Prenatal diagnosis of cardiosplenic syndromes: a 10-year experience

Can Fetal Heterotaxy Syndrome Be Diagnosed Through Prenatal Ultrasound in the First Trimester (GA 11+0-13+6 Weeks)?

OBJECTIVE

To investigate the value of prenatal ultrasonography in the diagnosis and classification of fetal heterotaxy syndrome (HS) in the first trimester (gestational age 11+0-13+6 weeks).

METHODS

A retrospective analysis of data from 31 HS fetuses prenatally diagnosed with HS. Diagnoses were confirmed by follow-up prenatal ultrasound and in some cases postnatal ultrasound or autopsy. Data were collected on ultrasound characteristics of left atrial isomerism (LAI) and right atrial isomerism (RAI) in the first trimester, follow up ultrasounds, pregnancies outcomes, and postnatal ultrasound or autopsy findings, if available.

RESULTS

In total, 23cases of HS were diagnosed in the first trimester, and 8 cases were missed during the GA 11+0-13+6 weeks ultrasound. The sensitivity, specificity, false positive rate, false negative rate, positive predictive value, and negative predictive value of prenatal ultrasound examination for fetal HS were 74.19%, 100%, 0, 25.80%, 100%, and 99.98%, respectively. The main and common manifestations of fetal HS included abnormal positioning of the stomach and heart and positioning of the stomach and umbilical vein (UV) on different sides, combined with complete atrioventricular septal defect (AVSD), double outlet of the right ventricle (DORV) and other CHDs. Compared with RAI, fetuses with LAI in the first trimester of pregnancy were more prone to bradycardia and ductus venous (DV) a-wave inversion (p < 0.05). Among the 31 HS cases, only 6 pregnancies were continued, resulting in one neonatal death and five liveborns with a good prognosis.

CONCLUSION

Ultrasound performed during GA 11+0-13+6 weeks can be an effective tool for diagnosing fetal HS, particularly when significant cardiovascular anomalies are present. However, fetal LAI without complex intracardiac malformations is more likely to be missed in diagnosis during the first trimester. Most cases of HS diagnosed in early pregnancy are associated with major intracardiac anomalies and result in termination of pregnancies.

Early and long-term outcomes following cardiac surgery for patients with heterotaxy syndrome

Objective

Heterotaxy syndrome is a complex multisystem abnormality historically associated with high morbidity and mortality. We sought to evaluate the early and long-term outcomes after cardiac surgery in heterotaxy syndrome.

Methods

This is a single-center retrospective review of patients with heterotaxy syndrome undergoing single-ventricle palliation or primary or staged biventricular repair from 1998 to 2018. Patients were stratified by single ventricle versus biventricular physiology, and the severity of atrioventricular valve regurgitation. Demographics, anatomic characteristics, and early and late outcomes, including the length of stay, mortality, and surgical or catheter reinterventions, were analyzed.

Results

Among 250 patients, 150 (60%) underwent biventricular repair. In-hospital mortality was 7.6% (n = 19). Median follow-up was 5.2 (range, 0-16) years. Among survivors to discharge, mortality was 19% (n = 44) and reintervention was 52% (n = 120). Patients with moderate/severe atrioventricular valve regurgitation were older (32 vs 16 months, P = .02), were more likely to experience adverse events during their index surgical admission (72% vs 46%, P < .001), and had longer in-hospital length of stay (20 vs 12 days, P = .009). Among patients with moderate to severe atrioventricular valve regurgitation, single-ventricle palliation is associated with a greater risk of unplanned reintervention compared with patients undergoing biventricular repair (hazard ratio, 2.13; CI, 1.10-4.12; P = .025).

Conclusions

There was no significant difference in early or late outcomes in single-ventricle versus biventricular repair strategies in heterotaxy. In the subgroup of patients with moderate/severe atrioventricular valve regurgitation, patients who underwent single-ventricle palliation were 2.5 times more likely to need a late reintervention compared with those undergoing biventricular repair.

