Use of Nesiritide (Human B-Type Natriuretic Peptide) in Infants Following Cardiac Surgery

We report the use of nesiritide in two infants following cardiac surgery. Both infants had increased intracardiac filling pressures postoperatively, despite traditional afterload reduction and diuretics. Both infants demonstrated clinical improvement with nesiritide therapy. There is currently limited data available describing the use of nesiritide in infants.     

B-Type Natriuretic Peptide Levels in Congenital Heart Disease

The objective of this study was to evaluate the potential role of B-type natriuretic peptide (BNP) levels in children with congenital heart disease undergoing cardiac catheterization. Measurement of plasma BNP concentration has been shown to be useful in the diagnosis, risk stratification, and management of adult patients with congestive heart failure, but little is known about the role of BNP in children with structural congenital heart disease. We measured plasma BNP levels using the Triage BNP test in patients with congenital heart disease referred for diagnostic or interventional cardiac catheterization. Plasma BNP concentration was measured in 96 children and 11 adults 19 years old (7.9 ± 8.3 years) undergoing heart catheterization for underlying congenital heart disease. BNP levels ranged from <5 to >1300 pg/ml, with a median BNP concentration of 19.0 pg/ml. Baseline BNP concentrations were >100.0 pg/ml on 19 occasions in 17 patients. The pressure difference between the left ventricle and ascending aorta was 10–110 mmHg in 21 patients. BNP concentrations for this cohort ranged from <5.0 to 1060.0 pg/ml and correlated with the degree of left ventricular outflow obstruction (correlation coefficient, 0.661; p = 0.001). This study suggests that with additional research, BNP concentration may prove to be a useful clinical tool in managing children and adults with congenital heart disease.     

Stress Transient Hypertrophic Cardiomyopathy and B-Type Natriuretic Peptide Role

This report describes a transient hypertrophic cardiomyopathy with right-ventricle outlet tract obstruction (RVOTO) induced by perinatal stress due to a major surgical procedure in a female newborn with congenital abnormalities. On day 10, she presented with heart failure, abnormal B-type natriuretic peptide (BNP), and an echocardiogram showing normal wall thickness. An in-hospital follow-up echocardiogram showed biventricular hypertrophy and RVOTO. At discharge, the infant was asymptomatic, with a normal echocardiogram and BNP. Transient RVOTO triggered by surgical stress and abnormal BNP have not been reported previously. Pathophysiology, the role of BNP, and clinical characteristics are discussed.     

急性心力衰竭患儿血浆脑钠素及心钠素水平的变化

目的探讨急性心力衰竭患儿血浆脑钠素(BNP)及心钠素(ANP)水平变化及其意义。方法选择不同病因的充血性心力衰竭(CHF)患儿46例及肺炎患儿40例、先天性心脏病患儿31例、健康儿童40例,应用酶联免疫吸附法分别检测血浆BNP及ANP水平,用多普勒超声心动图测量心力衰竭患儿心衰期及恢复期心脏指数(CI)及左室射血分数(LVEF)。结果CHF患儿心衰前期BNP即开始升高,心衰时达高峰(P<0.001),恢复期BNP水平渐下降,但仍高于正常值(P<0.001);心衰时心脏CI、LVEF均明显下降(P<0.01);CHF患儿心衰时升高的BNP水平与CI、LVEF均呈明显负相关(r=-0.61,0.79P均<0.05);同时测定的ANP动态变化趋势与BNP类似;CHF患儿心衰时的BNP/ANP比值远远高于正常对照;心衰时BNP与ANP异常率比较有显著差异(P<0.05);心衰时BNP水平与LVEF、CI值相关性优于ANP。结论CHF患儿血清BNP及ANP水平明显升高.且与心衰程度关系密切,BNP反映心脏功能改变较ANP更敏感,更具有特异性。     

Prognostic Value of B-Type Natriuretic Peptide in Surgical Palliation of Children with Single-Ventricle Congenital Heart Disease

