Natriuretic peptides in patients with atrial fibrillation and advanced chronic heart failure: determinants and prognostic value of (NT-)ANP and (NT-pro)BNP

Relationship of atrial fibrillation and N terminal pro brain natriuretic peptide in heart failure patients

N terminal pro brain natriuretic peptide (NT-proBNP) plays an important role in the diagnosis and prognosis of heart failure (HF). The plasma level of NT-proBNP in atrial fibrillation (AF) patients was higher than of sinus rhythm patients. In HF, NT-proBNP levels are affected by the concomitant presence of AF, making it difficult to distinguish between HF and AF in patients with elevated NT-proBNP. Several other diseases, such as renal failure and pulmonary embolism, are known to further increase NT-proBNP levels in patients with concomitant HF. Therefore, NT-proBNP is a sensitive but non-specific marker for the detection of HF. AF is very important in this regard because among patients with HF regardless of ejection fraction, symptoms such as shortness of breath and atrial enlargement develop and can mimic HF. In the present study, we investigated whether the prognostic value of natriuretic peptides in HF holds true for patients with concomitant AF.

Biomarkers associated with rhythm status after cardioversion in patients with atrial fibrillation

Biomarkers may help to improve our knowledge about the complex pathophysiology of atrial fibrillation (AF). In this study we sought to identify significant changes in biomarkers and clinical measures in patients with and without AF recurrence after electrical cardioversion. We measured 21 conventional and new biomarkers before and 30 days after electrical cardioversion and assessed the associations of changes in biomarker levels with rhythm status at follow-up. Significant between-group changes were observed for bone morphogenetic protein 10 (BMP10), N-terminal pro-B-type natriuretic peptide (NT-proBNP) and total bilirubin. Their respective changes were - 10.4%, - 62.0% and - 25.6% in patients with sinus rhythm, and 3.1%, 1.1% and - 9.4% in patients with recurrent AF, for a between-group difference of - 13.5% (95% confidence interval [CI] - 19.3% to - 7.6%; P < 0.001), - 63.1% (95% CI - 76.6% to - 49.6%; P < 0.001) and - 16.3% (95% CI - 27.9% to - 4.7%; P = 0.007). In multivariable models, the reductions of BMP10 and NT-proBNP were significantly associated with follow-up rhythm status (β coefficient per 1 - SD decrease, - 3.85; 95% CI - 6.34 to - 1.35; P = 0.003 for BMP10 and - 5.84; 95% CI - 10.22 to - 1.47; P = 0.009 for NT-proBNP. In conclusion, changes in BMP10 und NT-proBNP levels were independently associated with rhythm status after cardioversion, suggesting that these markers may be dependent on the actual heart rhythm.

Predictive power of diastolic parameters on medical cardioversion success in acute atrial fibrillation

BACKGROUND

Diastolic function assessment has been reported to provide valuable data in patients with atrial fibrillation (AF). The purpose of this study was to evaluate the effects of diastolic parameters on predicting the effectiveness of medical cardioversion in restoring sinus rhythm among patients with acute AF.

METHODS

40 non-valvular, new onset AF patients were included. All participants received an intravenous infusion of amiodarone. In patients whom sinus rhythm could not be restored with amiodarone, an electrical cardioversion was performed. Two groups, patients who achieved sinus rhythm with amiodarone (Group-1) and who failed to achieve sinus rhythm with amiodarone (Group-2) were compared with respect to initial echocardiographic measurements.

RESULTS

Group-1 patients were younger comparing with Group-2 (mean age; 54.4 ± 13.9 years vs 63.3 ± 10.3 years, p = 0.028). Comparing with Group-1, Group-2 patients had; a higher left atrium volume index (17.1 ± 4.8 cm³ / m² vs 22.6 ± 6.6 cm³ / m² , p = 0.03); a shorter pulmonary vein S (49.6 ± 3.8 cm/sec vs 41.1 ± 3.0 cm/sec, p < 0.001); and a shorter pulmonary vein D peak velocity (55.9 ± 2.4 cm/sec vs 52.3 ± 1.8 cm/sec, p < 0.001). Moreover, both IVRT and DT were significantly shorter in Group-2, comparing with Group-1 (45.1 ± 2.1 msec vs 51.1 ± 2.5 msec, p < 0.001 and 51.3 ± 2.4 msec vs 56.5± 3.2 msec, p < 0.001, respectively).

CONCLUSION

The present study revealed that admission pulmonary vein S and D wave peak velocities, IVRT, DT, and Pro-BNP levels could be predictors of failure of medical cardioversion among AF patients.

Catheter ablation for non-paroxysmal atrial fibrillation accompanied by heart failure with preserved ejection fraction: feasibility and benefits in functions and B-type natriuretic peptide

AIMS

We aimed to examine the benefits of catheter ablation in patients with non-paroxysmal atrial fibrillation (AF) accompanied by heart failure (HF) with preserved ejection fraction (HFpEF), in comparison with the benefits in patients with AF accompanied by HF with reduced ejection fraction (HFrEF) or patients with no HF.

METHODS AND RESULTS

From 1173 consecutive patients undergoing catheter ablation, 502 with non-paroxysmal AF were divided into three groups: no history of HF [plasma B-type natriuretic peptide (BNP) <100 pg/mL and no HF hospitalization; n = 125], HFpEF [left ventricular (LV) EF ≥50%; n = 293], and HF with midrange EF (HFmrEF) + HFrEF (LVEF <50%; n = 84) groups. The endpoints were AF recurrence at 1 year, changes in symptomatic and image-based functional status, and changes in BNP levels from baseline to 1 year. In the HFpEF group, AF recurred in 48 patients (16.4%) and 278 patients (94.8%) had sinus rhythm at 1 year; these values were comparable with those in the other groups. Significant improvement was observed in the left atrial diameter, LVEF, and New York Heart Association functional class in the HFpEF and HFmrEF + HFrEF groups. The BNP level significantly decreased irrespective of the index rate control status, and freedom from AF recurrence was an independent predictor of HF remission, defined as BNP <100 pg/mL at 1 year, in the HFpEF group.

