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J C Areias

Publications and source records attributed to J C Areias.

At least 19 recordsLinked to original sources
PubMed2001

[Prognostic indexes derived from ventricular morphology in congenital diaphragmatic hernia induced by nitrofen].

BACKGROUND: Some indices derived from cardiac morphology have been proposed as prognostic factors in fetuses and newborns with congenital diaphragmatic hernia (CDH). These would be of interest in evaluating the risk of pulmonary hypoplasia and the need for surgery in the fetus. The aim of this study was to evaluate the heart-related indices in the nitrofen-induced CDH rat model. METHODS: At day 9 1/2 of gestation dated pregnant female Wistar rats received 100 mg of nitrofen. Fetuses were harvested at day 21 1/2 by laparotomy. The fetuses exposed to nitrofen without CDH were defined as the control group (n = 38) while the fetuses exposed to nitrofen with CDH were defined as the CDH group (n = 30). The hearts from both groups were weighed, processed for paraffin embedding and fragmented in serial 7 microns thick transverse sections. In the hearts without cardiac morphological defects the right and the left ventricular cavity volumes were estimated. These allowed calculation of cardioventricular and left-ventricular mass indices. RESULTS: In the fetuses without cardiac malformations, no significant difference was found regarding heart-to-body weight ratio, cardioventricular index or left ventricular mass between the study groups. CONCLUSION: In this model the presence of CDH was not associated with any alteration in cardiac dimension, in the absence of structural malformations. These results suggest that the indices derived from ventricular morphology should not be used to evaluate the prognosis in fetuses and newborns with CDH.

Animals↗
PubMed2001

Ebstein's anomaly in neonates.

Ebstein's anomaly is a rare congenital heart disease abnormality in which the tricuspid valve leaflets do not attach normally to the tricuspid valve annulus. The effective tricuspid valve orifice is displaced apically into the right ventricle (RV), near the junction of the inlet and the trabecular parts of the RV. The authors present a retrospective study of the patients with Ebstein's anomaly admitted to a neonatal intensive care unit, in the period between January 1993 and March 2000. There were ten patients, representing 0.24% of total neonates and 1.99% of total congenital heart disease admitted to the institution in the same period. Fifty per cent were male and only one case had prenatal diagnosis. Holosystolic murmur (100%) from tricuspid regurgitation and cyanosis (80%) were the most frequent clinical findings. Chest X-ray was abnormal in 90% of the neonates, with a "balloon-shaped" enlarged heart. The main electrocardiographic findings were right atrial enlargement (70%) and arrhythmias (40%). Apical displacement of the septal leaflet of the tricuspid valve, to a maximum of 20 mm, and leaflets tethering to underlying RV myocardium were found in all patients. Tricuspid valve regurgitation was found in 90% (severe form in four cases). An atrial intracardiac shunt, mostly right-to-left, was also found in 50%. Digoxin was used (40%) to restore sinus rhythm. Fifty per cent of the neonates received intravenous prostaglandins. Two patients required a surgical procedure. Two patients died in the neonatal period. During the follow-up period (range 0.3-74.6 months), only one episode of supraventricular tachycardia was recorded. At present seven patients are clinically stable, three of them on medication.

Child↗
PubMed2000

Heart-related indices in experimental diaphragmatic hernia.

BACKGROUND: Heart-related indices have been suggested as useful tools to evaluate left ventricular (LV) hypoplasia, which might predict the outcome of fetuses and infants with congenital diaphragmatic hernia (CDH). The current study analyzed the behavior of such indices in the nitrofen-induced CDH rat model. METHODS: Dated pregnant Wistar rats received at day 9.5 of gestation either a dose of 100 mg of nitrofen or just the vehicle. Body, lung, and heart weights were measured in 12 newborn rats not exposed to nitrofen (Ctrl group) and 68 animals exposed to nitrofen: 30 without CDH (non-CDH group) and 38 with left CDH (CDH group). Each heart was fragmented in 7-microm thick sections. Only hearts with no evidence of cardiac morphologic defects (CMD) were studied further to estimate right and left ventricular cavity volumes, septal, right, and left ventricular free wall masses. These parameters allowed the calculation of the cardio-ventricular (CVindex) and LV mass indices. The aorta-to-pulmonary artery ratio also was calculated. RESULTS: Excluding fetuses with CMD, the heart-to-body weight ratio was reduced significantly in animals exposed to nitrofen, whereas no significant differences were observed between non-CDH versus CDH groups. Although the left and right ventricular cavity volumes were both reduced significantly in nitrofen-treated rats, they were not changed significantly by the existence of CDH, and the calculated CVindex was similar in the 3 groups. Estimated septal and LV masses were reduced markedly in the nitrofen-treated animals and further reduced by the presence of CDH. However, when LV mass was normalized (LV mass index) the difference became restricted to the animals exposed to nitrofen but was not influenced by the presence of CDH. Finally, the aorta-to-pulmonary artery ratio was similar in all studied groups. CONCLUSIONS: The results of the current study suggest that, although nitrofen had been responsible by global heart hypoplasia, the presence of CDH was not associated with significant underdevelopment of the heart or of the LV in rat fetuses without CMD. Based on these results, we think that the evidence for prenatal counseling based on heart-related indices should be critically reconsidered.

