Prediction of outcome by neurohumoral activation, the six-minute walk test and the Minnesota Living with Heart Failure Questionnaire in an outpatient cohort with congestive heart failure.

AIMS: To compare the precursor of atrial and brain natriuretic peptide (N-ANP, N-BNP), brain natriuretic peptide (BNP), big endothelin-1, the 6-min walk test and the Minnesota Living with Heart Failure Questionnaire (LHFQ) with regard to short-term outcome in an ambulatory heart failure population. METHODS AND RESULTS: Ninety-six individuals (left ventricular ejection fraction of 26+/-10%) were included in the study. Within 1 day blood samples of N-ANP, N-BNP, BNP and big endothelin-1 were obtained, and the 6-min walk test and LHFQ were measured. The predictive power of these variables - including renin-angiotensin system antagonist therapy - in respect of 1-year event-free survival were calculated with a Cox regression analysis. All investigated variables had the power to predict outcome in a univariate analysis. Multivariate analysis revealed that N-ANP (chi-square=58 P<0.0001), BNP (chi-square=8 P<0.01), the LHFQ (chi-square=6 P<0.02) and the renin-angiotensin system antagonist (chi-square=4 P<0.05), are independent predictors. CONCLUSION: We conclude that, in an open clinical cohort of patients with large differences in the progression of the disease, N-ANP, BNP and LHFQ are the most reliable predictors of worsening heart failure in the short term. However, the dosage of the ACE inhibitor influenced short-term survival in this population.     

Effect of endoscopic transthoracic sympathicotomy on plasma natriuretic peptide concentrations in humans.

BACKGROUND: The effects of endoscopic transthoracic sympathicotomy (ETS) on plasma natriuretic peptides concentrations in humans were examined in order to elucidate the role of the sympathetic nervous system in their regulation. METHODS AND RESULTS: Thirty-seven patients with palmar hyperhidrosis underwent ETS. Cardiac functional indices were assessed by echocardiography, and plasma atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) concentrations were measured before and after ETS. ETS caused decreases in heart rate, mean arterial pressure, systemic vascular resistance, and increases in left ventricular (LV) end-diastolic volume, stroke index, ejection fraction, and left atrial diameter. LV end-systolic volume and cardiac index remained unchanged. Following ETS, ANP increased from 10.7+/-5.9 to 24.7+/-16.8 pg/ml (p < 0.01), and BNP increased from 5.1+/-4.2 to 19.7+/-21.5 pg/ml (p < 0.01). From the multivariate regression analysis, ETS, age and gender were determined to be significant predictors of changes in the ANP and BNP concentrations. None of the hemodynamic parameters were useful as independent predictors. CONCLUSION: The plasma concentrations of ANP and BNP increased after ETS, independent of hemodynamic changes, and apparently because of the release of the inhibitory effects of the cardiac sympathetic nerves on natriuretic peptide secretion.     

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

OBJECTIVES: This prospective study tested whether the natriuretic peptides predict cardiac death among patients using beta-blocking therapy after an acute myocardial infarction (AMI). BACKGROUND: Natriuretic peptides have provided prognostic information after AMI, but their predictive value has not been well established in the era of beta-blocker use. METHODS: A series of 521 patients (mean age 61 +/- 10 years) with AMI was included in the study. The end points were total mortality and non-sudden and sudden cardiac death (SCD). Plasma concentrations of atrial natriuretic peptide (ANP), N-terminal atrial natriuretic propeptide (N-ANP), brain natriuretic peptide (BNP), and ejection fraction (EF) were analyzed before hospital discharge. The cardiac medication was optimized (e.g., adherence to beta-blocking therapy was 97% at discharge and 95% at one year after AMI). RESULTS: During a mean follow-up of 43 +/- 13 months, total mortality was 11.5% (60/521), cardiac mortality was 6.3% (33/521), and 3.1% (16/521) experienced SCD. On univariate analysis, high levels of all measured peptides and low EF predicted the occurrence of non-SCD (p < 0.001 for all). Peptides and EF also predicted the occurrence of SCD (p < 0.05), with elevated BNP (>23.0 pmol/l) being the most powerful predictor (hazard ratio [HR] 4.4, 95% confidence interval [CI] 1.4 to 13.8; p = 0.01). After adjusting for clinical variables, only elevated BNP (HR 3.9, 95% CI 1.2 to 12.3, p = 0.02) and low EF (<40%) (p = 0.03) remained as significant predictors of SCD. CONCLUSIONS: Natriuretic peptides retain their prognostic value in the beta-blocking era among survivors of AMI. Elevated BNP provides information on the risk of subsequent SCD, independent of clinical variables and left ventricular EF.     