Clinical profile, prenatal detection and predictors of outcome of heterotaxy syndromes in Western Australia

Background

Heterotaxy syndromes encompass left and right atrial isomerism (LAI and RAI respectively) and are associated with variable cardiac and non-cardiac anomalies which greatly influence outcomes. RAI is usually associated with complex congenital heart disease (CHD), early surgical intervention and increased mortality. LAI is less commonly associated with complex CHD but can be associated with heart block. The objective of this study was to review the clinical features and outcomes of patients with heterotaxy syndromes in Western Australia (WA).

Methods

A retrospective review was performed of live born patients diagnosed with heterotaxy from 2003 to 2022 in a statewide tertiary cardiac service, representing all cases in WA with a view to compare the outcomes between LAI and RAI at our centre.

Results

30 patients (53% male) were diagnosed with heterotaxy; 16 (53%) with LAI and 14 (47%) with RAI. Overall incidence was 0.48 per 10,000 live births over the defined period. RAI patients were significantly more likely to have an antenatal diagnosis (81.8% versus LAI 28.6%, p = 0.03). Overall, 5-year survival was 56% for RAI and 87% for LAI. No deaths occurred after the first 12 months of life with a median follow-up of 65 months (IQR 114.8). RAI was associated with asplenia (91%), atrioventricular septal defect (91%) and a functionally univentricular circulation (71%). LAI was associated with polysplenia (100%) and complete heart block in 3 patients (19%). Surgical pathways included repair of anomalous pulmonary venous return (45%), Blalock Taussig shunt (60%), bidirectional cavopulmonary connection (50%) and Fontan completion (30%).

Conclusions

Patients with RAI suffer high mortality and early surgical intervention, with few making it to Fontan completion. By comparison patients with LAI have less morbidity and mortality. The management of heterotaxy continues to be challenging due to widely associated cardiac and extracardiac manifestations.

A gene-based association test of interactions for maternal-fetal genotypes identifies genes associated with nonsyndromic congenital heart defects

The risk of congenital heart defects (CHDs) may be influenced by maternal genes, fetal genes, and their interactions. Existing methods commonly test the effects of maternal and fetal variants one-at-a-time and may have reduced statistical power to detect genetic variants with low minor allele frequencies. In this article, we propose a gene-based association test of interactions for maternal-fetal genotypes (GATI-MFG) using a case-mother and control-mother design. GATI-MFG can integrate the effects of multiple variants within a gene or genomic region and evaluate the joint effect of maternal and fetal genotypes while allowing for their interactions. In simulation studies, GATI-MFG had improved statistical power over alternative methods, such as the single-variant test and functional data analysis (FDA) under various disease scenarios. We further applied GATI-MFG to a two-phase genome-wide association study of CHDs for the testing of both common variants and rare variants using 947 CHD case mother-infant pairs and 1306 control mother-infant pairs from the National Birth Defects Prevention Study (NBDPS). After Bonferroni adjustment for 23,035 genes, two genes on chromosome 17, TMEM107 (p = 1.64e-06) and CTC1 (p = 2.0e-06), were identified for significant association with CHD in common variants analysis. Gene TMEM107 regulates ciliogenesis and ciliary protein composition and was found to be associated with heterotaxy. Gene CTC1 plays an essential role in protecting telomeres from degradation, which was suggested to be associated with cardiogenesis. Overall, GATI-MFG outperformed the single-variant test and FDA in the simulations, and the results of application to NBDPS samples are consistent with existing literature supporting the association of TMEM107 and CTC1 with CHDs.

