N-terminal pro-brain natriuretic peptide on admission has prognostic value across the whole spectrum of acute coronary syndromes

Onset of neoaortic root dilation 18 years after an arterial switch operation

It has been claimed that neoaortic root dilatation or enlargement with aortic regurgitation is progressive until 11 years after an arterial switch operation. We report a case of neoaortic root dilatation onset occurring 18 years after operation and discuss the pathological features and the possible acting mechanisms.

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.

Early and mid-term outcome of the arterial switch operation in 114 consecutive patients

BACKGROUND

The arterial switch operation (ASO) has become the treatment of choice in patients with simple or complex transposition of the great arteries (TGA). The purpose of this study was to assess early and mid-term outcome after ASO in a single centre.

PATIENTS AND METHODS

Between 1995 and December 2005, 114 consecutive patients underwent an ASO at our institution, performed by one single surgeon. Patients charts, surgical reports and echocardiograms were retrospectively reviewed. Patients were analyzed in 3 different groups: Group I consisted of 77 neonates with TGA and intact ventricular septum, group II of 13 patients with TGA and ventricular septal defect which had to be closed surgically and group III of 24 patients with various forms of TGA in a complex setting. The patient's median weight was 3.23 kg (1.65-8.30). Twenty-five neonates were born preterm, 18 were diagnosed prenatally. Median follow-up time was 20.7 months (0.3-128.6).

RESULTS

The thirty day mortality was 1.75% (2/114), late mortality 0.88% (1/112) accounting for an overall mortality of 2.63%. There was only one early coronary event and so far no late events. Ten of 111 survivors required reoperation, all but 1 from group III. Prevalence of supravalvular pulmonary stenosis was 4.7%. Freedom from reoperation at 5 years of follow-up time was 87.5%. One patient required permanent pacing, no other late arrhythmias occurred. In our series the only risk factor for increased mortality and morbidity was a body weight of less than 2500 g at the time of operation. No better outcome could be demonstrated in the prenatally diagnosed patients.

CONCLUSION

The ASO can be performed safely and with low mortality and morbidity even in patients with complex TGA. Follow-up of these patients is required to detect residual problems like supravalvular pulmonary stenosis, coronary problems, arrhythmias and aortic valve dysfunction.

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.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

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.

Neurohormonal modulation in heart failure of ischemic etiology: Correlates with left ventricular remodeling

The natural progression of heart failure (HF) is accompanied by the compensatory activation of cardiac and extracardiac neurohormonal systems and changes in the anatomy and function of the left ventricle. The processes of ventricular remodeling and neurohormonal activation are mutually influenced so that strong associations may be observed between circulating concentrations of biomarkers (especially the natriuretic peptides originating from the heart) and parameters of left ventricle size and function. Temporal changes in the concentration of natriuretic peptides convey incremental prognostic value compared with a single determination and are usually related to concomitant changes in markers of left ventricle remodeling in patients with chronic HF. Whether knowledge of biomarkers' concentration can improve the clinical outcome of patients with HF by helping in guiding and monitoring their therapy treatment is a stimulating working hypothesis still to be verified.

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.

Amey S, Polanczyk CAA. Prognostic value of serum biomarkers in association with TIMI risk score for acute coronary syndromes

BACKGROUND

Markers of neurohormonal activation and inflammation play a pivotal role in non-ST-elevation acute coronary syndromes (NSTE-ACS).

HYPOTHESIS

We hypothesized that other biochemical markers could add prognostic value on Thrombolysis In Myocardial Infarction (TIMI) risk score to predict major cardiovascular events in patients with NSTE-ACS.

METHODS

In a cohort of 172 consecutive patients with NSTE-ACS, TIMI score was assessed in the first 24 h, and blood samples were collected for measurement of N-terminal pro-brain natriuretic peptide (NT-proBNP), high-sensitivity C-reactive protein, CD40 ligand, and creatinine. Major clinical outcomes (death and cardiovascular hospitalization) were accessed at 30 days and 6 months. Multivariate logistic regression was applied to identify markers significantly associated with outcomes and, based on individual coefficients, an expanded score was developed.