Animals↗
PubMed2000

Anticipating twin-twin transfusion syndrome in monochorionic twin pregnancy. Is there a role for nuchal translucency and ductus venosus blood flow evaluation at 11-14 weeks?

Twin-twin transfusion syndrome is a major complication of monochorionic twin pregnancies. In foetuses from monochorionic twinning the presence of increased nuchal translucency thickness (NT) has been associated with an increased risk of developing this syndrome. One of the presumed mechanisms of increased NT is early cardiac failure, indirectly indicated by abnormal blood flow in the ductus venosus. We present eleven cases of monochorionic twin pregnancies in which nuchal translucency thickness and ductus venosus blood flow evaluation was performed at 11-14 weeks. In the two cases presenting with nuchal translucency discrepancy between the two foetuses along with anomalous ductus venosus blood flow in the foetus with increased nuchal translucency, twin-twin transfusion syndrome (TTTS) eventually developed. In none of the twins displaying no inter-twin difference in NT measurements and in those with discrepant NT but normal flow in both ductus venosus, was the progression to TTTS observed. In the two cases which developed TTTS, foetoscopic laser coagulation of the vascular anastomosis was successfully carried out at 18 weeks and normalisation of the venous return was registered. These findings suggest that the association of increased NT and abnormal flow in the ductus venosus in monochorionic twins may be an early manifestation of haemodynamic imbalance between the donor and the recipient eventually manifested as twin-twin transfusion syndrome. Further studies, however, are necessary to establish the potential role of the combination of NT and ductus venosus blood flow assessment as a screening method for TTTS.

Adult↗
PubMed2000

Prenatal diagnosis of congenital heart disease. Critical evaluation of a twelve-month experience.

INTRODUCTION: A retrospective study of fetal echocardiographies performed in the Ultrasound Unit of the Department of Obstetrics and Gynecology between January and December 1998 was carried out. MATERIAL AND METHODS: We performed 271 fetal echocardiographies (236 fetuses; 230 pregnant women). A triplex ultrasound machine was used with a 5 or 3.5 MHz transabdominal probe. RESULTS: The median maternal age was 31 years (17-44) and the median gestational age at the time of the first examination was 27 weeks (15-38). A hundred and thirty-two pregnant women (57.4%) were internal referrals and (98) 42.6% were referred by other hospitals. The most common indications for referral were maternal age > or = 35 years old (n = 48), gestational diabetes (n = 38), family history of congenital heart disease (n = 24) and insulin-dependent diabetes (n = 23). Accuracy of 32 echocardiographies was limited by technical difficulties. Out of 236 fetuses, 205 (86.9%) presented a normal scan, whereas 31 (13.1%) showed some abnormality: 22 structural cardiac defects; 5 rhythm anomalies and one with a mixed abnormality. In three cases a pericardial effusion was detected in the absence of any structural or rhythm anomaly and regressed spontaneously after birth. Three fetuses were referred prenatally for treatment to another center. Eight out of fifteen patients followed in the Pediatric Cardiology outpatient clinic were submitted to surgical treatment. In four cases the parents opted for termination of pregnancy and two neonatal deaths occurred. Four patients were lost for follow-up. DISCUSSION: Our study suggests that strict criteria for a referral of pregnant women to specialized fetal echocardiography are still missing. The median gestational age of 27 weeks at the time of the first examination was clearly out of the generally accepted recommended period (18-24 weeks). It is time to improve the collaboration between the different health professionals involved in the care of pregnant women in order to increase the sensitivity of screening for congenital heart disease.

