Cardiac natriuretic peptides: new laboratory parameters in heart failure patients

Natriuretic peptides, atrial natriuretic peptide and brain natriuretic peptide, are key regulators in the homeostasis of salt and water excretion and in the maintenance of blood pressure. During heart failure, these peptides are highly activated because of volume overload and increased myocardial wall tension. Among all natriuretic peptides and neurohormones, brain natriuretic peptide and its N-terminal prohormone fragment have been shown to be the best markers to identify patients with heart failure. They are useful prognostic markers as well. The stability of brain natriuretic peptides and N-terminal prohormones in ethylene-diamine-tetraacetic-acid whole blood is sufficient for routine use. Sensitive and specific assays without the need for plasma extraction are commercially available. The available data indicate that natriuretic peptides are powerful diagnostic and prognostic markers in heart failure patients. First data on treatment guidance are promising.     

Increased plasma levels of NT-proANP and NT-proBNP as markers of cardiac dysfunction in septic patients

The family of natriuretic peptides comprises several structurally related 22-53-amino acid peptides, such as atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP), which are vasoactive peptides with vasodilator and diuretic properties and play an important role in cardiovascular homeostasis. The salutary cardiovascular effects of natriuretic peptides suggest that ANP and BNP may have a pathophysiological significance in the cardiac dysfunction of septic patients. We determined plasma levels of the stable N-terminal prohormone forms of ANP (NT-proANP) and BNP (NT-proBNP) as well as troponin I (TNI) as a marker of myocardial cell injury by ELISA methods in 19 septic patients and 19 healthy controls at day one of severe sepsis. Left ventricular ejection fraction (LVEF) was determined on day 1 of severe sepsis by echocardiography. Significantly higher concentrations of NT-proANP were measured in non-survivors (mean = 13415 pmol/l +/- SEM = 4295) and survivors (mean = 7386 pmol/l +/- SEM = 1807) as compared to controls (mean = 1404 pmol/l +/- SEM = 181; p<0.001). Levels of NT-proBNP were also significantly higher in non-survivors (mean = 3439 pmol/l +/- SEM = 1246; p<0.05) and survivors (mean = 1009 pmol/l +/- SEM = 263; p<0.001) as compared to controls (mean = 200 pmol/l +/- SEM = 24) and correlated well with an increase in TNI-levels (r = 0.71; p<0.001). NT-proANP and NT-proBNP may serve as useful laboratory markers to indicate myocardial dysfunction and may help to differentiate between survivors and non-survivors of severe sepsis.     

Vigorous response in plasma N-terminal pro-brain natriuretic peptide (NT-BNP) to acute myocardial infarction

Acute myocardial infarction (MI) results in activation of neurohormonal systems and increased plasma concentrations of myocardial enzymes and structural proteins. We hypothesized that plasma levels of N-terminal pro-brain natriuretic peptide (NT-BNP) would respond more vigorously after MI than those of other natriuretic peptides. We also sought to compare this response with that of the established myocardial injury markers troponin T (TnT), myoglobin and creatine kinase MB (CK-MB). We obtained multiple blood samples for measurement of atrial natriuretic peptide (ANP), N-terminal pro-ANP, brain natriuretic peptide (BNP) and NT-BNP along with CK-MB, TnT and myoglobin in 24 patients presenting to the Coronary Care Unit within 6 h of onset of MI. Multiple samples were obtained in the first 24 h, then at 72 h, 1 week, 6 weeks and 12 weeks. NT-BNP increased rapidly to peak at 24 h and exhibited greater ( P <0.001) absolute increments from baseline compared with BNP and ANP, whereas NT-ANP did not change from baseline. Proportional increments in NT-BNP were also greater than those for the other natriuretic peptides ( P <0.05). Natriuretic peptide levels reached their peak around 24 h, later than peak TnT, CK-MB and myoglobin (peak between 1-10 h), and NT-BNP and ANP remained elevated on average for 12 weeks. Our present results, with detailed sampling of a cohort of acute MI patients, demonstrate greater absolute and proportional increments in NT-BNP than ANP or BNP with sustained elevation of these peptides at 12 weeks.     