CONCLUSION

Catheter ablation is highly feasible for restoring sinus rhythm in non-paroxysmal AF with coexisting HFpEF, thereby improving cardiac function and BNP levels. Catheter ablation for AF may be an optional management strategy.

Association of natriuretic peptide and adverse outcomes in patients with atrial fibrillation: A meta-analysis

Studies on the association of elevated B-type natriuretic peptide (BNP)/N-terminal pro-B-type natriuretic peptide (NT-proBNP) level with adverse clinical outcomes have yielded conflicting results in patients with atrial fibrillation (AF). This meta-analysis aimed to assess the prognostic value of BNP/NT-proBNP level in AF patients. A comprehensive literature search was conducted using PubMed and Embase databases up to July 1, 2020. Studies investigating the association between BNP/NT-proBNP level and adverse clinical outcomes in patients with AF were eligible. Outcome measures were all-cause mortality, stroke/systemic embolism, major bleed, and major adverse cardiovascular events (MACEs). Ten studies recruiting 29 543 patients with AF were included. Elevated BNP/NT-proBNP level was independently associated with higher risk of all-cause mortality (risk ratios [RR] 1.92; 95% confidence intervals [CI] 1.50-2.45), stroke/systemic embolism (risk ratio [RR] 2.53; 95% CI 2.00-3.19), and MACEs (RR 2.17; 95% CI 1.89-2.49). However, the association between elevated BNP/NT-proBNP level and major bleed was not statistically significant (RR 1.14; 95% CI 0.92-1.40). Elevated BNP/NT-proBNP level is significantly associated with higher risk of all-cause mortality, stroke/systemic embolism, and MACEs. Determination of BNP/NT-proBNP level may play an important role in risk stratification of AF patients.

Association between body mass index and mortality in atrial fibrillation patients with and without diabetes mellitus: Insights from a multicenter registry study in China

BACKGROUND AND AIMS

The aim of this study was to evaluate the association between body mass index (BMI) and mortality in atrial fibrillation (AF) patients with and without diabetes mellitus (DM).

METHODS AND RESULTS

A total of 1991 AF patients were enrolled and divided into two groups according to whether they have DM at recruitment. Baseline information was collected and a mean follow-up of 1 year was carried out. The primary outcome was defined as all-cause mortality with the secondary outcomes including cardiovascular mortality, stroke and major adverse events (MAEs). Univariable and multivariable Cox regression were performed to estimate the association between BMI and 1-year outcomes in AF patients with and without DM. 309 patients with AF (15.5%) had comorbid DM at baseline. Patients with DM were more likely to have cardiovascular comorbidities, receive relevant medications but carry worse 1-year outcomes. Multivariable Cox regressions indicated that elevated BMI was related with reduced risk of all-cause mortality, cardiovascular mortality and major adverse events. Compared to normal weight, overweight [HR (95% CI): 0.548 (0.405-0.741), p < 0.001] and obesity [HR (95% CI): 0.541 (0.326-0.898), p = 0.018] were significantly related with decreased all-cause mortality for the entire cohort. Remarkably reduced all-cause mortality in the overweight [HR (95% CI): 0.497 (0.347-0.711), p < 0.001] and obesity groups [HR (95% CI): 0.405 (0.205-0.800), p = 0.009] could also be detected in AF patients without DM, but not in those with DM.

CONCLUSION

Elevated BMI was associated with reduced mortality in patients with AF. This association was modified by DM. The obesity paradox confined to AF patients without DM, but could not be generalized to those with DM.

Gender-specific association between body mass index and all-cause mortality in patients with atrial fibrillation

Background

Elevated body mass index (BMI) is related with reduced mortality in various cardiovascular diseases.

Hypothesis

Gender‐specific association between BMI and mortality exists in atrial fibrillation (AF).

Methods

In this multicenter observational study with a mean follow‐up of 1 year, a total of 1991 AF patients were enrolled and divided into two groups based on the gender. The primary endpoint was all‐cause mortality while the secondary endpoints were defined as cardiovascular mortality, stroke, and major adverse events during 1‐year follow‐up. Cox regression was performed to identify the association between BMI and clinical outcomes according to gender.

Results

Female patients with AF tended to be older (P = .027) and thinner (P < .001) than male patients with AF. They were more likely to have heart failure, hyperthyroidism, and valvular AF (all P < .05), but less likely to have coronary artery disease and prior myocardial infarction (all P < .01). Multivariate analysis revealed that overweight (HR(95%CI): 0.55(0.41‐0.75), P < .001) and obese patients (HR(95%CI): 0.56(0.34‐0.94), P = .028) were associated with significant lower all‐cause mortality compared with normal weight patients for the entire cohort. Similar association between elevated BMI and reduced all‐cause mortality were only identified in female patients with AF (overweight vs normal weight: HR(95%CI): 0.43(0.27‐0.70); obesity vs normal weight: HR(95%CI): 0.46(0.22‐0.97)), but not in male patients with AF.

Conclusion

This study indicates that overweight and obesity were related with improved survival in patients with AF. The association between elevated BMI and reduced mortality was dependent on gender, which was only significant in female patients, rather than male patients.

N-terminal pro brain natriuretic peptide eliminates the prognostic effect of atrial fibrillation in patients with chronic heart failure

AIMS

Co-morbid atrial fibrillation (AF) increases both mortality and N-terminal pro brain natriuretic peptide (NT-proBNP) concentrations in patients with chronic heart failure (CHF). It is unclear whether AF worsens prognosis independently from NT-proBNP concentrations. If AF was an independent risk factor, NT-proBNP levels for outcome prediction would need to be adjusted in patients with AF. We aimed to analyse the influence of AF on the prognostic value of NT-proBNP in patients with CHF.

