natriuretic-peptide--brain and Asphyxia-Neonatorum

Persistent pulmonary hypertension of the newborn is often associated with meconium aspiration syndrome (MAS) or perinatal asphyxia.. To determine the effect of meconium or asphyxia on pulmonary arterial pressure and circulating levels of vasoactive substances, we conducted a prospective study of 54 term infants, including infants with meconium-stained amniotic fluid with normal (MSAF) or abnormal (MAS) chest X-ray findings, infants with perinatal asphyxia, and controls. The purpose of this study was to determine the group most likely to have elevated pulmonary arterial pressure and a disturbed balance between vasoactive substances.. To estimate the pulmonary arterial pressure by echocardiography, we used the ratio of the right to left systolic ventricular pressure (RVP/LVP ratio). We measured the plasma concentrations of endothelin-1 (ET-1), cyclic guanosine monophosphate (cGMP) as an indicator of nitric oxide (NO) production, and 6-keto-prostaglandin F(1)α (6-keto-PGF(1)α) for the estimation of prostacyclin concentration. We also measured KL-6 as a marker of lung injury.. The RVP/LVP ratio was significantly higher in the MAS group than the other groups on day 0. Although ET-1 and 6-keto-PGF(1)α levels were comparable among all groups, the cGMP level on days 3-5 and the KL-6 level throughout the first postnatal week were significantly higher in the MAS group.. It is possible that meconium aspiration delays normal decline of pulmonary vascular resistance shortly after birth through lung parenchymal injury. The subsequent increase of cGMP in MAS may be an adaptive response to prevent further elevation of pulmonary arterial pressure by inducing NO.

Topics: Asphyxia Neonatorum; Blood Pressure; Down-Regulation; Fetal Blood; Gestational Age; Humans; Infant, Newborn; Lung; Lung Injury; Meconium Aspiration Syndrome; Natriuretic Peptide, Brain; Parturition; Pulmonary Artery; Time Factors; Vascular Resistance

Topics: Asphyxia Neonatorum; Creatine Kinase, MB Form; Female; Humans; Infant, Newborn; Male; Naltrexone; Natriuretic Peptide, Brain; Peptide Fragments

We aimed to study the changes of serum N-terminal pro-brain natriuretic to peptide (NT-proBNP) levels after asphyxia-induced myocardial injury in children and explore the relationship between serum NT-proBNP levels and neonatal asphyxia.. One hundred and six cases of neonatal asphyxia were randomly selected for the study, including 46 severe cases with myocardial injury and 60 mild cases with no cardiac injury. Sixty-three healthy newborns were selected as the control group. The serum NT-proBNP level was detected using electrochemiluminescence. Creatine kinase MB (CK-MB) and serum sodium and calcium were measured simultaneously.. The serum NT-proBNP level in the myocardial injury group was significantly higher than that of the noncardiac injury and control groups (p < 0.01). Asphyxia serum NT-proBNP and cardiac enzymes were significantly correlated. The median value of neonatal NT-proBNP was 1491 pg/mL at postnatal Day 3 (P3) and 1077 pg/mL at postnatal Day 14 (P14). The cutoff value for children with myocardial injury was 3612.5 pg/mL; the area under the receiver operating characteristic curve was 0.80 (p < 0.001), with a sensitivity of 83.3%, a specificity of 80.5%, a positive predictive value of 82.8%, and a negative predictive value of 79.4%. After treatment, the serum NT-proBNP level in children with myocardial damage showed a significant decrease.. The serum NT-proBNP level can reflect myocardial injury in neonates with asphyxia and can guide its diagnosis.

Topics: Asphyxia Neonatorum; Biomarkers; Case-Control Studies; Female; Heart Injuries; Humans; Infant, Newborn; Male; Natriuretic Peptide, Brain; Peptide Fragments; Predictive Value of Tests

In recent years, the focus of interest of the scientific community is the application of heart markers as early indicators and prognostic parameters of perinatal asphyxia (PA). The aim of this study was to evaluate the significance of clinical application of heart markers in term newborns with perinatal asphyxia.. During a 3-year period we analyzed 91 full-term newborns (55 with and 36 without perinatal asphyxia). In all the subjects within the first 24-48 h after birth, we simultaneously determined serum concentrations of cardiac troponin I, brain natriuretic peptide, MB fraction of creatine kinase (CK-MB) and C-reactive protein.. In the group of full-term neonates with PA significantly higher levels of cardiac tropon-inI (p = 0.000), CK-MB fraction (p = 0.000), brain natriuretic peptide (p = 0.003) and C-reactive protein (p = 0.017) were found, compared to the group of healthy full-term newborns. In merged group (n = 91) cardiac troponin I level correlated with the fifth minute Apgar score (r = -0.637, p = 0.000) and the serum lactate concentration in the first 12h after birth (r = 0.529, p = 0.000). Early increase in cardiac troponin I > 0.135 microg/L predicted the risk of death with the sensitivity of 84.6% and specificity of 85.9%, while the increase in CK-MB fraction, brain natriuretic peptide and C-reactive protein did not have a predictive value with respect to a mortality outcome.. Among the tested cardiac markers, cardiac troponin I is the most sensitive and the only reliable early predictor of mortality in full-term neonates with perinatal asphyxia.