Natriuretic peptide system: physiology and clinical utility

PURPOSE OF REVIEW: This review discusses the physiology of natriuretic peptides as a group and brain natriuretic peptide (BNP) in more detail. It will also highlight implications for the use of the natriuretic peptides in the diagnosis and treatment of patients with cardiovascular disease. RECENT FINDINGS: The heart secretes two major natriuretic peptides: atrial natriuretic peptide (ANP), which is synthesized in the atrial myocardium, and BNP, which is synthesized in the ventricular myocardium. Both ANP and BNP are released in response to atrial and ventricular stretch, respectively, and will cause balanced vasodilation, natriuresis, and inhibition of the sympathetic nervous system and the renin-angiotensin-aldosterone axis. BNP is reported to be the biochemical marker of choice for evaluating the acute risk of patients with cardiovascular disease states ranging from heart failure to myocardial ischemia. Increased blood BNP concentrations are highly predictive of the short- and long-term risk of cardiac death across the entire spectrum of acute coronary syndromes and in patients with decompensated congestive heart failure. Synthetic recombinant human BNP, which mimics the actions of endogenous BNP, has emerged as an important new therapeutic agent in patients with acute heart failure. SUMMARY: Current data suggest that single and serial plasma measurement of BNP concentrations is a useful tool in the diagnosis and risk stratification of patients with heart disease. Nesiritide, the human recombinant form of BNP, is a new promising parenteral treatment in decompensated heart failure.     

Pathophysiology and significance of natriuretic peptides in patients with end-stage kidney disease

Natriuretic peptides (NP), especially B type (BNP) and its N-terminal pro-B type natriuretic peptide (NT-proBNP), have long been regarded as biomarkers of volume overload and tools to exclude heart failure in the general population. However, their role in end-stage kidney disease (ESKD) is less certain given that BNP and NT-proBNP are excreted by the kidney and so serum concentrations of NPs are nearly universally elevated compared to controls. Nevertheless, the accumulated evidence suggests that serum concentrations of NPs in patients with ESKD show moderate or strong positive relationships with underlying heart disease, abnormal cardiac structure or function and mortality. Limited evidence also supports the role of BNP including NT-proBNP, ANP in some studies, rather than CNP or DNP in risk stratification among ESKD patients as well as the utility of BNP samplings pre- and post- hemodialysis. However, studies of the cut-off values of NPs have yielded inconsistent results, such that further large-scale studies are needed to clarify these issues. This review summarizes the pathophysiology and significance of NPs in ESKD patients, especially their potential role as risk stratification biomarkers in clinical management.     

Atrial natriuretic peptides: diagnostic and therapeutic potential

The natriuretic family consists out of three molecules that share significant amino acid sequence homologies and a looped motif. Atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) are similar in their abilities to promote natriuresis and diuresis, to inhibit the renin-angiotensin-aldosteroneaxis and to act as vasodilators. The understanding concerning the actions of the C-type natriuretic peptide is incomplete, but this new family member acts as a vasodilator. Plasma levels of ANP and BNP are elevated in patients with unstable angina, acute myocardial infarction, and with congestive heart failure. BNP may be superior to ANP as a prognosticator for risk stratification after myocardial infarction and is independent of left ventricular ejection fraction. ANP and BNP have little therapeutic potential while experimental work as well as clinical trials suggest that the inhibition of the catabolism of natriuretic peptides in particular in combination with ACE-inhibitors may be clinically beneficial.     

B-type natriuretic peptides: prognostic markers in stable coronary artery disease

Circulating concentrations of B-type natriuretic peptide (BNP) and the N-terminal fragment (NT) of its prohormone (proBNP) are related to cardiac function and have emerged as clinically useful tools for the diagnosis of heart failure and for the estimation of prognosis in patients with heart failure and acute coronary syndromes. Recent studies have also convincingly documented that both BNP and NT-proBNP are powerful, independent prognostic indicators in patients with stable coronary artery disease. The associations are strongest for the end-points of death and heart failure, whereas the association with cardiac ischemic events is weaker or nonexistent, after adjustment for confounding factors. Importantly, BNP and NT-proBNP appear to provide incremental prognostic information to conventional risk factors, including markers of ventricular function and ischemia. Data documenting that BNP or NT-proBNP measurements can be used to guide treatment decisions in patients with stable coronary artery disease are still lacking.     