METHODS AND RESULTS

A total of 2541 consecutive CHF patients with sinus rhythm (SR) or AF were identified in the outpatients' CHF registry of the University of Heidelberg, Germany. Of these, 250 patients with SR were individually matched to 250 patients with AF with respect to NT-proBNP, New York Heart Association functional class, sex, age, and aetiology of CHF. In the general sample, both AF and NT-proBNP were associated with all-cause mortality [hazard ratio (HR) = 1.96, 95% confidence interval (CI) 1.61-2.39, P < 0.001; and HR = 1.03 per 1000 ng/L increase, 95% CI 1.02 to 1.04, P < 0.001, respectively]. After matching, NT-proBNP retained its prognostic power (HR = 1.13 per 1000 ng/L increase, 95% CI 1.10 to 1.16, P < 0.001), but AF did not (HR = 0.91, 95% CI 0.66 to 1.25, P = 0.56). Despite similar prognosis, matched patients with SR were in more advanced CHF than were AF patients as indicated by a lower left ventricular ejection fraction (30 ± 13% vs. 34 ± 14%, P < 0.001).

CONCLUSIONS

The prognostic value of NT-proBNP in CHF is not influenced by concomitant AF. AF, in return, might be a surrogate of a worse cardiac condition rather than an independent risk factor.

The influence of atrial fibrillation on the levels of NT-proBNP versus GDF-15 in patients with heart failure

Background

In heart failure (HF), levels of NT-proBNP are influenced by the presence of concomitant atrial fibrillation (AF), making it difficult to distinguish between HF versus AF in patients with raised NT-proBNP. It is unknown whether levels of GDF-15 are also influenced by AF in patients with HF. In this study we compared the plasma levels of NT-proBNP versus GDF-15 in patients with HF in AF versus sinus rhythm (SR).

Methods

In a post hoc analysis of the index cohort of BIOSTAT-CHF (n = 2516), we studied patients with HF categorized into three groups: (1) AF at baseline (n = 733), (2) SR at baseline with a history of AF (n = 183), and (3) SR at baseline and no history of AF (n = 1025). The findings were validated in the validation cohort of BIOSTAT-CHF (n = 1738).

Results

Plasma NT-proBNP levels of patients who had AF at baseline were higher than those of patients in SR (both with and without a history of AF), even after multivariable adjustment (3417 [25th–75th percentile 1897–6486] versus 1788 [682–3870], adjusted p < 0.001, versus 2231 pg/mL [902–5270], adjusted p < 0.001). In contrast, after adjusting for clinical confounders, the levels of GDF-15 were comparable between the three groups (3179 [2062–5253] versus 2545 [1686–4337], adjusted p = 0.36, versus 2294 [1471–3855] pg/mL, adjusted p = 0.08). Similar patterns of both NT-proBNP and GDF-15 were found in the validation cohort.

Conclusion

These data show that in patients with HF, NT-proBNP is significantly influenced by underlying AF at time of measurement and not by previous episodes of AF, whereas the levels of GDF-15 are not influenced by the presence of AF. Therefore, GDF-15 might have additive value combined with NT-proBNP in the assessment of patients with HF and concomitant AF.

Graphic abstract

Electronic supplementary material

The online version of this article (10.1007/s00392-019-01513-y) contains supplementary material, which is available to authorized users.

Prognostic Value of N-Terminal Pro-B-Type Natriuretic Peptide Levels in Heart Failure Patients With and Without Atrial Fibrillation

BACKGROUND

Patients with heart failure (HF) and atrial fibrillation (AF) have higher circulating levels of NT-proBNP (N-terminal pro-B-type natriuretic peptide) than HF patients without AF. There is uncertainty about the prognostic importance of a given concentration of NT-proBNP in HF patients with and without AF. We investigated this question in a large cohort of patients with HF and reduced ejection fraction.

METHODS AND RESULTS

We studied 14 737 patients with HF and reduced ejection fraction and a measurement of NT-proBNP at time of screening, enrolled in either the PARADIGM-HF trial (Prospective Comparison of ARNI With ACEI to Determine Impact on Global Mortality and Morbidity in Heart Failure) or the ATMOSPHERE trial (Aliskiren Trial to Minimize Outcomes in Patients With Heart Failure), of whom 3575 (24%) had AF on their baseline ECG. Median (Q1, Q3) levels of NT-proBNP were 1817 pg/mL (1095-3266 pg/mL) in those with AF and 1271 pg/mL (703-2569 pg/mL) in those without (P<0.0001). Patients with AF were older (67 versus 62 years), had worse New York Heart Association class (III/IV; 36% versus 24%), and experienced fewer previous HF hospitalizations (52% versus 61%) or myocardial infarction (30% versus 46%); all P<0.001. We categorized patients with and without AF into 5 NT-proBNP bands: <400, 400 to 999 (reference), 1000 to 1999, 2000 to 2999, and ≥3000 pg/mL. For the primary composite outcome of cardiovascular death or HF hospitalization, event rates differed for patients with and without AF in the lowest band (<400 pg/mL; 8.2 versus 5.0 per 100 patient-years), but not for the higher bands (400-999 pg/mL, 7.4 versus 7.7 per 100 patient-years; 1000-1999 pg/mL, 9.8 versus 11.4 per 100 patient-year; 2000-2999 pg/mL, 13.5 versus 13.4 per 100 patient-years; ≥3000 pg/mL, 22.7 versus 23.0 per 100 patient-years). These findings were consistent whether NT-proBNP was examined as a categorical or continuous variable and before and after adjustment for other prognostic variables. We found similar results for the components of the composite outcome and all-cause mortality.

CONCLUSIONS

HF and reduced ejection fraction patients with AF had higher NT-proBNP than those without AF. However, above a concentration of 400 pg/mL (representing most patients in each group), NT-proBNP had similar predictive value for adverse cardiovascular outcomes, irrespective of AF status.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier NCT00853658 (ATMOSPHERE) and NCT01035255 (PARADIGM-HF).

