Intraoperative transesophageal echocardiogram using an intracardiac ultrasound catheter in a congenital heart surgery: a case report.

Transesophageal echocardiography (TEE) during cardiac surgery is a routine procedure. The use of pediatric TEE probes is limited in small infants weighing less than 5 kg. Recent reports have shown the safety of monoplane intravascular ultrasound catheters in transesophageal echocardiograms. This report describes the case of a newborn with total anomalous pulmonary venous return who underwent cardiac surgery. A pre- and postbypass TEE examination was performed, with successful visualization of the cardiac anatomy and function and no complications.

Nitric oxide and prostaglandins - important players in endothelin-1 induced myocardial distensibility.

This study investigated whether endothelin (ET)-1-induced increase in myocardial distensibility is preserved in heart failure (HF) and whether it is modulated by nitric oxide (NO) and prostaglandins. New Zealand white rabbits were treated with doxorubicin (1 mg/kg, intravenously twice a week for 8 weeks, DOX-HF group) or saline (control group). Effects of ET-1 (0.1, 1, 10 nM) were tested in papillary muscles from the DOX-HF group and a control group in the presence of: i) intact endocardial endothelium (EE); ii) damaged EE; iii) N(G)-nitro-L-arginine (L-NNA; NO synthase inhibitor), and iv) indomethacin (INDO; cyclooxygenase inhibitor). In the presence of an intact EE, ET-1 promoted concentration-dependent positive inotropic and lusitropic effects that were maintained after damaging the EE, in the presence of L-NNA or INDO and in the DOX-HF Group. ET-1 reduced resting tension at the end of the isometric twitch (increased diastolic distensibility) by 3.2+/-1.3 %, 6.0+/-1.6 % and 8.8+/-2.7 % (at 0.1, 1 and 10 nM, respectively), in muscles with intact EE, effect that was completely abolished after damaging EE, in the presence of L-NNA or INDO or in the DOX-HF Group. This study demonstrated that the increase in myocardial distensibility induced by ET-1 is absent in HF and is dependent of NO and prostaglandin release.

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.

Congenital heart malformations associated with dilated cardiomyopathy.

From June 1977 to February 1986 we studied 31 children with dilated cardiomyopathy. Seven patients (22%) aged 8 months to 3 years had associated congenital cardiac lesions--tetralogy of Fallot (3), coarctation of the aorta (2), ventricular septal defect (1) and Ebstein's malformation (1). The diagnosis was confirmed by hemodynamic and angiographic studies in 5 patients and by autopsy in 2. Although different congenital lesions were present, all 7 patients had congestive heart failure, flattening of T-waves or ST-segment depression on the electrocardiogram and significant decrease in the left ventricular shortening fraction as judged by echo. We conclude that the incidence of dilated cardiomyopathy associated with congenital heart malformations is high in our pediatric population. The clinical status of patients appears to be more dependent on the improvement of dilated cardiomyopathy and less dependent upon the underlying congenital heart malformations.

Common arterial trunk associated with absence of one atrioventricular connexion.

An unusual case of common arterial trunk is described. The right pulmonary artery is supplied by the ascending trunk and the left pulmonary artery arises via an arterial duct from the left brachiocephalic trunk. Although common arterial trunk can exist with any atrioventricular connexion, the absence of one atrioventricular connexion (tricuspid atresia) is the other rarity of this case.

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.

Monitoring of cardiac-extracardiac haemodynamics and automated fetal heart rate preceding intrauterine death.

A severely growth-retarded fetus was monitored longitudinally for haemodynamic profiles and automated cardiotocogram analysis in the 30 days preceding death. Initially a pattern of hypoxia and moderately deteriorated cardiac function was detected. Later on, signs of progressive heart failure developed, in conjunction with deteriorating fetal heart rate patterns.

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.

[Aortic valvular stenosis: from infant to adult--Non-invasive evaluation and decision making through life]. / Estenose valvular aórtica: da criança ao adulto avaliação não-invasiva e estratégia de decisão ao longo da vida.

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.

[Patent ductus arteriosus in neonatal intensive care]. / Canal arterial patente em cuidados intensivos neonatais.

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.

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.

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.

[Anomalous origin of the left pulmonary artery (Sling): a case report and review of the literature]. / Origem anómala da artéria pulmonar esquerda (Sling): caso clínico e revisão da literatura.

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.

[Absence of cardiac hypoplasia in an experimental model of congenital diaphragmatic hernia]. / Evidência experimental da ausência de hipoplasia cardíaca num modelo de hérnia diafragmática congénita.

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.

[Prognostic indexes derived from ventricular morphology in congenital diaphragmatic hernia induced by nitrofen]. / Indices de prognóstico derivados da morfologia ventricular na hérnia diafragmática congénita induzida pelo nitrofeno.

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.

[Transvaginal endosonography and Doppler study in embryo-fetal hemodynamic assessment in the first pregnancy trimester]. / Endo-sonografia e Doppler transvaginal na avaliação hemodinâmica embrio-fetal no 1.o trimestre da gravidez.

Transvaginal endosonography is now currently used in obstetrics and gynecology practice and seems a promising tool for essential studies on first trimester pregnancy. High-resolution and duplex/color Doppler in vaginal probes have brought to light new chances for early investigations on embryonic-fetal haemodynamics. We report our experience in this field, together with a review of the literature, giving an overview on embryonic-fetal cardiovascular haemodynamics studied by this approach. Blood flow patterns of intracardiac flows as extra-cardiac circulation during first trimester pregnancy are reported.

[Acute pericarditis in childhood. The 9-year experience of a tertiary referral center]. / Pericardite aguda na criança. Experiencia de 9 anos de um centro de referencia terciário.

Sixteen children, aged 7 months to 12 years, with acute pericarditis, admitted between 1985 and 1993 to a tertiary referral centre were analyzed retrospectively for their presentation, etiology, work-up, management and prognosis. It was found that most of the presenting signs were not specific and were often related to associated diseases such as respiratory tract infections. In 50% of the cases a cause was not found, the others had viral infections (12.5%), tuberculosis (12.5%), Haemophilus influenzae infection (6.25%), Toxocara canis infection (6.25%) and collagen diseases (12.5%). In eight cases non-steroidal anti-inflammatory drugs associated with steroids were given, 7 patients received non-steroidal anti-inflammatory drugs and 1 steroids. The mean follow-up time was 3 years (1 to 5). Six patients had one or more relapses. Five of the 6 patients with relapses were in the group which received steroids. The two patients with tuberculosis underwent pericardiectomy. One child died due to complex heart disease and the remaining 15 were cured. It was concluded that in pericarditis an extensive work-up may not reveal the major etiologies and that long term prognosis is good.