Gene expression of natriuretic peptides and their receptors type-A and-C after myocardial infarction in rats

The purpose of this study was to investigate myocardial mRNA expression of brain natriuretic peptide (BNP) and atrial natriuretic peptide (ANP) in different regions of the heart at three different time points after induction of myocardial infarction (MI) in rats. Furthermore, we examined putative changes in mRNA expression of natriuretic peptide receptors (NPRs), NPR-A and NPR-C, in myocardium and peripheral organs. Substantial increase in the mRNA levels of both BNP and ANP in the infarcted as well as non-infarcted regions were observed after induction of MI. These findings were paralleled by elevated circulating concentrations of ANP, BNP and N-terminal proANP (Nt-proANP). In addition, the mRNA levels of the clearance receptor, NPR-C, were augmented in the infarcted and non-infarcted regions of the left ventricular wall (LV), while it was decreased in the kidneys and lungs 28 days post-MI. Based on these data, we propose that, in addition to increased myocardial secretion of BNP and ANP, reduced peripheral clearance by NPR-C may contribute to the observed increase in circulating plasma concentrations of the natriuretic peptides after induction of MI in rats.     

Renal dysfunction is a confounder for plasma natriuretic peptides in detecting heart dysfunction in uremic and idiopathic dilated cardiomyopathies

BACKGROUND: The diagnostic value of natriuretic peptides in uremic cardiomyopathy has not been defined, nor has the effect of a hemodialysis (HD) session on peptides. METHODS: We performed an observational study of 100 white adult outpatients in New York Heart Association class I-II, with neither diabetes nor ischemic heart disease, 50 of whom had idiopathic dilated cardiomyopathy (DCM) and 50 of whom had uremic cardiomyopathy and were undergoing HD. We measured plasma N-terminal proB-type natriuretic peptide (NT-proBNP), BNP, and atrial natriuretic peptide (ANP) both before and after a dialysis session. Doppler echocardiograms were evaluated. We performed multiple regression analysis on the logarithm of peptide concentrations using clinical, laboratory, and echocardio-Doppler data as explanatory variables. RESULTS: Mean peptide concentrations were higher in the HD group, with an HD:DCM ratio of 25 for NT-proBNP and 5 for BNP and ANP. Peptides were correlated with each other (r > 0.85). After HD, NT-proBNP significantly increased by 14%, BNP decreased by 17%, and ANP decreased by 56%. Predialysis concentrations correlated with postdialysis values (r > 0.85). A multiple regression equation significantly fitted the observed peptide concentrations, both pre- and postdialysis, using the same set of 4 variables: disease group (DCM or HD), diastolic pattern, left atrial volume, and body mass index. CONCLUSIONS: Renal dysfunction was a confounder for natriuretic peptides, which were present in higher concentrations in the uremic patients with milder cardiac dysfunction than in those with idiopathic DCM without renal dysfunction. Left diastolic function pattern and atrial volume were cardiac determinants of peptide concentrations in DCM and HD.     

Gene expression of natriuretic peptides and their receptors type-A and -C after myocardial infarction in rats

The purpose of this study was to investigate myocardial mRNA expression of brain natriuretic peptide (BNP) and atrial natriuretic peptide (ANP) in different regions of the heart at three different time points after induction of myocardial infarction (MI) in rats. Furthermore, we examined putative changes in mRNA expression of natriuretic peptide receptors (NPRs), NPR-A and NPR-C, in myocardium and peripheral organs. Substantial increase in the mRNA levels of both BNP and ANP in the infarcted as well as non-infarcted regions were observed after induction of MI. These findings were paralleled by elevated circulating concentrations of ANP, BNP and N-terminal proANP (Nt-proANP). In addition, the mRNA levels of the clearance receptor, NPR-C, were augmented in the infarcted and non-infarcted regions of the left ventricular wall (LV), while it was decreased in the kidneys and lungs 28 days post-MI. Based on these data, we propose that, in addition to increased myocardial secretion of BNP and ANP, reduced peripheral clearance by NPR-C may contribute to the observed increase in circulating plasma concentrations of the natriuretic peptides after induction of MI in rats.     