Difficulty in the Diagnosis of Biliary Atresia Splenic Malformation Syndrome In Utero

The fetus of a 30-year-old pregnant Japanese woman was diagnosed with absence of inferior vena cava (IVC) and azygos continuation of interrupted IVC without cardiac anomalies at 34 weeks of gestation, and a healthy male neonate weighing 2,910 g was delivered at 37 weeks of gestation. On day 42 after birth, direct bilirubin predominant hyperbilirubinemia and high serum gamma-GTP levels were detected. Computed tomography revealed the presence of a lobulated and accessory spleen, and laparotomy demonstrated type III biliary atresia (BA), confirming the final diagnosis of BA splenic malformation (BASM) syndrome. In retrospect, non-visualization of the gallbladder was missed in utero. The combination of the absence of IVC and BA without cardiac anomalies is far less likely to occur in left isomerism. Although BA remains difficult to detect in utero, special attention should be paid to cases of BA associated with findings of left isomerism, including the absence of IVC, to enable early diagnosis and treatment of BASM.

Double outlet right ventricle

This review article addresses the history, morphology, anatomy, medical management, and different surgical options for patients with double outlet right ventricle.

Four-section approach of fetal congenital heart disease at 11-13+6 weeks

Objective

The objective of the study is to explore the value of the four-section approach in detecting fetal heart defects in the first trimester (11-13+6 weeks), analyze the reasons for the inconsistency between the results of ultrasound examination in the first trimester and subsequent verification, and describe the most common abnormal flow patterns of four sections.

Materials and methods

Between June 2019 and June 2021, a prenatal four-section approach (upper abdominal transverse section, four-chamber section, three vessel-trachea section, and bilateral subclavian artery section) with verification results in early pregnancy was analyzed.

Results

In total, 9,533 fetuses were included. Finally, 176 fetuses with congenital heart disease (CHD), containing 34 types, were identified. The total detection rate of cardiac abnormalities was 1.85%. 102 cases were accurately diagnosed by ultrasonography during early pregnancy. A total of 74 fetuses who had inconsistent results between fetal cardiac ultrasound and verification in early pregnancy were reported, of which the cases of 22 fetuses were inconsistent due to disease evolution and progression and the cases of 52 fetuses were inconsistent due to missed diagnosis and misdiagnosis. The sensitivity, specificity, positive predictive value, and negative predictive value of the four-section approach were 67.05%, 99.96%, 96.58%, and 99.33%, respectively. In this study, a total of 30 abnormal ultrasonic imaging patterns in four sections were summarized.

Conclusion

We confirmed that the four-section approach in early pregnancy has a good diagnostic efficacy for fetal CHD. Intrauterine evolution of the fetal heart, missed diagnosis, and misdiagnosis are the reasons for the inconsistency between the results of early pregnancy ultrasound and subsequent verification. This study also presents the abnormal imaging patterns of four scan sections of CHD in early pregnancy, which are instructive for the rapid identification and diagnosis of CHD in the first trimester.

Characterization of ultrasound and postnatal pathology in fetuses with heterotaxy syndrome

Background

To explore the diagnostic clues and abnormality spectrum of heterotaxy syndrome by prenatal ultrasonography and postnatal verification.

Methods

The prenatal ultrasonic data of 88 heterotaxy syndrome fetuses were analyzed retrospectively as left isomerism (LI) and right isomerism (RI). Prenatal ultrasound compared with the anatomical casting of the fetal body after labor induction, and the confirmatory postnatal diagnosis after delivery.

Results

Fetal LI showed typical malformations of gastric vesicles on different sides from the heart, absence of hepatic segment of the inferior vena cava (IVC), abdominal aorta (AO) parallel with the azygos vein (AV), bilateral left bronchus, bilateral left atrial appendages, and polysplenia; intracardiac malformations of AV septal defects (AVSD), single atrium (SA), left ventricular outflow tract obstruction (LVOTO), and double-outlet right ventricle (DORV); and cardiac conduction abnormalities of sinus bradycardia and AV blockage. Fetal RI reported typical malformations of gastric vesicles on different sides from the heart, juxtaposition of the IVC with AO, anomalous pulmonary venous connection (APVC), asplenia, and bilateral right atrial appendages; intracardiac malformations of AVSD, SA, single ventricle, pulmonary atresia and stenosis, and DORV. The postnatal verification revealed 3 malformations misdiagnoses and 4 malformations missed diagnoses in LI fetuses and 10 misdiagnoses and 8 missed diagnoses in RI fetuses.