Adult↗
PubMed1999

Cardiac defects in chromosomally normal fetuses with abnormal ductus venosus blood flow at 10-14 weeks.

OBJECTIVE: To assess a possible relationship between ductus venosus blood flow abnormalities and cardiac defects in chromosomally normal fetuses with increased nuchal translucency thickness at 10-14 weeks of gestation. METHODS: Ductus venosus Doppler ultrasound blood flow velocity waveforms were obtained at 10-14 weeks' gestation immediately before fetal karyotyping in 200 consecutive singleton pregnancies with increased nuchal translucency. Fetal echocardiography was subsequently carried out in those with normal fetal karyotype. RESULTS: Reverse or absent flow during atrial contraction was observed in 11 of the 142 chromosomally normal fetuses with increased nuchal translucency. Major defects of the heart and/or great arteries were present in seven of the 11 with abnormal ductal flow and increased nuchal translucency, but in none of the 131 with normal flow. CONCLUSION: These preliminary results suggest that abnormal ductus venosus blood flow in chromosomally normal fetuses with increased nuchal translucency identifies those with an underlying major cardiac defect.

Blood Flow Velocity↗
PubMed1999

[Aortic valvular stenosis: from infant to adult--Non-invasive evaluation and decision making through life].

Non-invasive diagnosis and management of congenital aortic valvular stenosis has been possible with more accuracy by using echocardiography and Doppler. Adequate diagnosis, even in fetal life, has been performed more easily. Moreover, the choice of surgical procedure or balloon valvuloplasty has been made by using Doppler echocardiography. Echo Doppler examination is also an excellent method for following the natural course of the disease. Other non-invasive procedures, such as electrocardiogram, exercise testing, X-ray and magnetic resonance, are useful, but also have some limitations.

Age Factors↗
PubMed1999

[Patent ductus arteriosus in neonatal intensive care].

OBJECTIVE: In this study we evaluated the prevalence of symptomatic patent ductus arteriosus (PDA) in newborns, admitted to a neonatal intensive care unit (NICU), as well as the clinical features and the outcome of medical or surgical treatment. METHODS: We carried out a retrospective medical chart review of 42 newborns admitted to an NICU between May 1996 and May 1998. Data regarding birth weight, sex, gestational age, prenatal corticotherapy and surfactant needs were gathered. Clinical evolution was assessed based on mechanical ventilation, morbidity and mortality. The therapeutic options and their results where analysed. RESULTS: Of the 1,195 newborns admitted to an NICU, 42 had symptomatic PDA. The prevalence was higher in newborns with a low birth weight. There was no significant difference regarding the administration of steroids prenatally in the newborns with PDA compared to the remaining newborns without PDA. Surfactant therapy, mechanical ventilation, bronchopulmonary dysplasia, necrotizing enterocolitis and intraventricular hemorrhage were found to be more frequent in patients with PDA, especially among those with a lower birth weight, with statistical significance for newborns weighing less than 2,500 g (p < 0.05). The therapy most frequently used was indomethacin, with a success rate of 22/23 (95.6%) and with two cases of acute renal failure as side effects. Only one infant required surgical ligation of PDA. Mortality was similar in both groups (PDA vs. no PDA). CONCLUSION: PDA was probably underdiagnosed in our NICU. Morbidity, but not mortality, was higher in newborns with symptomatic PDA. We conclude that treatment with indomethacin is preferred to surgical ligation as an initial approach in those infants. Our data show the importance of early screening with echocardiogram for "silent" PDA in low birth weight neonates.

Birth Weight↗
PubMed1999

[Absence of cardiac hypoplasia in an experimental model of congenital diaphragmatic hernia].

INTRODUCTION: Congenital diaphragmatic hernia (CDH) is a rare malformation in newborns. Amongst the various prenatal prognostic criteria, it is suggested that heart weight could be useful in evaluating the severity of lung hypoplasia. In this work we studied heart development in a rat model with nitrofen-induced CDH. MATERIAL AND METHODS: Pregnant female Wistar rats were treated on day 9 1/2 of gestation with 100 mg of nitrofen dissolved in 1 ml of olive oil. The control group was only treated with 1 ml of olive oil. The foetuses were delivered by caesarean section on day 21 1/2 of gestation. The weight of the foetuses was recorded. Under microscopy, the foetuses were dissected and the diaphragm was inspected. The wet weight of the heart and lung were recorded. The results are presented as a mean +/- standard deviation. A statistical analysis was made with the one-way ANOVA test on Ranks, and the Dunn test for post-test analysis. The statistical significance was set at a p < 0.05. RESULTS: The foetuses with CDH (n = 16) were lighter and had a smaller left lung/body weight ratio when compared with animals exposed to nitrofen without CDH (n = 18) and with controls (n = 12) (p < 0.05). The heart/ body weight ratio was smaller in foetuses exposed to nitrofen (p < 0.05), but we could not find any differences between nitrofen-treated treated foetuses with vs without CDH (n.s.). CONCLUSIONS: In spite of the lung hypoplasia, we could not demonstrate the presence of heart hypoplasia in rats with CDH when compared to nitrofen-treated foetuses without CDH.

