Cardiac injury biomarkers in paediatric age: Are we there yet?

The aim of this article is to evaluate the clinical utility of cardiac injury biomarkers in paediatric age. In December 2015, a literature search was performed (PubMed access to MEDLINE citations; http://www.ncbi.nlm.nih.gov/PubMed/ ). The search strategy included the following medical subject headings and text terms for the key words: "cardiac injury biomarkers", "creatine kinase-MB", "myoglobin", "troponin", "children", "neonate/s", "newborn/s", "infant/s" and echocardiography. In the paediatric population, troponins show a good correlation with the extent of myocardial damage following cardiac surgery and cardiotoxic medication and can be used as predictors of subsequent cardiac recovery and mortality. Elevation of cardiac injury biomarkers may also have diagnostic value in cases when cardiac contusion or pericarditis is suspected. Cardiac injury biomarkers are very sensitive markers for the detection of myocardial injury and have been studied in healthy newborns, after tocolysis, intrauterine growth restriction, respiratory distress and asphyxia. The proportion of newborns with elevated troponin was higher than that in ill infants, children, and adolescents and in healthy adults, suggesting that myocardial injury, although clinically occult, is common in this young age group. Results suggest that significant elevation of cord troponin is an excellent early predictor of severity of hypoxic-ischaemic encephalopathy and mortality in term infants. Cardiac biomarkers may also benefit centres without on-site echocardiography with evidence showing good correlation with echo-derived markers of myocardial function. Further studies are needed to better clarify the role of cardiac biomarkers in paediatric age and their correlation with echocardiographic parameters.

Oxidative stress and nitric oxide are increased in obese children and correlate with cardiometabolic risk and renal function.

Oxidative stress and nitric oxide (NO) appear to represent important links between obesity and cardiovascular, metabolic and/or renal disease. We investigated whether oxidative stress and NO production/metabolism are increased in overweight and obese prepubertal children and correlate with cardiometabolic risk and renal function. We performed a cross-sectional evaluation of 313 children aged 8-9 years. Anthropometrics, 24-h ambulatory blood pressure, pulse wave velocity (PWV), insulin resistance (homoeostasis model assessment index (HOMA-IR)), inflammatory/metabolic biomarkers, estimated glomerular filtration rate (eGFR), plasma total antioxidant status (TAS), plasma and urinary isoprostanes (P-Isop, U-Isop), urinary hydrogen peroxide (U-H2O2), and plasma and urinary nitrates and nitrites (P-NOx, U-NOx) were compared among normal weight, overweight and obese groups, according to WHO BMI z-score reference. U-Isop were increased in the obese group, whereas U-NOx were increased in both overweight and obese children. U-Isop were positively correlated with U-H2O2, myeloperoxidase (MPO), high-sensitivity C-reactive protein, HOMA-IR and TAG. TAS correlated negatively with U-Isop and MPO and positively with PWV. HOMA-IR and U-H2O2 were associated with higher U-Isop, independently of BMI and eGFR, and total cholesterol and U-H2O2 were associated with U-NOx, independently of BMI, eGFR values and P-NOx concentration. In overweight and obese children, eGFR decreased across P-NOx tertiles (median: 139·3 (25th, 75th percentile 128·0, 146·5), 128·0 (25th, 75th percentile 121·5, 140·4), 129·5 (25th, 75th percentile 119·4, 138·3), P for linear trend=0·003). We conclude that oxidant status and NO are increased in relation to fat accumulation and, even in young children, they translate into higher values of cardiometabolic risk markers and affect renal function.

The Utility of Brain Natriuretic Peptide in Pediatric Cardiology: A Review.