RESULTS

Of 172 patients, 42% had acute myocardial infarction. The unadjusted 30-day event rate increased with age (odds ratio [OR] = 1.03; 95% confidence interval [CI] 1.00-1.06), creatinine (OR = 2.4; 1.4-4.1), TIMI score (OR = 1.6; 1.2-2.2), troponin I (OR = 3.4; 1.5-7.7), total CK (OR = 2.7; 1.2-6.1), and NT-proBNP (OR = 2.9; 1.3-6.3) levels. In multivariate analysis, TIMI risk score, creatinine, and NT-proBNP remained associated with worse prognosis. Multimarker Expanded TIMI Risk Score [TIMI score + (2 X creatinine [in mg/dl]) + (3, if NT-proBNP > 400 pg/ml)] showed good accuracy for 30-day (c statistic 0.77; p < 0.001) and 6-month outcomes (c statistic 0.75; p < 0.001). The 30-day event rates according to tertiles of expanded score were 7, 26, and 75%, respectively (p < 0.01).

CONCLUSION

In NSTE-ACS, baseline levels of NT-proBNP and creatinine are independently related to cardiovascular events. Both markers combined with TIMI risk score provide a better risk stratification than either test alone.

B-type natriuretic peptide as an integrated risk marker in non-ST elevation acute coronary syndromes

BACKGROUND

Elevated B-type natriuretic peptide (BNP) levels show prognostic significance in patients with non-ST elevation acute coronary syndromes, but the underlying pathophysiology remains unclear.

METHODS

Two hundred and eighteen consecutive patients with non-ST elevation acute coronary syndromes were studied retrospectively. We compared clinical characteristics between groups with plasma BNP levels above or below the median value, and performed multiple logistic regression analysis to identify independent predictors of supramedian BNP levels.

RESULTS

Patients with supramedian BNP (>or=134 pg/ml) were more likely to be elderly (>or=75 years) with diabetes, prior myocardial infarction, and a history of coronary artery bypass grafting. They also had higher cardiac marker levels, a higher Killip class, a lower left ventricular ejection fraction, renal insufficiency (creatinine>or=1.5 mg/dl), and more 3-vessel disease. In multivariate analysis, the strongest independent predictor of supramedian BNP levels was 3-vessel disease (chi(2)=12.1), followed by old age (chi(2)=10.3), renal insufficiency (chi(2)=5.0), higher Killip class (chi(2)=4.2), and lower left ventricular ejection fraction (chi(2)=4.1). All 11 patients dying in hospital had supramedian BNP levels. Its elevation reflected the risk of 3-vessel disease and coronary artery bypass grafting regardless of troponin status.

CONCLUSION

In unselected patients with non-ST elevation acute coronary syndromes, an increase of BNP is correlated with the extent of myocardial ischemia, age, renal insufficiency, and ventricular dysfunction. It may be a useful biomarker integrating conventional risk factors for risk stratification in this population.

Plasma level of N terminal pro-brain natriuretic peptide as a prognostic marker in critically ill patients

We studied whether N-terminal pro brain natriuretic peptide (NT-pro BNP) measured at intensive care unit admission is an independent predictor of mortality in critically ill patients. We conducted a prospective observational cohort study enrolling 78 patients with APACHE II scores more than 12. Serum NT-pro BNP and cardiac troponin T were measured at admission, and echocardiography was performed within 24 h. The primary end-point was 30-day mortality. The median NT-pro BNP levels of the 22 (28.2%) patients who died were significantly more frequent than that of those who survived (8328 versus 1016 pg/mL; P = 0.001). Patients with NT-pro BNP levels more than 1900 pg/mL had significantly more frequent mortality (47.2% versus 11.9%; P = 0.03). This group also had more frequent moderate to severe left ventricular dysfunction (30.6% versus 9.5%; P = 0.02) and abnormal cardiac troponin T levels (33.3% versus 14.3%; P = 0.05). Multivariate analyses adjusted for APACHE-II revealed that a NT-pro BNP level more than 1900 pg/mL is an independent predictor of mortality.

