Evaluation of B-type natriuretic peptide for risk assessment in unstable angina/non-ST-elevation myocardial infarction: B-type natriuretic peptide and prognosis in TACTICS-TIMI 18

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

BACKGROUND

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

HYPOTHESIS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Risk stratification and prognostic factors in the post-myocardial infarction patient

Among the 5 million patients presenting to emergency departments with chest pain each year in the United States, approximately 1 million are diagnosed with myocardial infarction (MI). Physicians have the difficult task of making decisions regarding admission and treatment and identifying patients at high risk for adverse outcomes, such as early mortality, left ventricular dysfunction (LVD), and heart failure. Several measures can be implemented in the process of risk assessment, including clinical judgment, electrocardiographic and echocardiographic findings, and the presence of biomarkers. Biomarkers--which can be classified as antecedent, screening, diagnostic, staging, or prognostic--may help identify the subset of patients who need early intervention and/or intensive therapy. Using a multimarker strategy that combines a marker of hemodynamic stress (brain natriuretic peptide) or of inflammation (C-reactive protein) with a marker of necrosis (cardiac troponin) may help to risk-stratify patients, guide treatment, and optimize admission and discharge decisions. This article discusses the potential benefits of risk assessment tools in the management of post-MI patients with LVD.

Brain natriuretic peptides as biomarkers for atherosclerosis

Identification of atherosclerotic risk factors provides targets for development of preventive therapies. Risk factor assessment permits evaluation of an individual's prospective risk of coronary heart disease (CHD). However, it has become apparent that traditional risk factors may not predict CHD in some patients. As a result, many individuals do not receive the benefit of intensive preventive strategies. Accordingly, considerable effort has focused on the identification of novel biomarkers to enhance risk stratification. Given its prognostic utility in heart failure and acute coronary syndrome, brain natriuretic peptide (BNP) and its amino-terminal fragment have received interest as possible biomarkers for CHD.

Preoperative B-type natriuretic peptide is as independent predictor of ventricular dysfunction and mortality after primary coronary artery bypass grafting

OBJECTIVE

Elevated B-type natriuretic peptide is associated with increased morbidity and mortality in ambulatory patients with congestive heart failure or acute coronary syndromes. Its utility in predicting adverse cardiac surgical outcomes is less certain. We hypothesized that preoperative plasma B-type natriuretic peptide would independently predict in-hospital postoperative ventricular dysfunction, hospital stay, and up to 5-year mortality after primary coronary artery bypass grafting.

METHODS

This is a prospective, longitudinal study of 1023 patients at two institutions undergoing primary coronary artery bypass grafting with cardiopulmonary bypass. Ventricular dysfunction was defined as requirement for at least two inotropes or new intra-aortic balloon pump or ventricular assist device support after coronary artery bypass grafting. Multivariable analyses assessed independent roles of preoperative B-type natriuretic peptide in predicting postoperative ventricular dysfunction, hospital stay, and 5-year all-cause mortality.

RESULTS

Preoperative plasma B-type natriuretic peptide concentration predicted ventricular dysfunction, hospital stay, and mortality in univariate and multivariable analyses. Logistic regression demonstrated preoperative B-type natriuretic peptide to independently predict ventricular dysfunction (odds ratio 1.92, 95% confidence interval 1.12-3.29, P = .018), after adjustment for preoperative left ventricular ejection fraction, congestive heart failure severity, and other clinical predictors. Multivariable Cox proportional hazards models showed preoperative B-type natriuretic peptide to independently predict hospital stay (hazard ratio 1.42, 95% confidence interval 1.18-1.72, P = .0002) and mortality (hazard ratio 1.89, 95% confidence interval 1.08-3.33, P = .026).

CONCLUSION

Preoperative plasma B-type natriuretic peptide independently predicted in-hospital ventricular dysfunction, hospital stay, and up to 5-year all-cause mortality after primary coronary artery bypass grafting.

Thrombus precursor protein and clinical outcomes in patients with acute coronary syndromes

OBJECTIVES

We sought to test the prognostic performance of thrombus precursor protein (TpP) in patients presenting with an acute coronary syndrome (ACS).

BACKGROUND

Because thrombus formation is a critical step in the development of ACS, a measurement of activated coagulation could yield important information. Thrombus precursor protein is a biomarker that is used to measure soluble fibrin polymers, which are the penultimate products in fibrin formation.

METHODS

We measured the levels of TpP in 284 healthy volunteers and in 2,349 patients with ACS.

RESULTS

Median TpP concentrations were 3.6 mug/ml (interquartile range 2.6 to 5.5) in the volunteers and 8.9 mug/ml (interquartile range 4.9 to 15.9) in the ACS patients (p < 0.001). Patients with ACS who had elevated TpP were older, more likely to be women, and more likely to have diabetes and pre-existing CAD (p < 0.02 for each). Thrombus precursor protein levels greater than the median were associated with a significantly increased risk for the composite of death, myocardial infarction (MI), or recurrent ischemia leading to rehospitalization or urgent revascularization through 10 months (hazard ratio [HR] 1.45, p < 0.001), as well as death or MI (HR 1.42, p = 0.02). We found that TpP correlated only weakly with cardiac troponin I, B-type natriuretic peptide, and high-sensitivity C-reactive protein (|r| <0.15 for each). After adjusting for clinical characteristics, cardiac troponin I, high-sensitivity C-reactive protein, and B-type natriuretic peptide, we found that patients with TpP levels greater than the median remained at significantly increased risk for the composite outcome (adjusted HR 1.51, p = 0.001) and death or MI (adjusted HR 1.58, p = 0.02).

CONCLUSIONS

In patients with ACS, increased levels of TpP are associated with an increased risk of death or ischemic complications. The incorporation of a marker of activated coagulation, such as TpP, with established cardiovascular risk factors may offer valuable complementary insight into risk assessment in ACS.

Defining a role for novel biomarkers in acute coronary syndromes

BACKGROUND

Biomarkers play a pivotal role in the diagnosis and treatment of patients with cardiovascular disease. Active investigation has brought forward an increasingly large number of novel candidate markers; however, few of these markers have yet to be incorporated into routine clinical use.

CONTENT

This review discusses biomarkers currently used in the setting of acute coronary syndromes. In this context, we assess the contemporary unmet needs for novel biomarkers in acute ischemic heart disease and the related challenges faced in developing new biomarkers to the point of integration into clinical practice. In particular, we address the impact of the availability of increasingly sensitive biomarkers of myocardial necrosis on the potential roles for novel biomarkers of inflammation, thrombosis, and ischemia.

