Disorders of laterality and heterotaxy in the foetus

Disorders of laterality and heterotaxy syndromes are rare diseases with an incidence of 1-1.5/10,000 live births. They are associated with numerous viscerocardiac anomalies and malformations. In particular, heterotaxy syndromes are associated with complex cardiac and extracardiac malformations that have an important impact on the prenatal and postnatal course. A prenatal differentiation between the 2 main variants of heterotaxy--left and right isomerism--is possible by assessment of cardiac rhythm, anomalies of caval veins and descending aorta and concomittant cardiac and extracardiac anomalies. An exact diagnosis is mandatory for adequate counselling of the parents and planning of postnatal care. Left isomerism has a high intrauterine mortality, caused by early atrioventricular block with subsequent cardiac failure and hydrops. In contrast, right isomerism has a high postnatal mortality due to the more complex type of cardiac defects and splenic disorders. The type of associated cardiac and extracardiac anomalies determines the postnatal morbidity and mortality. Polysplenia and asplenia may be associated with immunological disorders, that cannot be ruled out in the prenatal period, and further complicate the postnatal course.     

产前超声诊断在胎儿左侧异构中的应用

目的:探讨胎儿左侧异构的产前超声征象及其诊断价值。方法:回顾分析21例产前诊断为胎儿左侧异构的病例资料,对比总结其超声征象与随访结果。结果:21例左侧异构胎儿中,内脏心脏异位16例,先天性心脏病19例(伴心脏传导阻滞5例),下腔静脉离断伴奇静脉异常连接19例,其中两种及两种以上异常诊断胎儿左侧异构的敏感性为90.5%。染色体异常3例,18三体2例,13三体1例。18例终止妊娠,1例胎死宫内,2例存活。结论:产前超声诊断胎儿左侧异构是可行的,重要超声征象是内脏心脏异位、先天性心脏病伴或不伴心脏传导阻滞、下腔静脉离断伴奇静脉异常连接,出现上述两种或两种以上异常可提高该病的诊断敏感性。     

Situs ambiguo asociado a cardiopatía e interrupción de la vena cava inferior con continuidad de la ácigos

There is a spectrum of heterotaxic syndromes between normal organ distribution (situs solitus) and congenital conditions in which major organs are mirrored from their normal position (situs inversus). The two main modalities are left isomerism (with polysplenia) and right isomerism (with asplenia). Heterotaxic defects involve ciliary dyskinesia, hampering migration of embryonic organs and leading to malposition of thoracic and abdominal organs, complex cardiac defects, and other malformations. We present a case of prenatal echographic diagnosis of levocardia, with left-sided liver, asplenia, congenital heart disease, and interruption of the inferior vena cava with azygos continuation. Because of the malformations frequently associated with heterotaxy, the position of fetal organs should form part of routine ultrasonographic examination.     

Fetal complete heart block: antenatal diagnosis, significance and management

Complete heart block was diagnosed prenatally in 21 fetuses. Associated structural cardiac defects were present in 18 fetuses, in particular complete atrioventricular canal with atrial isomerism (5 cases), and 'corrected' transposition of the great arteries (4 cases). Maternal systemic lupus erythematosus was proved in only one case. In 11 fetuses, intra-uterine congestive heart failure with the signs of non-immune hydrops fetalis occurred. In all 11 fetuses, the hydrops was associated with a cardiac defect, in particular complete atrioventricular canal with atrial isomerism in 5 cases. A review of the literature confirms that only the association of complete heart block and cardiac malformation can cause intra-uterine congestive heart failure, whereas in the case of fetal complete heart block without cardiac malformation or with prenatally hemodynamically insignificant cardiac malformation, congestive heart failure is rare. Only 30% of newborns with complete heart block have associated cardiac malformations. In our series, however, 86% of the fetuses with complete heart block had cardiac malformations. The most important reason for this percentage discrepancy is that almost all fetuses with associated severe cardiac defects, in particular atrioventricular canal defects, develop heart failure which frequently results in prenatal death. Thus, fetal deaths are not included in pediatric statistics. Nevertheless, fetuses with isolated complete heart block generally do not develop heart failure and in almost all of the cases are born alive.     