Clinical laboratory findings associated with in-hospital mortality

The diagnostic approach and the clinical management of critically ill patients is challenging. The recognition of biomarkers related to in-hospital mortality is of importance for identification of patients at increased risk of death. Many prediction models assessing the severity of illness and likelihood of hospital survival were developed using logistic regression analyses. These models include several laboratory parameters, such as white blood cell counts, serum bilirubin, serum albumin, blood glucose, serum electrolytes and markers which reflect acid-base disturbances. Recently, several other biomarkers, including troponin, B-type natriuretic peptide (BNP), N-terminal proBNP, C-reactive protein, procalcitonin, cholesterol and coagulation related markers have emerged as clinically useful tools for risk stratification and mortality prediction of heterogeneous and more specific subgroups of critically ill patients. More investigations are required to verify whether risk stratification based on mortality-related biomarkers may translate into targeted treatment strategies to improve clinical outcome of the critical illness. Biomarkers which are related to in-hospital mortality are highlighted in the current review.

Cardiovascular risk with cyclooxygenase inhibitors: general problem with substance specific differences?

Randomised clinical trials and observational studies have shown an increased risk of myocardial infarction, stroke, hypertension and heart failure during treatment with cyclooxygenase inhibitors. Adverse cardiovascular effects occurred mainly, but not exclusively, in patients with concomitant risk factors. Cyclooxygenase inhibitors cause complex changes in renal, vascular and cardiac prostanoid profiles thereby increasing vascular resistance and fluid retention. The incidence of cardiovascular adverse events tends to increase with the daily dose and total exposure time. A comparison of individual selective and unselective cyclooxygenase inhibitors suggests substance-specific differences, which may depend on differences in pharmacokinetic parameters or inhibitory potency and may be contributed by prostaglandin-independent effects. Diagnostic markers such as N-terminal pro brain natriuretic peptide (NT-proBNP) or high-sensitive C-reactive protein might help in the early identification of patients at risk, thus avoiding the occurrence of serious cardiovascular toxicity.

Effects of volume and/or pressure overload secondary to congenital heart disease (tetralogy of fallot or pulmonary stenosis) on right ventricular function using cardiovascular magnetic resonance and B-type natriuretic peptide levels

The aim of this study was to analyze the effect of pressure and/or volume overload on right ventricular (RV) function and brain natriuretic peptide (BNP) levels in patients with surgically corrected congenital heart disease. Forty-two consecutive patients aged 17 to 57 years (median 30) with congenital heart disease (32 with tetralogy of Fallot and 10 with pulmonary stenosis) were examined. The RV systolic pressure was estimated using Doppler echocardiography. Cardiovascular magnetic resonance imaging was used to obtain the RV volumes, ejection fraction (EF) and corrected EF (cEF). Plasma BNP levels were determined by immunoradiometric assay. Patients were categorized as having volume overload when pulmonary regurgitation was > or =10% and pressure overload when the RV systolic pressure was >40 mm Hg. Patients with RV volume overload had a lower RVEF compared with patients with pressure overload (p = 0.02) and lower left ventricular EF (p <0.001). BNP was higher in patients with volume overload than in patients with pressure overload (p = 0.002). BNP correlated with pulmonary regurgitation, RVEF, RV cEF, and left ventricular EF. In linear regression analysis, RV cEF was an independent predictor for BNP, after adjustment for age. Without the parameter of RV cEF in the regression model, pulmonary regurgitation and RVEF were independently associated with BNP level, after adjustment for age. In conclusion, patients with RV volume overload had higher BNP levels and lower RV function than patients with RV pressure overload. BNP levels were independently associated with the degree of RV volume overload and RV function.

Release pattern of N-terminal pro B-type natriuretic peptide (NT-proBNP) in acute coronary syndromes

BACKGROUND

Recently it has been found that BNP and NT-proBNP provide independent prognostic information in patients with acute coronary syndromes (ACS). However, little data are available on the time course of NT-proBNP levels in relation to onset of symptoms.

METHODS AND RESULTS

We included 765 patients (236 females, aged 64 +/- 11 years) with an ACS (STEMI 42%, NSTEMI 41%, UAP 17%), who were referred for coronary angiography. NT-proBNP was assessed on admission and the next day. NT-proBNP values were related to the time duration from onset of symptoms until blood drawing with lowest values within 3 h and highest values 24-36 h after onset of symptoms (147 (64-436) pg/ml and 1099 (293-3795) pg/ml, respectively, p < 0.001). Highest values for NT-proBNP on admission were found in patients with NSTEMI compared to patients with STEMI and UAP (912 (310-2258) pg/ml) vs 262 (85-1282) pg/ml) vs 182 (74- 410) pg/ml; p < 0.001), but no difference was present between STEMI and NSTEMI the day after admission (1325 (532-2974) pg/ ml vs 1169 (555-3413) pg/ml; p = 0.676). In contrast NT-proBNP values remained unchanged in UAP (182 (74-410) pg/ml) vs 171 (53-474) pg/ml).