SUMMARY

Although active investigation has produced a growing list of candidate novel biomarkers for the care of patients with cardiovascular disease, it has become increasingly challenging to find appreciable incremental clinical benefit for their addition to existing markers, in particular newer, more analytically sensitive cardiac troponin assays. A major challenge for researchers and clinicians will be to demonstrate whether candidate novel markers are useful in improving diagnosis and guiding clinical treatment.

Concurrent evaluation of novel cardiac biomarkers in acute coronary syndrome: myeloperoxidase and soluble CD40 ligand and the risk of recurrent ischaemic events in TACTICS-TIMI 18

AIMS

We investigated the prognostic performance of myeloperoxidase (MPO), and soluble CD40 ligand (sCD40L) along with B-type natriuretic peptide (BNP), high-sensitivity C-reactive protein (hsCRP), and cardiac troponin I (cTnI) for non-fatal recurrent ischaemic events in non-ST elevation acute coronary syndrome (ACS).

METHODS AND RESULTS

We measured plasma MPO and sCD40L in 1524 patients with ACS treated with tirofiban and randomized to early invasive vs. conservative management in the TACTICS-TIMI 18 trial who survived to 180 days. Patients with elevated baseline MPO (>884 pM) were at higher risk of non-fatal myocardial infarction or rehospitalization for ACS at 30 days (9.3 vs. 4.6%, P < 0.001). In contrast, no difference was observed with higher sCD40L (>989 pg/mL, 7.6 vs. 6.3%, P = 0.31). MPO remained associated with recurrent ischaemic events after adjustment for age, ST-deviation, diabetes, prior coronary artery disease, heart failure, cTnI, hsCRP, and sCD40L (OR 2.10; 95% CI 1.36-3.23, P = 0.001). This association was attenuated by 180 days (OR 1.26; 0.95-1.68). Stratification using baseline MPO, BNP, and cTnI identified a >3-fold gradient of risk.

CONCLUSION

MPO adds to BNP and cTnI for short-term risk assessment for recurrent ischaemic events in non-ST elevation ACS. sCD40L was not associated with risk in this population treated with a platelet GPIIb/IIIa receptor antagonist.

Amino-terminal pro-B-type natriuretic peptides in stable and unstable ischemic heart disease

Across the entire spectrum of ischemic heart disease, amino-terminal pro-B-type natriuretic peptides (NT-proBNP) are a strong and independent prognostic indicator, representing a particularly strong predictor of heart failure or death. This risk is independent of all other variables, including renal function or troponin, and is proportional to the magnitude of NT-proBNP release, with higher risk observed among those with a more marked elevation of the marker. Although prospective studies on the effect of NT-proBNP measurement in guiding therapy in ischemic heart disease are lacking, among patients presenting with acute coronary syndromes, it is recommended to measure NT-proBNP on (or near) the time of admission. An elevated initial NT-proBNP concentration should prompt consideration of an early invasive management approach. Consideration should be given to repeating the NT-proBNP measurement after 24-72 hours and again at 3-6 months because these follow-up measurements provide more long-term prognostic information than single measures at presentation. In acute ischemic heart disease, an NT-proBNP value >250 ng/L is associated with an adverse prognosis. In patients with stable coronary artery disease, measurement may be performed for prognostication purposes at 6- to 18-month intervals. In the case of clinical suspicion of disease progression, a new sample may be warranted.

The Potential of Cardiac Markers to Improve Patient Management

B-type natriuretic peptide (BNP) is a quantitative marker for heart failure. The use of BNP in patients with dyspnea has consistently shown to improve patient management and reduce treatment cost. Additional indications with the potential to improve patient management include treatment monitoring in acute and chronic heart failure, pulmonary embolism, and coronary artery disease.

Patterns and implications of B-type natriuretic peptide measurement in patients with non-ST-segment elevation acute coronary syndromes

Elevated B-type natriuretic peptide (BNP) levels are associated with increased risk for mortality in patients with non-ST-segment-elevation (NSTE) acute coronary syndromes (ACS). However, the optimal use of BNP measurement for the risk stratification of these patients remains unclear. This study was conducted to analyze patterns of, and factors associated with, BNP measurement in patients with NSTE ACS from the Can Rapid Risk Stratification of Unstable Angina Patients Suppress Adverse Outcomes With Early Implementation of the American College of Cardiology/American Heart Association Guidelines? (CRUSADE) quality improvement initiative from 2003 through 2006. The association of degree of BNP elevation with in-hospital mortality in patients with measured BNP levels across risk categories was also analyzed. A total of 16,323 of 77,071 patients (21.2%) from 486 hospitals had BNP levels measured; the rate of BNP measurement by quarter increased from 5.1% to 27.7% during this analysis. Factors most strongly associated with BNP measurement included signs of heart failure on presentation, older age, previous heart failure, faster presenting heart rate, and higher body mass index. The adjusted risk for mortality was higher in patients who had BNP levels measured than in those who did not (adjusted odds ratio 1.14, 95% confidence interval 1.03 to 1.25). In patients with BNP levels measured, a higher degree of BNP elevation was associated with incrementally higher in-hospital mortality rates across risk categories. BNP levels were measured in approximately 1/5 of patients with NSTE ACS in contemporary practice. BNP was most frequently measured in patients presenting with high-risk characteristics, but the association of incremental increases in BNP levels with higher mortality rates was similar across risk categories. In conclusion, more widespread measurement of BNP levels for risk stratification of patients with NSTE ACS may be warranted.

N-terminal pro-B-type natriuretic peptide is an independent predictor of outcome in an unselected cohort of critically ill patients*

OBJECTIVES

Natriuretic peptides emerged during recent years as potent prognostic markers in patients with heart failure and acute myocardial infarction. In addition, natriuretic peptides show strong predictive value in patients with pulmonary embolism, sepsis, renal failure, and shock. The present study tests the prognostic information of N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) in an unselected cohort of critically ill patients.

DESIGN

Prospective, observational study.

SETTING

A tertiary intensive care unit in a university hospital.

