD) and no history of heart failure is unknown.

METHODS

We measured NT-proBNP levels and performed transthoracic echocardiography in 815 participants from the Heart and Soul Study, who had stable CHD and no history of heart failure. We hypothesized that NT-proBNP concentrations lower than 100 pg/mL would rule out ventricular dysfunction and concentrations higher than 500 pg/mL would identify ventricular dysfunction. We calculated sensitivities, specificities, likelihood ratios, and areas under the receiver operating characteristic curves for NT-proBNP as a case-finding instrument for systolic and diastolic dysfunction.

RESULTS

Of the 815 participants with no history of heart failure, 68 (8%) had systolic dysfunction defined as a left ventricular ejection fraction of 50% or lower. Of the 730 participants for whom the presence or absence of diastolic dysfunction could be determined, 78 (11%) had diastolic dysfunction defined as a pseudonormal or restrictive filling pattern. The overall area under the receiver operating characteristic curve for detecting systolic or diastolic dysfunction was 0.78 (95% confidence interval, 0.74-0.82). Likelihood ratios were 0.28 for NT-proBNP concentrations lower than 100 pg/mL, 0.95 for concentrations between 100 and 500 pg/mL, and 4.1 for concentrations higher than 500 pg/mL. A test result lower than 100 pg/mL reduced the probability of ventricular dysfunction from a pretest probability of 18% to a posttest probability of 6%. A test result higher than 500 pg/mL increased the probability of ventricular dysfunction from a pretest probability of 18% to a posttest probability of 47%. A test result between 100 and 500 pg/mL did not change the probability of ventricular dysfunction.

CONCLUSION

In patients with stable CHD and no history of heart failure, NT-proBNP levels lower than 100 pg/mL effectively rule out ventricular dysfunction, with a negative likelihood ratio of 0.28.

Cardiovascular hemodynamics and umbilical artery N-terminal peptide of proB-type natriuretic peptide in human fetuses with growth restriction

OBJECTIVE

To test our hypothesis that human fetal N-terminal peptide of proB-type natriuretic peptide (NT-proBNP) secretion is increased in proportion to the severity of fetal cardiovascular compromise in intrauterine growth restriction.

METHODS

This prospective cross-sectional study consisted of 42 growth-restricted fetuses who underwent Doppler ultrasonographic examination of cardiovascular hemodynamics within 7 days before delivery. Group 1 fetuses (n = 13) had normal umbilical artery (UA) velocimetry. Group 2 fetuses (n = 15) had abnormal UA and normal ductus venosus (DV) velocimetry. In Group 3 fetuses (n = 14), both UA and DV velocimetries were abnormal. At delivery, an UA blood sample was obtained for assessment of NT-proBNP. Normal values for UA NT-proBNP were determined in 49 neonates (control group) with uncomplicated pregnancy and delivery.

RESULTS

Group 3 fetuses demonstrated greater (P < 0.05) UA and descending aorta pulsatility indices (PIs) and greater DV, left hepatic vein (LHV) and inferior vena cava PIs for veins (PIVs) than fetuses in Groups 1 and 2. Weight-indexed cardiac outputs and ventricular ejection forces were similar among the groups. Group 3 fetuses had higher (P < 0.05) UA NT-proBNP concentration than fetuses in Groups 1 and 2. In the control group, the 95(th) percentile value of UA NT-proBNP was 518 pmol/L. In Group 3, 13/14 neonates demonstrated abnormal UA NT-proBNP levels. The corresponding incidences were 4/13 and 7/15 in Groups 1 and 2. Significant positive correlations were found between UA, DV and LHV PIVs and UA NT-proBNP concentrations.

CONCLUSION

In human fetal growth restriction, increased cardiac afterload and pulsatility in DV blood velocity waveform pattern are associated with elevated UA NT-proBNP concentrations.

A multi-marker approach for the prediction of adverse events in patients with acute coronary syndromes

BACKGROUND

Cardiac troponin T (cTnT), high sensitivity C-reactive protein (hs-CRP) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) have emerged as strong predictors of adverse events among patients presenting with acute coronary syndromes (ACS). We evaluated the prognostic performance of each of these markers, individually, and in combination in patients presenting to the emergency department (ED) with ACS symptoms.