CONCLUSION

The time interval from onset of symptoms to first blood collection is an important determinant for NT-proBNP values on admission in patients with an ACS and needs to be considered in clinical practice.

N-terminal pro-B-type natriuretic Peptide predicts significant coronary artery lesion in the unstable angina patients with normal electrocardiogram, echocardiogram, and cardiac enzymes

BACKGROUND

Brain natriuretic peptide (BNP) and N-terminal pro-brain natriuretic peptide (NT-proBNP) are not specific for ventricular dysfunction and other cardiac processes, such as myocardial ischemia, may also cause elevation of these markers.

METHODS AND RESULTS

To determine whether elevation of NT-proBNP without elevation of cardiac specific markers can predict coronary artery disease (CAD), the serum level of NT-proBNP was measured in 161 patients with unstable angina (61.0+/-8.1 years, male 54.0%) with normal ventricular function (left ventricular ejection fraction >55% and no regional wall motion abnormality by echocardiography) and normal troponin I level (<0.05 ng/ml). In these patients, levels of C-reactive protein and myoglobin were normal and none had Q wave on electrocardiographic (ECG). The NT-proBNP level was higher in patients with CAD (n=74) than in patients without CAD (n=87) (173.1+/-231.6 vs 68.1+/-62.5 pg/ml, p<0.001). At the standard cut-off point of >200 pg/ml, elevated NT-proBNP level shows high probability of CAD (odds ratio, 10.1; 95% confidence interval, 2.6-38.7, p=0.001). The NT-proBNP level positively correlated with the extent of CAD (r=0.329, p=0.001). In multivariate analysis, the NT-proBNP was an independent predictor of CAD.

CONCLUSION

These results suggested that NT-proBNP is a useful screening test for CAD in the unstable angina patients with normal ECG, echocardiogram and cardiac enzyme levels.

The prognostic value of N-terminal proB-type natriuretic peptide

The heart is not only a pump, but also it is an endocrine organ. Cardiac stretch and overload stimulate the secretion of natriuretic peptides, which have a variety of beneficial actions, such as vasodilation and natriuresis. Cardiac-derived natriuretic peptides, especially B-type natriuretic peptide (BNP), have emerged as useful biomarkers for the diagnosis, and potentially the treatment, of heart failure patients. The inactive amino-terminal fragment of the BNP prohormone (NT-proBNP), which is more stable than mature BNP, has also been recognized as an aid in the diagnosis of left-ventricular systolic dysfunction. Furthermore, elevated NT-proBNP concentrations have been shown to be predictive of poor prognosis in a variety of cardiovascular diseases, suggesting that it could be useful for risk stratification of patients. This review summarizes current literature that has addressed the issue of NT-proBNP as a prognostic tool in heart failure, acute coronary syndromes and other conditions.

Difference in Elevation of N-Terminal Pro-BNP and Conventional Cardiac Markers Between Patients With ST Elevation vs Non-ST Elevation Acute Coronary Syndrome

BACKGROUND

N-terminal pro-B-type natriuretic peptide (NT-proBNP) is elevated in patients with acute coronary syndrome (ACS), and is a powerful predictor of long-term mortality. Differences in the clinical utility and pathophysiological implication of NT-proBNP and conventional cardiac markers in patients with ST elevation (STE) vs non-STE (NSTE) ACS were investigated in the present study.