Conclusions

The proposed five-step prenatal ultrasonography has an important diagnostic value for the identification and classification of heterotaxy syndrome. The different sides of gastric vesicles and cardiac apex are important diagnostic clues for heterotaxy syndrome, featuring disconnected or hypoplastic IVC, typical complex cardiac malformation, and atrioventricular block in fetal LI, and shown APVC, juxtaposition of IVC and AO, and intracardiac malformations such as AVSD, DORV, and LVOTO in fetal RI.

Pre-procedural imaging and atrial tachycardia ablation in a patient with complex congenital heart disease

Atrial tachycardias (AT) are common cardiac arrhythmia disorder for congenital heart disease (CHD). The anatomic substrate that surgical suture lines, scar tissue, or prosthetic material may cause pre-existing atrial conduction abnormalities which leads to the underlying mechanism of reentrant ATs. Radiofrequency Catheter ablation (RFCA) is used in the treatment of atrial tachycardia in CHD patients. However venous system abnormalities may complicate the procedure. We report that ablation of a case with atrial tachycardia with challenging anatomy (persistent left superior vena cava draining into the left atrium, coronary sinus agenesis, inferior vena cava (IVC) agenesis, azygos system drained to the superior vena cava, and repaired ventricular septal defect). This case report discusses the key points of access to cardiac chambers and mapping in very rare challenging anatomy.

Heterotaxy Syndrome with Increased Nuchal Translucency and Normal Karyotype Associated with Complex Systemic Venous Return. Ultrasound Diagnosis with Autopsy Correlation

Background: Prenatal ultrasound (US) detection of heterotaxy syndrome can be challenging, especially in identifying cardiovascular and associated anomalies. We present a new case of heterotaxy syndrome with anomalous systemic venous return (ASVR) fully displayed at autopsy. Case report: Left heterotaxy syndrome was diagnosed in a 19 weeks' of gestation fetus with right-sided stomach. The heart showed both ventricles with left morphology, a large ventricular septal defect, persistent left superior vena cava draining into the coronary sinus, ASVR with interrupted inferior vena cava (IVC) and azygous continuation. Autopsy dissection further identified the azygous draining into the left lower pulmonary vein (LLPV). Prenatal a-CGH on villous sampling showed 22q13.1 microduplication inherited from the father, not contributory to the phenotype. Conclusion/discussion: Heterotaxy syndrome requires US accuracy for anomaly identification, as they allow legal termination of pregnancy. Our case is unusual as IVC drained into the azygous vein and then into the LLPV.

Prenatal diagnosis of hepatic interruption of the inferior vena cava with azygos/hemiazygos continuation without structural heart defects: A case series

OBJECTIVES

To describe fetal spectrum and echocardiographic characteristics of interrupted inferior vena cava (IIVC) with azygos/hemiazygous continuation without other structural heart defects and to evaluate its association with visceral heterotaxy and isomerism, extracardiac and genetic anomalies, and to review neonatal outcome.

METHODS

This was a retrospective study of 14 fetuses with a confirmed diagnosis of IIVC with normal intracardiac anatomy. The following variables were collected; indication for referral, gestational age at diagnosis; associated isomerism and visceral heterotaxy, heart rhythm, genetic and extracardiac abnormalities, and fetal/neonatal outcome.

RESULTS

Among 36 fetuses with IIVC, 14 cases (38.8%) had normal intracardiac anatomy. These IIVC cases correspond to 0.19% (14/7250) of all fetal cardiac examinations, and to 1.5% (14/922) of all cardiac abnormalities. Six patients had visceral abnormalities. Atrial appendage morphology was clearly depicted in three fetuses, both appendages were left. One fetus had bradyarrhythmia revealing atrial ectopic rhythm. Six fetuses did not have any concomitant cardiac or visceral abnormalities, therefore regarded as isolated. All babies were delivered at term with a good prognosis.