OBJECTIVE: The aim of this article is to evaluate the clinical utility of brain natriuretic peptide in pediatric patients, examining the diagnostic value, management, and prognostic relevance, by critical assessment of the literature. DATA SOURCES: In December 2015, a literature search was performed (PubMed access to MEDLINE citations; http://www.ncbi.nlm.nih.gov/PubMed/) and included these Medical Subject Headings and text terms for the key words: "brain natriuretic peptide," "amino-terminal pro-brain natriuretic peptide," "children," "neonate/s," "newborn/s," "infant/s," and "echocardiography." STUDY SELECTION: Each article title and abstract was screened to identify relevant studies. The search strategy was limited to published studies in English language concerning brain natriuretic peptide/amino-terminal pro-brain natriuretic peptide in pediatric patients. DATA EXTRACTION: Data on age, gender, type of clinical condition, brain natriuretic peptide assay method, cardiac function variables evaluated by echocardiography, and prognosis were extracted. DATA SYNTHESIS: Brain natriuretic peptide reference values in healthy newborns, infants, and children are presented. Brain natriuretic peptide diagnostic accuracy in newborns, infants, and children suspected to have congenital heart defects is discussed, and brain natriuretic peptide prognostic value reviewed. The data suggest that the determination of brain natriuretic peptide levels improves the diagnostic accuracy in the assessment of heart disease in the pediatric population. Brain natriuretic peptide assay may increase the accuracy of neonatal screening programs for diagnosing congenital heart defects. Echocardiographic variables correlated to brain natriuretic peptide levels. Additionally, brain natriuretic peptide levels predicted adverse outcomes in the postoperative period. CONCLUSIONS: Brain natriuretic peptide assessment is a reliable test to diagnose significant structural or functional cardiovascular disease in children. In the integrated follow-up of these cases, several physiologic and clinical variables must be considered; brain natriuretic peptide may be an additional helpful marker. Nevertheless, larger prospective studies are warranted to elucidate the true prognostic value of brain natriuretic peptide in pediatric patients.

Paediatric dilated cardiomyopathy: clinical profile and outcome. The experience of a tertiary centre for paediatric cardiology.

Dilated cardiomyopathy is the most common form of cardiomyopathy in the paediatric population and an important cause of heart transplantation in children. The clinical profile and course of dilated cardiomyopathy in children have been poorly characterised. A retrospective review of 61 patients (37 female; 24 male) diagnosed with dilated cardiomyopathy from January, 2005 to June, 2012 at a single institution was performed. The median age at diagnosis was 15 months. Heart failure was present in 83.6% of patients and 44.3% required intensive care. The most prevalent causes were idiopathic (47.5%), viral myocarditis (18.0%) and inherited metabolic diseases (11.5%). In viral myocarditis, Parvovirus B19 was the most common identified agent, in concurrence with the increasing incidence documented recently. Inherited metabolic diseases were responsible for 11.5% of dilated cardiomyopathy cases compared with the 4-6% described in the literature, which reinforces the importance of considering this aetiology in differential diagnosis of paediatric dilated cardiomyopathy. The overall mortality rate was 16.1% and five patients underwent heart transplantation. In our series, age at diagnosis and aetiology were the most important prognosis factors. We report no mortality in the five patients who underwent heart transplantation, after 2 years of follow-up.

Living with CHD: quality of life (QOL) in early adult life.

AIMS: The aim of this study was to assess the quality of life, psychiatric morbidity, and the psychosocial adjustment of adolescents and young adults with CHD, and determine which variables play a role in buffering stress and promoting resilience and which ones have a detrimental effect; and to investigate the situation on school performance and failures, social and family support, physical limitations, and body image of these patients. METHODS: The study enrolled 137 CHD patients (79 male), with age ranging from 12 to 26 years old (M=17.60±3.450 years). The patients were interviewed regarding social support, family educational style, self-image, demographic information, and physical limitations. They responded to questions in a standardised psychiatric interview (SADS-L) and completed self-reported questionnaires for the assessment of quality of life (WHOQOL-BREF) and psychosocial adjustment (YSR/ASR). RESULTS: We found a 19.7% lifetime prevalence of psychopathology in our patients (27.6% in female and 13.9% in male). Of them, 48% had retentions in school (M=1.61 year±0.82). The perception of quality of life in CHD patients is better compared with the Portuguese population in the social relationships and environmental dimensions. However, it is worse in complex forms of CHD than in moderate-to-mild ones, in cyanotic versus acyanotic patients, in moderate-to-severe versus mild residual lesions, in patients submitted versus those not submitted to surgery, in patients with versus without physical limitations, and patients who have need for medication versus those who do not. Social support is very important in improving quality of life of patients in all dimensions as well as academic performance. CONCLUSIONS: Female patients and patients with poor academic performance and poor social support have worse psychosocial adjustment and perception of quality of life.