METHODS AND RESULTS

Ninety consecutive patients admitted with acute chest pain and a diagnosis of unstable angina or acute myocardial infarction were analyzed. Patients with >or=Killip class II were excluded to focus on the effect of myocardial ischemia on the release of cardiac markers. The markers were measured on admission and analyzed according to the time from onset. Conventional cytosolic marker (creatine kinase-MB) and myofibril marker (troponin T: TnT) were both significantly higher in STE-ACS patients compared with NSTE-ACS patients. Conversely, NT-proBNP was significantly higher in NSTE-ACS patients than STE-ACS especially within 3 h of onset, suggesting a larger ischemic insult despite the smaller extent of myocardial necrosis compared with STE-ACS patients. There was no significant correlation between NT-proBNP level and left ventricular ejection fraction (LVEF) obtained at acute-phase echocardiography in either NSTE-ACS patients (LVEF 57.7+/-11.2%) or STE-ACS patients (LVEF 55.1+/-12.7%). Comparison between NT-proBNP and TnT levels revealed a marked difference of elevations, with significantly augmented elevation of NT-proBNP (p<0.001) in NSTE-ACS patients as compared with prominent elevation of TnT in STE-ACS patients.

CONCLUSIONS

NT-proBNP is an early sensitive marker of myocardial ischemia that rises much higher in the earlier phase as compared with conventional markers of myocardial damage, especially in NSTE-ACS patients.

Admission N-terminal pro-brain natriuretic peptide and its interaction with admission troponin T and ST segment resolution for early risk stratification in ST elevation myocardial infarction

OBJECTIVE

To assess the long term prognostic value of N-terminal pro-brain natriuretic peptide (NT-proBNP) on admission and its prognostic interaction with both admission troponin T (TnT) concentrations and resolution of ST segment elevation in fibrinolytic treated ST elevation myocardial infarction (STEMI).

DESIGN AND SETTING

Substudy of the ASSENT (assessment of the safety and efficacy of a new thrombolytic) -2 and ASSENT-PLUS trials.

PATIENTS

NT-proBNP and TnT concentrations were determined on admission in 782 patients. According to NT-proBNP concentrations, patients were divided into three groups: normal concentration (for patients < or = 65 years, < or = 184 ng/l and < or = 268 ng/l and for those > 65 years, < or = 269 ng/l and < or = 391 ng/l in men and women, respectively); higher than normal but less than the median concentration (742 ng/l); and above the median concentration. For TnT, a cut off of 0.1 microg/l was used. Of the 782 patients, 456 had ST segment resolution (< 50% or > or = 50%) at 60 minutes calculated from ST monitoring.

MAIN OUTCOME MEASURES

All cause one year mortality.

RESULTS

One year mortality increased stepwise according to increasing concentrations of NT-proBNP (3.4%, 6.5%, and 23.5%, respectively, p < 0.001). In receiver operating characteristic analysis, NT-proBNP strongly trended to be associated more with mortality than TnT and time to 50% ST resolution (area under the curve 0.81, 95% confidence interval (CI) 0.72 to 0.9, 0.67, 95% CI 0.56 to 0.79, and 0.66, 95% CI 0.56 to 0.77, respectively). In a multivariable analysis adjusted for baseline risk factors and TnT, both raised NT-proBNP and ST resolution < 50% were independently associated with higher one year mortality, whereas raised TnT contributed independently only before information on ST resolution was added to the model.

CONCLUSION

Admission NT-proBNP is a strong independent predictor of mortality and gives, together with 50% ST resolution at 60 minutes, important prognostic information even after adjustment for TnT and baseline characteristics in STEMI.

Amino-Terminal Pro-Brain Natriuretic Peptide Predicts Ventricular Arrhythmogenesis in Patients With Ischemic Cardiomyopathy and Implantable Cardioverter-Defibrillators

STUDY OBJECTIVES

Even in high-risk population groups, not all patients have the same risk of sudden cardiac death (SCD). Given the emerging data about the amino-terminal fragment of the brain natriuretic peptide prohormone (NT-proBNP) value in heart failure, we planned to evaluate the importance of NT-proBNP levels in predicting the occurrence of malignant arrhythmias in patients with ischemic cardiomyopathy and implantable cardioverter-defibrillators (ICDs).

DESIGN

Prospective study.

SETTING

Tertiary referral center.

PATIENTS

Thirty five ambulatory patients with previous myocardial infarction, left ventricular ejection fraction < 35%, and ICDs for primary prevention of SCD according to Multicenter Automatic Defibrillator Implantation Trial I criteria.

INTERVENTIONS

Venous blood samples for plasma NT-proBNP measurement were obtained after 30 min of supine rest from all patients at the beginning of the study. Patients were evaluated every 2 months, or sooner in cases of device discharges, during a 1-year follow-up period. Data concerning arrhythmias and device therapy were stored at the time of device interrogation on each follow-up visit.