Plasma natriuretic peptide levels increase with symptoms and severity of mitral regurgitation

OBJECTIVES: This paper will describe associations between plasma natriuretic peptide levels and the severity and symptoms of mitral regurgitation (MR). BACKGROUND: A biochemical test that assisted grading of the severity of MR and the interpretation of symptoms would be of clinical value. METHODS: Forty-nine patients with isolated MR and left ventricular (LV) ejection fractions (EFs) of >55% underwent transthoracic echocardiography, assessment of symptoms, and measurement of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and its amino-terminal portion, N-BNP. RESULTS: The level of each natriuretic peptide rose with increasing severity of MR and with increases in left atrial (LA) dimensions (p < 0.001 for all comparisons), but no significant correlation existed between any natriuretic peptide and the LV dimensions or EF. Natriuretic peptide levels were higher in symptomatic MR (n = 16, BNP geometric mean 16.9 [95% confidence interval (CI) 13.3 to 21.4] pmol/l) compared with asymptomatic MR (n = 33, BNP 7.1 [95% CI 6.0 to 8.4] pmol/l, p < 0.001), and higher in asymptomatic MR than in normal controls (n = 100, BNP 5.3 [95% CI 4.8 to 5.8] pmol/l, p < 0.0001). These differences were similar for N-BNP and ANP and remained statistically significant (p < 0.05) after adjustment for echocardiographic measures of LV function and severity of MR. Both the sensitivity and the specificity for symptoms for the natriuretic peptides (area under receiver-operator characteristic curve for BNP = 0.90, N-BNP = 0.89, ANP = 0.89) were similar to the MR score (0.88) and greater than for LA dimension (0.81), vena contracta width (0.82), and LV end-systolic dimension (0.63). CONCLUSIONS: Plasma natriuretic peptides levels increase with the severity of MR and are higher in symptomatic compared to asymptomatic patients, even when LV EF is normal.     

Clinical significance of brain natriuretic peptide in patients with postmyocardial infarction

BACKGROUND: Risk stratification after acute myocardial infarction (AMI) includes the evaluation of left ventricular (LV) function. Natriuretic peptides, and particularly brain natriuretic peptide (BNP), emerged as a potential marker of ventricular function and prognosis after AMI. HYPOTHESIS: Brain natriuretic peptide levels are related to ventricular function, either systolic or isolated diastolic, and can give prognostic information in patients surviving AMI. METHODS: In all, 101 patients were enrolled. An echocardiographic (M-mode, two-dimensional, and pulsed Doppler) evaluation was performed and blood samples for BNP measurement were obtained. Clinical events were recorded during 12 months of follow-up. RESULTS: A negative correlation between BNP and LV ejection fraction was observed (r = -0.38; p < 0.001). The BNP levels were higher among patients with LV systolic dysfunction than in patients with isolated diastolic dysfunction (339.1 +/- 249.9 vs. 168.0 +/- 110.5 pg/ml, p = 0.001). The latter had higher levels of BNP than those with normal LV function (68.3 +/- 72.6 pg/ml, p < 0.001). The BNP accuracy to detect LV systolic dysfunction was good (area under the ROC curve [AUC] = 0.83) and increased when isolated diastolic dysfunction was also considered (AUC = 0.87). Brain natriuretic peptide had a very good accuracy in the prediction of death (AUC = 0.95) and the development of heart failure (AUC = 0.90). CONCLUSION: These results extend previous evidence relating BNP to systolic function after AMI. Furthermore, a relationship between BNP levels and diastolic function was found. Brain natriuretic peptide had a very good performance in detecting the occurrence of an adverse event. We conclude that BNP can detect high-risk patients and help select patients for more aggressive approaches.     