Animals↗
PubMed1998

Anomalous fetal venous return associated with major chromosomopathies in the late first trimester of pregnancy.

We report three cases of increased nuchal translucency at 12-13 weeks of gestation in three fetuses with trisomies 13, 18 and 21. All three fetuses were associated with anomalous venous return evaluated by Doppler ultrasonography. Complete pathological examination was performed following termination in each case. We suggest that alterations in the venous compartment can be an early sign of poor outcome and should prompt a detailed search for cardiac defects early in gestation.

Adult↗
PubMed1998

Venous return and right ventricular diastolic function in ARED flow fetuses.

The absence or reversal of end-diastolic flow in the umbilical artery (UA) is widely accepted as an ominous sign of fetal compromise. However, in these high-risk pregnancies, the significance of sequentially appearing changes of the venous return is poorly established. Doppler blood flow waveforms were longitudinally assessed in the inferior vena cava (IVC), ductus venosus (DV), umbilical vein (UV) and tricuspid valve, along with the UA, middle cerebral artery and descending aorta. Thirty-two serial Doppler studies were performed in six fetuses with intrauterine growth-retardation (IUGR). In the cases of absent or reversed UA endodiastolic flow, changes in the venous return were found following the same sequence: presence of dicrote pulsations in the UV, increase of retrograde flow in the IVC and reduction or inversion of DV velocity during atrial contraction. Transtricuspid flow patterns changed from normal to a restrictive pattern of ventricular filling. There were two intrauterine deaths and one early neonatal death. Our preliminary results suggest that the evaluation of the venous compartment of hemodynamically disturbed preterms fetuses along with right ventricular filling appears to be a useful model for investigating the physiopathology of fetal deterioration and, therefore, may yield indirect discriminatory signs of severe compromise.

Adult↗
PubMed1998

[Anomalous origin of the left pulmonary artery (Sling): a case report and review of the literature].

Anomalous left pulmonary artery (vascular sling) is a congenital anomaly in which the vascular structure arises either from the posterior surface of the right pulmonary artery, or from the main pulmonary artery and courses to the left lung between the posterior surface of the trachea and the anterior surface of the esophagus. It may cause compression on the tracheobronchial tree. It is a rare condition leading to death in the first months of life, if it is not corrected. Its diagnosis is quite difficult because it usually presents non specific symptoms frequently associated to diffuse tracheal stenosis. The authors present a clinical case of a newborn with trisomy 21 who had a left pulmonary artery sling associated to tracheal stenosis and congenital heart disease (complete atrioventricular septal defect). They review the literature, particular in what concerns embryopathogenesis, the difficulties in establishing the diagnosis and the surgery which must be performed as soon as possible.

Aortopulmonary Septal Defect↗
PubMed1997

Ductus venosus revisited: a Doppler blood flow evaluation in the first trimester of pregnancy.

The functional role of the fetal ductus venosus (DV) is still poorly established. Few reports are available in the literature concerning assessment of fetal venous return during the late first trimester of pregnancy. Our objective was to determine the normal Doppler blood velocity waveform in the human fetal DV as early as 10-13 weeks gestation. Adopting strict methodological concerns, 61 Doppler blood flow evaluations of the DV considered technically acceptable were selected. Using transvaginal Doppler ultrasound, several DV haemodynamic parameters were assessed: peak systolic and diastolic velocities, time-averaged velocity, maximum velocity during atrial contraction, pulsatility index and fetal heart rate (FHR). Except for the FHR, no significant variations were observed for the above mentioned parameters during this period, and no correlation could be established between FHR and the different flow velocity parameters. Further knowledge about DV haemodynamics in the early phases of pregnancy may make a valuable contribution to the understanding of fetal venus return to the heart and cardiac function.