Topics: Asphyxia Neonatorum; Biomarkers; C-Reactive Protein; Creatine Kinase, MB Form; Heart Failure; Humans; Lactic Acid; Natriuretic Peptide, Brain; Prognosis; Troponin I

Vijlbrief et al. [Neonatology 2012;102:243-248] reported a beneficial effect of hypothermia on cardiac function after perinatal asphyxia indicated by low levels of B-type natriuretic peptide (BNP). Elevated troponin I plasma levels, however, reflects impairment of cardiomyocytes under hypothermic conditions. The importance of BNP and cardiac troponin I as biomarkers of cardiac dysfunction that may supplement or substitute Doppler echocardiography has been outlined. Using an asphyxia cardiac arrest (ACA) animal model under spontaneous hypothermia, we found a decrease in the activities of NADH-cytochrome c-oxidoreductase and succinate-cytochrome c-oxidoreductase in comparison to normothermic sham-operated controls. This observation indicates the impairment of the respiratory chain of heart mitochondria, which is accompanied by morphological changes in these mitochondria. Changed cardiac troponin I levels and respiratory chain complexes activity represent different but corresponding steps within the process of cardiomyocyte injury. Interestingly, liver and brain mitochondria remained unchanged under this condition. Patients could benefit from the control of mitochondrial function during hypothermic intervention. When indicated, substances could be supplemented that support mitochondrial function, e.g. antioxidative-acting vitamins and ubiquinone.

Topics: Asphyxia Neonatorum; Biomarkers; Female; Heart; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Male; Natriuretic Peptide, Brain; Troponin I

The aim of the study was to assess myocardial damage in infants due to perinatal hypoxia.. The findings of 29 infants with perinatal hypoxia and 20 healthy infants were compared. Blood gas analysis, serum lactate, cardiac troponin I (cTnI), troponin T (cTnT), creatine kinase-MB (CK-MB) and B-type natriuretic peptide (BNP) were evaluated. Echocardiography together with tissue Doppler imaging was performed.. cTnT, CK-MB and BNP were higher in patients at the first day. There were positive correlations between the left ventricular (LV) myocardial performance index (MPI) and cTnT at first day and also at first month. LV ejection fraction and fractional shortening were lower at first day and at first month in patients. Myocardial systolic (Sm) and diastolic (Em and Am) velocities at all segments were lower at first day, and interventricular septum Sm, LV Sm, LV Em, right ventricular Em and LV Am were still lower at first month in patients. Isovolumic relaxation time at all segments together with LV MPI was higher at first day, ejection time values were lower and MPI values were higher at all segments at first month in patients.. These findings demonstrated that the signs of myocardial damage due to perinatal hypoxia still present at first month.

Topics: Asphyxia Neonatorum; Case-Control Studies; Echocardiography; Heart Diseases; Humans; Hypoxia; Infant, Newborn; Infant, Newborn, Diseases; Myocardium; Natriuretic Peptide, Brain; Time Factors; Troponin I; Troponin T; Ventricular Dysfunction, Left; Ventricular Function, Left

Little is known about the effects of hypothermia on the cardiovascular system in term newborns with neonatal encephalopathy.. To evaluate whether mild hypothermia for neonatal encephalopathy is cardioprotective as indicated by the cardiac biomarkers cardiac troponin I (cTnI) and B-type natriuretic peptide (BNP).. This was an observational cohort study of infants treated for perinatal asphyxia. In infants, mild total body hypothermia treatment of 33.5°C during 72 h was initiated (n = 20). Samples of cTnI and BNP were collected before the start of hypothermia, at 24 and 48 h after birth, and after rewarming (84 h). BNP and cTnI values were then compared with BNP and cTnI values of asphyxiated infants not treated with hypothermia (n = 28).. No differences were found between the groups in clinical patient characteristics or inotropic support. The hypothermia-treated patients seemed to be clinically more affected (5-min Apgar score, p < 0.05; umbilical artery pH, p = 0.08), but showed similar encephalopathy scores. Significantly lower values for BNP were found in hypothermia- compared to nonhypothermia-treated infants at 48 h and at normothermia after rewarming [144 pmol/l (95-286) vs. 75 pmol/l (45-143), 182 pmol/l (73-341) vs. 43 pmol/l (24-163)]. No differences were found for cTnI concentrations between both groups.. The raised, but similar, cTnI values between hypothermia- and nonhypothermia-treated infants indicate similar myocardial damage in both groups. The lower BNP levels during hypothermia treatment suggest that hypothermia after perinatal asphyxia exerts a beneficial effect on cardiac function.