Plasma adrenomedullin relation with Doppler-derived dP/dt in patients with congestive heart failure

BACKGROUND: Increased circulating adrenomedullin (AM) concentration has been reported in congestive heart failure (HF) and considered as a possible marker of cardiac dysfunction. HYPOTHESIS: The study was undertaken to assess the relationship between circulating AM concentration and left ventricular (LV) functional state, estimated by echo-Doppler techniques in patients with mild to moderate HF and different degrees of LV dysfunction. METHODS: Plasma AM, B-type natriuretic peptide (BNP), and N-terminal (NT) proBNP levels were measured in 55 patients with HF (New York Heart Association [NYHA] I n = 8, II n = 26, III n = 21) and in 20 controls; dP/dt was calculated by the Doppler tracing of the mitral regurgitation jet. RESULTS: The study was completed in 51 patients. Adrenomedullin levels were higher than in controls (19.2 +/- 1.4 vs. 13.3 +/- 0.7, p < 0.005) and elevated in proportion to NYHA functional class. B-type natriuretic peptide and NT-proBNP were 344 +/- 67 vs. 12 +/- 2 pg/ml and 2196 +/- 623 vs. 52 +/- 4 pg/ml, respectively (p < 0.0001); dP/dt was better related to AM (r = 0.582, p < 0.001) than to the other peptides. Adrenomedullin was significantly (p < 0.001) different between patients grouped according to the dP/dt cut-off predictive of event-free survival. CONCLUSIONS: The combination of depressed contractility and increased AM may provide a clue for further characterization of the severity of LV dysfunction in HF, independent of baseline LV ejection fraction.     

Elevated B-type natriuretic peptide despite normal left ventricular function on rest and exercise stress echocardiography in mitral regurgitation.

AIMS: To determine whether elevated B-type natriuretic peptide (BNP) predicts left ventricular (LV) contractile dysfunction on exercise stress echocardiography in patients with severe mitral regurgitation (MR). METHODS AND RESULTS: Thirty three patients with moderate-to-severe or severe MR, a LV ejection fraction > or =60% and New York Heart Association Class I or II symptoms, and 12 controls underwent resting and exercise stress echocardiography. In 20 MR patients, BNP was within the normal range (mean +/- SD, 7.7 +/- 2.7 pmol/L), and in 13 MR patients, BNP was >12 pmol/L (19.6 +/- 7.6 pmol/L). LV end-systolic volume index after exercise was lower in controls than patients with MR (P < 0.0001), but similar in MR patients with normal and elevated BNP, respectively (controls 8.5 +/- 3.9, MR 20 +/- 7 vs. 20 +/- 9 cm(2)/m(2), P > 0.05). However, pulmonary artery systolic pressure (PAP) after exercise was higher in MR with high BNP (70 +/- 20 vs. 48 +/- 11 mmHg, <0.0001) and controls (38+/-11 mmHg). A two-fold increase in plasma BNP was associated with an average increase in resting PAP of 7.6 (95% CI 2.9, 12.2) mmHg, an increase in post-exercise PAP of 14.4 (95% CI 9.0, 19.9) mmHg and increase in left atrial area index of 2.1 (95% CI 0.5, 3.8) cm(2)/m(2). However, there was no significant association between the plasma level of BNP and any rest or post-exercise measure of LV systolic function (r < 0.25, P > 0.05 for all). CONCLUSION: The plasma level of BNP may be within the normal range in patients with moderate-to-severe or severe MR despite significant increases in LV end-systolic volume. Increase in BNP is associated with pulmonary artery hypertension on exercise and left atrial enlargement even when LV systolic function on exercise stress echocardiography is normal.     