[Long term psychosocial outcomes of congenital heart disease in adolescents and young adults].

OBJECTIVE: Congenital heart disease (CHD) is a chronic illness with a high frequency in the worldwide population, and is normally diagnosed at birth or in uterus. Because of better conditions in diagnosis and early medical and surgical treatment, patients have survival rates of 90% and go further and further in life, facing different challenges in life cycle. In this study, we tested the effects of different demographic, clinical and psychosocial variables on the perception of quality of life (QOL), on psychosocial adjustment (PSA) and psychiatric morbidity (PM) of adolescents and young adults with CHD. We aimed to evaluate QOL, PM and PSA of adolescents and young adults with CHD and to determine which variables (demographic, clinical, and psychosocial) play a role in buffering stress and promoting resilience and which ones have a detrimental effect. METHODS: The study enrolled 150 CHD patients (87 males and 63 females), 12 to 26 years (17.45±3.373 years). The participants were interviewed regarding social support, family educational style, self-image, demographic information and physical limitations. They responded to questions in a standardized psychiatric interview (SADS-L) and completed self-reports questionnaires for assessment of QOL (WHOQOL-BREF) and PSA (YSR/ASR). RESULTS: We found a 18.7% lifetime prevalence of psychopathology in our participants (25.4% in females and 13.8% in males). 57.1% had retentions in school (1.53±0.804 year). The perception of QOL of CHD patients is better compared to the Portuguese population in the social relationships, environmental, physical and general dimensions. However, it is worse in female CHD patients and patients with poor academic performance and social support as well as in patients with complex or cyanotic CHD, moderate-to-severe residual lesions and physical limitations, and undergoing surgery. All of these variables, except presence of cyanosis, are also associated to a worse PSA. CONCLUSIONS: Female patients and patients with poor academic performance and poor social support refer worse PSA and QOL.

Association between blood pressure and angiotensin-converting enzymes activity in prepubertal children ∗.

OBJECTIVES: Angiotensin-converting enzymes' (ACEs) relationship with blood pressure (BP) during childhood has not been clearly established. We aimed to compare ACE and ACE2 activities between BMI groups in a sample of prepubertal children, and to characterize the association between these enzymes' activities and BP. METHODS: Cross-sectional study of 313 children aged 8-9 years old, included in the birth cohort Generation XXI (Portugal). Anthropometric measurements and 24-h ambulatory BP monitoring were performed. ACE and ACE2 activities were quantified by fluorometric methods. RESULTS: Overweight/obese children demonstrated significantly higher ACE and ACE2 activities, when compared to their normal weight counterparts [median (P25-P75), ACE: 39.48 (30.52-48.97) vs. 42.90 (35.62-47.18) vs. 43.38 (33.49-49.89) mU/ml, P for trend = 0.009; ACE2: 10.41 (7.58-15.47) vs. 21.56 (13.34-29.09) vs. 29.00 (22.91-34.32) pM/min per ml, P for trend < 0.001, in normal weight, overweight and obese children, respectively]. In girls, night-time systolic BP (SBP) and diastolic BP (DBP) increased across tertiles of ACE activity ( P < 0.001 and P  = 0.002, respectively). ACE2 activity was associated with higher night-time SBP and DBP in overweight/obese girls ( P  = 0.037 and P  = 0.048, respectively) and night-time DBP in the BMI z-score girl adjusted model ( P  = 0.018). Median ACE2 levels were significantly higher among nondipper girls (16.7 vs. 11.6 pM/min per ml, P  = 0.009). CONCLUSIONS: Our work shows that obesity is associated with activation of the renin-angiotensin-aldosterone system, with significant increase of ACE and ACE2 activities already in childhood. Also, we report sex differences in the association of ACE and ACE2 activities with BP.