PATIENTS

A total of 289 consecutive patients admitted to the intensive care unit during a 16-month period with the following data: age 64 +/- 14 yrs, male n = 191, Simplified Acute Physiology Score II of 52 +/- 24, mechanical ventilation n = 180 (62%), vasopressors n = 179 (62%), renal failure n = 24 (8%).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Plasma NT-pro-BNP samples (Roche Diagnostics) were obtained on intensive care unit admission. Data are given as median [range]. Intensive care unit survivors had significantly lower NT-pro-BNP values compared with intensive care unit nonsurvivors (3394 [24-35,000] vs. 6776 [303-35,000] pg/mL, survivors vs. nonsurvivors, respectively, p = .001). Hospital survivors were characterized by significantly lower NT-pro-BNP values (2656 [24-35,000] vs. 8390 [303-35,000] pg/mL, survivors vs. nonsurvivors, respectively, p = .001). NT-pro-BNP levels were not significantly different in patients with primary cardiac diagnosis compared with those with a noncardiac admission diagnosis (4794 [26-35,000], n = 202 vs. 3349 [24-35,000], n = 87, cardiac vs. noncardiac, respectively, p = .28). In a logistic regression model, Simplified Acute Physiology Score II and NT-pro-BNP were independently associated with hospital survival (chi = 35.6, p = .0001 and chi = 11.3, p = .0008, Simplified Acute Physiology Score II and NT-pro-BNP, respectively). Areas under the receiver operating characteristic curves of NT-pro-BNP and Simplified Acute Physiology Score II were not statistically significant different regarding the prediction of outcome.

CONCLUSIONS

NT-pro-BNP on admission is an independent prognostic marker of outcome in an unselected cohort of critically ill patients. A single measurement of NT-pro-BNP might facilitate triage of emergency and intensive care unit patients.

A systematic review of BNP as a predictor of prognosis in persons with coronary artery disease

OBJECTIVE

This systematic review was conducted to examine whether B-type natriuretic peptide (BNP) can predict mortality and other cardiac endpoints in persons diagnosed with coronary artery disease (CAD).

DESIGN AND METHODS

Databases were searched from 1989 to February 2005 for primary studies that measured BNP for the purpose of diagnosis, prognosis, and monitoring treatment.

RESULTS

In 18 studies, concentrations of BNP were found to have consistent positive associations with poorer prognoses for persons with CAD. The overall range of effect (95% confidence interval) was 2.31 to 5.02, measured via a random effects meta-analysis on studies reporting an odds ratio. Prognostic ability was similar for mortality and non-fatal outcomes. Ranges of estimated measures of effect (i.e., odds ratio, relative risk, hazard ratio) were concentrated between 1.33 to 2.94 for mortality and 1.01 to 3.03 for non-fatal outcomes.

CONCLUSIONS

Further research is needed to assess whether prognostic ability differs by comorbidity or concomitant treatment. As well, the importance and selection of cut points remains unresolved. Until greater clarity is given to these matters, it would be prudent for clinicians to employ caution when using concentrations of BNP to predict the prognosis of persons with CAD.

Prognostic significance of the admission plasma B-type natriuretic peptide measurement in patients with first ST-elevation myocardial infarction in comparison with C-reactive protein and TIMI risk score

BACKGROUND

In ST-elevation myocardial infarction (STEMI) B-type natriuretic peptide (BNP) holds promise for risk stratification. Aim of this study was to assess prognostic value of plasma BNP measurement and to compare with other powerful prognostic markers -- TIMI Risk Score (TRS) and C-reactive protein (CRP) in patients with first STEMI treated with primary PCI (pPCI).

METHODS

86 patients, admitted within initial 12 h of the first STEMI. Admission plasma levels of BNP were measured by MEIA method. Serum levels of CRP were measured using immunoturbidimetric assays. Composite end point (CEP) was assessed after 7 months.

RESULTS

Median plasma BNP value was higher in patients with CEP, compared with those without CEP (p<0.001). Patients with plasma BNP >99.2 pg/mL were at significantly higher risk for CEP (the highest sensitivity and specificity). CRP level >10.6 mg/dL was also associated with poor outcome. TRS has not influenced the occurrence of CEP. In the analysis of logistic regression the BNP value >99.2 pg/mL was the strongest predictor of CEP. ROC analysis identified BNP measurement as significant to estimate adverse outcome 0.950 in the prediction of CEP (95% Confidence interval=0.878-0.985).

CONCLUSION

Admission plasma BNP concentrations provide incremental prognostic information in patients with first STEMI treated with pPCI.

Lipoprotein-associated phospholipase A2 for early risk stratification in patients with suspected acute coronary syndrome: a multi-marker approach: the North Wuerttemberg and Berlin Infarction Study-II (NOBIS-II)

AIMS

Numerous markers have been identified as useful predictors of major adverse cardiac events (MACE) in patients with suspected acute coronary syndrome (ACS). However, only little is known about the relative benefit of the single markers in risk stratification and the best combination for optimising prognostic power. The aim of the present study was to define the role of the emerging cardiovascular risk marker lipoprotein-associated phospholipase A2 (Lp-PLA2) in a multi-marker approach in combination with troponin I (TnI), NT-proBNP, high sensitivity (hs)CRP, and D-dimer in patients with ACS.

METHODS AND RESULTS

A total of 429 consecutive patients (age 60.5+/-14.1 years, 60.6% male) who were admitted to the emergency room with suspected ACS were analysed in the study. Biochemical markers were measured by immunoassay techniques. All patients underwent point-of-care TnI testing and early coronary angiography if appropriate, in accordance with the current guidelines. Classification and regression trees (CART) and logistic regression techniques were employed to determine the relative predictive power of markers for the primary end-point defined as any of the following events within 42 days after admission: death, non-fatal myocardial infarction, unstable AP requiring admission, admission for decompensated heart failure or shock, percutaneous coronary intervention, coronary artery bypass grafting, life threatening arrhythmias or resuscitation. The incidence of the primary end-point was 13.1%, suggesting a mild to moderate risk population. The best overall risk stratification was obtained using NT-proBNP at a cut-off of 5000 pg/mL (incidence of 40% versus 10.3%, relative risk (RR) 3.9 (95% CI 2.4-6.3)). In the remaining lower risk group with an incidence of 10.3%, further separation was performed using TnI (cut-off 0.14 microg/L; RR=3.1 (95% CI 1.7-5.5) 23.2% versus 7.5%) and again NT-proBNP (at a cut-off of 140 ng/L) in patients with negative TnI (RR=3.2 (95% CI 1.3-7.9), 11.7% versus 3.6%). A final significant stratification in patients with moderately elevated NT-proBNP levels was achieved using Lp-PLA2 at a cut-off of 210 microg/L) (17.9% versus 6.9%; RR=2.6 (95% CI 1.1-6.6)). None of the clinical or ECG variables of the TIMI (Thrombolysis In Myocardial Infarction) risk score provided comparable clinically relevant information for risk stratification.