METHODS

Serum samples were obtained from 422 consenting patients presenting to the ED with symptoms of acute coronary syndrome (ACS) and subsequently tested for cTnT, NT-proBNP, myoglobin, CK-MB, and hs-CRP. Adverse events (AEs) occurring within 30 days (death, myocardial infarction, unstable angina and the need for revascularization procedures) were recorded and ROC curves were constructed.

RESULTS

AEs occurred in 42 patients (10%). Relative risk, cut-off, and predictive values for each biomarker were determined statistically, with the exception of cTnT, where the concentration meeting the 99th percentile of a healthy population with a 10% coefficient of variation (0.03 ng/ml) was used. These cut-off values, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and relative risk (RR) were calculated. Sensitivity and RR for a panel of cTnT and NT-proBNP were 78.6% (66.2-91.0) and 4.7 (2.3-9.5), respectively.

CONCLUSIONS

If used alone, cTnT appeared to have greater prognostic value when compared to hs-CRP, NT-proBNP, myoglobin or CK-MB. The combination of cTnT and NT-proBNP performed better than the combination of cTnT and hs-CRP. When cTnT, NT-proBNP and hs-CRP were used as a panel, there was no significant improvement in prognostic performance over using cTnT and NT-proBNP together. Thus, in patients with suspected ACS, the measurement of both cTnT and NT-proBNP may have enhanced prognostic performance over using either marker in isolation.

The diagnostic and prognostic value of brain natriuretic peptides in adults with a systemic morphologically right ventricle or Fontan-type circulation

BACKGROUND

In acquired heart disease, brain natriuretic peptide (BNP) and N-Terminal pro-brain natriuretic peptide (NT-proBNP) are increasingly used as diagnostic and prognostic markers. In adult congenital heart disease, the abnormal anatomy and physiology complicate assessment of cardiac function. We studied the clinical correlates of measurement of natriuretic peptides (NP) in adults with a right ventricle in the systemic position or with Fontan-type physiology.

METHODS

A prospective longitudinal study (follow up time 23+/-13 months, mean+/-S.D.) was conducted in a specialised centre on 61 patients (age 26+/-8 years; NYHA class 1.5+/-0.6) including Senning/Mustard corrected transposition, congenitally corrected transposition and Fontan/total cavopulmonary connection. Plasma NP concentration was compared with NYHA class, exercise capacity and echocardiographically determined systemic systolic ventricular function.

RESULTS

Neurohormone concentrations were generally elevated (mean=290% of upper reference limit) and related to NYHA class (P<0.001, NYHA I vs. II-IV). No clinically significant relationship to ventricular function or exercise capacity was found however. An NP measurement could not predict the future course of the disease in terms of functional status or ventricular function.

CONCLUSION

In contrast to patients with acquired heart disease, measurement of NP seems to have low clinical value in adults with a right ventricle in the systemic position or with Fontan-type physiology.

Maximum longitudinal relaxation velocity of the left ventricle: its clinical value and relationship with NT-proBNP plasma levels in heart failure

BACKGROUND

M-mode recordings of the mitral annulus to measure the maximum ascending velocity during early diastole as an expression of maximum longitudinal relaxation velocity of the left ventricle (RVm) can be used as an index of left ventricular (LV) diastolic function. The purpose of this study was to determine the relationship of RVm with LV functional parameters in patients with heart failure, with N-terminal pro-brain natriuretic peptide (NT-proBNP) plasma levels, and with their functional classification.

METHODS AND RESULTS

RVm was recorded in 97 patients by M-mode echocardiography. Patients were classified according to the New York Heart Association (NYHA) and the concentration of NT-proBNP was determined. Patients with ejection fraction (EF)>40 showed a significant correlation between RVm and mitral annulus motion (MAM), mitral flow propagation velocity, E/A, age, deceleration time (DT), and NT-proBNP. In patients with EF<or=40, RVm correlated significantly with MAM, EF, and NT-proBNP. RVm values were higher in NYHA class I compared to II and III, P<0.0001.

CONCLUSIONS

RVm correlates better with functional parameters in patients with EF>40, though its relationship with NT-proBNP both in patients with EF>or<or=40 is to be highlighted. Correlation between RVm and NT-proBNP is influenced by age, EF, and E/A, whereas in patients with EF>40 it is influenced only by age. RVm values showed a significant decrease in NYHA class II and III.