The potential of brain natriuretic peptide as a biomarker for New York Heart Association class during the outpatient treatment of heart failure

BACKGROUND: Plasma C-terminal atrial natriuretic peptide (C-ANP), N-terminal ANP (N-ANP), and brain natriuretic peptide (BNP) have diagnostic utility in detecting left ventricular dysfunction. Their relative value in monitoring symptom status during the chronic treatment of congestive heart failure (CHF) remains undefined. METHODS AND RESULTS: Ninety-eight subjects with CHF were evaluated. Baseline natriuretic peptides were measured by radioimmunoassay, left ventricular ejection fraction (LVEF) was estimated with echocardiography, and New York Heart Association (NYHA) class was determined independently by attending heart failure specialists. Forty-one subjects were restudied during a 6- to 12-month follow-up period after optimizing therapy. At baseline, all natriuretic peptides and LVEF correlated positively with NYHA class (P <.005). Plasma BNP, however, correlated best with NYHA class. At follow-up, only changes of BNP correlated to changes of NYHA class (P =.04). BNP decreased (-45% +/- 12%, N = 14, P =.002) in subjects whose NYHA class improved whereas BNP remained unchanged (-1% +/- 10%, N = 25, P =.95) in those whose NYHA class was stable. CONCLUSIONS: This investigation demonstrates the superiority of plasma BNP as compared to ANP and LVEF in objectively assessing NYHA class during the chronic treatment of CHF. Given that clinical assessment of CHF is subjective, plasma BNP is a useful objective biomarker in monitoring human CHF in the outpatient setting.     

The effect of altering haemodynamics on the plasma concentrations of natriuretic peptides in heart failure

BACKGROUND: Natriuretic peptide levels reflect haemodynamics in patients with heart failure and may serve as biochemical markers of cardiac filling pressures. The purpose of this study was to detect differences in the kinetic profile between atrial natriuretic peptide (ANP), B-type natriuretic peptide (BNP) and their N-terminal fragments N-ANP and N-BNP, in response to rapid and persistent vasodilatation. METHODS: Sixteen men and four women aged 63.0+/-10.4 (mean+/-S.D.) with symptomatic congestive heart failure (NYHA III) and pulmonary capillary wedge pressure (PCWP)>18 mm Hg, received a 24-h infusion of nitroglycerin (N=8) or nicorandil (N=12). A reduction of PCWP was achieved for the duration of the study. Natriuretic peptides were measured by radioimmunoassay at baseline, 1, 3, 6, 12 and 24 h. RESULTS: PCWP and right atrial pressure fell rapidly and then increased modestly. ANP and N-ANP demonstrated a similar pattern. In contrast, BNP and N-BNP levels fell steadily throughout the observation period. This was accompanied by a continuous reduction of systemic vascular resistance (SVR). PCWP was highly correlated to the levels of all the natriuretic peptides. Using a longitudinal regression model evaluating responses over time, we found separate, significant relationships between all peptides and haemodynamic variables CONCLUSION: The atrial natriuretic peptides reflect rapid changes in filling pressures while the B-type peptides respond much slower. B-type peptides are less sensitive to short-term changes in filling pressures, but should reflect changes in SVR better during vasodilator therapy.     

N-terminal atrial natriuretic peptide and left ventricular geometry and function in a population sample of elderly males

OBJECTIVES: To investigate the relationships between N-terminal atrial natriuretic peptide (N-ANP) and left ventricular geometry and function. DESIGN: A cross-sectional study of a population-based cohort. SETTING: Follow-up of a health survey in Uppsala county, Sweden. SUBJECTS: Two hundred and five men aged 70. MAIN OUTCOME MEASURES: A Delfia sandwich immunoassay was used to measure the plasma levels of N-ANP. M-mode and Doppler echocardiographic examinations were used to measure left ventricular dimensions, mass, geometry and systolic function and to classify the subjects into four groups (normal geometry, concentric remodelling, concentric hypertrophy or eccentric hypertrophy). Left ventricular systolic dysfunction was defined as a left ventricular ejection fraction 相似文献   

Prognostic evaluation of neurohumoral plasma levels before and during beta-blocker therapy in advanced left ventricular dysfunction