Comparative accuracy of NT-proBNP and MR-proANP for the diagnosis of acute heart failure in dyspnoeic patients

AIMS

To compare the performance of the natriuretic peptides (NPs) NT-proBNP and MR-proANP for the diagnosis of acute heart failure (AHF) in subsets of conditions potentially confounding the interpretation of NPs.

METHODS AND RESULTS

We studied 312 patients, presenting to the emergency department with new onset of dyspnoea or worsening of chronic dyspnoea within the last 2 weeks. Performance of NPs for the diagnosis of AHF was tested and compared using C-statistics in the entire cohort and in conditions previously described to confound interpretation of NPs such as older age, renal failure, obesity, atrial fibrillation or paced rhythm, and in the NT-proBNP grey zone. AHF was diagnosed in 139 patients. In the entire cohort, the diagnostic performance of NT-proBNP was comparable with that of MR-proANP. Receiver operating characteristic analysis demonstrated that optimal diagnostic cut-offs were higher in the presence of older age, kidney failure or rhythm disorder. However, there were no statistically relevant differences between the receiver operating characteristic curves analysed in the total population and those studied in the pre-specified subsets severe kidney failure, advanced age, obesity, atrial fibrillation and paced rhythm, and grey zone NT-proBNP values. Moreover, the diagnostic performance of NT-proBNP was comparable with that of MR-proANP in the subsets.

CONCLUSIONS

The performance of NT-proBNP and MR-proANP for AHF is comparable in the total population as well as in the subsets with potentially confounding characteristics such as older age, renal dysfunction, obesity, atrial fibrillation and paced rhythm, or those with NT-proBNP values in the grey zone.

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

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

CHA2DS2-VASc score and blood biomarkers to identify patients with atrial high-rate episodes and paroxysmal atrial fibrillation

AIMS

Paroxysmal atrial fibrillation (PAF) is often asymptomatic but nonetheless harmful. We evaluated the performance of disease-related blood biomarkers and CHA2DS2-VASc score to discriminate for PAF in patients with continuous rhythm monitoring.

METHODS AND RESULTS

Clinical data and blood samples were obtained from patients with dual-chamber pacemakers selected according to the absence (no_AHRE) or presence of Atrial High-Rate Episodes (AHRE) >6 min in recent device history (case-control approach). We included 93 patients (n = 49 AHRE, n = 44 no_AHRE). In a subgroup with high AHRE burden and confirmed PAF 15 biomarkers were evaluated (n = 19 AHRE-AF vs. n = 20 no_AHRE). Significantly regulated biomarkers were then tested in all patients to distinguish no_AHRE from AHRE (receiver operating characteristics analysis). Hsp27, TGFβ1, cystatin C, matrix metalloproteinases MMP-2,-3,-9, albumin, and serum uric acid were not altered in the subgroup. Tissue inhibitors of metalloproteinases (TIMP) -1,-2,-4; NT-proANP, NT-proBNP, IL-6 and serum amyloid protein A were significantly different in AHRE vs. no_AHRE (subgroup and whole cohort), with best discriminatory performance for TIMP-4. Biomarkers performed better than CHADS2-VASc for AHRE discrimination. Intracardial electrograms and medical history from seven AHRE patients suggested atrial tachycardia and not AF (AHRE-AT). Four of the most relevant regulated biomarkers (TIMP-4, TIMP-2, SAA, NT-proBNP) behaved similarly in AHRE-AT and AHRE-AF. NT-proBNP >150 pg/mL indicated an odds ratio of 12.9 for AHRE. Combining two biomarkers significantly improved discrimination of AHRE.

CONCLUSION

TIMP-4, NT-proANP, NT-proBNP were strongest associated with PAF and AHRE. The discriminatory performance of CHADS2-VASc for PAF was increased by addition of selected biomarkers.

Natriuretic Peptides as Cardiovascular Safety Biomarkers in Rats: Comparison With Blood Pressure, Heart Rate, and Heart Weight

Cardiovascular (CV) toxicity is an important cause of failure during drug development. Blood-based biomarkers can be used to detect CV toxicity during preclinical development and prioritize compounds at lower risk of causing such toxicities. Evidence of myocardial degeneration can be detected by measuring concentrations of biomarkers such as cardiac troponin I and creatine kinase in blood; however, detection of functional changes in the CV system, such as blood pressure, generally requires studies in animals with surgically implanted pressure transducers. This is a significant limitation because sustained changes in blood pressure are often accompanied by changes in heart rate and together can lead to cardiac hypertrophy and myocardial degeneration in animals, and major adverse cardiovascular events (MACE) in humans. Increased concentrations of NPs in blood correlate with higher risk of cardiac mortality, all-cause mortality, and MACE in humans. Their utility as biomarkers of CV function and toxicity in rodents was investigated by exploring the relationships between plasma concentrations of NTproANP and NTproBNP, blood pressure, heart rate, and heart weight in Sprague Dawley rats administered compounds that caused hypotension or hypertension, including nifedipine, fluprostenol, minoxidil, L-NAME, L-thyroxine, or sunitinib for 1-2 weeks. Changes in NTproANP and/or NTproBNP concentrations were inversely correlated with changes in blood pressure. NTproANP and NTproBNP concentrations were inconsistently correlated with relative heart weights. In addition, increased heart rate was associated with increased heart weights. These studies support the use of natriuretic peptides and heart rate to detect changes in blood pressure and cardiac hypertrophy in short-duration rat studies.

Review Of Obesity And Atrial Fibrillation: Exploring The Paradox

There is a well established association between obesity and atrial fibrillation (AF). Nevertheless, the effects of obesity in the outcomes of patients with AF has not been investigated since a few years before. In this regard, several studies have demonstrated a better clinical prognosis of AF in overweight and obese populations. In the present manuscrit, we aimed to explore the main articles in which the "obesity paradox in AF" was found.