CONCLUSION

Our study has shown that almost half of the IIVC cases without intracardiac structural anomalies displayed other findings of isomerism while the other half was isolated benign vascular variant. Therefore, prenatal diagnosis of IIVC should prompt a comprehensive evaluation for cardiac, situs, and visceral anomalies. The outcome is favorable.

A Rare Case of Polysplenia Syndrome Associated with Severe Cardiac Malformations and Congenital Alveolar Dysplasia in a One-Month-Old Infant: A Complete Macroscopic and Histopathologic Study

Polysplenia syndrome represents a type of left atrial isomerism characterized by multiple small spleens, often associated with cardiac malformations and with situs ambiguus of the abdominal organs. The case presented is of a one-month-old male infant, weighing approximately 3000 g, born at the County Clinical Emergency Hospital of Sibiu, who was hospitalized from birth until death. The patient suffered cardio-respiratory arrest due to severe hypoxia and septicemia on the background of a series of complex cardiac malformations associated with congenital abdominal organ anomalies. Examination of the body revealed a common atrium with complete atrioventricular canal defect, left ventricular hypertrophy, right ventricle hypoplasia, truncus arteriosus, superior vena cava duplication, bilobation of the lungs, situs ambiguous of the abdominal organs with right-sided stomach, a midline liver, gall bladder agenesis, multiple right-sided spleens and complete inversion of the intestines and pancreas. Histopathology concluded that the patient suffered cardiac lesions consistent with infantile lactic acidosis, as well as pulmonary modifications suggesting congenital alveolar dysplasia and altered hepatic architecture compatible with fibrosis.

Heterotaxy syndrome: Prenatal diagnosis, concomitant malformations and outcomes

OBJECTIVE

The aim of this study is to define cardiac and extracardiac malformations in fetuses with heterotaxy syndrome and to determine perinatal and childhood prognosis.

METHODS

In this retrospective study, fetuses diagnosed with heterotaxy syndrome on antenatal ultrasonography in a tertiary center between January 2014 and January 2021 were analyzed. Fetuses with heterotaxy syndrome were grouped as right atrial isomerism (RAI) and left atrial isomerism (LAI).

RESULTS

A total of 62 fetuses, 32 (51.6%) with RAI and 30 (48.4%) with LAI, were included in the study. Extracardiac anomaly was detected in 25% of fetuses with RAI and 44% of fetuses with LAI (p = 0.13). Patients with univentricular repair had a higher childhood mortality than patients with biventricular repair (p = 0.031). The presence of conotruncal anomaly was an independent factor affecting mortality (HR = 5.09, CI 95% 1.09-23.71, p = 0.039).

CONCLUSION

Hydrops fetalis, univentricular physiology and conotruncal anomalies are associated with poor outcomes in heterotaxy syndrome. The severity of the cardiac malformation is the main determinant of the outcomes. The presence of extracardiac malformations is associated with increased morbidity and mortality.

Fetal Ultrasonic Evaluation of Bronchial Morphology in Fetuses with Isomerism

OBJECTIVE

The aim of the study was to evaluate whether fetal ultrasound could determine bronchial isomerism and distinguish left isomerism from right isomerism.

METHODS

We identified 110 healthy fetuses and 28 fetuses with isomerism. The outer angle between the tracheal midline and the inner margin of the bronchus is measured. The bronchial angles and the ratio of left/right bronchial angle were used to differentiate bronchial morphology and confirm the presence of bronchial isomerism in pathological cases.

RESULTS

The normal angles of the left and right bronchi were 146.98° (95% CI, 145.15-147.81°) and 167.37° (95% CI, 166.30-168.44°), separately. The cutoff bronchial angle of 156.5° was used to distinguish left bronchus from right bronchus. The bronchial isomerism could be identified in all pathological cases by autopsy and bronchial-atrial concordance occurred in 27 pathological cases (96.4%). In 21 pathological cases, the bilateral bronchial angle was <156.5 versus >156.5 differentiated left from right isomerism, respectively. The ratio of the left/right bronchial angle of >0.935 identified 92.9% (26/28) of all pathological cases, with a sensitivity of 89.7%.