Quality of life of patients with congenital heart diseases.

OBJECTIVES: To assess the perception of the quality of life of adolescents and young adults with congenital heart disease and to examine the variables that have a negative impact on it and that add a resilience effect. METHODS: A total of 22 male and 18 female patients, aged 12-26 years, of whom 27 were admitted to surgery and 13 were not, participated in this study. All patients had complete medical records and were interviewed once; demographic and clinical data were collected, and patients filled a questionnaire on quality of life, the WHOQOL-BREF, and underwent an interview on social support, educational style, self-image, functional limitations, and emotional adjustment. RESULTS/CONCLUSIONS: Our patients showed a better perception of quality of life than did the general population, on the basis of psychological, social relationship and environment scales. Older patients hold a better perception of quality of life on the psychological scale. Cyanosis did not show any significant impact over perception of quality of life decay; however, the number of surgical procedures and the persistence of moderate-to-severe residual injuries had considerable detrimental effect. Social support had an impact on increasing resilience, promoting adjustment to illness. Several factors may play a role in adjustment to congenital heart disease, either improving the perception of quality of life or worsening it. We may conclude that some buffer variables on congenital heart disease may play roles in increasing the perception of quality of life of patients during their lifetime, social support probably explaining why the perception of quality of life is better than in the normal population. The number of surgeries and the moderate-to-severe residual injuries, however, reverted that effect.

Impact of physical activity on redox status and nitric oxide bioavailability in nonoverweight and overweight/obese prepubertal children.

Nutritional status might contribute to variations induced by physical activity (PA) in redox status biomarkers. We investigated the influence of PA on redox status and nitric oxide (NO) production/metabolism biomarkers in nonoverweight and overweight/obese prepubertal children. We performed a cross-sectional evaluation of 313 children aged 8-9 years (163 nonoverweight, 150 overweight/obese) followed since birth in a cohort study (Generation XXI, Porto, Portugal). Plasma total antioxidant status (P-TAS), plasma and urinary isoprostanes (P-Isop, U-Isop), urinary hydrogen peroxide (U-H2O2), myeloperoxidase (MPO) and plasma and urinary nitrates and nitrites (P-NOx, U-NOx) were assessed, as well as their association with variables of reported PA quantification (categories of PA frequency (>1x/week and ≤1x/week)and continuous PA index (obtained by the sum of points)) in a questionnaire with increasing ranks from sedentary to vigorous activity levels. U-NOx was significantly higher in children who presented higher PA index scores and higher PA frequency. Separately by BMI classes, U-NOx was significantly higher only in nonoverweight children who practiced PA more frequently (p = 0.037). In overweight/obese children, but not in nonoverweight, P-TAS was higher among children with higher PA frequency (p = 0.007). Homeostasis model assessment index (HOMA-IR) was significantly lower in more active overweight/obese children, but no differences were observed in nonoverweight children. In the fully adjusted multivariate linear regression models for P-TAS, in the overweight/obese group, children with higher PA frequency presented higher P-TAS. In the U-NOx models, U-NOx significantly increased with PA index, only in nonoverweight children. Our results provide additional evidence in support of a protective effect of physical activity, in nonoverweight by increasing NO bioavailability and in overweight/obese children by enhancing systemic antioxidant capacity and insulin sensitivity. These results highlight the importance of engaging in regular physical exercise, particularly among overweight/obese children, in which a positive association between oxidant status and cardiometabolic risk markers has been described.

Myocardial Injury Biomarkers in Newborns with Congenital Heart Disease.