Atrial fibrillation impairs the diagnostic performance of cardiac natriuretic peptides in dyspneic patients: results from the BACH Study (Biomarkers in ACute Heart Failure)

OBJECTIVES

The purpose of this study was to assess the impact of atrial fibrillation (AF) on the performance of mid-region amino terminal pro-atrial natriuretic peptide (MR-proANP) in comparison with the B-type peptides (BNP and NT-proBNP) for diagnosis of acute heart failure (HF) in dyspneic patients.

BACKGROUND

The effects of AF on the diagnostic and prognostic performance of MR-proANP in comparison with the B type natriuretic peptides have not been previously reported.

METHODS

A total of 1,445 patients attending the emergency department with acute dyspnea had measurements taken of MR-proANP, BNP, and NT-proBNP values on enrollment to the BACH trial and were grouped according to presence or absence of AF and HF.

RESULTS

AF was present in 242 patients. Plasma concentrations of all three peptides were lowest in those with neither AF nor HF and AF without HF was associated with markedly increased levels (p < 0.00001). HF with or without AF was associated with a significant further increment (p < 0.00001 for all three markers). Areas under receiver operator characteristic curves (AUCs) for discrimination of acute HF were similar and powerful for all peptides without AF (0.893 to 0.912; all p < 0.001) with substantial and similar reductions (0.701 to 0.757) in the presence of AF. All 3 peptides were independently prognostic but there was no interaction between any peptide and AF for prediction of all-cause mortality.

CONCLUSIONS

AF is associated with increased plasma natriuretic peptide (MR-proANP, BNP and NT-proBNP) levels in the absence of HF. The diagnostic performance of all three peptides is impaired by AF. This warrants consideration of adjusted peptide thresholds for diagnostic use in AF and mandates the continued search for markers free of confounding by AF.

Simultaneous predictive value of NT-proBNP and CA-125 in patients newly diagnosed with advanced heart failure: preliminary results

INTRODUCTION

New markers of cardiac events and new monitoring methods which can improve care of patients with advanced heart failure (HF) are still being looked for.

MATERIAL AND METHODS

Sixty-five patients below 75 years old (mean age: 60.34 ±9.54 years), hospitalized with the first manifestation of HF (left ventricular ejection fraction ≤ 40%) and New York Heart Association (NYHA) class II-IV symptoms, not optimally treated before the study, were included. Blood samples for NT-proBNP and CA-125 were taken at baseline and during the 12-month follow-up period. The doses of β-adrenolytics and angiotensin-converting enzyme (ACE) inhibitors were titrated to maximal tolerated ones according to the guidelines in 1-year follow-up. The endpoint was established as overall death and time to death.

RESULTS

WORSE PROGNOSIS WAS OBSERVED IN GROUPS WITH: 1) NT-proBNP and CA-125 above medians (OR = 492.9, p = 0.006), 2) baseline higher NT-proBNP and CA-125 (HR = 0.016, p < 0.001), 3) increased or stable marker levels during the first 3 months after treatment implementation.

CONCLUSIONS

Elevated values of NT-proBNP and CA-125 are found as the independent death risk factors. The group with initial elevated NT-proBNP and CA-125 concentrations had a worse prognosis. Changes in NT-proBNP and CA-125 levels after treatment implementation predict unfavourable cardiovascular events with better CA-125 than NT-proBNP performance.

Cardiac gene expression profiling - the quest for an atrium-specific biomarker

Biomarkers are gaining increasing interest to predict risk but also to aid in diagnostics. Tissue-specific biomarkers are of utmost importance to detect diseases of respective organs. As of yet there are no atrium-specific biomarkers for risk stratification of atrial disease, such as atrial fibrillation. Bioinformatics such as mRNA microarrays can help to detect tissue-enriched and possibly tissue-specific expressed genes that can be targets for biomarkers. We describe an approach to identify genes preferably expressed in atrial cardiomyocytes compared with ventricular cardiomyocytes by RNA microarray and confirmed by quantitative real-time polymerase chain reaction. By this approach we identified several atrium-enriched genes but also ventricle-enriched genes. As expected atrial natriuretic peptide (ANP) mRNA showed higher expression in atrial cardiomyocytes while with adrenergic stimulation expression was almost as high in ventricular as in atrial cells. Brain-type natriuretic peptide (BNP), however, was not different between atrial and ventricular cells giving a possible explanation for increased levels of NT-proBNP in atrial fibrillation patients. Interesting identified candidates are serpine1 and ltbp2 as atrium-enriched genes whereas alpha-adrenergic receptor subtype 1b and S100A1 expression was significantly higher in ventricular cells. The identified genes need to be confirmed in human tissue and might ultimately be tested as potential biomarkers for atrial stress. (Neth Heart J 2010;18:610-4.).

N-terminal pro-b-type natriuretic peptide and left atrial function in patients with congestive heart failure and severely reduced ejection fraction

AIMS

Amino-terminal portion of pro-B-type natriuretic peptide (NT-pro-BNP) is a valuable diagnostic and prognostic marker in congestive heart failure (CHF). In CHF patients, elevation of natriuretic peptide levels correlate with decreased left ventricular (LV) ejection fraction (EF) and increased left atrial (LA) volumes, but a correlation with LA function that is a determinant of haemodynamic and clinical status in CHF with independent prognostic value has never been investigated. Aim of this study was to evaluate the relationship between cardiac neurohormonal activation and LA function in patients with CHF due to dilated cardiomyopathy.

METHODS AND RESULTS

One hundred and one patients (86% males; mean age, 64 ± 11 years) with dilated ischaemic or non-ischaemic cardiomyopathy, LV EF ≤45% (mean LV EF, 33 ± 8%), and New York Heart Association class II-IV underwent transthoracic echocardiography to evaluate LA fractional active and total emptying from M- and B-Mode images, and, on the same day, venous blood sample collection to dose NT-pro-BNP. By univariate analyses, NT-pro-BNP significantly correlated to age, LA dimensions, LA function indexes, EF, and functional class. At multivariate analysis, LV EF and M- or B-Mode indexes of LA function were the only independent predictors of NT-pro-BNP values. A NT-pro-BNP cut-off of 1480 pg/mL identified LA dysfunction with 89% specificity and 54% sensitivity.