Predictive value of the serum level of N-terminal pro-brain natriuretic peptide and high-sensitivity C-reactive protein in left ventricular remodeling after acute myocardial infarction

This study was designed to measure the correlation between left ventricular (LV) remodeling 3 months after successful reperfusion therapy, and the levels of serum N-terminal pro-brain natriuretic peptide (NT-proBNP) and high-sensitivity C-reactive protein (hs-CRP) at 3 days after acute myocardial infarction (AMI), and to determine the predictive levels of NT-proBNP and hs-CRP for LV remodeling. A total of 106 patients with first AMI were included in this study. Each patient was examined by echocardiography (ECG) on the third day and third month after AMI, and LV remodeling was determined by the difference in the LEV end-diastolic volume (LVEDV) between the third day and the third month. Serum NT-proBNP and hs-CRP level were measured 3 days after AMI. Then the correlation between the 3-months change in LVEDV and the levels of serum NT-proBNP or hs-CRP was determined. In addition, sensitivity and specificity were calculated with a receiver operating characteristic (ROC) curve to identify correspondence with LV remodeling (defined as the change rate of LVEDV >20%). Our results showed that the correlation coefficients with the change of LVEDV were 0.706 for serum NT-pro BNP (P<0.001) and 0.596 for hs-CRP (P<0.05). With a cutoff value of 0.2, the area under the ROC curve (AUC) was 0.894 for NT-proBNP and 0.825 for hs-CRP. Although the AUC did not statistically differ between NT-proBNP and hs-CRP, NT-proBNP is more effective than serum hs-CRP as a marker to predict LV remodeling.

Atrial and ventricular volume and function evaluated by magnetic resonance imaging in patients with persistent atrial fibrillation before and after cardioversion

Atrial fibrillation (AF) is the most common cardiac arrhythmia and 25% of those >40 years old will experience AF. Left atrial size and left ventricular function are independently related to cardiovascular morbidity and mortality. Our aim was to evaluate cardiac volume and function using magnetic resonance imaging in patients with persistent AF and to describe the changes after cardioversion (CV). Sixty consecutive patients with persistent AF and 19 healthy volunteers had cardiac volumes evaluated by cinematographic breath-hold magnetic resonance imaging. Patients with AF were evaluated before CV and at 1, 30, and 180 days after CV, if still in sinus rhythm. All atrial and ventricular volumes and left ventricular mass decreased and ejection fractions increased significantly after CV (p <0.0001 for all variables). Atrial and ventricular diastolic volumes increased significantly the day after CV. The atrial diastolic volumes had decreased significantly at 30 days and ventricular volumes at 180 days. The atrial systolic volumes decreased significantly the day after CV, but the ventricular systolic volumes remained constant the day after CV and decreased thereafter. Only the right atrial volumes were normalized 180 days after CV. The same results were found in a subgroup of patients with lone AF. In conclusion, reversal of atrial dimensions and function happened earlier than ventricular reversal after CV in persistent AF. Atrial reversal began immediately and ventricular reversal was not seen before 30 days after CV. Our results suggest that the changes to the left atrium and both ventricles caused by AF could be permanent and that CV of AF may be preferable.

Amino-terminal pro-B-type natriuretic peptide and B-type natriuretic peptide in the general community: determinants and detection of left ventricular dysfunction

OBJECTIVES

This study sought to characterize factors influencing amino-terminal pro-B-type natriuretic peptide (NT-proBNP) and to evaluate the ability of NT-proBNP to detect left ventricular (LV) dysfunction in a large community sample.

BACKGROUND

Secretion of BNP increases in cardiac disease, making BNP an attractive biomarker. Amino-terminal proBNP, a fragment of the BNP prohormone, is a new biomarker. We evaluated factors influencing NT-proBNP in normal patients and compared the ability of NT-proBNP and BNP to detect LV dysfunction in a large community sample.

METHODS

Amino-terminal pro-BNP was determined in plasma samples of a previously reported and clinically and echocardiographically characterized random sample (n = 1,869, age > or =45 years) of Olmsted County, Minnesota.