CONCLUSIONS

Fetal ultrasound can detect the bronchial morphology and the presence of bronchial isomerism in fetuses with isomerism according to bronchial angles and the ratio of left/right bronchial angle.

Heterotaxy syndrome with complex congenital heart disease, facial palsy, and asplenia: A rare newborn finding

Heterotaxy syndrome is associated with asplenia/polysplenia and complex congenital heart disease. Facial palsy in heterotaxy is very rare. The management is still challenging with a poor prognosis. Proper counseling to the family about the disease course, treatment modalities, and outcomes is essential.

Predicting Cardiac Anatomy, Physiology, and Surgical Management Based on Fetal Echocardiography in Heterotaxy Syndrome

OBJECTIVE

 Heterotaxy syndrome (HS) is often associated with complex congenital heart disease (CHD). While fetal echocardiography (FE) permits accurate prenatal identification of most CHD, the high level of disease complexity in HS may pose challenges in predicting postnatal findings and outcomes. This study aimed to define the accuracy of FE in predicting postnatal anatomy, physiology, and surgical management of CHD in the setting of HS.

STUDY DESIGN

 Retrospective single-center cohort study including all patients with a prenatal diagnosis of HS from 2003 to 2018. Anatomic diagnoses from FE reports were compared with postnatal echocardiogram, catheterization, and operative reports. Prenatal predictions were compared with postnatal outcomes with a focus on ductal dependence, time to first intervention (immediate, neonatal period, 1-6 months, or older than 6 months), and surgical approach (single or biventricular).

RESULTS

 There were 102 pregnancies with fetal HS resulting in 21 terminations, 5 fetal losses, and 76 live births. Of the live births, 55 had significant CHD and available postnatal data for review. Among this group, survival to 1 year was 62% and was no different comparing single versus biventricular surgical approach. FE diagnostic accuracy varied by anatomic feature and was the lowest for diagnosis of venous anatomy. Determination of postnatal care was most accurate for predicting single versus biventricular surgical approach (91%), followed by ductal dependence (75%). Accuracy for predicting time to first intervention was the lowest at 69%. The most common reason for an incorrect prediction was difficulty in assessing the severity of pulmonary stenosis.

CONCLUSION

 FE permits accurate predictions regarding surgical approach. Characterizing systemic and pulmonary veins is challenging, as is predicting ductal dependence and time to first intervention. These data suggest that despite the high diagnostic accuracy of CHD in HS, a circumspect approach may be reasonable with regard to predicting some anatomic details and postnatal management decisions.

KEY POINTS

· In HS, FE was most accurate for intracardiac anatomy.. · Diagnostic accuracy of venous anatomy was less reliable.. · Predicting surgical approach (single ventricle vs. biventricular) was highly accurate.. · Predicting ductal dependence and time-to-intervention were more challenging in some instances..

Right atrial isomerism diagnosed by STIC-HD live flow and autopsy: A case report

RATIONALE

Right atrial isomerism (RAI) is one of the most severe forms of congenital heart disease. This case of RAI was so complex that it incorporated 7 heart defects. It can be challenging to display the spatial relationship between different anatomical structures using conventional two-dimensional and color ultrasound (2D-Doppler imaging); therefore, we used spatio-temporal image correlation (STIC) and high definition live flow imaging technology to vividly display this case of RAI in a stereoscopic mode.

PATIENT CONCERNS

A 24-year-old woman was referred to our tertiary center at 24 weeks of gestation. The woman had difficult conceiving. Once pregnant, she was opposed to abortion, even if there was a possibility of deformity.

DIAGNOSIS

The fetus presented with an atrioventricular septal defect, persistent left superior vena cava, supra-cardiac total anomalous pulmonary venous connection (TAPVC), double outlet right ventricle, right ductus arteriosus, right aortic arch (RAA) with mirror image branching, and aortic arch dysplasia.