CONCLUSION

In CHF patients with severely impaired systolic function, NT-pro-BNP levels reflect LA and LV dysfunction. These data should prompt studies to investigate the relationship between changes of LA function and NT-pro-BNP levels and their clinical value as prognostic and therapeutic targets in CHF.

Profiling B-type natriuretic peptide in a stable heart failure population: a valuable adjunct to care

AIM

To examine the prognostic importance of absolute values and change in values of BNP in patients with stable heart failure (HF).

METHODS

Five-hundred and fifty-nine patients attending a disease management programme were categorized into tertiles of BNP (group 1; ≤ 95 pg/ml, group 2; 96-249 pg/ml and group 3; ≥ 250 pg/ml). A change in BNP between two stable visits was recorded. Patients were followed up for 1 year for death and a composite morbidity measure of HF hospitalization, all-cause hospitalization, unscheduled visits for clinical deterioration(UC) of HF using survival analysis.

RESULTS

The risk of the combined morbidity outcome increased with increasing tertiles of BNP (Log rank = 17.8 (2), p < 0.001). Furthermore, a 50 and 25% increase in BNP predicted morbidity in stable HF patients with an initial BNP > 200 pg/ml (p = 0.02) and > 450 pg/ml (p = 0.03), respectively.

CONCLUSION

In a stable community HF population, an elevated BNP or an increase in BNP predicts an adverse prognosis thereby potentially identifying a population in need of closer clinical follow-up.

Influence of obesity on outcomes in atrial fibrillation: yet another obesity paradox

BACKGROUND

Obese patients have favorable outcomes in congestive heart failure, hypertension, peripheral vascular disease, and coronary artery disease. Obesity also has been linked with increased incidence of atrial fibrillation, but its influence on outcomes in atrial fibrillation patients has not been investigated. The objective of this research is to investigate the effect of obesity on outcomes in atrial fibrillation.

METHODS

The Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) study was one of the largest multicenter trials of atrial fibrillation, with 4060 patients. Subjects were randomized to rate versus rhythm-control strategy. We performed a post hoc analysis of the National Heart, Lung and Blood Institute limited access dataset of atrial fibrillation patients who had body mass index (BMI) data available in the AFFIRM study. BMI data were not available on 1542 patients. Patients with BMI >or=18.5 were split into normal (18.5-25), overweight (25-30), and obese (>30) categories as per BMI (kg/m(2)). Multivariate Cox proportional hazards regression was used on the eligible 2492 patients. End points were all-cause mortality and cardiovascular mortality.

RESULTS

Over three fourths of all patients in our cohort were overweight or obese. There were 304 deaths (103 among normal weight, 108 among overweight, and 93 among obese) and 148 cardiovascular deaths (54 among normal weight, 41 among overweight, and 53 among obese) over a mean period of 3 years of patient follow-up. On multivariate analysis, overweight (hazard ratio [HR] 0.64; 95% confidence interval [CI], 0.48-0.84; P=.001) and obese (HR 0.80; 95% CI, 0.68-0.93; P=.005) categories were associated with lower all-cause mortality as compared with normal weight. Overweight (HR 0.40; 95% CI, 0.26-0.60; P <.001) and obese patients (HR 0.77; 95% CI, 0.62-0.95; P=.01) also had lower cardiovascular mortality as compared with the normal weight patients.

CONCLUSIONS

Although in prior studies, obesity has been associated with increased risk of atrial fibrillation, an obesity paradox exists for outcomes in atrial fibrillation. Obese patients with atrial fibrillation appear to have better long-term outcomes than nonobese patients.

Neurohormonal profile of patients with heart failure and diabetes

Background. Neurohormonal activation is generally recognised to play an important role in the pathophysiology, prognosis and treatment of chronic heart failure (HF). While the number of patients with diabetes increases, little if anything is known about neurohormonal activation in HF patients with diabetes. Methods. The study population consisted of 371 patients with advanced HF who were enrolled in a multicentre survival trial. Ten different plasma neurohormones were measured (noradrenaline, adrenaline, dopamine, aldosterone, renin, endothelin, atrial natriuretic peptide [ANP], N-terminal (pro)ANP, brain natriuretic peptide [BNP] and N-terminal (pro)BNP. Comparisons were made between patients with diabetes (n=81) and those without (n=290). Results. At baseline, the two groups were comparable regarding age (mean 68 years), left ventricular ejection fraction (23%), severity and aetiology of HF, while body weight was higher in those with diabetes (77.4 vs. 74.2 kg, p=0.04). Most plasma neurohormones were similar between groups, but patients with diabetes had higher values of BNP (94 vs. 47 pmol/l, p=0.03), while a similar trend was observed for N-terminal (pro)BNP (750 vs. 554 pmol/l, p=0.10). During almost five years of follow-up, 51/81 patients with diabetes died (63%), as compared with 144 of 290 non-diabetic patients (50%) who died (p=0.046). Natriuretic peptides and noradrenaline were the most powerful predictors of mortality in both diabetic and non-diabetic HF patients. Conclusion. HF patients with diabetes have higher (N-terminal (pro)) BNP levels than non-diabetic patients, while other neurohormones are generally similar. Natriuretic peptides are also good prognostic markers in diabetic HF patients. (Neth Heart J 2010;18:190-6.).

Atrial fibrillation and amino-terminal pro-brain natriuretic peptide as independent predictors of prognosis in systolic heart failure

BACKGROUND

Survival of patients with systolic heart failure (HF) may be influenced by the presence of chronic atrial fibrillation (AF) and circulating concentrations of B-type natriuretic peptides. In this study, we sought to assess the prognostic value of chronic AF in comparison to those of amino-terminal pro-brain natriuretic peptide (NT-proBNP) plasma levels and of echocardiographic parameters among HF patients of the entire study population and in those with AF.