An experimental study of cardiac natriuretic peptides as markers of development of congestive heart failure

The use of cardiac peptide measurements as possible diagnostic tools in congestive heart failure has been extensively discussed in the recent literature. Therefore, the aim of this study was to establish a model of experimental chronic heart failure, and thereby perform a comparative study of secretion and circulating levels of the cardiac peptides atrial natriuretic peptide (ANP), N-terminal proatrial natriuretic peptide (N-terminal proANP) and brain natriuretic peptide (BNP) during evolving heart failure. Chronic heart failure was induced in seven pigs by rapid left atrial pacing for three weeks. The effects of failure induction were documented 24 h after pacemaker deactivation. Hemodynamic indices of cardiac preload, like pulmonary capillary wedge pressure (PCWP) and right atrial pressure (RAP), were all considerably increased compared to sham operated controls. Likewise, plasma endothelin-L, noradrenaline, renin activity, aldosterone and angiotensin II were all markedly increased. Heart failure was accompanied by significant increases in both estimated cardiac secretory rate and plasma concentrations of all three cardiac peptides, significantly correlated to the PCWP. The directional changes during evolving heart failure were similar, although the percentage increase in plasma BNP was much larger than for ANP and N-terminal proANP. In absolute molar terms, however, the BNP concentration changes were minor compared to those of the other two peptides. The larger percentage increase of BNP might indicate its superiority as a marker of heart failure development, provided a functional assay suitable for clinical use can be designed for a peptide circulating in this low concentration range.     

An experimental study of cardiac natriuretic peptides as markers of development of congestive heart failure

The use of cardiac peptide measurements as possible diagnostic tools in congestive heart failure has been extensively discussed in the recent literature. Therefore, the aim of this study was to establish a model of experimental chronic heart failure, and thereby perform a comparative study of secretion and circulating levels of the cardiac peptides atrial natriuretic peptide (ANP), N-terminal proatrial natriuretic peptide (N-terminal proANP) and brain natriuretic peptide (BNP) during evolving heart failure. Chronic heart failure was induced in seven pigs by rapid left atrial pacing for three weeks. The effects of failure induction were documented 24 h after pacemaker deactivation. Hemodynamic indices of cardiac preload, like pulmonary capillary wedge pressure (PCWP) and right atrial pressure (RAP), were all considerably increased compared to sham operated controls. Likewise, plasma endothelin-1, noradrenaline, renin activity, aldosterone and angiotensin II were all markedly increased. Heart failure was accompanied by significant increases in both estimated cardiac secretory rate and plasma concentrations of all three cardiac peptides, significantly correlated to the PCWP. The directional changes during evolving heart failure were similar, although the percentage increase in plasma BNP was much larger than for ANP and N-terminal proANP. In absolute molar terms, however, the BNP concentration changes were minor compared to those of the other two peptides. The larger percentage increase of BNP might indicate its superiority as a marker of heart failure development, provided a functional assay suitable for clinical use can be designed for a peptide circulating in this low concentration range.     

B-type natriuretic peptide (BNP) and N-terminal pro-BNP in obese patients without heart failure: relationship to body mass index and gastric bypass surgery

