B-type natriuretic peptide predicts sudden death in patients with chronic heart failure

Determinants of B-type natriuretic peptide plasma levels in the chronic phase after heart transplantation*

Determinants of B-type natriuretic peptide (BNP) plasma levels in the chronic phase after heart transplantation remain unclear. BNP was measured in 105 stable long-term heart transplant recipients with normal left ventricular function by echocardiography and correlated with clinical, demographic and hemodynamic parameters. Multivariate analysis revealed a significant correlation of BNP with female recipient gender (P = 0.006), time post-transplant (P =0.006), donor age (P = 0.007), angiographic signs of transplant vasculopathy (TVP) (P = 0.03), serum creatinine level (P = 0.04), and a strong trend for diastolic dysfunction (P = 0.09). Donor gender, recipient age, cyclosporin A blood levels, rejection history, and pulmonary artery pressure had no independent effect on BNP. BNP after heart transplantation appears to be influenced both by established general determinants (female gender, renal function) and transplant-specific determinants such as time post-transplant, donor age and potentially also TVP. In order to determine the value of BNP as a potential surrogate marker of TVP serial intraindividual measurements appear appropriate.

Cardiac natriuretic peptides for cardiac health

The cardiac natriuretic peptides, ANP (atrial natriuretic peptide) and BNP (brain natriuretic peptide), are secreted by the heart in proportion to cardiac transmural pressures. They possess a wide range of effects in multiple tissues facilitating overall pressure/volume homoeostasis. The close relationship between plasma concentrations of these peptides and 'cardiac load' has led to their use as biomarkers of cardiac health with diagnostic and prognostic applications in a variety of disorders affecting the cardiovascular system. BNP and its N-terminal fragment (NT-BNP) are especially sensitive indicators of cardiac dysfunction and remodelling, and correlate strongly with severity. Given that cardiac ischaemia is also an important trigger for the release of these ventricular peptides, they may likewise play a role in the detection of coronary artery disease. Measurement of BNP/NT-BNP shows particular promise as a 'rule out' test for suspected cases of HF (heart failure) in both emergency care and outpatient settings, and may assist in identifying individuals with asymptomatic ventricular impairment who will benefit from therapy preventing progression to overt HF. The BNP peptides also predict subsequent haemodynamic deterioration and adverse events in cardiovascular disease, and can therefore be used to monitor those at high risk and act as a guide to optimization of treatment. The favourable biological properties of the natriuretic peptides have also led to their use as therapeutic agents.

Elevated Brain Natriuretic Peptide Predicts Blood Pressure Response After Stent Revascularization in Patients With Renal Artery Stenosis

Background— A significant number (20% to 40%) of hypertensive patients with renal artery stenosis will not have blood pressure improvement after successful percutaneous revascularization. Identifying a group of patients with refractory hypertension and renal artery stenosis who are likely to respond to renal stent placement would be beneficial.

Methods and Results— Brain natriuretic peptide (BNP) was measured in 27 patients with refractory hypertension and significant renal artery stenosis before and after successful renal artery stent placement. This neuropeptide was elevated (median, 187 pg/mL; 25th to 75th percentiles, 89 to 306 pg/mL) before stent placement and fell within 24 hours of the successful stent procedure (96 pg/mL; 25th to 75th percentiles, 61 to 182 pg/mL; P =0.002), remaining low (85 pg/mL; 25th to 75th percentiles, 43 to 171 pg/mL) at follow-up. Clinical improvement in hypertension was observed in the patients with a baseline BNP >80 pg/mL (n=22) in 17 patients (77%) compared with 0% of the patients with a baseline BNP ≤80 pg/mL (n=5) ( P =0.001). After correction for glomerular filtration rate, BNP was strongly correlated with improvement in hypertension.

Conclusions— BNP is increased in patients with severe renal artery stenosis and decreases after successful stent revascularization. In addition, an elevated baseline BNP level of >80 pg/mL appears to be a good predictor of a blood pressure response after successful stent revascularization.

Understanding B-type natriuretic peptide and its role in diagnosing and monitoring congestive heart failure

Congestive heart failure (CHF) is a complex clinical syndrome characterized by dysfunction of the left, right, or both ventricles, which results in the impairment of the heart's ability to circulate blood at a rate sufficient to maintain the metabolic needs of peripheral tissues and various organs. Owing to the drastic increase in cardiovascular risk factors such as obesity, diabetes, and improved survival rate after acute myocardial infarction and subsequent development of CHF in the last quarter of a century, CHF has become a major and increasing cause of death and disability in the United States. Unfortunately, the signs and symptoms are nonspecific for CHF Also, routine laboratory values, electrocardiograms, and X-rays are not always accurate enough to make the appropriate diagnosis. Recently, the US Food and Drug Administration approved a new biomarker, B-type natriuretic peptide (BNP), for the purpose of diagnosing and assessing severity of CHE BNP is synthesized, stored, and released primarily by the ventricular myocardium in response to volume expansion and pressure overload. The use of SNP, along with other diagnostic tools, can enable care providers to facilitate and optimize care of heart failure patients in a variety of clinical settings. Emerging clinical data will help further refine biomarker-guided therapeutic and monitoring strategies involving BNP.

Neurohormonal risk stratification for sudden death and death owing to progressive heart failure in chronic heart failure

BACKGROUND

This study tested various neurohormones for prediction of heart failure death (death owing to progressive deterioration of ventricular function; HFD). Moreover, B-type natriuretic peptide (BNP) as a predictor of sudden death (SD; as reported previously) and the best predictor of HFD were combined for a simple risk stratification model.

DESIGN

BNP, the N-terminal fragment of BNP (N-BNP), and of the atrial natriuretic peptide (N-ANP) and big endothelin levels were obtained from 452 patients with a left ventricular ejection fraction </= 35%. Outcome was documented during an observation period up to 3 years.

RESULTS

Two hundred and ninety-eight patients survived without heart transplantation, 65 patients underwent heart transplantation and 89 patients died (SD 44 patients, HFD 31 patients, other causes 14 patients). The only independent predictor of SD was BNP (as reported), and the best independent predictor of HFD was N-ANP (P = 0.0001). Analyzing 293 survivors and 44 patients with SD, fewer patients with BNP < 130 pg mL(-1) (Group A, n = 110) died [1%] as compared with patients with BNP > 130 pg mL(-1) and N-ANP < 6300 fmol mL(-1) (Group B, n = 177; 18%; P = 0.0001) and patients with BNP > 130 pg mL(-1) and N-ANP > 6300 fmol mL(-1) (Group C, n = 50; 19%; P = 0.0001). Analyzing 293 survivors and 31 patients with HFD, fewer patients died in Group A (n = 109; 0%; P = 0.0001) and Group B (n = 153; 6%; P = 0.0001) as compared with patients of Group C (n = 62; 34%).

CONCLUSION

Prognostic power of neurohormones depends on the mode of death. The combined determination of BNP and N-ANP identifies patients with minimal risk of death, elevated SD but low HFD risk as well as elevated SD and HFD risk.