Diagnóstico prenatal del arco aórtico derecho,importancia de los planos de Yagel. Nuestra experiencia,descripción de 2 casos

Right aortic arch, which belongs to a group of rare malformations, is an uncommon finding (incidence of 0.1%) and few cases of prenatal forms have been described in the literature. Nevertheless, it is not unusual to find these anomalies as the cause of respiratory or digestive disease (refractory to treatment) in adult patients and even as severe vascular processes with high morbidity and mortality. Its variants may cause compressive symptoms and be associated with heart defects (up to 90%) and/or 22q11 microdeletion (up to 46%). The 3 vessels and trachea view is essential for the prenatal diagnosis of right aortic arch. Detection of this condition must be considered an indication for foetal echocardiography, to distinguish its variants, and/or specific chromosome/genetic testing. Isolated right aortic arch is usually asymptomatic, although the outcome of right aortic arch associated with other abnormalities is poor.     

Evaluation of prenatal diagnosis of associated congenital heart diseases by fetal ultrasonographic examination in Europe

Ultrasound scans in the mid trimester of pregnancy are now a routine part of antenatal care in most European countries. With the assistance of Registries of Congenital Anomalies a study was undertaken in Europe. The objective of the study was to evaluate prenatal detection of congenital heart defects (CHD) by routine ultrasonographic examination of the fetus. All congenital malformations suspected prenatally and all congenital malformations, including chromosome anomalies, confirmed at birth were identified from the Congenital Malformation Registers, including 20 registers from the following European countries: Austria, Croatia, Denmark, France, Germany, Italy, Lithuania, Spain, Switzerland, The Netherlands, UK and Ukrainia. These registries follow the same methodology. The study period was 1996-1998, 709 030 births were covered, and 8126 cases with congenital malformations were registered. If more than one cardiac malformation was present the case was coded as complex cardiac malformation. CHD were subdivided into 'isolated' when only a cardiac malformation was present and 'associated' when at least one other major extra cardiac malformation was present. The associated CHD were subdivided into chromosomal, syndromic non-chromosomal and multiple. The study comprised 761 associated CHD including 282 cases with multiple malformations, 375 cases with chromosomal anomalies and 104 cases with non-chromosomal syndromes. The proportion of prenatal diagnosis of associated CHD varied in relation to the ultrasound screening policies from 17.9% in countries without routine screening (The Netherlands and Denmark) to 46.0% in countries with only one routine fetal scan and 55.6% in countries with two or three routine fetal scans. The prenatal detection rate of chromosomal anomalies was 40.3% (151/375 cases). This rate for recognized syndromes and multiply malformed with CHD was 51.9% (54/104 cases) and 48.6% (137/282 cases), respectively; 150/229 Down syndrome (65.8%) were livebirths. Concerning the syndromic cases, the detection rate of deletion 22q11, situs anomalies and VATER association was 44.4%, 64.7% and 46.6%, respectively. In conclusion, the present study shows large regional variations in the prenatal detection rate of CHD with the highest rates in European regions with three screening scans. Prenatal diagnosis of CHD is significantly higher if associated malformations are present. Cardiac defects affecting the size of the ventricles have the highest detection rate. Mean gestational age at discovery was 20-24 weeks for the majority of associated cardiac defects.     

产前超声诊断胎儿右房异构一例

本文报道产前超声诊断胎儿右房异构一例。孕妇孕24周产前超声检查发现胎儿左位心合并复杂心血管畸形(右心室双出口、房室间隔缺损、肺动脉发育不良、双侧上腔静脉、心下型完全型肺静脉异位引流)、胃泡位于腹腔右侧、中位肝、可疑无脾、腹主动脉与下腔静脉位于脊柱左侧、双侧支气管呈右侧支气管对称形态,综合考虑右房异构可能。引产后经尸体解剖证实脾脏发育不良、右房异构。右房异构常合并复杂心血管畸形,因此产前超声发现复杂心血管畸形时,应警惕右房异构的可能。右房异构病死率极高,产前诊断具有重要意义。     

Associated malformations in congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is a severe neonatal anomaly. The aim of this study was to evaluate the frequency and types of malformations associated with CDH. The outcome was compared with that in newborns with CDH alone. The study included 362 fetuses and newborns at a single national center for CDH. Associated malformations and chromosomal aberrations were noted prenatally and postnatally. The neonatal outcome was assessed relative to the use of extracorporeal membrane oxygenation (ECMO) and the mortality rate. At least one associated malformation was diagnosed in 143 cases (39.5%). Altogether, 272 associated malformations were found. Only 50 (18.4%) anomalies were diagnosed antenatally. In 62 (17.1%) cases, 102 major malformations were found along with CDH, with a prenatal detection rate of 35.3%. The associated malformations were very heterogeneous, but cardiovascular malformations were the most common. Newborns with major anomalies, chromosomal aberrations, or syndromes additional to CDH had a significantly lower survival rate than newborns with an isolated CDH. Associated malformations did not affect the rate of ECMO treatment. Associated malformations in CDH are frequent and heterogeneous, and diligent and experienced antenatal and postnatal care is important.     