The objective of this prospective study was to assess the prognostic role of perioperative B-type natriuretic peptide (BNP) levels in infants and children with single-ventricle congenital heart disease undergoing Norwood, bidirectional cavopulmonary anastomosis (BCPA), or Fontan operation. BNP levels were measured at baseline, after cardiopulmonary bypass, 6 to 12 hours after surgery, and then daily until indwelling vascular catheters were removed. Outcome measures included length of mechanical ventilation, inotropic support, and hospital stay. Twenty subjects underwent 23 surgical procedures (13 Norwood, 5 BCPA, and 5 Fontan). BNP levels were significantly higher in patients undergoing a Norwood procedure compared with a BCPA or Fontan procedure (p < 0.01). BNP levels measured 6 to 12 hours after surgery were predictive of duration of hospitalization (p = 0.005) and inotropic support (p = 0.01). An increase in BNP level within 48 hours of extubation was observed in 92% of patients undergoing a Norwood procedure. Early postoperative BNP levels correlate significantly with the ensuing duration of inotropic support and length of hospitalization. An increase in BNP after extubation may be reflective of the degree of underlying cardiopulmonary instability. Further investigation is necessary to define this important relation.     

Correlation of Plasma B-Type Natriuretic Peptide with Shunt Severity in Patients with Atrial or Ventricular Septal Defect

The goal of this study was to test the utility of bedside plasma concentration of B-type natriuretic peptide (BNP) assay as a screen for large shunts in pediatric patients with atrial septal defects (ASDs) and ventricular septal defects (VSDs). Thirty-five children at a mean age of 70 ± 129 weeks with ASD or VSD were included in the study. Nine patients had VSD and 26 had ASD. Plasma BNP values were compared with the Q _p/Q _s ratios derived from quantitative Doppler flow measurements. Mean BNP was 29 ± 42 pg/ml, with a range between <5 pg/ml and 208 pg/ml. Sixteen patients had Q _p/Q _s values >1.5 and 19 had values <1.5. The difference of mean BNP in these patient groups was statistically significant (45 ± 56 vs 14 ± 17, p = 0.03). BNP was positively correlated with shunt significance. Receiver operating characteristic curve analysis revealed a sensitivity of 69% and a specificity of 79% at a plasma BNP cut-off level of ≥20 pg/ml. Bedside measurement of BNP correlates with magnitude of ASD and VSD in children. BNP can provide information for the management of children with ASD or VSD. It can be used as part of the evaluation of a child with a preliminary diagnosis of a congenital defect.     

B-Type Natriuretic Peptide and Heart Failure in Patients with Ventricular Septal Defect: A Pilot Study

In adults without congenital heart disease, B-type natriuretic peptide (BNP) has been shown to be a very sensitive and specific marker of heart failure. The utility of BNP as a marker of clinical heart failure in children with a ventricular septal defect (VSD) has yet to be determined. A prospective, observational study evaluated BNP levels and other measures of heart failure. Eligible patients were <2 years old, scheduled to undergo surgical repair of a VSD, and without other significant structural heart disease. Data collected before and after surgical repair included echocardiographic measurements, electrocardiographic (ECG) findings, Ross score, BNP measurements, and weight gain. A total of 21 patients were enrolled and 14 patients had complete postoperative follow-up data. For patients with complete data, mean BNP decreased by 94 pg/ml (118 pre vs. 24 post; paired t-test, p = 0.041), mean left ventricular end-diastolic dimension z-score decreased by 1.75 (+0.86 vs. ?0.89; paired t-test, p = 0.013), mean weight z-score change per month increased by 0.35 (?0.25 vs. +0.10; Wilcoxon test, p = 0.013), and the incidence of biventricular hypertrophy on ECG decreased (46% vs. 0%; McNemar test, p = 0.031). The change in BNP showed a trend toward a negative correlation with weight z-score change per month (r = ?0.531, p = 0.075). In conclusion, BNP, along with other measures of heart failure, decreased following VSD repair, and the change in BNP was most closely correlated with improved weight gain.     