BACKGROUND: Troponin I, myoglobin, and creatine kinase-MB mass (CK-MB) are biomarkers of cardiomyocyte injury widely used in the management of adult patients. The role of these biomarkers in newborns is still not established. The purpose of this study was to evaluate the value of cardiac injury biomarkers in newborns with congenital heart disease. METHODS: From August 2012 to January 2014, 34 newborns with a prenatal diagnosis of congenital heart disease were admitted consecutively to a neonatal intensive care unit. As controls, 20 healthy newborns were recruited. Plasma levels of cardiac biomarkers (troponin I, myoglobin, and CK-MB) were evaluated, and echocardiography was performed to evaluate cardiac function on D 1. Patients were followed during the first 28 days of life and, according to outcome, categorized as surgical or conservative treatment group. RESULTS: Median (P25-75) levels of CK-MB were higher in patients who underwent cardiac surgery in the neonatal period [7.35 (4.90-13.40) ng/mL] than in patients who were discharged home without surgery [4.2 (2.60-5.90) ng/mL; p = 0.032]. A CK-MB cutoff of ≥ 4.6 ng/mL showed sensitivity of 87.5% and specificity of 63.6%. Troponin I and myoglobin levels were not significantly different between conservative and surgical treatment groups. CK-MB levels correlated with the tissue Doppler image of the mitral valve lateral annulus peak early/late diastolic velocity ratio (ρ = -0.480, p = 0.018). CONCLUSION: CK-MB levels during the first hours of life were higher in newborns that needed neonatal cardiac surgery, and these levels may be an indicator of myocardial diastolic function.

Evaluation of prenatal risk factors for prediction of outcome in right heart lesions: CVP score in fetal right heart defects.

OBJECTIVE: To determine the prenatal variables predicting the risk of perinatal death in congenital right heart defects. METHODS: Retrospective analysis of 28 fetuses with right heart defects was performed. Logistic regression analyses were performed to obtain odds ratios (OR) for the relationship between the risk of death and echocardiographic parameters. The parameters that correlated with the outcome were incorporated in an attempt to devise a disease-specific cardiovascular profile score. RESULTS: Fetal echocardiograms (143) from 28 patients were analyzed. The cardiovascular profile score predicted the risk of death. A lower right ventricle (RV) pressure was associated with mortality (OR 0.959; 95% confidence intervals (CI) 0.940-0.978). Higher peak aortic velocity through the aortic valve (OR 0.104; 95% CI 0.020-0.529) was associated with a better outcome. These cardiac function parameters were incorporated in a modified disease-specific CVP Score. Patients with a mean modified cardiovascular profile score of ≤ 6 were over 3.7 times more likely to die than those with scores of 7-10. CONCLUSIONS: The original Cardiovascular Profile Score predicted the risk of death in right heart defects. The modified score was not validated as a good prediction tool by this study. Fetal RV pressure estimate and peak aortic velocity can be used as independent prognostic predictors.

Long term psychosocial outcomes of congenital heart disease (CHD) in adolescents and young adults.

BACKGROUND: Congenital heart disease (CHD) is a chronic illness with a high frequency in the worldwide population, and is normally diagnosed at birth or in uterus. Because of better conditions in diagnosis and early medical and surgical treatment, patients have survival rates of 90% and go further and further in life, facing different challenges in life cycle. In this study, we tested the effects of different demographic, clinical and psychosocial variables on the perception of quality of life (QOL), on psychosocial adjustment (PSA) and psychiatric morbidity (PM) of adolescents and young adults with CHD. OBJECTIVES: We aimed to evaluate QOL, PM and PSA of adolescents and young adults with CHD and to determine which variables (demographic, clinical, and psychosocial) play a role in buffering stress and promoting resilience and which ones have a detrimental effect. METHODS: The study enrolled 150 CHD patients (87 males and 63 females), 12 to 26 years (M: 17.45±3.373 years). The participants were interviewed regarding social support, family educational style, self-image, demographic information and physical limitations. They responded to questions in a standardized psychiatric interview (SADS-L) and completed self-reports questionnaires for assessment of QOL (WHOQOL-BREF) and PSA (YSR/ASR). RESULTS: We found an 18.7% lifetime prevalence of psychopathology in our participants (25.4% in females and 13.8% in males). 57.1% had retentions in school (M: 1.53±0.804 year). The perception of QOL of CHD patients is better compared to the Portuguese population in the Social Relationships, Environmental, Physical and General Dimensions. However, it is worse in complex forms of CHD, in cyanotic patients, in moderate-to-severe residual lesions, in patients submitted to surgery and in patients with physical limitations. All of these variables, except presence of cyanosis, are also associated to a worse PSA. Social Support is very important in improving QOL of patients in all dimensions as well as academic performance. CONCLUSIONS: Female patients and patients with poor academic performance and poor social support refer worse PSA and QOL.