OBJECTIVES: The study assessed the relative predictive potency of neurohumoral factors in patients with advanced left ventricular (LV) dysfunction during neurohumoral blocking therapy. BACKGROUND: The course of heart failure is characterized by progressive LV deterioration associated with an increase in cardiac (natriuretic peptides) and predominantly extracardiac (norepinephrine, big endothelin [big ET]) hormone plasma levels. METHODS: Plasma hormones were measured at baseline and months 3, 6, 12 and 24 in 91 patients with heart failure (left ventricular ejection fraction [LVEF] <25%) receiving 40 mg enalapril/day and double-blind atenolol (50 to 100 mg/day) or placebo. After the double-blind study phase, patients were followed up to four years. Stepwise multivariate regression analyses were performed with 10 variables (age, etiology, LVEF, symptom class, atenolol/placebo, norepinephrine, big ET, log aminoterminal atrial natriuretic peptide, log aminoterminal B-type natriuretic peptide [N-BNP] and log B-type natriuretic peptide [BNP]). During the study, the last values prior to patient death were used, and in survivors the last hormone level, New York Heart Association class and LVEF at month 24 were used. RESULTS: Thirty-one patients died from a cardiovascular cause during follow-up. At baseline, log BNP plasma level (x2 = 13.9, p = 0.0002), treatment allocation (x2 = 9.5, p = 0.002) and LVEF (x2 = 5.6, p = 0.017) were independently related to mortality. During the study, log BNP plasma level (x2 = 21.3, p = 0.0001) remained the strongest predictive marker, with LVEF (x2 = 11.2, p = 0.0008) log N-BNP plasma level (x2 = 8.9, p = 0.0027) and treatment allocation (x2 = 6.4, p = 0.0109) providing additional independent information. CONCLUSIONS: In patients with advanced LV dysfunction receiving high-dose angiotensin-converting enzyme inhibitors and beta-blocker therapy BNP and N-BNP plasma levels are both independently related to mortality. This observation highlights the importance of these hormones and implies that they will likely emerge as a very useful blood test for detection of the progression of heart failure, even in the face of neurohumoral blocking therapy.     

Reference ranges for natriuretic peptides for diagnostic use are dependent on age, gender and heart rate

BACKGROUND: Plasma natriuretic peptide levels may be useful in the diagnosis of heart failure. The available natriuretic peptide assays differ markedly in their performance characteristics. In addition, plasma levels are influenced by a number of factors including age and gender. AIMS: The aim of this study was to describe, in a healthy population, the influence of clinical and echocardiographic parameters on three natriuretic peptide moieties. METHODS: 1360 individuals were screened for the presence of left ventricular systolic dysfunction. We identified a cohort (n=720) of men aged 45-80 years (n=417) and women aged 55-80 years (n=303). None had history of cardiovascular disease or were taking any cardiovascular medication. All had normal echocardiographic and ECG findings. B-type (BNP), N-terminal pro-B-type (N-BNP) and N-terminal pro-Atrial (N-ANP) natriuretic peptides were assayed using in-house immunoluminometric assays. RESULTS: Of the considered clinical variables, only gender and heart rate (each P<0.005) were independently associated with levels of all three natriuretic peptides. Plasma levels of N-ANP (15%), BNP (25%) and N-BNP (75%) were higher in women compared to men. An increase in heart rate of 10 bpm corresponded to a reduction of 9% in N-ANP or BNP and a 15% reduction in N-BNP. Each 10 years of age was associated with 16% and 74% increase in ANP and N-BNP levels, respectively, but no increase in plasma BNP. Left ventricular ejection fraction could be assessed in 582 (81%) subjects and correlated positively with N-ANP (r(s)=6.48x10(-3), P<0.001) and BNP (r(s)=2.4x10(-2), P<0.001) but not N-BNP (P=0.405). No parameter of diastolic function was associated with any peptide level. CONCLUSIONS: In this healthy population, plasma levels of N-ANP, BNP and N-BNP were variably influenced by clinical covariates. While all three peptides were higher in women, only N-ANP and N-BNP were influenced by age. Levels of all peptides were inversely correlated with heart rate. Using this immunoluminometric assay, plasma BNP is not influenced by age, in contrast to N-ANP and N-BNP. In constructing normal ranges for diagnostic use, covariates such as age and gender must be considered, in addition to the format of assay being used.     

