Ductus venosus: From the anatomy to fetal well being evaluation

O ducto venoso é a continuação da veia umbilical com a veia cava inferior, e ele, posteriormente ao nascimento, oblitera-se, formando o ligamento venoso. Por meio dele, o sangue rico em oxigênio, proveniente da veia umbilical, chega ao átrio direito e a partir daí, pelo forame oval, ganha o átrio esquerdo e a circulação sistêmica, favorecendo o fluxo para órgãos vitais como o cérebro fetal. Em obstetrícia, a ultra-sonografia Doppler tem sido amplamente utilizada para se examinar o sistema arterial fetal. Recentemente, mais atenção tem sido dispensada ao sistema venoso. O estudo das ondas de velocidade de fluxo venoso pode desempenhar um papel importante na avaliação do bem-estar fetal, uma vez que a velocimetria do ducto venoso pode estar alterada na vigência de patologias fetais. A característica mais interessante é a redução ou fluxo reverso durante a contração atrial, comumente encontrada em fetos com defeitos cardíacos congênitos, arritmias, transfusão fetofetal grave e restrição de crescimento intra-útero. Este texto tem a finalidade de revisar as características anatômicas e funcionais do ducto venoso fetal, bem como a importância de sua avaliação ultra-sonográfica pré-natal.The ductus venosus is a blood vessel unique to the fetal circulation which functions as a shunt between the umbilical vein and inferior vena cava. Well-oxygenated blood from the umbilical vein will course almost directly through the ductus venosus towards the foramen ovale and left heart favoring flow to vital organs as the fetal brain. It becomes functionally impervious to blood just after birth, in the majority of mammals. In obstetrics, Doppler ultrasound scan has largely been used to examine the fetal arterial system. Recently, more attention has been paid to the venous system. Assessment of venous flow velocity waveforms can play an important role in the surveillance of fetal well-being. The ductus venosus velocimetry can be altered in fetal diseases. The most striking feature is the reduced or reversed flow during atrial contraction commonly found in fetuses with congenital heart defects, arrhythmias, twin-twin transfusion syndrome and serious intrauterine growth restriction. This text includes a review of the anatomic and physiologic characteristics of fetal ductus venosus and the importance of its evaluation by prenatal ultrasound

Conjoined twins: an experience of a tertiary hospital in Southeast Brazil

OBJETIVO: analisar a ocorrência de gemelaridade conjugada em um hospital universitário de referência terciária em perinatologia durante 25 anos (janeiro de 1982 e janeiro de 2007) e descrever a separação bem sucedida de um dos pares. MÉTODOS: para este fim, utilizamos retrospectivamente o banco de dados do Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo, obtendo o número de pares de gêmeos conjugados, sua frequência, classificação, gênero, forma de resolução da gravidez, tentativa de separação cirúrgica, diagnóstico pré-natal e sobrevida. RESULTADOS: detectamos 14 pares de gêmeos conjugados (1/22.284 nascidos vivos e 1/90 pares de gêmeos nascidos vivos) nascidos neste período (seis masculinos, sete femininos e um com sexo indeterminado). O diagnóstico pré-natal foi realizado em todos os gêmeos, e os nascimentos ocorreram por cesariana. A separação só foi possível em um dos pares, que sobrevivem em ótimas condições de saúde após oito anos. Dos 13 restantes, dez morreram no mesmo dia do nascimento e três sobreviveram apenas alguns meses (menos de um ano). CONCLUSÃO: apesar de este estudo evidenciar um número anormalmente alto de gêmeos conjugados, trata-se de um fenômeno raro, de prognóstico perinatal reservado e dependente do compartilhamento de órgãos entre os gêmeos e malformações associadas, em especial relacionadas ao coração dos fetos. Devido ao mau prognóstico dos pares e do comprometimento reprodutivo materno pela necessidade de realização de cesariana com grandes incisões uterinas, propomos que, com base nestes números, seja solicitada a interrupção precoce destas gestações, como ocorre com outras doenças fetais incompatíveis com a sobrevida extrauterina. Desta forma, a confirmação diagnóstica e a resolução da gravidez de gêmeos conjugados deve ser realizada em centro de atendimento terciário tanto obstétrico quanto perinatal, e a autorização para a interrupção da gestação obtida por via judicial.PURPOSE: to analyze the occurrence of conjoined twins at a tertiary perinatology reference university hospital over a period of 25 years (January 1982 to January 2007) and to describe the successful separation of one of the pairs. METHODS: we consulted retrospectively the database of the University Hospital of the Medical School of Ribeirão Preto, University of São Paulo, Brazil, in order to determine the number of pairs of conjoined twins, their frequency, classification, gender, type of pregnancy resolution, attempted surgical separation, prenatal diagnosis and survival. RESULTS: we detected 14 pairs of conjoined twins (1/22,284 live births and 1/90 pairs of twin live births) born during this period (six males, seven females and one of indeterminate sex). The prenatal diagnosis was performed in all twins and all births were accomplished by cesarean section. The separation was possible in only one pair, which survives in excellent health conditions after eight years. Of the remaining 13, ten died on the day of birth and three survived only a few months (less than one year). CONCLUSION: Although our study revealed an abnormally high number of conjoined twins, this is a rare phenomenon, with a poor perinatal prognosis depending on the organs shared by the twins and associated malformations, especially those related to the fetal heart. Due to the poor prognosis of these pairs and to the maternal reproductive impairment caused by the need to perform body cesareans, we suggest that, based on these numbers, early interruption of these pregnancies be legally granted, as in the case of other diseases incompatible with fetal survival outside the uterus. Thus, the confirmation of a diagnosis of conjoined twins and the resolution of pregnancy should be performed at a tertiary obstetric and perinatal care center, and an authorization for the interruption of pregnancy should be obtained by judicial means