CONCLUSIONS

In the setting of stateof- the-art coronary care for patients with suspected ACS in the emergency room, NT-proBNP, troponin I, and Lp-PLA2 are effective independent markers for risk stratification that proved to be superior to the TIMI risk score. Lp-PLA2 turned out to be a more effective risk marker than hsCRP in these patients.

The value of bedside cardiac multibiomarker assay in rapid and accurate diagnosis of acute coronary syndromes

For emergency department physicians, timely triage and risk stratification of chest pain patients remains a challenge. Faced with an aging population and the growing prevalence of heart disease, clinicians are seeking more effective ways to diagnose acute coronary syndromes rapidly and accurately. Emergency department physicians must make critical and time-sensitive decisions based on patient history, physical examination, and 12-lead electrocardiogram as justification for diagnosis of acute coronary syndromes. But because most of these tools are not reliable independently, these incomplete strategies can result in costly and inappropriate treatment decisions.

Cardioprotective actions of peptide hormones in myocardial ischemia

The myocardium represents a major source of several families of peptide hormones under normal physiological conditions and the plasma concentrations of many of these "cardiac peptides" (or related pro-peptide fragments) are substantially augmented in many cardiac disease states. In addition to well-characterised endocrine functions of several of the cardiac peptides, pleiotropic functions within the myocardium and the coronary vasculature represent a significant aspect of their actions in health and disease. Here, we focus specifically on the cardioprotective roles of four major peptide families in myocardial ischemia and reperfusion: adrenomedullin, kinins, natriuretic peptides and the urocortins. The patterns of early release of all these peptides are consistent with roles as autacoid cardioprotective mediators. Clinical and experimental research indicates the early release and upregulation of many of these peptides by acute ischemia and there is a convincing body of evidence showing that exogenously administered adrenomedullin, bradykinin, ANP, BNP, CNP and urocortins are all markedly protective against experimental myocardial ischemia-reperfusion injury through a conserved series of cytoprotective signal transduction pathways. Intriguingly, all the peptides examined so far have the potential to salvage against infarction when administered specifically during early reperfusion. Thus, the myocardial secretion of peptide hormones likely represents an early protective response to ischemia. Further work is required to explore the potential therapeutic manipulation of these peptides in acute coronary syndromes and their promise as biomarkers of acute myocardial ischemia.

B-type natriuretic peptide: a critical review

Natriuretic peptides have been used as tools for diagnosis and risk stratification in patients with heart failure, myocardial infarction, and unstable coronary syndromes, as well as in the general population. The biology of intra-assay and intraindividual variations of plasma natriuretic peptide levels is still not clearly understood despite their broad adoption in clinical practice. Interpretation of plasma natriuretic peptide levels therefore requires availability of the clinical context as well as considerations of various confounders. It is clear that high plasma natriuretic peptide levels can be highly suggestive of underlying myocardial disease, although a specific underlying cause cannot be identified based on the test results. The potential use of natriuretic peptide levels to monitor and guide patient management or detect subclinical disease states is currently under investigation.

N-terminal pro-brain natriuretic peptide for additional risk stratification in patients with non-ST-elevation acute coronary syndrome and an elevated troponin T: an Invasive versus Conservative Treatment in Unstable coronary Syndromes (ICTUS) substudy

BACKGROUND

New evidence has emerged that the assessment of multiple biomarkers such as cardiac troponin T (cTnT) and N-terminal pro-brain natriuretic peptide (NT-proBNP) in patients with non-ST-elevation acute coronary syndrome (nSTE-ACS) provides unique prognostic information. The purpose of this study was to assess the association between baseline NT-proBNP levels and outcome in patients who have nSTE-ACS with an elevated cTnT and to determine whether patients with elevated NT-proBNP levels benefit from an early invasive treatment strategy.

METHODS

Baseline samples for NT-proBNP measurements were available in 1141 patients who have nSTE-ACS with an elevated cTnT randomized to an early or a selective invasive strategy. Patients were followed-up for the occurrence of death, myocardial infarction (MI), and rehospitalization for angina.

RESULTS

We showed that increased levels of NT-proBNP were associated with several indicators of risk and severe coronary artery disease. Mortality by 1 year was 7.3% in the highest quartile (> or = 1170 ng/L for men, > or = 2150 ng/L for women) compared with 1.1% of patients in the lower 3 quartiles (P < .0001). N-terminal pro-brain natriuretic peptide (highest quartile vs lower 3 quartiles) was a strong independent predictor of mortality (hazard ratio 5.0, 95% CI 2.1-11.6, P = .0002). However, NT-proBNP levels were not associated with the incidence of recurrent MI by 1 year. Furthermore, we could not demonstrate a benefit of an early invasive strategy compared with a selective invasive strategy in patients with an elevated NT-proBNP level.

CONCLUSIONS

We confirmed that NT-proBNP is a strong independent predictor of mortality by 1 year but not of recurrent MI in patients who have nSTE-ACS with an elevated cTnT. We could not demonstrate a benefit of an early invasive strategy compared with a selective invasive strategy.

Diagnostic accuracy of serum B-type natriuretic peptide for myocardial ischemia detection during exercise testing with Spect perfusion imaging

OBJECTIVE

To determine whether serum B-type natriuretic peptide measured at rest and peak exercise and DeltaBNP contribute to the predictive value and diagnostic accuracy of exercise test in the diagnosis of myocardial ischemia.

BACKGROUND

Ventricular myocytes release BNP in response to increased wall stress that occurs in acute ischemia. During exercise testing, transient myocardial ischemia could also cause acute myocardial stress and changes in circulating BNP.

METHODS

BNP was measured before and immediately after exercise testing with radionuclide imaging in 203 consecutive subjects referred for chest pain evaluation. Tested subjects were classified as ischemic and non-ischemic based on exercise results, and no ischemia, mild-moderate, and severe ischemia according to perfusion scan results. A logistic regression model, constructed of an ROC and an AUC (area under the curve), was used.