Effects of diabetes mellitus, pressure-overload and their association on myocardial structure and function.

BACKGROUND: Structural and functional changes involved in cardiac injury induced by diabetes mellitus, pressure-overload, or both conditions were evaluated. METHODS: Pressure-overload was established by suprarenal aortic banding in rats. Six weeks later, diabetes was induced by streptozotocin (STZ, 65 mg/kg, intraperitoneally), resulting in four groups: SHAM, banded (BA), diabetic (DM), and diabetic-banded (DM-BA). On the 12th week, left ventricular (LV) structure and function were evaluated. LV function was assessed in vivo with pressure-volume catheters and in vitro by papillary muscles' performance at baseline and in response to isoprenaline (ISO, 10(-8) to 10(-5) M). RESULTS: Compared to SHAM, we observed a significant increase of type-B natriuretic peptide (BA = 370 +/- 110%; DM-BA = 580 +/- 210%), LV mass (BA = 36.8 +/- 3.6%; DM-BA = 32.1 +/- 3.1%), cardiomyocyte diameter (BA = 19.5 +/- 2.3%; DM = 14.3 +/- 1.9%; DM-BA = 11.4 +/- 2.0%), fibrosis (BA = 85 +/- 14%; DM = 145 +/- 28%; DM-BA = 155 +/- 14%), advanced glycation end-product (AGE) deposition (DM = 141 +/- 29%; DM-BA = 166 +/- 46%), contraction (tAT: DM = 13.7 +/- 2.4%; DM-BA = 26.3 +/- 7.1%); a delayed relaxation (tHR: DM = 13.8 +/- 2.6%; DM-BA = 25.5 +/- 9.2%) and a decrease of collagen type-I/type-III ratio (DM = -66.1 +/- 4.6%; DM-BA = -51.9 +/- 5.5). In SHAM animals, ISO (10(-5) M) increased 86.5 +/- 26.2% active tension, 105.3 +/- 20.2% dT/dt(max), and 166.8 +/- 29.9% dT/dt(min). Similar effects were observed in BA and DM animals, whereas in DM-BA these inotropic and lusitropic responses were blunted. Moreover, at a similar resting muscle length, ISO decreased passive tension by 12 +/- 3% in SHAM and 11 +/- 3% in BA, indicating an increase in myocardial distensibility, an effect that was absent in both diabetic groups. CONCLUSION: Long-standing pressure-overload increased LV mass, while diabetes promoted AGE and collagen deposition, which might explain the abolition of ISO-induced increased myocardial distensibility. Association of pressure-overload and diabetes completely blunted the inotropic and lusitropic responses to ISO, with no additional structural damages than in pressure-overload or diabetes alone.

N-terminal-pro-B type natriuretic peptide as a useful tool to evaluate pulmonary hypertension and cardiac function in CDH infants.