Raloxifene therapy does not affect uterine blood flow in postmenopausal women: a transvaginal Doppler study

AZEVEDO, George Dantas de et al. Raloxifene therapy does not affect uterine blood flow in postmenopausal women: a transvaginal Doppler study. Maturitas, Amsterdam, v.47, n.3, p.195-200, 2004Objective:To monitor the effects of raloxifene therapy on the uterus of postmenopausalwomen by transvaginal ultrasonography and color flow Doppler. Methods: Twenty-five healthy postmenopausal women were enrolled in this prospective longitudinal study performed at Department of Gynecology and Obstetrics, Faculty of Medicine of Ribeirão Preto. The patients were treated with raloxifene hydrochloride (60 mg per day) for 6 months. All were submitted to transvaginal ultrasound examination with color flow Doppler (ATL-HDI 3000 equipment) before the beginning and after 1, 3 and 6 months of treatment. Resistance index (RI) and pulsatility index (PI) of the uterine arteries were determined by the Doppler method, being considered as indicators of uterine perfusion. The following variables were analyzed: endometrial thickness, uterine volume, RI, and PI. Data were analyzed statistically by repeated-measures analysis of variance. Results: Before treatment, endometrial thickness was 3.38 ± 0.73 mm, and similar values were observed after 1, 3 and 6 months of treatment (3.04 ± 0.82; 3.3 ± 0.83; and 3.37 ± 0.79, respectively) (P > 0.05). No significant differences in uterine volume were observed between the pre- and post-treatment periods. Uterine artery perfusion as indicated by RI and PI measured by Doppler also showed no significant variation, with a high impedance flow being maintained throughout treatment. Conclusions: In the group studied here, raloxifene treatment at the dose of 60 mg per day for 6 months did not induce significant changes in endometrial thickness, uterine volume or uterine artery perfusion, confirming that short-term raloxifene treatment does not affect the uterus of postmenopausal wome

Protocol for detection, diagnosis and treatment of diabetes mellitus during pregnancy

The authors present the approach to pregnant woman for screening and diagnosis of gestational diabetes mellitus (GDM) and treatment of the diabetes mellitus during pregnancy, established as routine by the Sector of High Risk Pregnancy of the Department and Gynecology and Obstetric and Division of Endocrinology and Metabolism of Medicine School of Ribeirão Preto - University of São Paulo and it was assumed as a routine pre-natal evaluation for screening and diagnosis of GDM at Ribeirão Preto Health Secretary’s Office. This protocol was based on the recommendations of the World Health Organization and the American Diabetes Organization.Os autores apresentam a abordagem da paciente gestante, para rastreamento e diagnóstico do Diabetes mellitus Gestacional (DMG) e tratamento do Diabetes mellitus durante a gravidez, estabelecida como procedimento rotineiro pelo Setor de Gestação de Alto Risco do Departamento de Ginecologia e Obstetrícia e Divisão de Endocrinologia e Metabologia do Departamento de Clínica Médica da Faculdade de Medicina de Ribeirão Preto - Universidade de São Paulo e adotado na avaliação pré-natal da Secretaria Municipal de Saúde de Ribeirão Preto para rastreamento e diagnóstico do DMG. Este protocolo foi baseado nas recomendações da Organização Mundial da Saúde e American Diabetes Association