Biomarkers of cardiac disease

The challenge of medical practice today is to identify individuals who are at risk of developing disease, determine the severity of the disease and distinguish the responders from the nonresponders to therapy (individualized medicine). Advances in molecular genetics and biology have shifted the paradigm for identification of markers from large-scale epidemiologic studies to studies on genomic- and proteomic-based techniques. Consequently, a large number of biologic markers, referred to as biomarkers, are being identified and validated to serve for risk stratification, prognostication and individualization of therapy. Identification of biomarkers for cardiovascular diseases could also provide insight into the pathogenesis of the phenotype, which is fundamental for the development of specific therapies. The list of biomarkers for cardiovascular disease is expanding rapidly. Nonetheless, the field is in the early stages of evolution and large-scale clinical studies are required to validate the utility of newly identified biomarkers in diagnosis, risk stratification and treatment of cardiovascular diseases. Selected biomarkers for coronary atherosclerosis, acute coronary syndromes and heart failure are discussed in this review.

Natriuretic peptides and the prevalence of congestive heart failure in patients with pacemakers

AIM

The aim of the study was to investigate the diagnostic potential of natriuretic cardiac peptide measurement in the context of left ventricular dysfunction and comorbidities in a pacemaker population.

MATERIAL AND METHODS

Ninety-five consecutive patients with pacemakers were included in the study. All patients underwent echocardiography and were asked to complete the Minnesota Living with Heart Failure Questionnaire (MLHFQ). Brain natriuretic peptide (BNP), N-terminal proatrial natriuretic peptide (N-ANP) and atrial natriuretic peptide levels in plasma were measured.

RESULTS

Twenty-six percent of patients had reduced systolic left ventricular function; only 16 patients had a history of congestive heart failure. BNP was abnormally elevated in 64%, N-BNP in 72% and N-ANP in 96% of patients. Both BNP (r = 0.30; P < 0.01) and N-ANP (r = 0.39; P < 0.0005) correlated with MLHFQ. The strongest correlation was found between N-ANP and the ejection fraction (r = 0.6; P < 0.0001). Patients were stratified in a high-risk group and a low risk-group according to their N-ANP (N-ANP > 5000 fmol L(-1); n = 63 and N-ANP < 5000 fmol L(-1), n = 32) and BNP levels (BNP > 400 pg mL(-1); n = 17 and BNP < 400 pg mL(-1), n = 78). N-ANP was correlated with hypertension (P < 0.003) and atrial fibrillation (P < 0.03), and BNP with mitral insufficiency (P < 0.002).

CONCLUSIONS

Cardiac natriuretic peptides are markedly elevated in the majority of patients with pacemakers. The prognostic significance of BNP and N-ANP in left ventricular dysfunction warrants close follow-up schedules.

Analysis of chronic heart failure registry in the Tohoku district: third year follow-up

BACKGROUND

Because the real prognosis of Japanese patients with chronic heart failure (CHF) is still unknown, the aim of the present study was to clarify the prognosis and predictors for mortality of CHF patients using the Chronic Heart failure Analysis and Registry in Tohoku district (CHART).

METHODS AND RESULTS

As of February 2003, 1,154 stable CHF patients with optimum standard therapy have been enrolled in the registry since February 2000 and of these, 175 died of some cause during the follow-up period (mean follow-up period, 1.9+/-0.9 years), giving 1- and 3-year all-cause mortality rates of 7.3% and 20.9%, respectively. Multivariate analysis showed that age at entry, diabetes, ventricular tachycardia, plasma concentration of brain natriuretic peptide (BNP), New York Heart Association (NYHA) functional class and rural residence were significantly associated with all-cause mortality (hazard ratio: 1.028, 1.940, 1.650, 1.001, 1.713, and 2.226). The 1-year all-cause mortality rates of CHF patients with a left ventricular ejection fraction <25%, left ventricular end-diastolic diameter > or =60 mm, BNP > or =500 pg/ml, NYHA > or = III, or with underlying coronary artery disease were 15.0%, 11.4%, 16.8%, 16.3%, and 10.8%, respectively.

CONCLUSIONS

The prognosis of Japanese CHF patients with these predictors remains poor. A stratified approach is necessary to improve their survival and quality of life.

A Novel Data Mining Approach to the Identification of Effective Drugs or Combinations for Targeted Endpoints?Application to Chronic Heart Failure as a New Form of Evidence-based Medicine

BACKGROUND

Data mining is a technique for discovering useful information hidden in a database, which has recently been used by the chemical, financial, pharmaceutical, and insurance industries. It may enable us to detect the interesting and hidden data on useful drugs especially in the field of cardiovascular disease.

METHODS AND RESULTS

We evaluated the current treatments for chronic heart failure (CHF) in our institute using a decision tree method of data mining and compared the results with those of large-scale clinical trials. We enrolled 1,100 patients with CHF (NYHA classes II-IV and EF < 40%) who were hospitalized at the National Cardiovascular Center during the past 31 months. Drugs prescribed at discharge were extracted from the clinical database. Both echocardiograms and plasma BNP level at 6-12 months after discharge were determined prospectively. It was found that beta-blockers, angiotensin converting enzyme inhibitors, and angiotensin II receptor antagonists independently improve both the plasma BNP level and %fractional shortening (FS), while oral inotropic agents increased the plasma BNP level and decreased %FS. These findings agree with evidence accumulated from several large-scale trials. Interestingly, statins, histamine receptor blockers, and alpha-glucosidase inhibitors also attenuated the severity of CHF, suggesting the possibility of new treatment of CHF.

CONCLUSION

Clinical data mining using Japanese CHF patients yielded almost identical data to the results of large-scale trials, and also suggested novel and unexpected candidates for CHF therapy. Further validation of the data mining approved in the cardiovascular field is warranted.

Natriuretic peptides BNP and NT-pro-BNP: established laboratory markers in clinical practice or just perspectives?

A growing body of literature describes diagnostic and prognostic value of B-type natriuretic peptides (BNP) in cardiac diseases since it was first described in 1988. As BNP is mainly secreted in the left ventricular (LV) myocardium, BNP was found to reflect LV function much better than any other neurohumoral factor. Thus, BNP is recommended as the first noninvasive blood test for determination of cardiac function by some authors. The introduction of fully automated, rapid bioassays for measurement of BNP and the aminoterminal part of its pro-hormone (NT-pro-BNP) made it possible to use the test even in emergency care settings. Here we review the literature with special focus on assessment of BNP and NT-pro-BNP in the following clinical settings: community screening for LV dysfunction, primary diagnosis of heart failure in general practice and emergency department (ED) and risk stratification in cardiac dysfunction and acute coronary syndromes. In addition, we discuss which applications can be recommended for daily clinical use from the cardiologist's point of view.

Ventricular Dysrhythmias in Heart Failure

Left-ventricular systolic dysfunction, or heart failure (HF), is a chronic, progressive condition with a poor prognosis. Approximately 50% of deaths, especially in mild to moderate cases, are sudden. Most sudden deaths are thought to be due to ventricular tachycardia; however, premature ventricular contractions and couplets parallel severity of HF and have been associated with increased mortality risk as opposed to dysrhythmic death. Ventricular arrhythmogenesis results from many mechanisms (afterdepolarizations, reentry, and enhanced automaticity) and preconditions (electrophysiologic abnormalities, neuroendocrine activation, electrolyte imbalances, scar from an ischemic event in ischemic cardiomyopathy, fibrosis in dilated cardiomyopathy, hemodynamic abnormalities, and HF medical management). Nurses are key caregivers in optimally managing HF, either by direct actions or by using advocacy, communication, and collaboration skills to promote positive outcomes. Ventricular dysrhythmia management consists of facilitating core HF pharmacologic and nonpharmacologic medical therapies, using amiodarone to improve symptoms, as needed, and utilizing implantable cardioverter-defibrillator therapy to reduce the risk of sudden cardiac death.