INTERVENTIONS

After consulting a pediatric cardiologist, the woman requested an abortion and consented to an autopsy.

OUTCOMES

Autopsy supported the echocardiographic findings.

LESSONS

Accurate diagnosis of RAI is essential for clinical and parent decision making. 2D-Doppler imaging combined with STIC-HD live flow can be used to visualize the spatial morphology of blood vessels, including the cardiac chambers and great vessels of the fetal heart, and smaller peripheral vessels.

The heterotaxy syndrome: associated congenital heart defects and management

Heterotaxy syndrome (HS) constitutes a spectrum of anomalies arising from embryological errors that result in abnormalities of lateralization involving thoraco-abdominal viscera and culminate in loss of normal asymmetric arrangement of these organs. Besides the unique challenges involved in planning and execution of surgical procedures aimed at correction or palliation of these anomalies, they have the potential to cause profound physiological and immunological consequences in the individual patient due to their cardiac and extra-cardiac manifestations. This article aims to review the literature on this rare and extraordinary subset of developmental anomalies with the intention of familiarizing the reader on the modes of presentation, manifestations, and the variations thereof while dealing with this anomaly. In our institutional experience with HS, 75 consecutive patients were seen between January 2011 and September 2018. Of these, 48 (64%) were confirmed to have isomerism of right atrial appendages (IRAA) and the rest had isomerism of left atrial appendages (ILAA). The cardiac and extra-cardiac manifestations of these patients were listed out. Fifty-four patients (34 with IRAA and 20 with ILAA) underwent 83 surgical procedures. While 49 patients were palliated on the univentricular pathway, 5 underwent biventricular repair. The in-hospital mortality was 7 (13%) in both groups combined (5 for patients with IRAA and 2 for ILAA). In conclusion, the surgical management of HS is associated with satisfactory outcomes in current era.

Novel insights into the genetic landscape of congenital heart disease with systems genetics

We recently conducted a large-scale mouse mutagenesis screen and uncovered a central role for cilia in the pathogenesis of congenital heart disease (CHD). Though our screen was phenotype based, most of the genes recovered were cilia-related, including genes encoding proteins important for ciliogenesis, cilia-transduced cell signaling, and vesicular trafficking. Also unexpected, many of the cilia related genes recovered are known direct protein-protein interactors, even though each gene was recovered independently in unrelated mouse lines. These findings suggest a cilia-based protein-protein interactome network may provide the context for congenital heart disease pathogenesis. This could explain the incomplete penetrance and variable expressivity of human CHD, and account for its complex non-Mendelian etiology. Supporting these findings in mice, a preponderance of cilia and cilia related cell signaling genes were observed among de novo pathogenic variants identified in a CHD patient cohort. Further clinical relevance unfolded with the observation of a high prevalence of respiratory cilia dysfunction in CHD patients. This was associated with increased postsurgical respiratory complications. Together these findings highlight the importance of cilia in CHD pathogenesis and suggest possible clinical translation with instituting pulmonary therapy to improve outcome for CHD patients undergoing congenital cardiac surgeries.

Left atrial isomerism associated with aneurysmal enlargement of right atrial appendage: A case report with literature review

We present a prenatally diagnosed case of heterotaxy syndrome (HS) in which left atrial isomerism (LAI) was associated with an aneurysmal enlargement of the right atrial appendage (RAA). Although LAI is usually associated with complex cardiac and extracardiac anomalies, the association of LAI and right atrial appendage aneurysm (RAAA) is exceptional. Congenital RAAA itself is an idiopathic, very rare cardiac anomaly characterized by the enlargement of the appendage in the absence of any other cardiac or extra-cardiac defect. The prognosis of the heterotaxy is poor with associated major cardiac malformations and even cases with minor cardiac anomalies are at risk postnatally for complications like biliary atresia, intestinal rotational abnormalities, and immune disorders. In this case, the prenatal diagnosis of the isomerism was mainly based on the abnormalities of caval veins. Although no typical complex cardiac anomaly was present, the HS was associated with biliary atresia, polysplenia, and malrotation of the gut. Associated RAAA further imposed an additional risk of complications such as tachyarrhythmias, thromboembolic events, and aneurysmal rupture.