First trimester fetal echocardiography

Objective: The aims of this study were to assess the feasibility of performing a complete fetal echocardiographic study during the first trimester of pregnancy, to establish the best week to accomplish a complete evaluation, and to find a relationship between the diameters of the cardiac valves and gestational age. Methods: 46 fetuses with normal nuchal translucency and venous duct Doppler velocimetry were submitted to echocardiographic studies by the transvaginal approach between the 11 + 0 and 14 + 6 weeks of gestation. A complete echocardiographic evaluation was defined as an examination in which the three basic planes, four-chamber, longitudinal and short-axis views, were obtained. Results: The rates of complete echocardiography evaluation were 37, 85 and 100% at 11, 12 and 13-14 weeks, respectively. The longitudinal view was the easiest to obtain and the short-axis view was the most difficult one. The diameter of the cardiac valves was compared with the crown-rump length (CRL) and there was no statistically significant difference between either the diameters of the mitral and tricuspid or the aortic and pulmonary valves. A linear growth curve was constructed to demonstrate the diameter correlations. Conclusions: The study demonstrated the feasibility of a complete fetal echocardiographic evaluation by the transvaginal approach during the first trimester of gestation. The rate of a complete evaluation increased along the period and reached 100% when the CRL was 64 mm or 13 weeks of gestational age. There was a linear correlation between the cardiac valve diameters and the CRL revealing a relationship between the cardiac and fetal development. The absence of a statistically significant difference between the left and right valve dimensions possibly means that there is no predominance of right or left chambers during this period of evaluation. Copyright (C) 2007 S. Karger AG, Basel

Rastreamento e diagnóstico ecocardiográfico das arritmias e cardiopatias congênitas fetais Screening and echocardiographic diagnosis of arrhythmias and congenital heart diseases in the fetus

OBJETIVO: analisar os resultados obtidos em programa de rastreamento e diagnóstico de arritmias e cardiopatias congênitas centrado em uma unidade terciária e determinar a importância do diagnóstico precoce na evolução fetal e neonatal. MÉTODOS: foram analisados os resultados da avaliação cardíaca fetal efetuada em 1159 gestantes em dois níveis diferentes. Nível I: uso da ultra-sonografia morfológica com o objetivo de rastrear a presença de alteração cardíaca, sem estabelecer um diagnóstico diferencial. Nível II: por ecocardiograma fetal com o objetivo de diagnosticar as cardiopatias fetais existentes. Os resultados da detecção de arritmias bem como da avaliação das alterações estruturais foram comparados, sendo estabelecidas a sensibilidade e a especificidade para ambos os níveis no pré-natal, ao exame pós-natal ou à necropsia. A concordância entre ambos os níveis foi calculada pelo índice kappa. RESULTADOS: as arritmias detectadas no nível I foram confirmadas em todos os casos e não houve falso-negativos, sendo que em cinco pacientes houve necessidade de tratamento intra-útero. A detecção das alterações estruturais obtidas no nível I teve sensibilidade de 72% e especificidade de 98%, com 28% de falso-positivos. No nível II estes parâmetros foram, respectivamente, de 100 e 99%. De acordo com o coeficiente kappa de 57%, um grau de concordância de categoria moderada foi observado entre ambos os níveis. Das cardiopatias congênitas da nossa série 51% necessitaram intervenção farmacológica ou invasiva no período neonatal. CONCLUSÃO: o estudo ultra-sonográfico obstétrico é fundamental no rastreamento das alterações cardíacas fetais. O ecocardiograma fetal apresentou alto índice de sensibilidade e especificidade no diagnóstico das arritmias e cardiopatias congênitas, possibilitando o tratamento precoce das alterações graves.<br>PURPOSE: to analyze the results of a screening and diagnostic program of arrhythmias and congenital heart disease in a reference hospital and the relevance of early diagnosis in the fetal and neonate evolution. METHODS: cardiac evaluation of 1159 fetuses was done in two different levels. Level I: by morphological ultrasound examination with the objective to detect the existence of either arrhythmias or structural cardiac malformations. Level II: by fetal echocardiography to establish the differential diagnosis. The results of level I in the arrhythmia group were compared with those of level II, and in the group with malformations the results of both levels were confronted with the neonate echocardiogram or necropsy. The kappa index was calculated to evaluate the concordance between the two levels. RESULTS: all detected arrhythmias in level I were confirmed in level II, there were no false negative cases and five patients with severe arrhythmia required pharmacological therapy. The diagnosis of structural malformation by level I had sensitivity of 72% and specificity of 98% and there were 28% of false-positive cases. In level II, the sensitivity and specificity of the diagnosis of congenital heart disease were 100 and 99%, respectively. The kappa index was 57% and indicated a moderate degree of concordance between the two levels. Fifty-one percent of the fetuses with diagnosis of cardiac malformations required pharmacological or invasive intervention immediately after birth. CONCLUSION: morphological ultrasound examination is a important tool in the screening of arrhythmias and congenital heart defects during fetal life. The sensitivity and specificity of the fetal echocardiogram were very high and the early diagnosis made it possible to treat the fetus with severe cardiac disease either during pregnancy or immediately after birth