RESULTS

In normal patients (n = 746), female gender and older age were the strongest independent predictors of higher NT-proBNP. Test characteristics for detecting an LV ejection fraction < or =40% or < or =50% were determined in the total sample with receiver operating characteristic curves. Amino-terminal pro-BNP had significantly higher areas under the curve for detecting an LV ejection fraction < or =40% or < or =50% than BNP in the total population and in several male and age subgroups, whereas areas were equivalent in female subgroups. Age- and gender-adjusted cutpoints improved test characteristics of NT-proBNP. Both assays detected patients with systolic and/or moderate to severe diastolic dysfunction to a similar degree, which was less robust than the detection of LV systolic dysfunction alone.

CONCLUSIONS

Amino-terminal pro-BNP in normal patients is affected primarily by gender and age, which should be considered when interpreting values. Importantly, in the entire population sample NT-proBNP performed at least equivalently to BNP in detecting LV dysfunction and was superior in some subgroups in detecting LV systolic dysfunction.

Relationship of extent and nature of dysfunctional myocardium to brain natriuretic peptide in patients with ischemic left ventricular dysfunction

We studied the relationship between brain natriuretic peptide (BNP) levels and viable myocardium and ischemic myocardium, regional scar and regional contractile function. Fifty-nine patients underwent dobutamine echocardiography and magnetic resonance imaging and resting BNP levels were determined. By magnetic resonance imaging, total extent of dysfunctional myocardium correlated strongest with BNP (r = 0.60, p < 0.0001). The extent of scar, viability and ischemia also correlated. At dobutamine echocardiography, a composite of dysfunctional and ischemic myocardium was the strongest correlate of BNP (r = 0.48, p < 0.0001), with less strong correlations by global parameters. The extent of dysfunctional myocardium, rather than its nature determines BNP levels.

Angiotensin Receptor Blockade and Exercise Capacity in Adults With Systemic Right Ventricles

Background— Pharmacological blockade of the renin-angiotensin system improves exercise tolerance in patients with left ventricular dysfunction, yet its impact on patients with systemic right ventricles (RVs) remains unknown.

Methods and Results— A multicenter, randomized, double-blind, placebo-controlled, crossover clinical trial was performed to assess the effects of losartan on exercise capacity and neurohormonal levels in patients with systemic RVs. Of 29 patients studied (age, 30.3±10.9 years), 21 had transposition of the great arteries with a Mustard baffle, and 8 had congenitally corrected transposition of the great arteries. Baseline values were as follows: V̇ o 2 max, 29.8±5.6 mL · kg −1 · min −1 (73.5±12.9% predicted value); RV ejection fraction, 41.6±9.3%; N-terminal pro brain natriuretic peptide (NT-proBNP), 257.7±243.4 pg/mL (normal <125 pg/mL); and angiotensin II, 5.7±4.9 pg/mL (normal <5.0 pg/mL). Comparing losartan to placebo showed no differences in V̇ o 2 max (29.9±5.4 versus 29.4±6.2 mL · kg −1 · min −1 ; P =0.43), exercise duration (632.3±123.0 versus 629.9±140.7 seconds; P =0.76), and NT-proBNP levels (201.2±267.8 versus 229.7±291.5 pg/mL; P =0.10), despite a trend toward increased angiotensin II levels (15.2±13.8 versus 8.8±12.5 pg/mL; P =0.08).

Conclusions— In adults with systemic RVs, losartan did not improve exercise capacity or reduce NT-proBNP levels. Minimal baseline activation of the renin-angiotensin system may explain this lack of benefit and imply an alternative pathophysiological mechanism for the progressive ventricular dysfunction and impaired exercise capacity observed in such patients.

Right heart overload contributes to cardiac natriuretic hormone elevation in patients with heart failure

BACKGROUND

Atrial and brain natriuretic peptides (ANP and BNP) plasma concentration increases and holds a prognostic significance in patients with left ventricular dysfunction. We assessed the hypothesis that right ventricular (RV) overload might significantly contribute to plasma elevation of cardiac natriuretic hormones in patients with heart failure.

METHODS

Forty-one patients with cardiomyopathy and depressed left ventricular (LV) function (ejection fraction, EF, <40%), underwent cardiac magnetic resonance imaging (MRI) and resting plasma determination of ANP and BNP. Nineteen healthy subjects were also studied as control group. Ventricular volumes and function were assessed by MRI.