RESULTS

Ischemic ECG changes (> or =1 mm, horizontal S-T shift) were detected in the treadmill exercise test in 127 subjects (62.6%), and 76 (37.4%) had neither ST segment shift nor chest pain. Baseline BNP was higher in the ischemic group compared to the non-ischemic group (p=0.044); peak BNP was also higher in the ischemic group (p=0.025), as was DeltaBNP (p=0.0126). Of these 127 subjects, 106 (52% of all) had abnormal perfusion scan results. In the ischemic group, the median baseline, peak exercise BNP, and DeltaBNP values from baseline to peak were higher than in the non-ischemic group. In the severe ischemic group these variables were approximately three-fold higher than in the mild-moderate ischemic group (p<0.0001 for baseline; p<0.0001 for peak; and p<0.0001 for DeltaBNP). Rest, peak exercise, and DeltaBNP values were significantly higher in patients with previous myocardial infarction (p<0.001) and in patients treated with beta blockers; peak exercise BNP was higher in hypertensives and diabetics (p<0.05). The ROC convergence model showed that the AUC for peak-exercise BNP was best able to discriminate and predict severe ischemia and no ischemia, while DeltaBNP from rest to peak exercise discriminated best between mild-moderate and severe ischemia.

CONCLUSIONS

Peak exercise BNP and DeltaBNP improved the sensitivity, specificity, positive likelihood ratio, predictive value, and diagnostic accuracy of severe ischemia detection during an exercise test. The contribution of BNP determination during exercise was, however, less impressive than previously reported by others.

B-type natriuretic peptide release in the coronary effluent after acute transient ischaemia in humans

BACKGROUND

The association between B-type natriuretic peptide (BNP) and coronary artery disease is not fully understood.

OBJECTIVE

To assess whether ischaemia per se is a stimulus for BNP secretion.

SETTING

University tertiary hospital, Spain (Virgen de la Arrixaca).

DESIGN

Prospective interventional study.

PATIENTS

11 patients (55 (9) years, left ventricular ejection fraction (LVEF) 45% (7%) with a non-complicated anterior myocardial infarction (MI) and isolated stenosis of the left anterior descending (LAD) coronary artery, successfully treated by primary angioplasty.

INTERVENTIONS

11.0 (0.9) days after MI, the LAD was occluded (20 min) for intracoronary infusion of progenitor cells. Blood samples were obtained from the femoral artery (peripheral circulation (PC)) and the coronary sinus (coronary circulation (CC)) immediately before and after coronary occlusion.

MAIN OUTCOME MEASURES

BNP (pg/ml) was measured and ischaemia biomarkers were monitored.

RESULTS

During coronary occlusion, all patients experienced transitory chest pain and ST-segment dynamic changes. After coronary occlusion, lactic acid levels rose in CC (1.42 (0.63) -1.78 (0.68) ng/ml, p = 0.003). Myoglobin and cardiac troponin T did not differ in CC or PC at 24 h. No differences were found in LVEF (+0.18% (2.4)%, p = 0.86) and motion score index (-0.02 (0.06), p = 0.37). Before occlusion, BNP levels did not differ significantly in CC versus PC (253 (56) vs 179 (34), p = 0.093). After occlusion, BNP showed a significant increase in CC (vs 332 (61), p = 0.004), but no change occurred in PC (vs 177 (23), p = 0.93), and circulating BNP levels were higher in CC versus PC (p = 0.008).

CONCLUSIONS

In response to acute ischaemia, BNP levels immediately increase in coronary sinus but not at the peripheral level. BNP release in the coronary effluent may exert local beneficial effects.

Interpretation of B-type natriuretic peptide in cardiac disease and other comorbid conditions

B-Type natriuretic peptide (BNP) is elevated in states of increased ventricular wall stress. BNP is most commonly used to rule out congestive heart failure (CHF) in dyspneic patients. BNP levels are influenced by age, gender and, to a surprisingly large extent, by body mass index (BMI). In addition, it can be elevated in a wide variety of clinical settings with or without CHF. BNP is elevated in other cardiac disease states such as the acute coronary syndromes, diastolic dysfunction, atrial fibrillation (AF), amyloidosis, restrictive cardiomyopathy (RCM), and valvular heart disease. BNP is elevated in non-cardiac diseases such as pulmonary hypertension, chronic obstructive pulmonary disease, pulmonary embolism, and renal failure. BNP is also elevated in the setting of critical illness such as in acute decompensated CHF (ADHF) and sepsis. This variation across clinical settings has significant implications given the increasing frequency with which BNP testing is being performed. It is important for clinicians to understand how to appropriately interpret BNP in light of the comorbidities of individual patients to maximize its clinical utility. We will review the molecular biology and physiology of natriuretic peptides as well as the relevant literature on the utilization of BNP in CHF as well as in other important clinical situations, conditions that are commonly associated with CHF and or dyspnea.

Kardiale Labordiagnostik – State-of-the-Art 2007

Biomarkers have gained increasing significance in clinical cardiology during the last two decades. Laboratory parameters play an important role as risk markers for coronary events in primary and secondary prevention, in the diagnosis of acute myocardial necrosis and heart failure as well as in the management of patients with heart valve diseases. The development of novel biochemical markers has also led to new insights in the pathophysiology of coronary artery disease, acute coronary syndromes and heart failure. This review summarizes the state of the art of cardiac biomarkers suitable for routine use.

The Impact of B-Type Natriuretic Peptide in Addition to Troponin I, Creatine Kinase-MB, and Myoglobin on the Risk Stratification of Emergency Department Chest Pain Patients With Potential Acute Coronary Syndrome

STUDY OBJECTIVE

The emergency department (ED) evaluation of chest pain patients with potential acute coronary syndrome is limited by the initial sensitivity of cell injury markers. BNP is increased during myocardial ischemia and is associated with adverse outcomes. We determine whether the addition of B-type natriuretic peptide (BNP) to troponin I, creatine kinase-MB (CK-MB), and myoglobin increases the sensitivity and negative predictive value (NPV) for acute myocardial infarction, acute coronary syndrome, and 30-day adverse events among chest pain patients with potential acute coronary syndrome.