Blood Flow Velocity↗
PubMed1997

Increased fetal nuchal translucency: possible involvement of early cardiac failure.

The ultrasonographic measurement of nuchal translucency thickness at 10-13 weeks of gestation is accepted as an efficient method of screening for chromosomal abnormalities. However, the underlying mechanism producing increased nuchal translucency thickness is still poorly understood. The purpose of this study was to investigate the possible contribution of impaired cardiac function to such an increase, by studying the venous return in the ductus venosus, using Doppler ultrasound. In a total of 65 fetuses, nuchal translucency thickness was measured at 10-13 weeks of gestation by means of a transvaginal probe. Color-coded and pulsed Doppler ultrasound were also used to evaluate different hemodynamic parameters in the ductus venosus: maximum systolic and diastolic velocities, pulsatility index, lowest forward velocity during atrial contraction and fetal heart rate. Fetal nuchal translucency thickness of > or = 3 mm was found in 17 cases; in five of them there were chromosomal anomalies: four trisomy 21 and one trisomy 18. Of interest is the finding that in the five chromosomally abnormal fetuses with increased nuchal translucency thickness, the forward velocity during atrial contraction was consistently less than 2 cm/s (p < 0.001). This impairment of atrial contraction may well implicate cardiac failure and/or heart defects in the pathogenesis of increased nuchal translucency thickness in the first trimester of pregnancy. Furthermore, nuchal translucency may prove to be a sensitive marker for the early identification of fetal cardiac anomalies.

Blood Flow Velocity↗
PubMed1996

Effects of gradual volume loading on left ventricular diastolic function in dogs: implications for the optimisation of cardiac output.

BACKGROUND: Volume loading is commonly used to adjust preload and optimise cardiac output. It is difficult to monitor preload at the bedside because filling affects ventricular diastolic function and consequently end diastolic pressure, which is the variable used to monitor preload. OBJECTIVE: To assess the effects of gradual volume loading on the different components of left ventricular diastolic function---filling velocities, relaxation, and chamber compliance---to identify how excessive loading produces diastolic dysfunction. METHODS AND RESULTS: Eight mongrel dogs, anaesthetised and mechanically ventilated with both the chest and the pericardium closed, were studied during basal conditions (B), during gradual volume loading with physiological saline---5 ml/kg (VL5), 10 ml/kg (VL10), and 15 ml/kg (VL15)---and during infusion of isosorbide dinitrate (10 g/kg/min) started after the VL15 load was achieved. Dogs were monitored haemodynamically and by transthoracic Doppler echocardiography to assess peak modal velocities of the E and A waves, E/A ratios, and the deceleration time of the E wave. M mode recordings of aligned mitral and aortic valve motion were also obtained to calculate the isovolumic relaxation time. Effects of volume loading on ventricular diastolic function seemed to occur in two phases. Small and moderate volume loads (VL5 and VL10) promoted early ventricular filling, increasing E wave velocities, improving the mean (SD) E/A ratio from 1.95 (0.3) (B) to 2.0 (0.27) (VL5) and 2.6 (0.3) (VL10) (P < 0.00005), prolonging the E wave deceleration time, and only slightly increasing ventricular diastolic pressures. These changes suggest an improvement in ventricular compliance. Extreme volume loads (VL15) produced an abrupt reduction in early ventricular filling, which was transfered to late in diastole, by decreasing E wave velocity, by increasing A wave velocity, and by decreasing E/A ratio from 2.6 (0.3) (VL10) to 0.8 (0.05) (VL15) (P < 0.00005). The E wave deceleration time was shortened and left ventricular diastolic pressures were much increased, all suggesting a deterioration in chamber compliance. All these restrictive changes were promptly reversed by the perfusion of isosorbide dinitrate. The isovolumic relaxation time steadily increased with volume loading. CONCLUSIONS: Small and moderate volume loads improved ventricular diastolic function by promoting early ventricular filling and increasing ventricular compliance. Extreme volume loads promptly induced a diastolic restrictive pattern, transferring filling to the second part of diastole (increasing dependence on atrial contraction) and reducing ventricular compliance. These changes in ventricular diastolic function were independent of simultaneously measured haemodynamic systolic performance and were promptly reversed by isosorbide dinitrate, which after extreme loading promoted early filling, myocardial relaxation, and improved chamber compliance.

Animals↗