OBJECTIVE: In congenital diaphragmatic hernia (CDH) the severity of pulmonary hypertension (PH) is considered, by several authors, determinant of clinical outcome. Plasmatic N-terminal-pro-B type natriuretic peptide (NT-proBNP) might be useful in diagnosis and management of PH in newborns, although its interest in CDH infants remains to be defined. Early NT-proBNP levels were assessed in CDH infants and correlated with cardiovascular echocardiographic parameters. PATIENTS AND METHODS: 28 newborns, CDH and age-matched controls were enrolled in a prospective study. Clinical condition, NT-proBNP plasmatic levels, echo parameters of PH and biventricular function were assessed at 24 h after delivery as well as survival outcome. RESULTS: Estimated mean pulmonary pressure and NT-proBNP were significantly higher in CDH than control infants. NT-proBNP significantly correlated with estimated pulmonary artery pressure, right ventricular Tei index, and tricuspid E/A ratio. Additionally, we found that CDH infants with NT-proBNP >11,500 pg/ml experienced a worse prognosis. CONCLUSIONS: We demonstrated that PH is associated with NT-proBNP elevation and diastolic impairment in CDH infants. Early elevations in NT-proBNP levels seem to alert for a subset of CDH infants with worse prognosis.

Antenatal vitamin A administration attenuates lung hypoplasia by interfering with early instead of late determinants of lung underdevelopment in congenital diaphragmatic hernia.

BACKGROUND/PURPOSE: Early and late lung underdevelopment in congenital diaphragmatic hernia (CDH) is likely caused by nonmechanical (directly mediated by nitrofen) and mechanical (mediated by thoracic herniation) factors, respectively. The authors investigated if vitamin A enhances lung growth because of effects on both early and late determinants of lung hypoplasia. METHODS: Twenty-seven pregnant Wistar rats were exposed on embryonic day (E)9.5 to 100 mg of nitrofen or just olive oil. From nitrofen-exposed pregnant rats, 12 were treated at day 9.5 or 18.5 with 15,000 IU of vitamin A. Lungs were harvested at E18, E20, and E22, weighed, and analyzed for DNA and protein contents. Left and/or right lung hypoplasia was estimated by assessment of the ratios of lung to body weight and left to right lung weight. Fetuses were assigned to 5 experimental groups: baseline (exposed neither to nitrofen nor vitamin A), nitrofen (exposed to nitrofen without CDH), CDH (exposed to nitrofen with CDH), nitr+vitA (exposed to nitrofen without CDH and treated with vitamin A), and CDH+vitA (exposed to nitrofen with CDH and treated with vitamin A). RESULTS: Incidence of hernia was significantly reduced in fetuses treated with vitamin A. When vitamin A was administered at E9.5, the authors observed similar effect on lung hypoplasia measured through ratio of lung to body weight at E18 in the nitrofen and CDH groups (nitrofen 1.92% +/- 0.05%, CDH 1.92% +/- 0.04%), whereas lung hypoplasia was attenuated relative to baseline (2.45% +/- 0.05%) in 5% and 4% in nitrofen (nitr+vitA 2.05% +/- 0.03%) and CDH (CDH+vitA 2.08% +/- 0.04%) groups, respectively. At E20, lung hypoplasia was increased in CDH compared with nitrofen groups (nitrofen 2.52% +/- 0.1%, CDH 2.39% +/- 0.05%), whereas vitamin A attenuated lung hypoplasia, in relation to baseline (3.20% +/- 0.07%), 14% in both nitrofen-exposed groups (nitr+vitA 2.96% +/- 0.03%, CDH+vitA 2.83% +/- 0.03%). At E22, lung hypoplasia was significantly higher in CDH group than nitrofen group (nitrofen 2.13% +/- 0.06%, CDH 1.48% +/- 0.03%), whereas lung hypoplasia was attenuated in 9% of both nitrofen-exposed groups (nitr+vitA 2.35% +/- 0.06%, CDH+vitA 1.69% +/- 0.05%) in relation to baseline group (2.38% +/- 0.04%). Administration of vitamin A at E18.5 produced no significant effects on lung growth. CONCLUSIONS: The authors conclude from these results that antenatal administration of vitamin A attenuates lung hypoplasia in CDH by interfering with early determinants of lung underdevelopment. This finding may have clinical implications because prenatal diagnosis of human CDH commonly occurs after 16 weeks' gestation when late determinants of lung hypoplasia likely predominate.