METHODS

A convenience sample of patients aged 30 years or older and presenting to an urban academic ED with nontraumatic chest pain, thus prompting an ECG, was enrolled, and consent was obtained. Blood samples were drawn at 0 and 90 minutes. Thirty-day follow-up was performed for all enrolled patients. Main outcomes were acute myocardial infarction, acute coronary syndrome, and 30-day events (death, acute myocardial infarction, or revascularization). BNP cutoffs were derived from receiver operator characteristics curves. The sensitivity, specificity, positive predictive value (PPV), and NPV with 95% confidence intervals (CIs) were calculated with and without BNP. Differences in sensitivity and specificity with the addition of BNP were calculated with 95% CIs, and McNemar's test was performed to compare sensitivities and specificities.

RESULTS

Four hundred twenty-six patients were enrolled and analyzed. The cohort was 54.7+/-13.9 years old, 47.7% men, and 63.5% black. The outcomes were acute myocardial infarction, 39 (9.2%), acute coronary syndrome, 101 (23.7%), and 30-day adverse cardiovascular events 52 (12.2%). BNP cutoffs derived were 51, 31, and 31 pg/mL for acute myocardial infarction, acute coronary syndrome, and 30-day events, respectively. The addition of BNP showed increased sensitivity at the cost of decreased specificity for all 3 outcomes, as follows: (1) acute myocardial infarction: sensitivity: 87.2% (95% CI 72.6% to 95.7%) to 97.4% (95% CI 86.5% to 100%), difference 10.3% (95% CI-0.2% to 24.6%), P=.125; specificity: 62.3% (95% CI 57.2% to 67.1%) to 47.8% (95% CI 42.7% to 52.9%), difference 14.5% (95% CI 11.1% to %18.4), P<.0001; (2) acute coronary syndrome: sensitivity: 75.2% (95% CI 65.7% to 83.3%) to 88.1% (95% CI 80.2% to 93.7%), difference 12.9% (95% CI 7.0% to 21.0%), P=.0002; specificity: 68.0% (95% CI 62.6% to 73.0%) to 48.6% (95% CI 43.1% to 54.2%), difference 19.4% (95% CI 15.2% to 24.1%), P<.0001; (3) 30-day events: sensitivity: 71.2% (95% CI 56.9% to 82.9%) to 88.5% (95% CI 76.6% to 95.7%), difference 17.3% (95% CI 7.7% to 30.3%), P=.004; specificity: 61.8% (95% CI 56.6% to 66.7%) to 43.9% (95% CI 38.8% to 49.0%), difference 17.9% (95% CI 14.2% to 22.2%), P<.0001. There were trends toward increased NPV and decreased PPV for all outcomes, and the addition of BNP achieved a NPV of 99.5% (95% CI 97.0% to 100%) compared with 98.0% (95% CI 95.3% to 99.3%) for acute myocardial infarction.

CONCLUSION

The addition of BNP as a dichotomous test to troponin I, CK-MB, and myoglobin produces increased sensitivity at a cost of decreased specificity for acute myocardial infarction, acute coronary syndrome, and 30-day adverse events. Because of this tradeoff, BNP cannot be recommended for use among all ED chest pain patients. However, the improved sensitivity may make this test useful in selected cohorts when the decreased specificity is less important.

Hemodynamic significance of periprocedural myocardial injury assessed with N-terminal pro-B-type natriuretic peptide after percutaneous coronary intervention in patients with stable and unstable coronary artery disease (from the JUMBO-TIMI 26 trial)

The clinical relevance of periprocedural myocardial injury related to percutaneous coronary intervention (PCI) remains controversial. N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) is a sensitive indicator of hemodynamic stress and when increased is associated with higher mortality in patients with acute and chronic ischemic heart disease. We measured the serum level of NT-pro-BNP using the Elecsys 2010 proBNP assay at baseline, 4 to 6 hours, and 12 to 24 hours in 747 patients undergoing elective or urgent PCI and enrolled in the JUMBO-TIMI 26 trial. Periprocedural myocardial infarction (MI) was independently adjudicated and required a new increase in creatine kinase-MB >3 times the upper limit of normal distinct from MI as the indication for PCI. Patients with procedural MI had significantly higher levels of NT-pro-BNP at 12 to 24 hours (405 vs 146 pg/ml, p <0.001). Moreover, the greater increase in NT-pro-BNP in patients with periprocedural MI was independent of each clinical and other procedural correlates of NT-pro-BNP after PCI (p <0.001). In addition, the magnitude of increase in NT-pro-BNP correlated strongly with extent of myocardial injury, including in patients with evidence of injury (creatine kinase-MB 1 to 3 times upper limit of normal) not meeting criteria for MI (p = 0.001) or low-level increase in troponin T (p = 0.001). In conclusion, periprocedural myocardial injury, even at low levels, during PCI is associated with increased hemodynamic stress as measured by increasing NT-pro-BNP. This finding supports the physiologic relevance of procedural MI and the continued effort to define therapies that decrease the risk of this complication.

Admission B-type natriuretic peptide assessment improves early risk stratification by Killip classes and TIMI risk score in patients with acute ST elevation myocardial infarction treated with primary angioplasty

BACKGROUND

TIMI risk score for ST elevation acute myocardial infarction (STEMI) and Killip classes are simple tools for early risk stratification.

AIM

This study aims to evaluate the hypothesis that admission of BNP adds prognostic information to Killip classes and TIMI risk score in patients with STEMI treated with primary percutaneous coronary intervention (PCI).

METHODS

BNP concentrations in blood samples obtained on admission in 126 consecutive patients (mean age 58.8+/-10.7 years old) with STEMI were assessed with means of point-of-care test before PCI. A 42-day follow-up for total mortality was performed.

RESULTS

BNP levels increased significantly with increasing Killip classes and TIMI risk score. Addition of BNP to Killip classes and to TIMI risk score increased area under the ROC from 0.704 to 0.887 and from 0.852 to 0.918, respectively. There was a significant increase in mortality in the subgroups by Killip classes and BNP: 1.1% for Killip I and BNP < 331 mg/ml; 16% for Killip I or BNP > or = 331 mg/ml; 55.6% for Killip I and BNP > or = 331 mg/ml; p<0.0001; and in subgroups by TIMI risk score and BNP: 0% for TIMI risk score < 4 and BNP < 331 pg/ml; 2.8% for TIMI risk score > or = 4 and BNP < 331 pg/ml; 12.5% for TIMI risk score < 4 and BNP > or = 331 pg/ml; and 50% for TIMI risk score > or = 4 and BNP > or = 331 pg/ml; (p<0.0001). In multivariate model BNP was a prognostic variable for mortality, independent from TIMI risk score.