MEASUREMENTS AND RESULTS

During 1-year follow-up, 11 of 35 patients (31.4%) received 18 antiarrhythmic device therapies for ventricular tachyarrhythmia (VT). Patients who experienced such arrhythmias had NT-proBNP levels of 997.27 +/- 335.14 pmol/L (mean +/- SD), whereas those without VT had NT-proBNP levels of 654.87 +/- 237.87 pmol/L (p = 0.001). An NT-proBNP cutoff value of 880 pmol/L had a sensitivity of 73%, a specificity of 88%, a positive predictive value of 80%, and a negative predictive value of 88% for the prediction of occurrence-sustained VT events.

CONCLUSION

To achieve the maximum benefit by ICD therapy, more precise risk stratification is required, even in high-risk, post-myocardial infarction patients. Plasma NT-proBNP levels comprise a promising method that could help in the better identification of a patient group with an even higher risk of sudden death.

Comparison of endothelial vasodilator function, inflammatory markers, and N-terminal pro-brain natriuretic peptide in patients with or without chronotropic incompetence to exercise test

OBJECTIVE

To investigate the role of endothelial function, inflammatory markers, and N-terminal pro-brain natriuretic peptide (NT-proBNP) in patients with impaired chronotropic response during exercise test.

METHODS

86 subjects were enrolled. Treadmill exercise test was conducted according to the modified Bruce protocols. Brachial ultrasound was used to measure endothelium dependent flow mediated vasodilatation (FMD). Chronotropic incompetence was defined as either failure to achieve 85% of the age predicted maximum heart rate or a low chronotropic index (< 0.8).

RESULTS

Of the 86 patients, 20 (23%) exhibited chronotropic incompetence. The patients were divided into three groups according to chronotropic index: group 1, < 0.8 (n = 20); group 2, 0.8-1.0 (n = 26); and group 3, > 1.0 (n = 40). Patients with impaired chronotropic response had significantly lower FMD than those with higher chronotropic response (mean (SD) 2.8 (1.9)% v 5.0 (2.8)% v 5.3 (2.5)%, p = 0.002, for groups 1, 2, and 3, respectively). Serum concentrations of high-sensitivity C reactive protein (hsCRP), monocyte chemoattractant protein-1 (MCP-1), and NT-proBNP were significantly higher in group 1 than in groups 2 and 3 (hsCRP: 19 (12) v 9 (6) v 9 (6) mg/l, p < 0.05; MCP-1: 140 (51) v 133 (60) v 108 (46) pg/ml, p = 0.046; NT-proBNP: 4760 (1980) v 3710 (850) v 3910 (1060) mg/l, p = 0.019, respectively). In addition, chronotropic index was significantly related to FMD (r = 0.380, p = 0.001) and inversely related to hsCRP (r = -0.267, p = 0.013). By multivariate analysis, impaired chronotropic response was significantly related to endothelial dysfunction (p = 0.012).

CONCLUSION

Patients with impaired chronotropic response to graded exercise had endothelial dysfunction, enhanced systemic inflammation, and higher NT-proBNP concentrations. These findings may partly explain the mechanism of chronotropic incompetence as a predictor of cardiovascular risk and increased mortality.

NT-proBNP in the differential diagnosis of acute dyspnea in the emergency department

OBJECTIVES

The purpose of this study was to verify the usefulness of NT-proBNP in the differential diagnosis of dyspnea in a population of patients presenting in the ER with breathlessness.

DESIGN AND METHODS

In samples from 122 patients presenting in the ER with acute-severe dyspnea and from 25 subjects enrolled as a "comparison group" (NORM), NT-proBNP levels were measured. Patients have been classified on the basis of discharge diagnosis: pulmonary disease (PD, n = 23), pulmonary concomitant to cardiac disease (MIXED, n = 17), pulmonary embolism (EMB, n = 8), cardiac disease (CARD, n = 56), acute myocardial infarction (AMI, n = 11) and other disease (OTHER, n = 7).