Abnormalities of Neurohormonal and Cardiac Autonomic Nervous Activities Relate Poorly to Functional Status in Fontan Patients

Background— Impaired cardiac autonomic nervous activities and increased neurohumoral activities (CANA, NHA) characterize Fontan patients. However, the clinical significance of these changes is not clearly understood. Our purpose was to clarify the clinical significance of the CANA and NHA in stable Fontan patients.

Methods and Results— We divided 22 atriopulmonary connection (APC) and 75 total cavopulmonary connection (TCPC) patients into 4 subgroups according to New York Heart Association (NYHA) class (1.8±0.6) and measured various CANA and NHA indices. All NHA indices were elevated in the symptomatic patients ( P <0.001). Natriuretic peptides were higher in the APC than in the TCPC patients, and the hemodynamics showed no correlation with brain natriuretic peptide in the APC patients. Low arterial oxygen saturation and impaired hemodynamics greatly influenced all elevated NHA indices ( P <0.01), except for plasma renin activity, in the TCPC patients. Impaired CANA indices did not relate to NYHA class, although surgeries were associated with lower heart rate variability. In addition to poor correlation between NHA and CANA, age and ventricular morphology had no impact on all CANA and NHA indices, except for high norepinephrine in right ventricular Fontan patients.

Conclusions— Although symptomatic Fontan patients exhibit higher NHA, CANA is not related to either NYHA class or NHA. APC itself is responsible for higher natriuretic peptides, and arterial oxygen desaturation has a great impact on elevated NHA in the TCPC patients. These characteristics of the NHA and CANA differ from those of heart failure patients with biventricular physiology.

Very low frequency power of heart rate variability is a powerful predictor of clinical prognosis in patients with congestive heart failure

BACKGROUND

The present study examined whether the very low frequency (VLF) power of heart rate variability (HRV) is predictive of clinical prognosis in patients with congestive heart failure (CHF).

METHOD AND RESULTS

The study recruited 54 consecutive CHF patients with emergency admission because of exacerbation of pulmonary congestion. Holter monitoring was performed after improvement of pulmonary congestion. The frequency components of HRV were calculated in the frequency domain (VLF, low frequency (LF), high frequency (HF), total power (TP) and the ratio of LF to HF power). The left ventricular ejection fraction was calculated, and plasma brain natriuretic peptide (BNP) and norepinephrine were also measured at discharge. Within a mean follow-up period of 19.8 +/- 11.7 months, 18 patients experienced cardiovascular events; 7 patients died and 11 patients required rehospitalization because of worsening of CHF. In univariate analysis, diabetes mellitus (DM), BNP and New York Heart Association (NYHA) functional class were significant as risk factors for cardiac events. VLF power, LF power and TP were the strong predictors for cardiac events in HRV. In multivariate analysis, VLF power predicted cardiac events independently of LF power, TP, DM, BNP and NYHA functional class (chi-square=6.24, p=0.01).

CONCLUSIONS

VLF power is an independent risk predictor in patients with CHF.

Predicting sudden death in patients with mild to moderate chronic heart failure

OBJECTIVES

To explore the relation between non-invasive measures of cardiac function and sudden cardiac death, as well as the development and utility of an index integrating these variables to identify patients at increased risk of this mode of death.

DESIGN

UK-HEART (United Kingdom-heart failure evaluation and assessment of risk trial) was a prospective study conducted between December 1993 and April 2000. The study was specifically designed to identify non-invasive markers of death and mode of death among patients with chronic heart failure.

SETTING

8 UK general hospitals.

MAIN OUTCOME MEASURES

Death and mode of death.

RESULTS

553 patients aged a mean (SD) of 63 (10) years, in New York Heart Association functional class 2.3 (0.02), recruited prospectively. After 2365 patient-years' follow up, 201 patients had died (67 suddenly). Predictors of sudden death were greater cardiothoracic ratio, QRS dispersion, QT dispersion corrected for rate (QTc) across leads V1-V6 on the 12 lead ECG, and the presence of non-sustained ventricular tachycardia. The hazard ratio and 95% confidence intervals (CI) of sudden death for a 10% increase in cardiothoracic ratio was 1.43 (95% CI 1.20 to 1.71), for a 10% increase in QRS dispersion 1.11 (95% CI 1.04 to 1.19), for the presence of non-sustained ventricular tachycardia 2.03 (95% CI 1.27 to 3.25), and for a 10% increase in QTc dispersion across leads V1-V6 1.03 (95% CI 1.00 to 1.07) (all p < 0.04). An index derived from these four factors performed well in identifying patients specifically at increased risk of sudden death.

CONCLUSIONS

Results show that an index derived from three widely available non-invasive investigations has the potential to identify ambulant patients with chronic heart failure at increased risk of sudden death. This predictive tool could be used to target more sophisticated investigations or interventions aimed at preventing sudden death.

Natriuretic peptide system: physiology and clinical utility

PURPOSE OF REVIEW

This review discusses the physiology of natriuretic peptides as a group and brain natriuretic peptide (BNP) in more detail. It will also highlight implications for the use of the natriuretic peptides in the diagnosis and treatment of patients with cardiovascular disease.

RECENT FINDINGS

The heart secretes two major natriuretic peptides: atrial natriuretic peptide (ANP), which is synthesized in the atrial myocardium, and BNP, which is synthesized in the ventricular myocardium. Both ANP and BNP are released in response to atrial and ventricular stretch, respectively, and will cause balanced vasodilation, natriuresis, and inhibition of the sympathetic nervous system and the renin-angiotensin-aldosterone axis. BNP is reported to be the biochemical marker of choice for evaluating the acute risk of patients with cardiovascular disease states ranging from heart failure to myocardial ischemia. Increased blood BNP concentrations are highly predictive of the short- and long-term risk of cardiac death across the entire spectrum of acute coronary syndromes and in patients with decompensated congestive heart failure. Synthetic recombinant human BNP, which mimics the actions of endogenous BNP, has emerged as an important new therapeutic agent in patients with acute heart failure.

SUMMARY

Current data suggest that single and serial plasma measurement of BNP concentrations is a useful tool in the diagnosis and risk stratification of patients with heart disease. Nesiritide, the human recombinant form of BNP, is a new promising parenteral treatment in decompensated heart failure.

Plasma Level of B-Type Natriuretic Peptide as a Prognostic Marker After Acute Myocardial Infarction

Background— Circulating levels of B-type natriuretic peptide (BNP), a cardiac hormone, reflect the severity of cardiac dysfunction. Because the plasma BNP level changes dramatically during the period after the onset of acute myocardial infarction (AMI), identification of a suitable sampling time is problematic. There have been several reports indicating that the plasma BNP level obtained in the acute phase of AMI can be used as a prognostic marker. We examined whether the plasma BNP level measured 3 to 4 weeks after the onset of AMI represents a reliable prognostic marker for patients with AMI.

Methods and Results— We analyzed 145 consecutive patients with AMI. Plasma BNP levels were measured during the 3 to 4 weeks after onset of AMI. Of those patients, 23 experienced fatal cardiac events during this study. The mean follow-up period was 58.6 months. Log BNP, left ventricular end-diastolic pressure, and pulmonary vascular resistance were all significantly higher in the cardiac death group, and there were more men and more patients with a history of heart failure in the cardiac death group. A Cox proportional hazards model analysis showed that log BNP was an independent predictor of cardiac death. The survival rate was significantly higher in patients with log BNP <2.26 (180 pg/mL) than in those with log BNP ≥2.26.