Genetic components of perinatal morbidity and mortality.

The authors summarize the perinatal effects of the main genetic disorder groupings. Diseases of autosomal dominant inheritance are usually less severe and postnatal life is possible. Diseases of autosomal recessive inheritance are serious in most cases, causing severe symptoms in postnatal life. Diseases of X-linked recessive inheritance manifest themselves in male embryos and may be mild or serious; the more severe forms may influence the perinatal outcome. Diseases of X-linked dominant inheritance occur less frequently and manifest themselves in both sexes: in some cases the life expectancy is not favorable. Chromosomal anomalies, unbalanced rearrangements and autosomal trisomies may cause severe multiplex malformation syndromes and mental retardation. The diseases are serious in most cases and intrauterine mortality is high. Conversely, in cases of numerical differences of the sex chromosomes perinatal mortality does not increase remarkably, except in X-monosomy. Diseases of multifactorial origin lead to isolated malformations, but many civilization diseases originate from similar causes. In a few cases, severe diseases (i.e. congenital heart defects and neural tube defects) occur which may influence the outcome of the pregnancy. In terms of teratogenic effects, taking medication or undergoing X-ray examination or infections during early pregnancy indicates only a small risk in most cases. The authors emphasize that genetic centers significantly influence the perinatal outcome of pregnancies with their complex activity and their role in prenatal diagnostics.     

Prenatal diagnosis of congenital diaphragmatic hernia: an update

Congenital diaphragmatic hernia (CDH) has an incidence of approximately 1:4000 live births. Most frequently the diaphragmatic defect is a left and posterolateral (Bochdalek) one. Prenatal diagnosis is made at ultrasonography; the relevant sonographic features will be described in the paper. Cystic adenomatoid malformation of the lung (CAML), pulmonary sequestration, bronchogenic cysts, pulmonary hypoplasia/agenesia need to be considered in differential diagnosis. In some cases, diagnosis of CDH is not possible "in utero": in such cases, herniation of abdominal viscera into the thorax takes place presumably just at delivery through a small diaphragmatic defect. CDH may be associated with intrauterine growth retardation (IUGR), chromosomal abnormalities (3%) and/or other malformations (10-50%): such as Central Nervous System, digestive, cardiac and urogenital anomalies. Therefore, search of associated malformations and amniocentesis with analysis of fetal karyotype are mandatory, whenever a CDH is diagnosed. CDH is still at present characterised by a high mortality (reportedly, about 45%). Many prognostic factors have been correlated to postnatal outcome of CDH: some of them are valuable prenatally by ultrasonography. However, the role of sonography in the prediction of neonatal outcome is still controversial: in particular, although many ultrasonographic parameters have been proposed, prenatal evaluation of pulmonary hypoplasia (a crucial factor related to postnatal survival) has not proved to be very accurate so far. Nevertheless, it is undisputable that prenatal diagnosis itself represents a crucial prognostic factor for CDH, since it allows birth of the affected fetuses in 3d level Perinatologic Centres provided with a Neonatal Intensive Care Unit and Neonatal Surgery.     

Fehlbildungen des Thorax und des Abdomens

This article presents the spectrum of congenital intrathoracic and intra-abdominal malformations. In addition to a summary of epidemiological associations, prenatal observations of sonographic morphological and echocardiographic characteristics, pathogenetic hypotheses and consideration of possible associated syndromes or anomalies and comorbidities, prenatal and postnatal therapy options are also discussed.     

Fetal cardiac malposition: incidence and outcome of associated cardiac and extracardiac malformations

Cardiac malposition is a rare but important finding when detected on fetal ultrasound. The purpose of this study was to evaluate the incidence of fetal cardiac malposition, associated abnormalities, and clinical outcome in a tertiary-care medical center. Records of fetuses (1993 to 2006) with dextroposition, dextrocardia, mesocardia, ectopia cordis, or heterotaxy were reviewed. The presence of congenital heart disease (CHD), extracardiac anomalies, and outcome were noted. Cardiac malposition was present in 101 fetuses among a total of 3313 (3%) pregnancies. In 78 (78%) patients, the heart was positioned in the right hemithorax. Of those, 26 (33%) had dextrocardia (CHD = 21), and 52 (67%) had dextroposition (CHD = 14). Sixteen (16%) patients had mesocardia (CHD = 8), and 7 (7%) had ectopia cordis (CHD = 6). The majority (58%) of fetal cardiac malposition was caused by intrathoracic masses. Concomitant CHD occurred in 50%. Outcome was available in 97%. The perinatal and neonatal mortality rate was 30%; the elective termination rate was 4%. Patients with CHD had higher mortality rates. The highest mortality rates occurred in ectopia cordis and combined disease of diaphragmatic hernia and CHD.     