RESULTS

A significant difference in NT-proBNP values (P <or= 0.05) was found in CARD vs. PD as well as vs. NORM and OTHER groups. 1760 ng/L was the best cut-off value calculated from ROC analysis (AUC +/- SE 0.815 +/- 0.041). Comparing NT-proBNP values and ER diagnosis, a disagreement in 24 patients was observed. Using the discharge diagnosis as the "gold standard," four cases (17%) were found to be FP and 11 cases (46%) were FN according to ER diagnosis, while 2 patients showed false positive and 7 false negative NT-proBNP values.

CONCLUSIONS

NT-proBNP measurement represents a useful biochemical tool helping the ER physician in the rapid and reliable recognition of cardiac involvement in patients presenting in the ER with acute-severe dyspnea.

NT-ProBNP in Non–ST-Elevation Acute Coronary Syndrome

BACKGROUND

The role of N-terminal pro-brain natriuretic peptide (NT-proBNP) in the early treatment of patients with non-ST-elevation acute coronary syndrome (NSTACS) has been evaluated in 6 large studies that include >12,000 patients.

METHODS AND RESULTS

These studies convincingly show that this marker of cardiac performance is associated strongly with death and the risk of future congestive heart failure and carry important prognostic information that is independent from previous known risk factors in NSTACS. As such, NT-proBNP can be added to existing risk stratification models and multimarker approaches. There is some data that indicate that this marker might also be helpful in guiding decisions about coronary revascularization in these patients, but further studies are needed.

CONCLUSION

Before routine use of NT-proBNP in NSTACS, the extra cost of adding this new marker to the current routine markers and its impact on selection of treatment should be considered.

N-Terminal Pro-Brain Natriuretic Peptide in Arterial Hypertension: A Valuable Prognostic Marker of Cardiovascular Events

BACKGROUND

N-terminal pro-brain natriuretic peptide (NT-proBNP) provides important prognostic information in patients with chronic heart failure and in the general population. The aim of this study was to evaluate NT-proBNP as a prognostic marker of cardiovascular morbidity and death in a sample of subjects with hypertension and preserved left ventricular systolic function from the general population.

METHODS AND RESULTS

The study population was recruited from 4 general practitioners. The study participants (n = 569 subjects; ages, 50-89 years) completed a heart failure questionnaire and were submitted to blood pressure measurement, electrocardiography, echocardiography, and blood sampling. After exclusion of subjects with left ventricular ejection fraction of <50%, 270 subjects fulfilled the following criteria for hypertension: history of hypertension or blood pressure >150/90 mmHg. During 3 years of follow-up, 28 subjects (10.4%) reached the composite end point of death, stroke/transient ischemic attack, or myocardial infarction. After adjustment for cardiovascular risk factors, NT-proBNP (logarithmically transformed) independently predicted the risk of experiencing a composite end point (hazard ratio, 1.94; P < .0001), and death (hazard ratio, 2.28; P < .0001). The risk of having a composite end point (21 vs 7; P = .005) was significantly higher for subjects with NT-proBNP above the study median than for subjects with NT-proBNP below the study median.

CONCLUSION

In this sample of subjects with hypertension and preserved left ventricular systolic function from the general population, plasma NT-proBNP was found to be a valuable cardiovascular risk marker, independently of traditional risk factors and prevalent cardiovascular disease.

Elecsys NT-ProBNP and BNP Assays: Are There Analytically and Clinically Relevant Differences?

BACKGROUND

B-type natriuretic peptide (BNP; 77-108 amino acids) and its N-terminal (1-76 amino acids) counterpart, NT-proBNP, are cardiac biomarkers that have been established for the assessment of left ventricular dysfunction and congestive heart failure and provide prognostic and risk stratification information for patients with acute coronary syndrome. Various automated immunoassays currently are available for the measurement of these natriuretic peptides, but there are significant analytical differences, especially between BNP and NT-proBNP.

METHODS AND RESULTS

Recently published methods and results were reviewed.

CONCLUSION

Although there are significant pre-analytical and analytical differences between the Triage BNP and Elecsys NT-proBNP and other BNP methods, they do not translate to clinically significant differences in their diagnostic and prognostic application in the assessment of systolic heart failure and risk stratification of patients with acute coronary syndrome. However, there appears to be some evidence that suggests that NT-proBNP may have an advantage in the detection of patients with mild or asymptomatic heart disease.