Conclusions— The plasma BNP level obtained 3 to 4 weeks after the onset of AMI can be used as an independent predictor of cardiac death in patients with AMI.

Measuring plasma B-type natriuretic peptide in heart failure: good to go in 2004?

Elevated plasma brain natriuretic (BNP) concentrations correlate with increased cardiac filling pressures. Therefore, increased BNP has been proposed as a marker for asymptomatic ventricular dysfunction, as an aid in the diagnosis of cardiac dyspnea, as an end point to assess the efficacy of heart failure therapy, and as a prognostic marker in heart failure. An understanding of the utility of BNP requires an appreciation of the sensitivity, specificity, and diagnostic accuracy of BNP in each of these clinical situations. At this time, there is strong evidence for the value of BNP in the evaluation of dyspnea of uncertain cause. Further population studies will need to be performed to refine the application of BNP to community cohorts and to determine its clinical value and cost-effectiveness as a screening tool in the early diagnosis of ventricular dysfunction. To make optimal use of BNP for the assessment of heart failure therapy and prognosis in individual patients, physicians will require additional information on the biological variability of BNP. Studies comparing the sensitivity, specificity, and predictive value of the available BNP and N-terminal pro-BNP assays need to be conducted in each of these clinical settings.

BNP Consensus Panel 2004: A Clinical Approach for the Diagnostic, Prognostic, Screening, Treatment Monitoring, and Therapeutic Roles of Natriuretic Peptides in Cardiovascular Diseases

Among the most exciting developments in the field of heart failure in recent times has been the rediscovery of the natriuretic peptide system and its pleuripotent effects on cardiac structure and function. This is particularly true of its natriuretic and hemodynamic effects. There has been an explosion of the knowledge base seeking to understand the wide range of homeostatic, regulatory, and counter-regulatory functions in which the natriuretic peptide system participates. Additional interest has been stimulated by advances in technology such as point-of-care and core laboratory BNP assays and the use of the recombinant B-type natriuretic peptide nesiritide as a treatment option. Despite this recent interest, the available literature lacks a comprehensive expert review of the current science and roles of natriuretic peptides for diagnostic, prognostic, screening, treatment monitoring, and therapeutic purposes. More importantly, a summary updating and guiding the clinician on most of these advances was lacking. An expert Consensus Panel with basic, methodological, and clinical expertise was convened to summarize current knowledge in these areas and the findings and consensus statements are contained herein.

Is plasma N-BNP a good indicator of the functional reserve of failing hearts? The FRESH-BNP study

AIMS

Whether plasma N-terminal brain natriuretic peptide (N-BNP) is useful in the diagnosis of heart failure (HF) depends traditionally on whether it is as good as the putative 'gold-standard', left ventricular ejection fraction (LVEF), in indicating cardiac dysfunction. However, since HF is primarily an impairment of function of the cardiac pump, we explored the relationship between N-BNP and direct and indirect indicators of cardiac pump dysfunction.

METHODS AND RESULTS

Eighty-six HF patients (mean age 56 years) with a range of LVEF's (mean 36.9+/-15.2%, range 15-66%) and 10 age-matched healthy controls were recruited into the study and had resting N-BNP measured. Cardiopulmonary exercise testing was performed to assess peak oxygen consumption (Vo(2)). A subgroup of 23 subjects underwent further exercise haemodynamic assessment to evaluate peak cardiac power output (CPO). The CHF group had significantly higher N-BNP (median [interquartile range]) levels (299 [705] fmol/ml) than the control group (7 [51] fmol/ml, P<0.005). Significant correlations between N-BNP and peak Vo(2), and N-BNP and peak CPO were observed (R> or =0.5, P<0.005). Although significant correlation was observed between N-BNP and LVEF (R=0.34, P=0.01), the correlations between LVEF and peak Vo(2) or peak CPO (all R<0.3, P>0.3) were not significant. Multivariate analysis identified plasma N-BNP and NYHA class, but not LVEF, as independent predictors of peak Vo(2).

CONCLUSIONS

We have found that N-BNP was surprisingly good as a simple indicator of cardiac pump dysfunction. Since heart failure is an inadequacy of function, these results strongly support the notion that N-BNP is a useful blood test in estimating the extent of cardiac pump dysfunction and helpful in establishing positive diagnosis of heart failure.

Utility of B-type natriuretic peptide for the evaluation of intensive care unit shock*

OBJECTIVES

Among patients with congestive heart failure, B-type natriuretic peptide measurement is useful to estimate filling pressures and to prognosticate adverse outcome. However, among critically ill intensive care unit patients with shock, the utility of B-type natriuretic peptide to assess cardiac hemodynamics or prognosis has not been explored.

DESIGN

Clinical investigation.

SETTING

Hospital.

PATIENTS

Forty-nine patients with shock and indication for pulmonary artery catheterization.

INTERVENTIONS

Analysis for B-type natriuretic peptide was performed on blood obtained at the time of catheter placement.

MEASUREMENTS AND MAIN RESULTS

Correlations between B-type natriuretic peptide and pulmonary artery occlusion pressure as well as cardiac index were calculated using Spearman analysis. Mortality at the time of study completion was correlated with B-type natriuretic peptide values and Acute Physiology and Chronic Health Evaluation II scores, and logistic regression identified independent predictors of mortality. A wide range of B-type natriuretic peptide concentrations was seen in intensive care unit patients (<5 to >5000 pg/mL); only eight patients (16%) had normal B-type natriuretic peptide concentrations. Log-transformed B-type natriuretic peptide concentrations did not correlate with interpatient cardiac index or pulmonary artery occlusion pressure (all p = not significant); however, a B-type natriuretic peptide <350 pg/mL had a negative predictive value of 95% for the diagnosis of cardiogenic shock. Median B-type natriuretic peptide concentrations were higher in those who died than those who survived (943 pg/mL vs. 378 pg/mL, p <.001). In multivariable analysis, a B-type natriuretic peptide concentration in the highest log-quartile was the strongest predictor of mortality (odds ratio = 4.50, 95% confidence interval = 1.87-99.0, p <.001).

CONCLUSION

B-type natriuretic peptide concentrations are frequently elevated among critically ill patients in the intensive care unit and cannot be used as a surrogate for pulmonary artery catheterization. B-type natriuretic peptide concentrations in intensive care unit shock may provide powerful information for use in mortality prediction.

Interleukin-6 and B-type natriuretic peptide are independent predictors for worsening of heart failure in patients with progressive congestive heart failure

BACKGROUND

Neurohormones and cytokines have been associated with poor prognosis in patients with congestive heart failure. However, direct comparisons between them are rare and the best predictor for worsening of heart failure remains to be elucidated. The aim of the study was to identify independent predictors for worsening of heart failure.

METHODS

We studied 100 patients with congestive heart failure (LVEF <or=25%). Serum levels of interleukin-6 (IL-6), tumor necrosis factor (TNF)-alpha, aminoterminal atrial natriuretic peptide (N-ANP), B-type natriuretic peptide (BNP), aminoterminal B-type natriuretic peptide (N-BNP), norepinephrine (NE) and big endothelin (big ET) were measured at entry into the study. Univariate and stepwise multivariate regression analyses were performed to compare variables and clinical parameters. The end-point was defined as worsening of heart failure.