Prenatal diagnosis and management of congenital heart disease

Thirty-two fetuses were diagnosed as having congenital heart disease (CHD). The major indications for level II echocardiography other than suspected cardiac abnormalities were fetal malformations, nonimmune hydrops and cardiac arrhythmia. Only three patients had a previous history of fetal CHD. No false-abnormal diagnosis of severe CHD was made. Aortic arch anomalies represented the major diagnostic problem among the six correct but incomplete diagnoses. Sixty-one percent of the fetuses were growth retarded, thus confirming the severity of their CHD. Chromosomal anomalies and extracardiac malformations were associated in 19% and 44% of the fetuses, respectively. Obstetric management and fetal prognosis in cases of extracardiac malformations were greatly influenced by the diagnosis of CHD. The poorest perinatal outcome was associated with heart failure. The only intrauterine deaths occurred in that group, and only one neonate survived. The outcome was more favorable in neonates without other malformations or heart failure. Four of ten (40%) of those neonates survived, while the overall perinatal survival rate was 24%.     

Insight into the Genetic Relevance of Congenital Heart Defects

Congenital heart disease is the most common type of birth defect in the newborn??occurring in 1?% of neonates. In addition, cardiac defects account for nearly half of the neonatal deaths resulting from congenital malformations. Due to recent advances in spatial resolution of ultrasound machines and improvements in sonographic techniques, the clinician is increasingly able to detect cardiac anomalies in utero. At the same time, advances in cardiovascular surgery have improved the overall survival of the affected neonates. Due to the combination of advances in prenatal diagnosis and postnatal intervention, parents with fetuses affected by congenital cardiac defects have become the largest group who seek prenatal counseling on the risks of associated anomalies, risks for subsequent pregnancies, and the risks to the offspring of a successfully treated patient. Although most congenital heart defects are not familiarly clustered, genetic factors are still involved in most cases. In this review, we summarize recent evidence of chromosomal and genetic defects associated with congenital heart diseases to provide the optimal counseling and management for the parents with affected neonates.     

Etiology and prognosis of fetal ascites

OBJECTIVE: To examine the prenatal course and outcomes of neonates with isolated fetal ascites. METHODS: A retrospective analysis (from 1990 through 2000) was performed on 26 consecutive cases presenting with fetal ascites. A systematic diagnostic protocol which included fetal blood sampling for karyotyping, serology and serial ultrasound examinations to determine etiology was followed in all cases after diagnosis. Pregnancy outcome was assessed by a chart report or autopsy reports. RESULTS: The majority of cases were associated with fetal malformations (n = 11). Five fetuses had malformations with associated syndromes. Less commonly associated were intrauterine infections (n = 3), intestinal perforation (n = 2), genetic disorders (n = 2), neoplasm (n = 1) and growth retardation (n = 1). In only 1 case (4%) was the etiology idiopathic. Secondary generalized hydrops occurred only in 4 of 26 cases. Only 13 of 16 liveborn infants survived past the neonatal period and only 4 cases are doing well at childhood age without any sequelae. CONCLUSION: A wide range of etiologies were associated with isolated fetal ascites. Those with malformations had the worst pregnancy outcome. Prenatal diagnosis was made in 92% utilizing a systematic diagnostic workup. The diagnosis of idiopathic ascites has become rare due to the improvement in prenatal diagnosis.     

The prenatal diagnosis of cloacal dysgenesis sequence in six cases: can the termination of pregnancy always be the first choice?

OBJECTIVE: Cloacal dysgenesis sequence is a lethal malformation, which usually requires termination. In this study, our aim was to evaluate the prenatal and postnatal diagnostic features of cloacal dysgenesis sequence and review the management of the patients. MATERIAL AND METHODS: The data of six cases of cloacal dysgenesis sequences were collected from the ultrasonography and neonatal records. The findings were evaluated in prenatal and postnatal periods. Chromosomal analysis was performed in all the cases. The evaluation of primary and secondary malformations was done. Coexisting anomalies were searched for by radiology and histopathology. RESULTS: Malformations in six cases (two females and four males) were described. The absence of anal, genital, and urinary openings with intact perineum covered by smooth skin were common findings. These features were considered as primary malformations for cloacal dysgenesis sequence. Secondary anomalies (urinary and gastrointestinal system malformations, pulmonary hypoplasia, and other coexisting anomalies) were evaluated. CONCLUSION: The prenatal differential diagnosis of cloacal dysgenesis sequence from other urinary obstructive diseases was essential regarding fetal prognosis, prenatal, and neonatal management. The bladder outlet obstruction and pulmonary hypoplasia due to reduced amniotic fluid and/or kidney disease were considered prognostic factors for neonatal death. Termination of pregnancy is almost always recommended instead of intrauterine shunt procedures; but if we take into consideration one of our cases and a few reported cases who survived in the neonatal period, the prenatal management of these pregnancies needs to be reevaluated.     