Topics: Adaptation, Physiological; Apgar Score; Asphyxia Neonatorum; Biomarkers; Cardiomyopathies; Cohort Studies; Female; Gestational Age; Heart; Hemodynamics; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn; Intensive Care Units, Neonatal; Male; Natriuretic Peptide, Brain; Troponin I

Topics: Asphyxia Neonatorum; Biomarkers; Female; Heart; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Male; Natriuretic Peptide, Brain; Troponin I

To investigate the changes and the clinical significance of N-terminal pro-brain natriuretic peptide (NT-proBNP) and glycogen phosphorylase isoenzyme BB (GPBB) levels in neonates with asphyxia complicated by myocardial injury.. Sixty-four neonates with asphyxia (39 mild, 25 severe) were enrolled. Of the 64 neonates, 30 had myocardial injury and 34 did not develop myocardial injury. Twenty-five healthy neonates served as a control group. Plasma levels of NT-proBNP and GPBB were measured using ELISA. Myocardial enzymes and cardiac troponin I were stimultaneously measured, and electrocardiography and chest radiographs were obtained.. The plasma levels of NT-proBNP and GPBB in neonates with myocardial injury were significantly higher than those in neonates without myocardial injury and in the control group (P<0.01). The neonates with severe asphyxia had significantly increased plasma NT-proBNP and GPBB concentrations compared to those with mild asphyxia and the control group (P<0.01). Spearman rank correlation analysis showed that plasma NT-proBNP level was positively correlated with plasma GPBB level in neonates with asphyxia. Plasma levels of NT-proBNP and GPBB were also positively correlated with plasma levels of CK-MB, CK and LDH (P<0.01).. Both NT-proBNP and GPBB can be used as biomarkers of myocardial injury in neonates with asphyxia. The measurement of plasma NT-proBNP and GPBB levels was useful in early identification of myocardial injury and severity evaluation in neonates with asphyxia.

Topics: Asphyxia Neonatorum; Cardiomyopathies; Creatine Kinase, MB Form; Enzyme-Linked Immunosorbent Assay; Female; Glycogen Phosphorylase; Humans; Infant, Newborn; Male; Natriuretic Peptide, Brain; Peptide Fragments

Guanosine 3',5'-cyclic phosphate (cGMP) is known to be the second messenger of natriuretic peptides and nitric oxide (NO). To investigate the involvement of natriuretic peptides in the regulation of the feto-placental circulation, specific radioimmunoassays were used to measure the concentrations of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and cGMP in the umbilical venous plasma of normal and asphyxiated newborns. The plasma concentrations of ANP, BNP and cGMP in asphyxiated newborns were 48.3 +/- 12.9 pm, 24.5 +/- 9.4 pm and 4.4 +/- 1.6 nM (mean +/- s.e.m., n = 10), respectively. These values were significantly higher than those in the normal newborns (17.4 +/- 1.9 pm, 4.7 +/- 1.0 pm, and 0.78 +/- 0.14 nM, respectively). Moreover, the expression of both ANP-A and ANP-B receptor, biologically active receptors for natriuretic peptides, was detected in term human placenta by Northern bolt analysis. The expression of natriuretic peptide receptors was further confirmed by binding assay using [125I]-labelled ANP and solubilized crude membrane preparations of placental tissue. These findings suggest that cGMP is produced in the placenta, at least partly, by the action of ANP and BNP secreted from fetal heart, in pathophysiological conditions such as fetal hypoxia.

Topics: Asphyxia Neonatorum; Atrial Natriuretic Factor; Base Sequence; Blotting, Northern; Cell Membrane; Cyclic GMP; Humans; Infant, Newborn; Molecular Sequence Data; Natriuretic Peptide, Brain; Nerve Tissue Proteins; Placenta; Receptors, Atrial Natriuretic Factor; Reference Values; Umbilical Veins