RESULTS

During follow-up (mean 378 days), 30 patients reached the defined end-point. Univariate risk factors of worsening of heart failure were IL-6 (p = 0.0001), log BNP (p = 0.0001), log N-ANP (p = 0.0259), big ET (p = 0.0032), log N-BNP (p = 0.0495), NE (p = 0.0013) and LVEF (p = 0.0498). Multivariate regression analysis identified IL-6 as the strongest independent predictive value for worsening of heart failure (p = 0.0001), followed by log BNP (p = 0.0002). Mean IL-6 levels were 1.76 +/- 1.73 in stable patients and 4.62 +/- 7.98 pg/ml in patients who developed worsening of heart failure. Using a cut-off value of 1.66 pg/ml for IL-6 Kaplan-Meier freedom from worsening, heart failure was significantly higher in patients below this cut-off point compared with those above (p = 0.0002).

CONCLUSIONS

IL-6 and BNP independently predict worsening of heart failure. A single measurement could help to identify patients at high risk for worsening of heart failure and these individuals should be monitored more closely.

Utility of B-type natriuretic peptide in differentiating congestive heart failure from lung disease in pediatric patients with respiratory distress

Plasma B-type natriuretic peptide (BNP) has been reported to be helpful in differentiating cardiac from pulmonary etiologies of dyspnea in adults. We investigated whether BNP concentration could be applied similarly in children with respiratory distress. BNP levels were measured using a rapid immunoassay in 49 infants and children presenting with acute respiratory distress. The patient's history, symptoms, physical exam, chest x-ray, and an echocardiogram were used to identify patients with congestive heart failure (CHF) from noncardiac causes of respiratory distress. Results are reported as mean+/-SD. Patients with CHF (n = 23) had BNP levels of 693.0+/-501.6 pg/ml, significantly higher than those of the group of patients with lung disease (n = 26), whose BNP was 45.2+/-64.0 pg/ml (p < 0.001). There was no significant difference in age between the two groups (29.7+/-59.3 vs 13.1+/-22.6 months; p = 0.12). A BNP level of 40 pg/ml was 84% accurate in differentiating CHF from pulmonary disease. Fifteen of 23 CHF patients had ventricular volume overload from left-to-right shunting congenital heart defects and 8/23 had left ventricular systolic dysfunction. Age-adjusted comparison of the two subgroups of CHF patients revealed that children with left ventricular systolic dysfunction had significantly higher mean BNP levels than those with left-to-right shunts (1181+/-487 vs 433+/-471 pg/ml, p = 0.0074). We conclude that BNP level is of value in differentiating cardiac from pulmonary causes of respiratory distress in children.

NT-proBNP and BNP: biomarkers for heart failure management

Guidelines for the pharmacological treatment of heart failure (HF) are based on results from large clinical trials demonstrating benefit. State of the art pharmacological management of HF assumes that target doses should be the same as those used in trials. Thus equal doses are recommended for all in practical guidelines, but this strategy might not fit individual needs. NT-proBNP and BNP emerged as potential biomarkers of clinical interest in HF management. NT-proBNP and BNP are related to HF severity and to clinical status. NT-proBNP and BNP are strongly associated with prognosis across the whole spectrum of HF patients. A pilot study has shown that NT-proBNP-guided therapy is associated with improved outcome in HF. Although at present there are still few data to make firm recommendations on the use of NT-proBNP or BNP levels as biomarkers for HF management, future studies will provide further insight on this issue.

B-type natriuretic peptide: practical diagnostic use for evaluating ventricular dysfunction

Assessment of brain natriuretic peptide levels may provide important information that can be used in the evaluation of patients with dyspnea and follow-up of heart failure. Brain natriuretic peptide levels have been shown to be useful for evaluating patients in the emergency department and for evaluating patients complaining of dyspnea in the outpatient setting. Brain natriuretic peptide assessment also provides an adjunct to diagnosis of both systolic and diastolic dysfunction, has prognostic value for heart failure and in acute coronary syndromes, and may be a useful measure to guide therapy. Further work needs to be done to establish the best type of assay to use, to determine the optimal cutoff point for what is considered abnormal, and to determine how conditions other than ventricular dysfunction affect brain natriuretic peptide levels.

Implications of the natriuretic peptide system in the pathogenesis of heart failure: diagnostic and therapeutic importance

The natriuretic peptide family consists of at least 3 structurally similar peptides: atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and C-type natriuretic peptide (CNP). Under normal conditions, ANP is synthesized by the atrium and released in response to atrial stretch. This peptide plays an important role in sodium and water homeostasis and is involved in cardiovascular function. In contrast, BNP is synthesized primarily by the ventricles, and its circulatory concentrations are significantly elevated in profound congestive heart failure (CHF). While both plasma levels of ANP and BNP have been found to be increased in patients with various heart diseases, the elevation in circulatory BNP correlates better than ANP with the severity of CHF. Therefore, plasma BNP has been suggested (and lately used) to aid in the accurate diagnosis of heart failure in patients admitted to the emergency room with symptoms of decompensated heart failure. Furthermore, circulatory BNP has been utilized as a prognostic marker in CHF as well as a hormone guide in the evaluation of the efficacy of the conventional treatment of this disease state. In light of the cardiovascular and renal effects of BNP, which most likely exceed those of ANP, the former has been used as a therapeutic agent for the treatment of patients with acute severe CHF. Intravenous infusion of BNP into patients with sustained ventricular dysfunction causes a balanced arterial and venous vasodilatation that has been shown to result in rapid reduction in ventricular filling pressure and reversal of heart failure symptoms, such as dyspnea and acute hemodynamic abnormalities. Thus, the goal of this article is to review the physiology and pathophysiology of natriuretic peptides and the potential use of their circulating levels for diagnosis and treatment of heart failure.

What price support? Ventricular assist device induced systemic response

Use of ventricular support systems has been associated with myriad systemic complications. Engendered by the blood-biomaterial interface of a unique host/device relationship, these complications include diverse humoral dyscrasias that frequently culminate in episodes of bleeding, hemolysis and thrombogenicity, heightened susceptibility to inflammation and infection, and transient immunal compromise. Recent endeavor in biocompatibility research has served to illustrate the critical role played by cellular, humoral, and neurohormonal components in regulating cytokine expression and has provided insight into the complexities involved in such biomechanical juxtapositions. The following is intended as a review of current literature attempting to address the many aspects of this host/device interaction and their consequences for the supported patient.

Usefulness of the third heart sound in predicting an elevated level of B-type natriuretic peptide

Third heart sounds were sought in 100 consecutive outpatients who had B-type natriuretic peptide (BNP) levels measured within 8 hours. Mean BNP levels were significantly higher in those with a third heart sound. The presence of a third heart sound was 41% sensitive and 97% specific for elevated BNP levels.