RESULTS

In the group of patients, LVEF was 22.6+/-1.2% (controls: 61.2+/-1.3%, P<0.001, mean+/-S.E.M.), while RVEF was 48.2+/-2.5% (controls: 66.7+/-1.6%, P<0.001); LV and RV end diastolic/systolic volumes, corrected by body surface area, were 143+/-7/114+/-7 ml/m2 (controls 70+/-3/27+/-2 ml/m2, both P<0.001) and 66+/-3/37+/-4 ml/m2 (controls: 63+/-4/21+/-2 ml/m2, P<0.01 only for end-systolic volume). BNP plasma value was on average 324+/-39 pg/ml (range: 23-1280, controls 10+/-2 pg/ml), ANP value was 144+/-17 pg/ml (range: 26-534, controls 15+/-1 pg/ml). BNP positively correlated with either end-diastolic or end-systolic RV volume in patients, less with LV systolic, and not with LV diastolic volume. Moreover, a significant negative correlation was observed between BNP and either LVEF or RVEF. Conversely, ANP showed a significant correlation only with end-systolic RV volume and with both RVEF and LVEF. When multivariate stepwise linear regression analysis was applied LVEF resulted the only independent predictor for ANP plasma values (R=0.591, P<0.001), while LVEF and RV end-diastolic volume for BNP (R=0.881, P<0.001, and R=0.881, P=0.035, respectively).

CONCLUSIONS

Right heart overload contributes independently to plasma elevation of natriuretic peptides. RV involvement, which is known to independently worsen prognosis in patients with cardiomyopathy, might contribute to their established prognostic power, inducing compensatory secretion of plasma cardiac natriuretic hormones.

Prediction of Myocardial Infarction by N-Terminal-Pro-B-Type Natriuretic Peptide, C-Reactive Protein, and Renin in Subjects With Cerebrovascular Disease

Background— B-type natriuretic peptide (BNP), C-reactive protein (CRP), and renin are elevated in persons at risk for cardiovascular disease. However, data that directly compare these markers in the prediction of myocardial infarction (MI) are limited.

Methods and Results— N-terminal-proBNP (NT-proBNP), CRP, and renin were measured in baseline blood samples from a nested case-control study of the 6105 participants of the Perindopril Protection Against Recurrent Stroke Study (PROGRESS), a placebo-controlled study of a perindopril-based blood pressure-lowering regimen among individuals with previous stroke or transient ischemic attack. Each of 206 subjects who experienced MI, either fatal or nonfatal, during a mean follow-up of 3.9 years was matched to 1 to 3 control subjects. Most MI cases (67%) occurred in subjects without a history of coronary heart disease. NT-proBNP, CRP, and renin each predicted MI; the odds ratio for subjects in the highest compared with the lowest quarter was 2.2 (95% CI, 1.3 to 3.6) for NT-proBNP, 2.2 (95% CI, 1.3 to 3.6) for CRP, and 1.7 (95% CI, 1.1 to 2.8) for renin. NT-proBNP and renin, but not CRP, remained predictors of MI after adjustment for all other predictors, including LDL and HDL cholesterol levels. Individuals with both NT-proBNP and renin in their highest quarters had 4.5 times the risk of MI compared with subjects with both biological markers in their lowest quarters.

Conclusions— NT-proBNP and renin, but not CRP, are independent predictors of MI risk after stroke or transient ischemic attack, providing information additional to that provided by classic risk factors, and may enable more effective targeting of MI prevention strategies.

Preoperative plasma N-terminal pro-brain natriuretic peptide as a marker of cardiac risk in patients undergoing elective non-cardiac surgery

Background

Plasma N-terminal pro-brain natriuretic peptide (NTproBNP) is a sensitive marker for heart failure. This study tested whether the preoperative plasma level of NTproBNP could predict cardiac complications in patients undergoing non-cardiac surgery.

Methods

A total of 190 consecutive patients who underwent elective non-cardiac surgery that required general anaesthesia were studied. In addition to routine preoperative evaluation, a blood sample was taken for estimation of plasma NTproBNP concentration. Postoperative cardiac complications were defined as cardiac death, acute coronary syndrome, heart failure and haemodynamic compromise from cardiac arrhythmias.

Results

Fifteen of the 190 patients had a cardiac complication: four had acute coronary syndrome and 13 had congestive heart failure. NTproBNP concentration was significantly higher in patients with a cardiac complication; a level greater than 450 ng/l was predictive of cardiac complications with a sensitivity of 100 per cent and a specificity of 82·9 per cent. Other factors associated with cardiac complications were a higher American Society of Anesthesiologists grade, age and clinical cardiac impairment, but in a multivariate analysis NTproBNP level was the only independent factor.