Atrial Natriuretic Peptide and Renin-Aldosterone Relationship in Healthy Newborn Infants

ABSTRACT. Plasma atrial natriuretic peptide (ANP) and aldosterone concentrations, and plasma renin activity (PRA) were measured by radioimmunoassay concurrently in 20 healthy full term infants, in cord blood, at 24 hours after birth and on the 4th day of life. ANP and aldosterone increased significantly at 24 hours and was persistently elevated on the 4th day of life. PRA remained unchanged during the first four days of life. In cord blood, ANP concentrations were correlated with aldosterone concentrations ( r = 0.49, p <0.05) and hematocrit ( r = 0.58, p <0.02). At the 24 hours of life, plasma ANP concentrations were correlated with weight loss observed on the 4th day of life ( r = -0.70, p <0.005), while the percentage changes in plasma aldosterone concentrations were correlated with percentage changes in systolic blood pressure (BP) ( r = 0.49, p <0.05). These findings suggest that during the early newborn period ANP and aldosterone act as an integrated system which has a role in regulation blood pressure and intravascular volume homeostasis.     

心力衰竭婴儿血浆脑利钠肽水平变化的意义

目的探讨心力衰竭(HF)婴儿血浆脑利钠肽(BNP)水平变化与HF严重程度的关系,及其对婴儿HF诊断、心功能分级和疗效监测的临床意义。方法随机选取2006年10月-2008年9月在本院儿科住院的HF婴儿30例为研究对象,并根据Ross分级标准将其分成轻、中、重度3组。在HF纠正前后收集HF婴儿血浆,检测BNP水平。随机选取本院体检中心健康婴儿30例为健康对照组。健康对照组和HF组婴儿血浆BNP水平测定采用化学发光微粒子免疫分析法;采用M型超声心动图测量HF组婴儿的左心室射血分数(LVEF),并分析血浆BNP水平与LVEF的相关性。结果HF婴儿血浆BNP水平[(629.17±508.53)×10-6ng.L-1]显著高于健康对照组[(65.13±31.98)×10-6ng.L-1](t=4.884,P<0.05)。HF程度越重,血浆BNP水平升高越显著,血浆BNP水平与LVEF呈负相关(r=-0.508,P<0.05),与心功能分级呈正相关(r=0.527,P<0.01)。HF纠正后血浆BNP水平[(105.02±57.81)×10-6ng.L-1]显著低于HF纠正前[(629.17±508.53)×10-6ng...     

Influence of Dopamine on Atrial Natriuretic Peptide Level in Premature Infants

ABSTRACT. The role of dopamine (DA) in the activation and/or release of atrial natriuretic peptide (ANP) was investigated in 11 premature infants during the early postnatal period. Mean plasma concentration of ANP and free DA level before DA infusion was 252.6±210 fmol/ml, and 0.4±0.2 ng/ml, respectively. DA infusion in a dose of 2μg/kg/min caused a rise in plasma free DA level to 59.7±21.5 ng/ml and a significant increase in GFR, diuresis, sodium excretion and fractional sodium excretion. The plasma concentration of ANP, however, remained unchanged (252.6±210.0 vs. 213±143.0 fmol/ml). Thus, our data failed to demonstrate a stimulatory effect of DA on ANP release in premature infants. The role of the high plasma concentration of ANP in preterm neonates immediately after birth has to be clarified.     

Utility of B-Type Natriuretic Peptide in Differentiating Congestive Heart Failure from Lung Disease in Pediatric Patients with Respiratory Distress

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

Right Ventricular Dysfunction and B-Type Natriuretic Peptide in Asymptomatic Patients After Repair for Tetralogy of Fallot