B-type natriuretic peptide: the level and the drug--partners in the diagnosis of congestive heart failure

Over the past 100 years, cardiovascular disease has become a leading cause of morbidity and mortality worldwide. A tremendous increase in incidence and prevalence of heart failure has been observed in the United States. The cost of managing heart failure itself is $56 billion a year, 70% of which is due to hospitalization. Although we have made tremendous advances in our understanding of the pathophysiology and treatment of congestive heart failure, the diagnosis of the disease still remains difficult. Unfortunately, the signs and symptoms of congestive heart failure are nonspecific. The recognition of the role of B-type natriuretic peptide as an objective marker for the diagnosis, severity, and prognosis of acute coronary syndromes and congestive heart failure was truly a breakthrough for clinicians and patients faced with cardiovascular disease. Also, the high levels of endogenous B-type natriuretic peptide may be released as a "distress hormone"; that is, these levels are no longer effective in maintaining the balance of vasoconstriction and vasodilation. Hence it makes intuitive and practical sense that giving back B-type natriuretic peptide in the form of exogenous nesiritide might restore neurohormonal homeostasis. Therefore, lately there has been a lot of interest shown in the use of recombinant B-type natriuretic peptide as a drug. This article reviews the literature concerning the use of these peptides in a variety of clinical scenarios and the use of recombinant B-type natriuretic peptide in decompensated heart failure.

Recent advances in the diagnosis of heart failure

Heart failure has reached epidemic proportions and the prevalence is increasing. The accurate and efficient diagnosis of heart failure remains problematic, as signs and symptoms are neither sensitive nor specific. Recent advances in the diagnosis of this condition include a conceptual change in what constitutes heart failure, a greater understanding of heart failure with preserved systolic function, and an abundance of data supporting the use of neurohormonal assays, particularly brain-type natriuretic peptide. These factors will help facilitate earlier diagnosis and targeted treatment of patients with this malady.

Natriuretic peptides predict symptom-free survival and postoperative outcome in severe aortic stenosis

BACKGROUND

The prognostic value of natriuretic peptides in aortic stenosis (AS) remains unknown.

METHODS AND RESULTS

B-type natriuretic peptide (BNP), N-terminal BNP (NtBNP), and N-terminal atrial natriuretic peptide (NtANP) were determined in 130 patients with severe AS (mean age, 70+/-12 years; mean gradient, 64+/-21 mm Hg; valve area, 0.64+/-0.15 cm2) who were followed up for 377+/-150 days. Natriuretic peptides increased with NYHA class and with decreasing ejection fraction (EF). Even asymptomatic patients frequently had elevated neurohormones. Asymptomatic patients who developed symptoms during follow-up had higher BNP and NtBNP levels at entry compared with those remaining asymptomatic (median for NtBNP, 131 pmol/L [interquartile range, 50 to 202 pmol/L] versus 31 pmol/L [range, 19 to 56 pmol/L]; P<0.001). Symptom-free survival at 3, 6, 9, and 12 months for patients with NtBNP <80 versus > or =80 pmol/L was 100%, 88+/-7%, 88+/-7%, and 69+/-13% compared with 92+/-8%, 58+/-14%, 35+/-15%, and 18+/-15%, respectively (P<0.001). Seventy-nine patients eventually underwent surgery because of symptoms. Considering preoperative neurohormone levels, age, NYHA class, aortic valve area, EF, and presence of coronary artery disease, we found that neurohormones, EF, and NYHA class predicted survival; neurohormones predicted postoperative symptomatic status; and neurohormones and preoperative EF predicted postoperative EF. However, by multivariate analysis, NtBNP was the only independent predictor of outcome.

CONCLUSIONS

In severe AS, natriuretic peptides provide important prognostic information beyond clinical and echocardiographic evaluation. NtBNP independently predicts symptom-free survival, and preoperative NtBNP independently predicts postoperative outcome with regard to survival, symptomatic status, and left ventricular function. Thus, neurohormones may gain particular importance for timing of surgery in asymptomatic severe AS.

Risk stratification and management of sudden cardiac death: a new paradigm

Risk Stratification and Management of SCD. Management of SCD is undergoing radical change in direction. It is becoming increasingly appreciated that besides depressed left ventricular systolic function and the conventional risk stratification tools, new markers for plaque vulnerability, enhanced thrombogenesis, specific genetic alterations of the autonomic nervous system, cardiac sarcolemmal and contractile proteins, and familial clustering may better segregate patients with atherosclerotic coronary artery disease who are at high risk for SCD from those who may suffer from nonfatal ischemic events. Better understanding of pathophysiologic processes, such as postmyocardial infarction remodeling, the transition from compensated hypertrophy to heart failure, and the increased cardiovascular risk of coronary artery disease in the presence of diabetes or even a prediabetic state will help to improve both risk stratification and management. The rapidly developing fields of microchips technology and proteomics may allow rapid and cost-effective mass screening of multiple risk factors for SCD. The ultimate goal is to identify novel methods for risk stratification, risk modification, and prevention of SCD that could be applied to the general public at large.

EFFECT OF ACUTE BRAIN DEATH ON RELEASE OF ATRIUM AND B-TYPE NATRIURETIC PEPTIDES IN AN ANIMAL MODEL

INTRODUCTION

Atrium and B-type natriuretic peptides (ANP and BNP) and big endothelin (ET)-1 are markers for severity of heart failure and may be used in the quality assessment of donor hearts. Elevated cardiac troponins predict early graft failure after heart transplantation. This study evaluated the effects of acute brain death (BD) on the release of ANP, BNP, big ET-1, and cardiac troponins in an animal model.

MATERIALS AND METHODS

Pigs were randomized into a BD group (n=5) and a control group (n=5). In the first group, acute BD was induced, and anesthesia was stopped. In the control animals, a sham operation was performed, and anesthesia was continued. Parameters were measured at baseline and for 13 hours postoperatively.

RESULTS

After acute BD, there were significant hemodynamic changes. In the control group, the BNP level was higher than in the BD group and decreased over time (P =0.016). There was no significant change in BNP release in the BD group up to 13 hours (P =0.1). ANP release remained stable over time in the control group (P =0.35) but decreased in the BD group (P =0.043). The big ET-1 levels were not different between groups. Cardiac troponin I was elevated in the BD group 5 hours after BD (P< 0.05) but remained under 1.5 mg/L throughout the study.

CONCLUSION

Acute BD did not lead to an increase of BNP and ANP levels. Moreover, intact brain function seems to augment the release of natriuretic peptides from the myocardium. Further clinical evaluation of prognostic values of natriuretic peptides for the assessment of donor hearts is necessary. Cardiac troponins are a useful additional tool in the evaluation of donor hearts.

Guidelines for Acute Decompensated Heart Failure Treatment

OBJECTIVE

To describe the development of guidelines for the treatment of acute decompensated heart failure (ADHF) in the emergency department/observation unit (ED-OU) setting for hospitals that are part of a group purchasing organization (GPO).

DATA SOURCES

A MEDLINE search (1966-March 2003) using the following search terms: cardiotonic agents; diuretic; dobutamine; heart failure, congestive; milrinone; natriuretic peptide, brain; nesiritide; nitroglycerin; vasodilator agents, was conducted.

STUDY SELECTION AND DATA EXTRACTION

Relevant articles in the English language were identified. All randomized studies and meta-analyses for each category of drugs were included.

DATA SYNTHESIS

A group consensus method was used to develop guidelines. An expert panel reviewed and revised the guidelines. The final guidelines were approved June 1, 2003, and are described here. They are organized based upon a patient's symptomatology at the time the diagnosis of ADHF is made. Patients with evidence of volume overload require intravenous diuretics and/or intravenous vasodilators to alleviate the symptoms of ADHF. Patients with signs and symptoms of low cardiac output require inotropic support to manage their ADHF. A timeline for diagnosis, treatment, reassessment, and disposition is provided and encourages an early, aggressive approach to treating patients with ADHF.