Conclusion

Preoperative plasma NTproBNP concentration may be an independent predictor of cardiac complications in patients undergoing non-cardiac surgery.

Diagnostic and Prognostic Performance of N-Terminal ProBNP in Primary Care Patients With Suspected Heart Failure

BACKGROUND

The value of N-terminal pro-brain natriuretic peptide (NT-proBNP) in terms of diagnosis and prognosis in congestive heart failure (CHF) and left ventricular systolic dysfunction (LVSD) has been demonstrated previously in various populations, but data on primary care patients are sparse. The aim of this study was to evaluate the diagnostic and prognostic performance of NT-proBNP in primary care patients with suspected CHF.

METHODS AND RESULTS

Three hundred sixty-seven consecutive patients (mean age, 68.8 years; range, 39.0-84.0 years) who had been referred by their general practitioner for echocardiographic evaluation because of suspected CHF. In all patients, NT-proBNP was measured at baseline and left ventricular ejection fraction (LVEF) was estimated with echocardiography. LVSD (LVEF < or =0.40) was found in 9% of the patients. NT-proBNP was significantly higher in patients with LVSD (P < .0001). With predefined cut off values for NT-proBNP (125 pg/mL), the sensitivity, specificity, positive predictive value, and negative predictive value for the detection of LVSD were 0.97, 0.46, 0.15 and 0.99, respectively. Area under the receiver operating characteristic curve was 0.87. The application of an age-differentiated cut-off value for NT-proBNP (125 pg/mL for <75 years old and 450 pg/mL for > or =75 years old) did not increase diagnostic performance. Patients were followed for a median of 778 days; 8% of the patients died during the follow-up period. The mortality rate was higher in patients with NT-proBNP of >125 pg/mL than in patients with normal values (P < .002, log rank), and the difference persisted after controlling for age, gender, and LVEF (hazard ratio per unit increase in log NT-proBNP, 2.2; range, 1.2-4.1; P = .015).

CONCLUSION

In primary care patients who were referred for echocardiography because of suspected CHF, NT-proBNP values <125 pg/mL effectively rule out LVSD. Furthermore low NT-proBNP values are associated with a lower risk of death, independently of age, gender, and LVEF.

Reduced myocardial velocities of left ventricular long-axis contraction identify both systolic and diastolic heart failure-a comparison with brain natriuretic peptide

BACKGROUND

Echocardiographic diagnosis of radial fractional shortening or global ejection fraction fails to diagnose all patients with heart failure; about 40%, with apparently normal global systolic function, will have elevated brain natriuretic peptide (BNP) concentrations and "pure" diastolic dysfunction. Screening methods do not include assessment of left ventricular (LV) longitudinal function, however, which is a more sensitive marker of subclinical disease.

AIMS

We investigated the diagnostic potential of assessment of LV longitudinal function in suspected heart failure, in a comparison against BNP.

METHODS

Fifty consecutive subjects (aged 65+/-12 years; 30 men) referred to a heart failure clinic with unexplained breathlessness were examined by echocardiography and had plasma BNP measured by fluorescence immunoassay.

RESULTS

Global systolic function (ejection fraction) correlated moderately with log-transformed BNP (r=-0.54), as did global diastolic function (r=0.55 for estimated LV filling pressure, and r=-0.51 for transmitral flow propagation velocity), and radial systolic function (r=-0.60) (all p<0.001). The echocardiographic parameter that correlated best with BNP, however, was LV longitudinal systolic function (r=-0.78, p<0.001). By stepwise multiple regression analysis, BNP was predicted by longitudinal systolic velocity, in association with LV mass index and radial systolic velocity (r=0.81, r(2)=0.66, p<0.0001). The sensitivity and specificity of a longitudinal systolic velocity of </=5.5 cm/s (mean of 4 basal segments) to diagnose heart failure (defined as an elevated BNP) were 94% and 85%, respectively; the negative predictive value was 97%.

CONCLUSION

Non-invasive diagnosis or exclusion of suspected heart failure, whether systolic or diastolic, can be performed accurately by echocardiographic measurement of LV longitudinal systolic function.