Early detection of right ventricular (RV) dysfunction is essential in the assessment of patients with repaired tetralogy of Fallot (TOF). This study aimed to assess latent RV dysfunction in asymptomatic patients with TOF and to determine the predictive value of B-type natriuretic peptide (BNP). Pressure–volume loops were recorded for 16 young patients (New York Heart Association class 1 or Ross class 0; median age, 14.2 years) using the conductance catheter technique. All the patients had RV dilation secondary to pulmonary regurgitation after surgical repair of TOF. Indexes of RV function were derived at baseline level and during dobutamine infusion. Contractility was calculated by the slope of the end-systolic pressure–volume relation (ESPVR). An increase in ESPVR during dobutamine infusion was considered to indicate contractile reserve as a marker for latent RV dysfunction. The median ESPVR significantly increased from 0.32 mmHg/ml (0.13–0.72 mmHg/ml) at baseline to 0.57 mmHg/ml (0.24–1.55 mmHg/ml) during dobutamine infusion (p = 0.005). However, for five patients, no relevant increase in contractility was found, indicating impaired RV contractile reserve. There was only a weak inverse correlation between impaired contractile reserve and BNP (r = −0.28). Even asymptomatic patients with only a mildly enlarged right ventricle can have impaired RV function. Early RV dysfunction cannot be predicted accurately with BNP.     

Changes in Plasma Concentrations of Atrial Natriuretic Peptide during Exchange Transfusion in Premature Infants

ABSTRACT. Plasma concentrations of atrial natriuretic peptide (ANP) and hemodynamic parameters were investigated in five premature infants undergoing exchange transfusion. Baseline values of ANP were 51.7 ± 21.2 fmol/ml. Volume depletion by withdrawal of 10 ml blood did not cause changes in systolic blood pressure (79.4 ± 4.3 vs. 71.4 ± 5.6 mmHg) and heart rate (115 ± 5.2 vs. 115 ± 2.4 b/min). ANP levels in plasma remained unaltered (53.4 ± 24.9 fmol/ml). Replacement of 10 ml blood increased central venous pressure by 33% and ANP concentration in the plasma by nearly 30%, while heart rate and blood pressure remained unchanged. Our data indicate that the heart of the premature infant responded to acute blood replacement with increased ANP-release, while blood removal appeared not to influence hormone regulation.     

Plasma B-Type Natriuretic Peptides in Children With Cardiovascular Diseases

Natriuretic peptides (NP) are released from the heart in response to pressure and volume overload. The biologic properties of NPs include counterregulation of the rennin-angiotensin-aldosterone pathway and a decrease in sympathetic tone resulting in diuresis, natriuresis, and vasodilation. Natriuretic peptides help to maintain fluid balance and blood pressure in a healthy physiologic range. The B-type natriuretic peptide (BNP) and its N-terminal precursor (NTpBNP) have become important diagnostic biomarkers of cardiovascular diseases (CVDs) in adults. Although many studies suggest that BNP also is a reliable test for diagnosing significant CVDs in children, data are lacking on whether additional use of BNP increases diagnostic accuracy and predicts prognosis. This comprehensive review describes the utility of BNP and NTpBNP for various CVDs of the neonatal and pediatric age groups. Because BNP is not a stand-alone test, it should not replace history, physical examination, or clinical judgment, but it has a clear value in adding details to the whole story for children, thus enabling the front-line physicians to make a diagnosis, especially in the acute care setting.     

Neonate With Vein of Galen Malformation and Heart Failure: Serial Changes in Plasma B-Type Natriuretic Peptide Following Endovascular Embolization

We report a neonate with vein of Galen malformation (VGM) who developed congestive heart failure (CHF) early after birth. Serial changes in plasma B-type natriuretic peptide (BNP) following an endovascular embolization procedure for VGM were mirrored in his clinical CHF status. The plasma BNP level markedly increased to 1800 pg/ml (normal, <100 pg/ml) in accordance with the severity of CHF. It rapidly decreased to 356 pg/ml during the first week after endovascular embolization for VGM. In the following 3 weeks there was an unexpected upward trend in plasma BNP despite echocardiography revealing normal biventricular function. After additional evaluation and treatment for CHF, BNP decreased again and the patient’s clinical status concurrently improved. The patient was discharged with a normal BNP level. Monitoring serial plasma BNP provides valuable information regarding the need for additional evaluation or treatment of newborns with CHF and may be used to document improvement.