CONCLUSIONS

Hospitalization for ADHF is common and costly. Consensus guidelines for the treatment of ADHF did not previously exist, resulting in inconsistent and inefficient treatment. Consequently, hospitals struggling with the treatment of ADHF may find these guidelines and the process by which they were developed useful. THIS ARTICLE IS APPROVED FOR CONTINUING EDUCATION CREDIT ACPE UNIVERSAL PROGRAM NUMBER: 407-000-04-015-H01

Neurohumoral stimulation in type-2-diabetes as an emerging disease concept

Neurohumoral stimulation comprising both autonomic-nervous-system dysfunction and activation of hormonal systems including the renin-angiotensin-aldosterone system (RAAS) was found to be associated with Type-2-diabetes (T2D). Therapeutic strategies such as RAAS interference proved to be beneficial in both T2D treatment and prevention. In addition to an activated RAAS, hyperleptinemia in obesity, hyperinsulinemia in conditions of peripheral insulin resistance and overall oxidative stress in T2D represent known activators of the sympathetic component of the autonomic nervous system. Here, we hypothesize that sympathetic activation may cause peripheral insulin resistance defined as partial blocking of insulin effects on glucose uptake. Resulting hyperinsulinemia or hyperglycemia-related oxidative stress may further aggravate sympatho-excitation. This notion leads to a secondary hypothesis: sympathetic activation worsens from obesity towards insulin resistance, and further towards T2D. In this review, existing evidence relating to neurohumoral stimulation in T2D and consequences thereof, such as oxidative stress and inflammation, are discussed. The aim of this review is to provide a rationale for therapies, which are able to intercept neuroendocrine pathways in T2D and precursor states such as obesity.

Predischarge B-type natriuretic peptide assay for identifying patients at high risk of re-admission after decompensated heart failure

OBJECTIVES

The aim of this study was to determine the value of serial B-type natriuretic peptide (BNP) assay for predicting post-discharge outcome of patients admitted for decompensated congestive heart failure (CHF).

BACKGROUND

Patients hospitalized for decompensated CHF are frequently re-admitted. Thus, identification of high-risk patients before their discharge is a major issue that remains challenging. B-type natriuretic peptide measurement could be useful.

METHODS

Serial BNP measurements were performed from admission to discharge in two samples of consecutive patients. Survivors were monitored for six months; the main end point combined death or first re-admission for CHF.

RESULTS

Among the 105 survivors of the derivation study, all serial BNP values, percentage change in BNP levels, and predischarge Doppler mitral pattern correlated with the outcome. In contrast, clinical variables and left ventricular ejection fraction were poorly predictive. The predischarge BNP assay had the best discriminative power (area under the receiver operating characteristic [ROC] curve = 0.80) and remained the lone significant variable in multivariate analysis (hazard ratio [HR] = 1.14 [95% confidence interval [CI], 1.02 to 1.28], p = 0.027). Among the 97 survivors of the validation study, the predischarge BNP assay was also the most predictive parameter (area under the ROC curve = 0.83). The risk of death or re-admission increased in stepwise fashion across increasing predischarge BNP ranges (p < 0.0001). After adjustment for baseline covariables, the HRs were 5.1 [95% CI 2.8 to 9.1] for BNP levels between 350 and 700 ng/l and 15.2 [95% CI 8.5 to 27] for BNP levels >700 ng/l, compared with BNP <350 ng/l.

CONCLUSIONS

High predischarge BNP assay is a strong, independent marker of death or re-admission after decompensated CHF, more relevant than common clinical or echocardiographic parameters and more relevant than changes in BNP levels during acute cares.

Natriuretic peptides as predictors of non-sudden and sudden cardiac death after acute myocardial infarction in the beta-blocking era

OBJECTIVES

This prospective study tested whether the natriuretic peptides predict cardiac death among patients using beta-blocking therapy after an acute myocardial infarction (AMI).

BACKGROUND

Natriuretic peptides have provided prognostic information after AMI, but their predictive value has not been well established in the era of beta-blocker use.

METHODS

A series of 521 patients (mean age 61 +/- 10 years) with AMI was included in the study. The end points were total mortality and non-sudden and sudden cardiac death (SCD). Plasma concentrations of atrial natriuretic peptide (ANP), N-terminal atrial natriuretic propeptide (N-ANP), brain natriuretic peptide (BNP), and ejection fraction (EF) were analyzed before hospital discharge. The cardiac medication was optimized (e.g., adherence to beta-blocking therapy was 97% at discharge and 95% at one year after AMI).

RESULTS

During a mean follow-up of 43 +/- 13 months, total mortality was 11.5% (60/521), cardiac mortality was 6.3% (33/521), and 3.1% (16/521) experienced SCD. On univariate analysis, high levels of all measured peptides and low EF predicted the occurrence of non-SCD (p < 0.001 for all). Peptides and EF also predicted the occurrence of SCD (p < 0.05), with elevated BNP (>23.0 pmol/l) being the most powerful predictor (hazard ratio [HR] 4.4, 95% confidence interval [CI] 1.4 to 13.8; p = 0.01). After adjusting for clinical variables, only elevated BNP (HR 3.9, 95% CI 1.2 to 12.3, p = 0.02) and low EF (<40%) (p = 0.03) remained as significant predictors of SCD.

CONCLUSIONS

Natriuretic peptides retain their prognostic value in the beta-blocking era among survivors of AMI. Elevated BNP provides information on the risk of subsequent SCD, independent of clinical variables and left ventricular EF.

The role and assessment of ventricular peptides in heart failure

Although heart failure may be diagnosed readily in its advanced stages, it may be difficult to diagnose clinically in its early stages.Thus, there is a critical need for an inexpensive, simple, rapid,and objective test for heart failure. This article discusses the role and assessment of ventricular natriuretic peptides and related pep-tides in heart failure.

Plasma natriuretic peptide levels and the risk of cardiovascular events and death

BACKGROUND

The natriuretic peptides are counterregulatory hormones involved in volume homeostasis and cardiovascular remodeling. The prognostic significance of plasma natriuretic peptide levels in apparently asymptomatic persons has not been established.

METHODS

We prospectively studied 3346 persons without heart failure. Using proportional-hazards regression, we examined the relations of plasma B-type natriuretic peptide and N-terminal pro-atrial natriuretic peptide to the risk of death from any cause, a first major cardiovascular event, heart failure, atrial fibrillation, stroke or transient ischemic attack, and coronary heart disease.

RESULTS

During a mean follow-up of 5.2 years, 119 participants died and 79 had a first cardiovascular event. After adjustment for cardiovascular risk factors, each increment of 1 SD in log B-type natriuretic peptide levels was associated with a 27 percent increase in the risk of death (P=0.009), a 28 percent increase in the risk of a first cardiovascular event (P=0.03), a 77 percent increase in the risk of heart failure (P<0.001), a 66 percent increase in the risk of atrial fibrillation (P<0.001), and a 53 percent increase in the risk of stroke or transient ischemic attack (P=0.002). Peptide levels were not significantly associated with the risk of coronary heart disease events. B-type natriuretic peptide values above the 80th percentile (20.0 pg per milliliter for men and 23.3 pg per milliliter for women) were associated with multivariable-adjusted hazard ratios of 1.62 for death (P=0.02), 1.76 for a first major cardiovascular event (P=0.03), 1.91 for atrial fibrillation (P=0.02), 1.99 for stroke or transient ischemic attack (P=0.02), and 3.07 for heart failure (P=0.002). Similar results were obtained for N-terminal pro-atrial natriuretic peptide.