METHODS

Plasma NT-proBNP levels and echocardiography were prospectively assessed in 489 patients with chronic systolic HF (LV ejection fraction <or=45%) in sinus rhythm or AF (16%). Follow-up duration was 26+/-15 months.

RESULTS

Patients with AF were older (p<0.0001), had a worse NYHA class (p=0.002) and higher NT-proBNP levels (p<0.0001) than those in sinus rhythm. Presence of AF (HR [hazards ratio]: 2.01, p=0.013) and plasma NT-proBNP (HR: 3.05, p<0.0001) were the only independent predictors of all-cause mortality. At receiver operating characteristic analyses, the threshold level for outcome prediction of NT-proBNP was higher in patients with AF (3883 pg/ml) than in patients in sinus rhythm (1653 pg/ml). Multivariate analysis performed in patients with HF and AF showed that plasma NT-proBNP was the most important predictor of death after statistic adjustment for age.

CONCLUSIONS

Chronic AF and NT-proBNP independently predicted the outcome of patients with HF. The threshold level of NT-proBNP for outcome prediction was different in patients with AF with respect to those in sinus rhythm. NT-proBNP was the most important independent predictor of all-cause mortality in HF patients with AF.

Amino-terminal pro-B-type natriuretic peptide testing for the diagnosis or exclusion of heart failure in patients with acute symptoms

When used for the evaluation of patients with acute symptoms in the emergency department setting, amino-terminal pro-B-type natriuretic peptide (NT-proBNP) testing is highly sensitive and specific for the diagnosis or exclusion of acute destabilized heart failure (HF), with results comparable to those reported for B-type natriuretic peptide (BNP) testing. When used for the diagnostic evaluation of the patient with possible HF, NT-proBNP testing returns information that may be superior to clinical judgment. However, the optimal application of NT-proBNP is in concert with history and physical examination, adjunctive testing, and with the knowledge of the differential diagnosis of an elevated NT-proBNP level. Studies indicate a dual use for NT-proBNP, both to exclude acute HF (where NT-proBNP concentrations <300 ng/L have a 98% negative predictive value), as well as to identify the diagnosis. To identify acute HF in patients with dyspnea, an age-independent NT-proBNP cut point of 900 ng/L has a similar value as that reported for a BNP value of 100 ng/L. However, age stratification of NT-proBNP using cut points of 450, 900, and 1,800 ng/L (for age groups of <50, 50-75, and >75 years) reduces false-negative findings in younger patients, reduces false-positive findings in older patients, and improves the overall positive predictive value of the marker without a change in overall sensitivity or specificity. Clinically validated, cost-effective algorithms for the use of NT-proBNP testing exist. Therefore, the logical use of NT-proBNP for the evaluation of the patient with suspected acute HF is useful, cost-effective, and may reduce adverse outcomes compared with standard clinical evaluation without natriuretic peptide testing.

Amino-terminal pro-B-type natriuretic peptides and prognosis in chronic heart failure

In patients with chronic heart failure (HF), amino-terminal pro-B-type natriuretic peptide (NT-proBNP) levels are among the strongest independent predictors of hazard, and their measurement is useful for prognostication across the entire spectrum of HF disease severity. In patients with chronic HF, repeated determinations of NT-proBNP levels appear to convey additional prognostic value for relevant adverse outcomes, including death or HF hospitalization. Although "hard targets" for NT-proBNP values are not entirely defined, morbidity and mortality in chronic HF appear to increase markedly with an NT-proBNP concentration >1,000 ng/L. Confounding factors (such as renal function or obesity) should be kept in mind when prognostically evaluating patients using NT-proBNP measurements; however, the value of NT-proBNP is retained in these patients. Thus, serial assessment of NT-proBNP is valuable for prognostication in chronic HF in outpatients, and, as such, a measurement at each patient visit or the following of changes in clinical stability is recommended.

The differential diagnosis of an elevated amino-terminal pro-B-type natriuretic peptide level

Although amino-terminal pro-B-type natriuretic peptides (NT-proBNP) are useful for the diagnosis or exclusion of heart failure (HF), this marker may identify a wide range of disease processes other than HF. Indeed, elevation of NT-proBNP may occur in a number of heart diseases (including heart muscle disease, valve disease, rhythm abnormalities, pulmonary hypertension, and cytotoxic injury to the heart) and in disease processes other than primary cardiac illnesses, including gram-negative sepsis. Importantly, although NT-proBNP may increase in settings other than HF, the presence and severity of such NT-proBNP release is often significantly associated with risk for adverse outcome. Accordingly, elevation of NT-proBNP in the context of non-HF situations should not be regarded as a "false-positive" finding, and elevated NT-proBNP values should not be discarded without consideration of the serious adverse outcomes associated with the elevation. Future studies will be necessary to further understand the utility of NT-proBNP testing in states other than cardiovascular disease.

Natriuretic peptides

Natriuretic peptides (NPs) are released from the heart in response to pressure and volume overload. B-type natriuretic peptide (BNP) and N-terminal-proBNP have become important diagnostic tools for assessing patients who present acutely with dyspnea. The NP level reflects a compilation of systolic and diastolic function as well as right ventricular and valvular function. Studies suggest that using NPs in the emergency department can reduce the consumption of hospital resources and can lower costs by either eliminating the need for other, more expensive tests or by establishing an alternative diagnosis that does not require hospital stay. Caveats such as body mass index and renal function must be taken into account when analyzing NP levels. Natriuretic peptide levels have important prognostic value in multiple clinical settings, including in patients with stable coronary artery disease and with acute coronary syndromes. In patients with decompensated heart failure due to volume overload, a treatment-induced drop in wedge pressure is often accompanied by a rapid drop in NP levels. Knowing a patient's NP levels might thus assist with hemodynamic assessment and subsequent treatment titration. Monitoring NP levels in the outpatient setting might also improve patient care and outcomes.