CONCLUSIONS

Admission of BNP adds significant prognostic information beyond that of Killip classes and TIMI risk score in patients with STEMI treated with PCI.

N-terminal fragment of the prohormone brain-type natriuretic peptide (NT-proBNP), cardiovascular events, and mortality in patients with stable coronary heart disease

CONTEXT

Identification of individuals at high risk for cardiovascular events is important for the optimal use of primary and secondary prevention measures.

OBJECTIVE

To determine whether plasma levels of amino terminal fragment of the prohormone brain-type natriuretic peptide (NT-proBNP) predict cardiovascular events or death independent of other available prognostic tests.

DESIGN, SETTING, AND PARTICIPANTS

Prospective cohort study (2000-2002) of 987 individuals in California with stable coronary heart disease in the Heart and Soul Study, who were followed up for a mean of 3.7 (range, 0.1-5.3) years.

MAIN OUTCOME MEASURES

The association of baseline NT-proBNP levels with death or cardiovascular events (myocardial infarction, stroke, or heart failure). Traditional clinical risk factors, echocardiographic measures, ischemia, other biomarkers, and New York Heart Association classification were adjusted for to determine whether NT-proBNP levels were independent of other prognostic factors. Receiver operating characteristic (ROC) curves were used to assess the incremental prognostic value of adding NT-proBNP level to these other measures.

RESULTS

A total of 256 participants (26.2%) had a cardiovascular event or died. Each increasing quartile of NT-proBNP level (range of quartile 1, 8.06-73.95 pg/mL; quartile 2, 74-174.5 pg/mL; quartile 3, 175.1-459 pg/mL; quartile 4, > or =460 pg/mL) was associated with a greater risk of cardiovascular events or death, ranging from 23 of 247 (annual event rate, 2.6%) in the lowest quartile to 134 of 246 (annual event rate, 19.6%) in the highest quartile (unadjusted hazard ratio [HR] for quartile 4 vs quartile 1, 7.8; 95% confidence interval [CI], 5.0-12.1; P<.001). Each SD increase in log NT-proBNP level (1.3 pg/mL) was associated with a 2.3-fold increased rate of adverse cardiovascular outcomes (unadjusted HR, 2.3; 95% CI, 2.0-2.6; P<.001), and this association persisted after adjustment for all of the other prognostic measures (adjusted HR, 1.7; 95% CI, 1.3-2.2; P<.001). The addition of NT-proBNP level to standard clinical assessment and complete echocardiographic parameters significantly improved the area under the ROC curves for predicting subsequent adverse cardiovascular outcomes (0.80 for clinical risk factors and echocardiographic parameters plus log NT-proBNP vs 0.76 for clinical risk factors and echocardiographic parameters only; P = .006).

CONCLUSIONS

Elevated levels of NT-proBNP predict cardiovascular morbidity and mortality, independent of other prognostic markers, and identify at-risk individuals even in the absence of systolic or diastolic dysfunction by echocardiography. Level of NT-proBNP may help guide risk stratification of high-risk individuals, such as those with coronary heart disease.

B-type Natriuretic Peptide Is Not a Marker of Ischemia During Dobutamine Stress Echocardiography

Elevated levels of B-type natriuretic peptide (BNP) have been reported in association with exercise-induced ischemia. Data regarding BNP as a marker of ischemia during dobutamine stress echocardiography (DSE) are not conclusive. This study was designed to evaluate changes in BNP during DSE. A total of 74 patients referred to rule out ischemia by DSE were enrolled in the study. All patients had DSE using standard protocol. Of 74 patients enrolled, 6 were excluded because of nondiagnostic tests. Of the remaining 68 patients, 15 had positive DSE and 53 were negative for ischemia. The BNP levels (mean +/- SD) in the patients without ischemia were 42.5 pg/mL (+/-SD 47.6) at baseline and 41.9 pg/mL (+/-SD 48.9) at peak, and the measurements in the patients with ischemia were 90 pg/mL (+/-SD 171.7) at baseline and 88 pg/mL (+/-SD 149.2) at peak. BNP levels do not change during DSE with or without evidence of ischemia.

Direct Comparison of Brain Natriuretic Peptide (BNP) and N-Terminal Pro-BNP Secretion and Extent of Coronary Artery Stenosis in Patients With Stable Coronary Artery Disease

BACKGROUND

It is unclear whether coronary artery stenosis affects the secretion of N-terminal pro-brain natriuretic peptide (NT-proBNP) and brain natriuretic peptide (BNP) from the heart independent of ventricular dysfunction. Therefore, this study evaluated the relationship between BNP and NT-proBNP secretion, plasma levels and the severity of coronary artery stenosis in patients with stable coronary artery disease (CAD).

METHODS AND RESULTS

Plasma levels of BNP and NT-proBNP in the aortic root (AO) and coronary sinus (CS) in 251 consecutive patients with stable CAD were measured. The transcardiac increase of NT-proBNP was significantly increased with the severity of coronary artery stenosis (p=0.012), but that of BNP was not (p=0.116). The molar ratio of the (CS-AO) NT-pro-BNP/(CS-AO) BNP increased with the severity of coronary artery stenosis (p=0.019) and decreased after coronary revascularization (p=0.018, n=36). Step-wise multivariate linear regression analyses were used to detect independent predictors of the (CS-AO) NT-proBNP among 10 variables including hemodynamic parameters and the Gensini score, which is a measure of the extent and severity of CAD. Among these variables, left ventricular ejection fraction (p<0.0001), left ventricular end-diastolic pressure (p=0.003) and log Gensini score (p=0.008) were significant independent predictors.

CONCLUSION

These findings suggest that the transcardiac increase of NT-proBNP from the heart increases with the severity of coronary artery stenosis independent of hemodynamic overload, and plasma NT-proBNP may be superior to BNP to assess disease severity in CAD patients.