Identification of previously undiagnosed left ventricular systolic dysfunction: community screening using natriuretic peptides and electrocardiography

AIMS: We examined strategies to improve the positive predictive value of natriuretic peptides in screening for undiagnosed left ventricular systolic dysfunction (LVSD) in the community. METHODS AND RESULTS: The value of B-type(BNP), N-terminal proB-type (N-BNP) and N-terminal proAtrial(N-ANP) natriuretic peptides was prospectively assessed in 1360 subjects (45-80 years) together with echocardiography and electrocardiography. Seventeen individuals had definite and 13 had borderline, LVSD. Receiver-operating-characteristic (ROC) curve analysis showed the superiority of BNP (ROC areas 0.942 for definite LVSD, P<0.03; 0.934 for borderline LVSD, P<0.003) compared to N-BNP or N-ANP. Peptide levels, major ECG abnormality and ischaemic heart disease (IHD) history were independent predictors of LVSD. Logistic regression modelling incorporating these factors improved ROC areas for all natriuretic peptides. The specificity of all natriuretic peptides is enhanced by consideration of these factors. CONCLUSIONS: In population screening for definite LVSD, consideration of plasma natriuretic peptide levels together with the presence of major ECG abnormalities and IHD history reduces by a factor of six (in comparison to consideration of plasma natriuretic peptide levels in isolation) the number of subjects requiring echocardiography to detect one case of LVSD (for BNP, 44 falling to seven). Similar improvements were evident for N-ANP and N-BNP. Inclusion of major ECG abnormalities and IHD history improves the performance of any natriuretic peptide used in screening programmes for ruling in undiagnosed LVSD.     

Prognostic role of left atrial volume in elderly patients with symptomatic stable chronic heart failure: comparison with left ventricular diastolic dysfunction and B-type natriuretic peptide

BACKGROUND: Left atrial (LA) volume and B-type natriuretic peptide (BNP) represent powerful outcome predictors in patients with heart failure (HF).Aim: To assess the comparative prognostic role of LA volume (indexed to body surface area, LAVi), left ventricular diastolic dysfunction (LVDD) and BNP levels on long-term outcome in patients with symptomatic but stable chronic HF. methods: We studied consecutively 46 patients with symptomatic stable chronic HF (73 +/- 10 years, 30 men), in sinus rhythm, without significant valvular disease. Echocardiographic measurements included: LV mass, LV volumes and ejection fraction, and LAVi. LVDD was graded using a comprehensive Doppler algorithm. Blood taken before echocardiography was assayed for BNP levels. Primary end point was combined: all-cause mortality and hospitalization for worsening HF. RESULTS: During 20 +/- 14 months of follow-up 19 events occurred: 8 deaths, and 11 hospitalizations for HF. In univariate analyses LAVi, LVDD, BNP levels, LV ejection fraction, LV volumes, and LV mass were significant outcome predictors (P < 0.05). At multivariate regression LAVi was the only independent predictor of outcome (hazard ratio: 1.03 per 1 ml/m(2) increase, 95% CI: 1.01-1.06, P = 0.02). CONCLUSION: Although directly related to LVDD and to BNP levels, only LAVi emerged as an independent outcome predictor in this cohort of elderly patients with symptomatic stable chronic HF.     

Evaluation of impaired left ventricular ejection fraction and increased dimensions by multiple neurohumoral plasma concentrations.

BACKGROUND: A range of neurohumoral substances have been suggested as diagnostic markers in heart failure. It is, however, undetermined which marker has the greatest diagnostic potential, and whether additional information is gained by a comprehensive neurohumoral evaluation. AIMS: The purpose of the study was to compare the value of epinephrine, norepinephrine, renin activity, aldosterone (ALDO), atrial (ANP) and brain (BNP) natriuretic peptides, arginine-vasopressin and endothelin (ENDO) as markers for left ventricular (LV) dimensions and ejection fraction (LVEF) in patients with systolic heart failure. METHODS: Forty-eight patients with symptomatic heart failure were examined with blood samples and magnetic resonance imaging along with 20 age and gender-matched normal controls. RESULTS: In multiple regression analyses, BNP was the strongest independent marker for LV end-diastolic (r=0.71, P<0.0001), and end-systolic (r=0.75, P<0.0001) volumes, myocardial mass (r=0.69, P<0.0001), and LVEF (r=-0.78, P<0.0001). ANP was a supplementary independent marker for LV end-diastolic (r=0.76, P<0.0001) and end-systolic (r=0.78, P<0.0001) (ANP and BNP combined) volumes, ENDO for myocardial mass [r=0.71, P<0.0001 (ENDO/BNP)], and ALDO for LVEF [r=-0.81, P<0.0001 (ALDO/BNP)]. CONCLUSION: BNP is the strongest marker for LV dimensions and LVEF in patients with systolic heart failure. However, a comprehensive neurohumoral evaluation may add some information to the diagnosis.     