N-terminal pro B-type natriuretic peptide levels predict newly detected atrial fibrillation in a population-based cohort

BACKGROUND

B-type natriuretic peptide (BNP) is secreted from cardiomyocytes and may reflect haemodynamic abnormalities predisposing to atrial fibrillation (AF). We aimed to investigate whether N-terminal pro BNP (NT-proBNP) is associated with newly detected AF in subjects obtained from the general population.

METHODS

From the PREVEND programme (n=8592), we selected all subjects with an available baseline and four-year electrocardiogram and NTproBNP levels at baseline. We excluded subjects with AF at baseline and subjects with a serum creatinine >2.0 mg/dl.

RESULTS

In total, 6494 subjects were eligible for the prospective analysis (aged 49+/-12 years, 49.7% men). At four years, AF was detected in 41 (0.6%) subjects. Median NT-proBNP levels at baseline in subjects with newly detected AF after four years was 62.2 (22.6 to 208.5) pg/ml as compared with 35.7 (15.9 to 68.7) pg/ml in those with sinus rhythm (p=0.001). Each 1 standard deviation increment in natural log transformed NT-proBNP was associated with a 54% (5% to 126%, p=0.028) increase in risk for AF after adjustment for other risk factors predisposing to AF. NT-proBNP levels above the sex-specific 80th percentile (97 pg/ml in women and 60 pg/ml in men) were associated with a multivariate odds ratio of 2.65 (1.22 to 5.76, p=0.01) for the occurrence of AF.

CONCLUSION

Plasma levels of NT-proBNP predict newly detected AF in subjects obtained from the general population independent of cardiovascular risk factors predisposing to AF. (Neth Heart J 2008;16:73-8.).

Recent advances in natriuretic peptide research

The natriuretic peptides are a family of related hormones that play a crucial role in cardiovascular and renal homeostasis. They have recently emerged as potentially important clinical biomarkers in heart failure. Natriuretic peptides, particularly brain natriuretic peptide (BNP) and the inactive N-terminal fragment of BNP, NT-proBNP, that has an even greater half-life than BNP, are elevated in heart failure and therefore considered to be excellent predictors of disease outcome. Nesiritide, a recombinant human BNP, has been shown to provide symptomatic and haemodynamic improvement in acute decompensated heart failure, although recent reports have suggested an increased short-term risk of death with nesiritide use. This review article describes: the current use of BNP and its inactive precursor NT-proBNP in diagnosis, screening, prognosis and monitoring of therapy for congestive heart failure, the renoprotective actions of natriuretic peptides after renal failure and the controversy around the therapeutic use of the recombinant human BNP nesiritide.

Left atrial remodelling contributes to the progression of asymptomatic left ventricular systolic dysfunction to chronic symptomatic heart failure

Systolic heart failure (HF) is a progressive disorder that often begins with asymptomatic left ventricular (LV) systolic dysfunction and culminates in symptoms from fluid overload and poor end-organ perfusion. The progression to symptomatic HF is accompanied by marked activation of neurohormonal and cytokine systems, as well as a series of adaptive LV anatomical and functional changes, collectively referred to as LV remodelling. However, the mechanisms underlying symptom appearance have not been delineated and the weight of experimental and clinical evidence suggests that the development of symptomatic HF occurs independently of the haemodynamic status of the patient. The left atrium is a muscular chamber strategically located between the left ventricle and the pulmonary circulation with important mechanical function (modulation of LV filling), which is closely coupled with its endocrine (atrial natriuretic peptide synthesis and secretion) and regulatory (contribution to the control of sympathetic activity and vasopressin release) functions. In this narrative review we provide evidence supporting the concept that left atrial dilation and systolic dysfunction (left atrial remodelling) contributes to the progression of asymptomatic LV dysfunction to chronic symptomatic systolic HF as it is a prerequisite for the development of the pulmonary congestion and marked neuronhormoral activity that characterize the symptomatic state.

Cardiac natriuretic peptides after myocardial infarction: relationship with infarct size, left ventricular function and remodelling assessed by 99mTc-sestamibi gated-single photon emission tomography

: The aim of the study was to investigate the potential relationship between A-type (atrial) and B-type (brain) natriuretic peptides (ANP, BNP) and infarct size (IS), left ventricular (LV) function and remodelling as assessed by 99m technetium-hexakis-2-methoxy-isobutyl-isonitrile (99mTc-sestamibi) gated-single photon emission tomography (G-SPET).

: Plasma concentrations of ANP and BNP in peripheral blood were measured in 54 patients with coronary artery disease (CAD) and previous myocardial infarction (MI). Of these, 25 subjects had a recent (<2 weeks) and 29 subjects an old (>6 months) MI. IS, left ventricular ejection fraction (LVEF) and end diastolic (EDV), end systolic (ESV) and stroke volume (SV) were quantitatively calculated from at-rest G-SPET.

: In either univariate or multivariate regression analysis that included IS and the other G-SPET derived parameters as co-variables, both BNP and ANP showed a significant association with IS (BNP p<0.002; ANP p<0.01). No significant relationship was found between the two peptides and LVEF, EDV or ESV values. BNP, but not ANP concentrations, were significantly higher in patients with antero-septal vs. infero-lateral (p=0.01) and recent vs. old MI (p=0.003). In these two subgroups, univariate and multivariate analyses confirmed the correlation between BNP and IS, whereas ANP demonstrated a relationship with IS only in subjects with recent MI. CAD extent had no influence on BNP and ANP levels.

: The present study showed a positive correlation between BNP and the perfusion defect measured by 99mTc-sestamibi G-SPET in patients with previous MI. Consequently, BNP may reflect the functional significance of myocardial damage and may be considered of prognostic value. ANP was also related to scintigraphic defects in the early phase after MI, but not in the chronic phase, confirming that ANP is a less sensitive marker of LV remodelling, depending also on atrial load conditions and dilatation. These preliminary data based on a small group of subjects need to be confirmed by prospective longitudinal studies involving larger populations.

Clin Chem Lab Med 2007;45:226–31.