BACKGROUND: Further investigations are warranted to better characterize variables that may confound the clinical interpretation of plasma natriuretic peptide measurements, which are increasingly recognized to have diagnostic and predictive importance. METHODS: Blood samples (EDTA plasma) from patients (n = 206) attending clinics for the medical treatment and follow-up of obesity were analyzed for B-type natriuretic peptide (BNP; Bayer assay) and the N-terminal segment of its prohormone (NT-proBNP; Roche assay). Natriuretic peptide concentration ranges were evaluated in those without diagnosis of congestive heart failure (CHF) or chronic kidney disease (CKD). RESULTS: BNP and NT-proBNP were directly correlated (r = 0.87; P = 0.01), with NT-proBNP concentrations higher relative to BNP. Of obese patients without CHF or CKD, 21.6% (40 of 185) had NT-proBNP concentrations greater than the published assay upper reference limit. Concentrations of both natriuretic peptides were higher in patients currently exposed to beta blockers, patients with the diagnosis of hypertension or type 2 diabetes, and patients with a history of gastric bypass surgery. An inverse relationship between body mass index (BMI) and both BNP and NT-proBNP was evident. According to the National Institutes of Health, National Heart, Lung, and Blood Institute classification, more than 95% of the participants sampled in this study were either obesity class 2 (35 kg/m(2) < BMI < 39.9 kg/m(2)) or class 3 (BMI >or=40 kg/m(2)) CONCLUSIONS: A substantial proportion of obese patients without CHF or CKD have concentrations greater than the upper reference limit for NT-proBNP but not for simultaneously measured BNP. A history of gastric bypass surgery appeared to be a significant predictor of increased natriuretic peptide concentrations when assessed in a population of patients with class 2 or 3 obesity.     

Recent advances in point-of-care testing for natriuretic peptides: potential impact on heart failure diagnosis and management

Heart failure is a leading cause of morbidity and mortality worldwide. The presenting symptoms of heart failure are often nonspecific. The diagnosis of heart failure has traditionally relied heavily upon clinical exam findings, which are often subjective and have low sensitivity. Efficient and rapid diagnosis of heart failure in the emergency room setting can reduce health care costs, hospital admission and ER visits, and improve patient care. Natriuretic peptides are objective biomarkers that can help with diagnosis, prognosis and management of heart failure. The most extensively studied and clinically utilized natriuretic peptides include brain natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP). Point-of-care testing in the emergency room setting can result in faster triage times. Point-of-care testing can also be utilized in the outpatient setting for real-time management of patients with heart failure.     

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

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

Prohormone brain natriuretic peptide (proBNP), BNP and N-terminal-proBNP circulating levels in chronic hemodialysis patients. Correlation with ventricular function, fluid removal and effect of hemodiafiltration

BACKGROUND: Brain natriuretic peptide (BNP), N-terminal proBNP (NT-proBNP) and to a lesser extent prohormone proBNP are recognized as biochemical markers of left ventricular dysfunction. In renal failure, interpretation of natriuretic peptide remains unclear, as natriuretic peptide levels may be not only be dependent on cardiac function and dimensions but also on renal function, fluid volume and removal by dialysis procedure including hemodiafiltration (HDF). The purpose of this study was (i) to assess BNP, NT-proBNP and proBNP levels and their correlation with clinical and echocardiographic data in chronic hemodialysis patients, and (ii) to investigate basal level alteration following HDF. METHODS: Baseline clinical and echocardiographic parameters were collected in 31 dialysis patients without evidence of cardiac failure. Pre- and post-HDF BNP, NT-proBNP and proBNP concentrations were measured. Correlations between echocardiographic measurements and basal circulating peptides, between changes in peptide values and changes in fluid volume after HDF were investigated. RESULTS: Baseline plasmatic levels were elevated (BNP=517+/-840 pg/mL, NT-proBNP=5340+/-6132 pg/mL and proBNP=3569+/-4683 pg/mL) and correlated with left auricular diameter and left ventricular mass index. HDF session induced a significant decrease of 39%, 59% and 36% for BNP, NT-proBNP and proBNP levels, respectively. This decrease was not correlated to post-HDF fluid removal or weight decrease. Correlation between BNP and proBNP was stronger (r(2)=0.88) than between NT-proBNP and proBNP (r(2)=0.54). CONCLUSIONS: Despite their elimination, BNP, NT-proBNP and proBNP could be potential markers of left ventricular remodeling in chronic renal failure patients on hemodialysis. According to these results, their cut-off values, however, need to be re-evaluated.     