CONCLUSIONS

In this community-based sample, plasma natriuretic peptide levels predicted the risk of death and cardiovascular events after adjustment for traditional risk factors. Excess risk was apparent at natriuretic peptide levels well below current thresholds used to diagnose heart failure.

Brain natriuretic peptide in the prediction of recurrence of angina pectoris

BACKGROUND

Circulating levels of brain natriuretic peptide (BNP) provide prognostic information for patients with heart failure, but little is known about its prognostic usefulness in patients with stable angina pectoris. We investigated whether BNP could be used as a marker for the prediction of anginal recurrence after successful treatment.

DESIGN

Brain natriuretic peptide levels of 77 patients with stable angina pectoris were measured at enrolment and after confirmation of successful treatment (i.e. no anginal attack for at least 6 months: chronic phase) with percutaneous transluminal coronary angioplasty and/or conventional medication. Then, we prospectively followed them up for 25.9 +/- 1.4 months, with the endpoint being a recurrence of anginal attacks.

RESULTS

An anginal attack recurred in seven patients. In patients without recurrence, BNP levels in the chronic phase (21 +/- 12 [median +/- median absolute deviation] pg mL-1) were lower than those measured at enrolment (46 +/- 25 pg mL-1, P < 0.0001), whereas the levels in patients with recurrence increased during the same period (from 36 +/- 16 to 72 +/- 42 pg mL-1, P < 0.05). A univariate analysis revealed that the BNP level measured in the chronic phase was the significant predictor of future anginal recurrence. Analysis of the receiver operating characteristic curve indicated that the cutoff level of BNP in the chronic phase was 68 pg mL-1. The Kaplan-Meier method revealed that the incidence of anginal recurrence was higher in patients with higher (71.4%) than lower levels of BNP (2.9%; P < 0.0001).

CONCLUSIONS

Measurement of BNP levels after successful therapy is clinically useful for the prediction of recurrence of anginal attacks in patients with angina pectoris.

Brain Natriuretic Peptide in the Management of Heart Failure

Brain natriuretic peptide (BNP), also called B-type natriuretic peptide, is a member of a family of structurally related hormones, the natriuretic peptides. Current data suggest that measurement of BNP plasma concentrations is a useful tool in the diagnosis of acute heart failure in patients presenting to an emergency department with acute dyspnea. Furthermore, BNP constitutes a promising new marker of prognosis after an acute coronary syndrome episode and in patients with chronic heart failure. Nesiritide, the human recombinant form of BNP, is a new vasodilator used in the treatment of acute heart failure that has several potential advantages over current drug therapy.

B-Type Natriuretic Peptide and Its Clinical Implications in Heart Failure

B-type natriuretic peptide (BNP) is a cardiac neurohormone released as preproBNP and then enzymatically cleaved to N-terminal-proBNP and BNP upon ventricular myocyte stretch. Blood measurements of BNP have been used to identify patients with heart failure. Currently, BNP assay is used as a diagnostic and prognostic aid in congestive heart failure. In general, a BNP level <100 pg/mL excludes acutely decompensated heart failure. This article sorts out the literature concerning the practical use of BNP in a variety of clinical scenarios.

B-Type Natriuretic Peptide: A Diagnostic, Prognostic, and Therapeutic Tool in Heart Failure

B-type natriuretic peptide is a neurohormone secreted from the cardiac ventricles in response to ventricular stretch and pressure overload. It counteracts the vasoconstriction that occurs as a compensatory mechanism in heart failure. A new test for measuring plasma levels of B-type natriuretic peptide can help in the diagnosis and treatment of patients with congestive heart failure. Dyspnea associated with cardiac dysfunction is highly unlikely in patients with levels of the peptide less than 100 pg/mL. Whereas most patients with significant congestive heart failure have levels of the peptide greater than 400 pg/mL, in patients with levels of 100 to 400 pg/mL, left ventricular dysfunction without volume overload, pulmonary embolism, and cor pulmonale must be ruled out. Thus, incorporating measurement of B-type natriuretic peptide into clinical evaluation helps physicians and nurses diagnose heart failure more quickly, especially in patients who have multiple comorbid conditions. Elevated levels of B-type natriuretic peptide indicate a poor prognosis in terms of a higher mortality and more hospital readmissions. Levels of B-type natriuretic peptide could be used to guide therapy and discharge planning for patients admitted with decompensated heart failure.

Is the Ratio of Transmitral Peak E-Wave Velocity to Color Flow Propagation Velocity Useful for Evaluating the Severity of Heart Failure in Atrial Fibrillation?

BACKGROUND

Although analysis of the transmitral inflow (TMF) pattern is widely used for evaluating left ventricular diastolic function and provides valuable information for the management of heart failure (HF) in sinus rhythm, its utility in patients with atrial fibrillation (AF) has not been established. The aim of this study was to investigate the relationship between the ratio of transmitral peak E-wave velocity to flow propagation velocity (E/Vp) obtained by a newly developed dual Doppler system and the plasma B-type natriuretic peptide (BNP) concentration or pulmonary capillary wedge pressure (PCWP) for evaluating the severity of heart failure with AF.

METHODS AND RESULTS

In 68 patients with AF, the E/Vp was compared with plasma BNP concentration and PCWP. A cutoff value of > or =1.7 for E/Vp predicted a plasma BNP concentrationl of > or =200 pg/ml, with 80% sensitivity and 84% specificity. Only E/Vp was found to be independently significant by stepwise multilinear regression analysis (r=0.40, p=0.01). PCWP values had good correlation with E/Vp (r=0.63, p<0.01) and were significantly higher in the group with E/Vp >/=1.7 (16+/-6 mmHg vs 11+/-4 mmHg, p<0.05).

CONCLUSION

The Doppler-derived index of E/Vp correlated well with the neurohormonal and hemodynamic parameters, and was useful for evaluating the severity of heart failure with AF.

Cardiac Troponin Levels in Heart Failure

Congestive heart failure (CHF) is a major cardiovascular disorder that is increasing in incidence, prevalence, and lethality. The prognostic significance of cardiac troponin levels among symptomatic and asymptomatic CHF has attracted recent interest. We sought to assess the significance of cardiac troponins in heart failure. These cardiac markers are associated with decreased left ventricular ejection fraction and poor prognosis in patients with CHF and are related to the severity of heart failure. The mechanism for the release of these markers seems to be from ventricular remodeling, ongoing myocyte degeneration, the presence of coronary artery disease, and reduced coronary reserve. In addition to B-type (brain) natriuretic peptide (BNP), cardiac troponin levels measured in patients admitted to the hospital could help risk-stratify patients and manage them effectively. BNP and cardiac troponins are easy to measure and can be repeated many times to follow patients, without interobserver variability. Theoretically, BNP is a marker of heart failure status and cardiac troponin is a marker of myocyte injury. The first therapeutic goal could be relief of circulatory congestion and lowering of BNP. The second goal could be attenuation of myocyte injury and lowering of cardiac troponins. Measuring and monitoring the levels of both could be highly effective means to reliably stratify the patients into low-, intermediate-, and high-risk groups for cardiac events and progression of heart failure. Furthermore, large-scale trials are necessary to establish them as noninvasive monitoring markers of heart failure and effectiveness of treatment.