Comparison of B-type natriuretic peptide levels in patients with heart failure with versus without mitral regurgitation

Functional mitral regurgitation (MR) occurs most often in patients with heart failure (HF) and is associated with an adverse prognosis. Recently, B-type natriuretic peptide (BNP) has been validated as a marker of cardiac function and prognosis. We sought to assess the relation between functional MR and BNP levels in patients with HF, and hypothesized that MR is associated with higher BNP levels. In all, 201 patients admitted with the diagnosis of HF had a transthoracic echocardiogram and measurement of BNP levels within 48 hours. MR was graded as none/trace, mild, moderate, or severe using recently published guidelines of the American Society of Echocardiography. BNP was measured by a commercially available instrument (Biosite). The relation of MR to BNP was assessed using multivariable linear regression methods with a Tobin estimation to account for the truncation of BNP values at an upper limit of 1,300 pg/ml. Mean age of the patients was 67 +/- 11 years. The median BNP level was 826 pg/ml. The etiology of HF was predominantly diastolic in 64 patients (32%); 137 patients (68%) had significant left ventricular (LV) systolic dysfunction. Mean LV ejection fraction was 37 +/- 17%. MR was present in 112 patients (56%). After adjusting for clinical, hemodynamic, and echocardiographic variables, only LV ejection fraction (p = 0.016) and moderate or severe MR (p = 0.023) were significantly associated with BNP. When MR was grouped as any MR versus no MR, only LV ejection fraction (p = 0.017) and any degree of MR (p = 0.029) were significantly associated with BNP.     

Haemoglobin level influences plasma brain natriuretic peptide concentration

OBJECTIVE: It has been demonstrated that the haemoglobin (Hb) level is associated with the prognosis of congestive heart failure (CHF). Correction of anaemia has improved CHF outcomes even in patients without anaemia. Lower Hb level may play a more important role in left ventricular (LV) dysfunction than previously recognized. This study aimed to evaluate the association of Hb level with plasma brain natriuretic peptide (BNP) level as a marker of LV function adjusted for known determinants of BNP. METHODS AND RESULTS: Association of Hb level with plasma BNP level was studied in 279 outpatients of cardiology (mean age 61 +/- 16, 54% men) using multivariate regression analysis. Mean Hb level was 13.7 +/- 1.5 g/dl and 14% of patients had anaemia. Median BNP level was 28 pg/ml (range < 4 to 580 pg/ml). In total subjects, the multivariate model adjusted for age, sex, history of CHF, atrial fibrillation, serum creatinine level, LV wall motion abnormality, end-diastolic LV dimension, LV mass index, and cardiovascular risk factors showed that a lower Hb level was significantly associated with higher BNP level (p = 0.0243). In "normal" subjects who did not have a history of CHF, atrial fibrillation, LV wall motion abnormality, LV dilatation, valvular abnormality, or LV hypertrophy, a lower Hb level was significantly associated with a higher BNP level (p = 0.0012) after adjustment for age, sex, serum creatinine level, and cardiovascular risk factors. CONCLUSIONS: Lower Hb levels are associated with higher plasma BNP levels independent of age, sex, serum creatinine level, LV wall motion abnormality, LV hypertrophy, history of CHF, atrial fibrillation, and cardiovascular risk factors.     

Relation of B-type natriuretic peptide early after acute myocardial infarction to left ventricular diastolic function and extent of myocardial damage determined by magnetic resonance imaging