N-terminal pro-atrial natriuretic peptide as a biochemical marker of long-term interventional success after radiofrequency catheter ablation of paroxysmal supraventricular tachyarrhythmias.

Radiofrequency (RF) catheter ablation has been shown to be highly effective in the treatment of supraventricular tachycardias. Atrial natriuretic peptide (ANP) and brain natriuretic peptide (B-type natriuretic peptide; BNP) are secreted by the heart mainly in response to myocardial stretch induced by volume load. The aim of the present study was to determine the time course of the N-terminal prohormone forms of ANP (NT-proANP) and BNP (NT-proBNP) in patients undergoing radiofrequency (RF) catheter ablation for paroxysmal supraventricular tachycardias. Serial blood samples were taken from 13 patients with symptomatic paroxysmal supraventricular tachycardias undergoing RF ablation and from 13 age- and gender-matched healthy controls. Blood was taken before ablation (day 0, baseline), and at day one and day 120 after ablation. Levels of NT-proANP were significantly higher before RF ablation (4862+/-726 pmol/l) as compared to day one (2021+/-220 pmol/l) and day 120 after RF ablation (2470+/-349 pmol/l) (with p<0.01 on day one and p<0.05 on day 120; n=13). The size of the left atrium decreased from 41.0+/-5.5 mm before ablation to 34.9+/-5.9 mm (n=13; p<0.05) on day 120 as measured by M-mode echocardiography. Levels of NT-proBNP showed comparable values before and on day one and day 120 after ablation and were not significantly elevated as compared to healthy controls. NT-proANP levels are increased in patients presenting with paroxysmal supraventricular tachycardias and decrease one day after radiofrequency catheter ablation, possibly reflecting a transient reduction of ANP secretion from injured myocardial cells. Lower NT-proANP levels in the long-term time course may result from reduction of atrial volume load and reconstitution of atrial architecture after successful treatment of supraventricular tachycardias. NT-proANP may serve as a useful laboratory marker to describe the long-term interventional success after RF ablation.     

In-hospital brain natriuretic peptide and N-terminal prohormone brain natriuretic peptide variations are predictors of short-term and long-term outcome in acute decompensated heart failure

Acute decompensated heart failure is one of the most important causes of hospitalisation worldwide. Natriuretic peptides have shown their usefulness in the diagnosis and management of heart failure. Their variations during hospitalisation also appear useful to predict outcomes. In particular, data from the literature demonstrate that reduction from admission to discharge of brain natriuretic peptide and N-terminal prohormone brain natriuretic peptide in these patients is a predictor of future cardiovascular events.     

Monitoring the response to pharmacologic therapy in patients with stable chronic heart failure: Is BNP or NT-proBNP a useful assessment tool?

OBJECTIVES: B-type natriuretic peptides are biomarkers of heart failure (HF) that can decrease following treatment. We sought to determine whether B-type natriuretic peptide (BNP) or N-terminal proBNP (NT-proBNP) concentration changes occurred in parallel to changes in other measures of heart failure following treatment. METHODS: We conducted a systematic review of the literature for studies that assessed B-type natriuretic peptide measurements in treatment monitoring of patients with stable chronic heart failure. Selected studies had to include at least three consecutive measurements of BNP or NT-proBNP. RESULTS: Of 4338 citations screened, only 12 met all of the selection criteria. The selected studies included populations with a wide range of heart failure severity and therapy. BNP and NT-proBNP decreased following treatment in nine studies and was associated with improvement in clinical measures of HF. CONCLUSIONS: There was limited data to support using BNP or NT-proBNP to monitor therapy in patients with HF.     

B型钠尿肽及N末端B型钠尿肽原在临床应用中值得关注的几个问题

B型钠尿肽（BNP）及5N末端B型钠尿肽原（NT-proBNP）是由心脏分泌的两种肽激素。近年来研究表明，BNP和NT-proBNP对于心衰诊断具有较好的应用价值。我们检验工作者应在充分认识二者生物学特性的基础上，正确开展其检测工作，并指导临床应用。