Central nervous system outcomes in children with complex congenital heart disease

PURPOSE OF REVIEW

To provide a brief overview of our current understanding of the types of neurodevelopmental sequelae in congenital heart disease survivors and to review the most recent studies from the past year, which have focused on 4 interrelated issues: (1) outcome studies, (2) the mechanism and etiology of central nervous system injury in children with CHD, (3) perioperative monitoring for brain injury, and (4) strategies for neuroprotection during cardiac surgery.

RECENT FINDINGS

As the number of survivors of surgery for complex congenital heart disease continues to rise, it is recognized that there is an increased incidence of adverse neurological outcomes in the survivors. In particular, a pattern similar to that seen in premature infants is emerging, including learning disabilities, behavioral abnormalities, inattention and hyperactivity. Imaging studies have revealed a high prevalence of structural brain abnormalities and periventricular leukomalacia, fetal and postnatal cerebral blood flow is abnormal, postnatal oxygen delivery is decreased, and intraoperative support techniques and postoperative low cardiac output are associated with cerebral hypoperfusion.

SUMMARY

The causes of these late developmental abnormalities are most likely sequential, cumulative and multifactorial.

Cardiac Troponins and N-Terminal Pro-Brain Natriuretic Peptide in Acute Ischemic Stroke Do Not Relate to Clinical Prognosis

Background and Purpose— The prognostic value of cardiac troponins and natriuretic peptide in acute ischemic stroke is uncertain. We measured cardiac troponin T (cTnT), cardiac troponin I (cTnI), and N-terminal pro-brain natriuretic peptide (NT-proBNP) at admission in acute ischemic stroke patients without evident myocardial damage.

Methods— In 174 consecutive patients with MRI-confirmed ischemic stroke, serial measurements of cTnT, cTnI, and NT-proBNP were performed at 3 different time points in the hyperacute phase (at admission, on days 1 and 2). Relation of laboratory values to risk factors, stroke subtype classification, and clinical outcome after 3 months was analyzed.

Results— The highest proportion of raised parameters was found at day 2 for cTnI in 8 of 103 (7.8%), at day 3 for cTnT in 8 of 174 (4.6%), and NT-proBNP in 114 of 174 (65.5%) patients. Proportion of patients with good outcome was significantly reduced in the group with highest NT-proBNP quartile. However, using multivariate regression analysis, no significant relation to morbidity and mortality was found for cTnT, cTnI, or NT-proBNP. Significant impact on the outcome was detected for lesion size, insular involvement, sex, age, and stroke severity.

Conclusions— NT-proBNP is raised in nearly two thirds of acute stroke patients, whereas elevated cardiac troponins are found only in a small number of acute ischemic stroke patients. Neither NT-proBNP nor cardiac troponins influence clinical outcome if other risk factors are considered.

Analytical evaluation of the Dade Behring Dimension RxL automated N-Terminal proBNP (NT-proBNP) method and comparison with the Roche Elecsys 2010

Methods to quantify B-type natriuretic peptide (BNP) and N-terminal-propeptide (NT-proBNP) in plasma or serum samples are well established. We assessed the analytical performance of the Dimension RxL NT-proBNP method (Dade-Behring). Evaluation of different sample types was carried out. Controls and heparin plasma pools were used to determine the detection limit, precision, and linearity. Sample stability and the effect of interfering substances on the NT-proBNP concentrations were evaluated. Agreement between Dimension RxL and Elecsys 2010 (Roche Diagnostics) NT-proBNP methods was assessed. The influence of age and sex on NT-proBNP concentrations was evaluated in healthy subjects. Heparin plasma should be the matrix of choice. The detection limit was 2.0ng/L. The total imprecision was 2.6–3.6% for concentrations from 231 to 9471ng/L; mean NT-proBNP concentrations of 21 and 15ng/L were associated with coefficients of variation of 9.9% and 14.7%, respectively. The method was linear up to 32,650ng/L. There was no effect of temperature, freeze-thaw cycles and interfering substances. A bias was detected when Dimension RxL and Elecsys 2010 NT-proBNP methods were compared. Age and sex were significantly and independently related to NT-proBNP concentrations. The Dimension RxL NT-proBNP method, like the Elecsys 2010, is suitable for routine use in the diagnosis of heart failure.

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.