Brain natriuretic peptide and other risk markers for outcome assessment in patients with non-ST-elevation coronary syndromes and preserved systolic function

Several emerging cardiac markers constitute strong predictors among patients with coronary artery disease. In particular, brain natriuretic peptide (BNP), troponin T (TnT), and C-reactive protein (CRP) are related to increased risk of recurrent ischemic events and death. However, little is known about the utility of these biomarkers in combination. This study examined risk assessment in patients with coronary artery disease and preserved systolic function. We studied 208 consecutive patients (138 men, 70 women) with stable angina, unstable angina, and non-Q-wave myocardial infarction whose plasma BNP, TnT, and CRP levels were measured at hospital admission. All recruited patients underwent echocardiographic examination, and selective coronary angiography was performed. After adjusting for clinical presentation, age, gender, and common risk factors, BNP was demonstrated as a strong predictor of heart failure (6 months, odds ratio [OR] 2.03, 95% confidence interval [CI] 1.24 to 2.9, p <0.01; 12 months, OR 2.65, 95% CI 1.69 to 3.5, p <0.001) and mortality at 3, 6, and 12 months (p <0.001). BNP was also significantly related to extent of coronary artery disease and left anterior descending artery involvement (p <0.01). Patients with a BNP level >80 pg/ml in all 3 groups had a significantly poorer prognosis with increased incidence of heart failure and death. CRP was related to recurrent ischemic events (infarct or recurrent angina, OR 1.4, 95% CI 1.14 to 2.08, p <0.01) and was associated with major cardiac revascularization at 12 months (OR 1.51, 95% CI 1.29 to 1.73, p <0.001). TnT demonstrated a mild correlation with recurrent infarct or angina at 12 months (OR 1.1, 95% CI 0.96 to 1.22, p <0.05) but appeared related to multivessel coronary artery disease (OR 1.47, 95% CI 1.05 to 1.99, p <0.01). In conclusion, BNP appears to be associated with a long-term increased risk of mortality and heart failure in patients with apparently mild risk. BNP is also associated with a larger extent and greater severity of myocardial ischemia. Early BNP measurement could provide incremental information to TnT and CRP, and it may be the strongest independent predictor of cardiac outcome in subjects without left ventricular dysfunction or enlargement.

[The role of B type natriuretic peptide in the assessment of post myocardial infarction prognosis]

Recently cardiac peptides have received close attention as cardiovascular markers. Brain (B type) natriuretic peptide is a neurohormone synthesized predominantly in ventricular myocardium. Previous studies have shown that this hormone can provide prognostic information in patients with myocardial infarction. The aim of this review is to evaluate the impact of plasma levels of BNP on prediction of left ventricular ejection fraction and remodelling and major cardiac events after myocardial infarction.

A prospective cohort study of prognostic power of N-terminal probrain natriuretic peptide in patients with non-ST segment elevation acute coronary syndromes

BACKGROUND

Braintype natriuretic peptide (BNP) or N-terminal segment of the prohormone (NT-proBNP) measured within the first few days after symptom onset offer prognostic information in patients with non- ST elevation acute coronary syndromes (ACS).

METHODS AND RESULTS

This prospective cohort study included 493 patients with non-ST segment elevation ACS who underwent percutaneous coronary intervention in the Deutsches Herzzentrum and Klinikum rechts der Isar in Munich, Germany. NT-proBNP was measured on admission. Patients were divided into four groups according to quartiles of NT-proBNP. The primary end point of the study was mortality. Patients were followed for a median of 4.0 years [interquartile range 3.6 to 4.9 years]. During this time period, there were 65 deaths: 4 deaths in the 1st quartile, 9 deaths in the 2nd quartile, 16 deaths in the 3rd quartile and 36 deaths in the 4th quartile (Kaplan-Meier estimates of mortality: 3.4, 7.8, 16.0 and 33.9%; odds ratio [OR] 10.2, 95% confidence interval [CI] 4.5 to 23.5; P< 0.001 for 4th vs 1st quartile). Patients in the upper quartile of NT-proBNP had a more adverse cardiovascular risk profile than patients in lower quartiles of NT-proBNP. After adjustment in the Cox proportional hazards model, the NT-proBNP remained an independent correlate of mortality (adjusted hazard ratio [HR] 1.23, 95% confidence interval [CI] 1.04 to 1.45, P = 0.014 for 4th vs 1st quartiles) but weaker than age (adjusted HR 2.11, 95% CI 1.53 to 2.90; P < 0.001 for a 10-year increase in age) or left ventricular ejection fraction (adjusted HR 1.35, 95% CI 1.09 to 1.68; P = 0.007 for a 10% decrease).

CONCLUSION

N-terminal probrain natriuretic peptide is a marker of weak-to-moderate strength in predicting the long-term prognosis in patients with non-ST segment elevation acute coronary syndromes after percutaneous coronary intervention.

[Natriuretic peptides and multimarker approach to risk stratification of patients with acute coronary syndromes]

NATRIURETIC PEPTIDES IN ACUTE CORONARY SYNDROMES: Brain natriuretic peptides (BNP) and N-terminal prohormone brain natriuretic peptides (N-proBNP) have been shown to provide important prognostic information in patients with acute coronary syndrome (ACS). Ischemia may be an important stimulus for BNP release. This does not imply, however, that BNP is useful for diagnosing ischemia, and BNP is unlikely to prove sensitive or specific enough for this purpose. SIGNIFICANCE OF NATRIURETIC PEPTIDES IN ASSESSING PROGNOSIS IN PATIENTS WITH ACUTE CORONARY SYNDROMES: In patients with ST-elevation and non-ST-elevation myocardial infarction, higher BNP and N-proBNP levels have been shown to predict a greater likelihood of death or heart failure, independent of other prognostic factors. THERAPEUTIC IMPLICATIONS OF BNP ELEVATION IN ACUTE CORONARY SYNDROMES: Patients with BNP or NT-proBNP elevation following ACS are clearly at high risk for death and for developement of heart failure, but specific therapeutic implications of BNP elevation have not been defined. In particular, it is not known how patients with BNP elevation should be treated considering the fact that they have normal troponin levels and no clinical evidence of heart failure. MULTIMARKER STRATEGIES FOR RISK STRATIFICATION IN ACUTE CORONARY SYNDROMES: It has been shown recently that in patients with acute coronary syndromes the risk increased sequentially among those with one, two or three elevated biomarkers. THERAPEUTIC APPLICATIONS OF CARDIAC BIOMARKERS IN ACUTE CORONARY SYNDROMES: Multimarker strategies, that incorporate panels of cardiac biomarkers, are likely to be used in the future for risk stratification and for pathophysiologically-guided treatment of patients with ACS.