Early after acute myocardial infarction, the relation between plasma B-type natriuretic peptide (BNP) and extent of myocardial scar formation and diastolic dysfunction remains unclear. In 32 consecutive patients early (5 +/- 3 days) after a first acute myocardial infarction, delayed contrast-enhanced magnetic resonance (MR) imaging was performed to define myocardial scar. Diastolic function was assessed using phase-contrast MR measurements of mitral flow and septal tissue velocities (tissue MR imaging) to estimate left ventricular (LV) filling pressures. MR study was immediately followed by BNP measurement. BNP related to LV ejection fraction (r = -0.52, p = 0.002), extent of myocardial scar (percent delayed hyperenhancement of LV mass, r = 0.49, p = 0.005; transmural index, r = 0.58, p <0.001), and estimated LV filling pressures (ratio of early diastolic mitral flow velocity to early diastolic mitral annular velocity, r = 0.51, p = 0.003). In multivariate analysis, transmural index and early diastolic mitral flow velocity/early diastolic mitral annular velocity were independent predictors of BNP levels (p <0.05, power of 0.99 at alpha = 0.05). In conclusion, among patients with recent myocardial infarction, high BNP levels are independently associated with extent of myocardial scar tissue and estimated LV filling pressures.     

Relationship between B-type natriuretic peptides and pulmonary capillary wedge pressure in the intensive care unit

OBJECTIVES: We examined whether B-type natriuretic peptides (BNP) can serve as noninvasive markers of pulmonary capillary wedge pressure (PCWP) in the setting of critical illness. BACKGROUND: The BNP and N-terminal pro-B-type natriuretic peptide (NT-proBNP) are highly correlated with left ventricular (LV) filling pressures in patients with depressed LV systolic function. However, their relationship to PCWP in a heterogeneous intensive care unit (ICU) population has not been established. METHODS: We prospectively studied 40 patients in the ICU requiring invasive hemodynamic monitoring. Hemodynamics were recorded simultaneously with blood sampling for BNP and NT-proBNP. RESULTS: The BNP (median 420 pg/ml) and NT-proBNP (median 3,304 pg/ml) levels were markedly elevated, but weakly correlated with PCWP (BNP, r = 0.40, NT-proBNP, r = 0.32) and other cardiac parameters. Peptide levels were approximately four-fold greater in patients with impaired (estimated glomerular filtration rate [eGFR] <60 ml/min) versus normal (eGFR >60 ml/min) renal function, despite similar PCWP, cardiac index, and LV ejection fraction. In addition, both BNP and NT-proBNP showed stronger correlations with PCWP in patients with preserved (BNP, r = 0.58, NT-proBNP, r = 0.73) versus impaired renal function (BNP, r = 0.48, NT-proBNP, r = 0.34). Interaction terms between eGFR and BNP (p = 0.06) and NT-proBNP (p = 0.04) suggest that eGFR modulates the relationship of these peptides to filling pressures. CONCLUSIONS: The BNPs are markedly elevated, yet show only weak correlations to PCWP in ICU patients requiring invasive hemodynamic monitoring. Thus, a single value for BNP or NT-proBNP may not be a clinically useful noninvasive marker of filling pressures in the critically ill patient. This appears to be especially true in patients with impaired renal function.     

Doppler echocardiography-derived index of myocardial performance (TEI index): comparison with brain natriuretic peptide levels in various heart disease.

Plasma brain natriuretic peptide (BNP) has diagnostic and prognostic value in heart failure. Cardiac dysfunction varies from systolic or diastolic dysfunction alone to the combination of both. In the present study, Doppler echocardiographic parameters, including the Doppler echocardiography-derived index (TEI index), were compared with plasma BNP levels in 74 patients with various heart diseases. Blood sampling was performed before an echocardiographic examination was conducted. The TEI index was defined as the summation of isovolumic contraction and relaxation time divided by ejection time. In patients with left ventricular (LV) systolic dysfunction (ejection fraction <50%), the TEI index and BNP were increased significantly compared with patients with normal LV systolic function (p<0.05). Patients with a TEI index > or =0.45 showed significantly increased BNP levels compared with patients with a TEI index <0.45, irrespective of LV systolic function (241.4+/-451.2 vs 65.9+/-81.8pg/ml; p<0.05). The TEI index was significantly higher in patients with a BNP > or =73pg/ml than in patients with BNP <73pg/ml (0.57+/-0.24 vs 0.46+/-0.17; p<0.05). Other echocardiographic parameters did not correlate significantly with levels of plasma BNP. Of the echocardiographic parameters, a simple Doppler index (TEI index) that combines systolic and diastolic function can detect LV dysfunction in patients with high levels of plasma BNP in various heart diseases.