Anomalies of the fetal venous system: a report of 26 cases and review of the literature

OBJECTIVE: To evaluate sonographic appearance, natural history, and neonatal outcome of fetal venous anomalies. METHODS: We performed an observational study, including all fetuses affected by abnormalities of the venous system diagnosed by ultrasound during the prenatal period. RESULTS: 26 fetuses were identified. Other malformations were present in 5 cases (19.2%), 1 fetus had trisomy 21, and 1 fetus had intrauterine growth retardation (IUGR). Twenty-five pregnancies ended in liveborn infants, and there was 1 case of unexplained intrauterine death in the fetus with IUGR affected by varix of the umbilical vein. CONCLUSIONS: Fetal venous anomalies are very rare and may be associated with fetal malformations or IUGR. Conservative management appears to be an adequate medical practice in the absence of other fetal problems, but in the presence of a varix of the umbilical vein, serial follow-up scans are needed to exclude the onset of hydrops or thrombosis of the varix.     

Hemifacial microsomia with spinal and rib anomalies: prenatal diagnosis and postmortem confirmation using 3-D computed tomography reconstruction

Hemifacial microsomia (OMIM164210) is a condition featuring unilateral ear anomalies and ocular epibulbar dermoids associated with unilateral underdevelopment of the craniofacial bony structures. Other associated anomalies have also been described, especially spinal malformations, and the term oculoauriculovertebral dysplasia spectrum (OVAS) was suggested to include the three predominant systems involved. Both genetic and environmental causes are implied in the pathogenesis of the syndrome, with a 3% recurrence rate according to reports of both vertical transmission and affected siblings. No specific gene was identified, albeit mutations in chromosome 10 and deficiencies of genes in the endothelin pathway in mice exhibited the same clinical features. We hereby describe the first case of prenatal diagnosis of spinal and rib malformations associated to hemifacial microsomia by means of 2-D and 3-D ultrasound in a 23-week fetus. The sonographic study depicted fetal scoliosis due to the presence of hemivertebrae, Sprengel's deformity of the left shoulder, ribs fusion, asymmetric ears with unilateral microtia, mandible unilateral hypoplasia as well as single umbilical artery and a 'golf ball' sign in the left ventricle of the heart. The diagnosis of OVAS was suggested and the family received proper genetic consultation. After termination of the pregnancy, the syndrome was confirmed by postmortem 3-D computed tomography study. In view of the grim outcome, prenatal death rate and high mortality and morbidity when three or more systems are involved, prenatal diagnosis and appropriate counseling are warranted.     

Hypoplastic left heart syndrome: prenatal diagnosis, clinical profile, and management

We diagnosed hypoplastic left heart syndrome, generally regarded as a lethal congenital heart defect, by fetal echocardiography in 20 pregnancies in the last 5 years. The clinical profile, management, and outcome of these pregnancies were reviewed. We found a 40% association of karyotype and extracardiac malformations. Elective abortion was performed in nine pregnancies. Two of seven live-born babies had early neonatal assessment and intervention as a result of in utero diagnosis and counseling. Prolonged survival was achieved in both infants. We conclude that prenatal diagnosis of the hypoplastic left heart syndrome necessitates complete evaluation of the fetus for associated genetic and extracardiac malformations. Prenatal diagnosis of this defect provides opportunities for in depth counseling of parents and obtaining informed consent for either postnatal intervention or nonintervention before the medical and emotional complexities associated with the neonatal intensive care setting are encountered.     

Congenital diaphragmatic hernia-associated cardiac dysfunction

There is increasing evidence that cardiac dysfunction is a key contributor to CDH pathophysiology. Dysfunction in both right and left ventricles is common in the early neonatal period, contributes to clinical disease severity, and is associated with adverse outcomes including death and ECMO use. Early and routine assessment of ventricular function and pulmonary artery pressure may guide individualized clinical decision-making, including use of pulmonary vasodilators, cardiotropes, ECMO, and timing of surgical repair. Minimizing cardiac dysfunction, whether by prenatal, postnatal or perinatal treatment strategies, may lead to improved outcome in CDH.