Characteristics and outcomes of fetuses with laterality defects are the current outcomes better? A single center study

Objective: To analyze the more recent outcomes of fetuses with different laterality defects.Material and methods: Out of 1508 fetuses with congenital heart disease (CHD) diagnosed by echocardiography between January 1995 and December 2015, 94 (6.3%) presented abnormal visceroatrial situs: 42 till December 2002 (group 1, analyzed retrospectively) and 52 since then until December 2015 (group 2, analyzed prospectively). Twenty-one had left isomerism (Lisom), 22 right isomerism (Risom), 16 situs inversus- dextrocardia (SVI-dx), 5 situs inversus- levocardia (SVI-levo), and 30 situs solitus-dextrocardia (SSol-dx).Results: Seventy-six cases (81%) had CHD, more frequently complex atrioventricular defect. Eighteen cases showed normal heart: half of subgroups SVI-dx and SVI-levo, a third of SSol-dx. Postoperative mortality in continuing pregnancy in group 2 was 43.7 versus 40% in group 1, lower in SVs-dx (0 versus 50%) and Lisom (33.3 versus 66.7%), worse in Risom (71.4 versus 25%). Total mortality in group 2 was 48.3 versus 55% in group 1, better in Ssol-dx (37.5 versus 50%) and in Lisom (27.4 versus 71.4%). In isolated forms all but one case are alive.Conclusions: Our fetal cases presented a relevant mortality in both periods. The outcomes were slightly better in a more recent era in SSol and Lisom.What is known about this topic?Out of laterality defects, the heterotaxies (i.e. left and right isomerism) are known to be associated to a relevant mortality in fetal and neonatal cases.Heterotaxies have a variable position of the heart, but some authors evaluated only those with dextrocardia in their studies on different laterality defects.Controversial data are presented in the literature for the outcomes of fetuses with laterality defects. Many large studies analyzed the data of a very long time period in which it is opinable to compare the results of the treatment, because of a recent improved management and surgical techniques.What does this study add?Our study presents an experience of a single center with cases of different types of laterality defects observed during a routine fetal echocardiography, not only heterotaxies.The knowledge of different laterality defects and of their characteristics (association with cardiac and extracardiac anomalies or with normal heart) is useful for the prenatal counseling.We compare the postoperative and total mortality in more recent period (since 2003) with respect to the previous era (1995-2002).

Pre natal evaluation of heterotaxy syndrome by fetal echocardiography and correlating with autopsy

Introduction

Heterotaxy syndrome/ isomerism is characterized by an abnormal symmetry of the viscera that are normally dissimilar due to abnormal lateralization of thoracic and abdominal viscera and is frequently associated with complex cardiac anomalies. Isomerism may be of right or left.

Materials and methods

This article describes the morphological characteristics of heterotaxy and suggests an approach in evaluating the spectrum of abnormalities associated with this syndrome. This study is based on 12 cases diagnosed on antenatal ultrasound as heterotaxy syndrome. Results of the examinations were re-evaluated and compared by fetal autopsy.

Result

Based on the following echocardiographic criteria, a diagnosis of left isomerism was made if there was viscerocardiac heterotaxy associated with an interruption of inferior vena cava or with bilateral finger-like atrial appendages or if it was associated with heart block. If there was evidence of viscerocardiac heterotaxy with complex cardiac anomalies then it was diagnosed as right atrial isomerism or visceral heterotaxy syndrome. We diagnosed 6/12 as left isomerism and rest of the cases as right isomerism/visceral heterotaxy syndrome. In Autopsy we evaluated visceral situs and morphology of the lungs and the main bronchi, the state of the liver, spleen, bowel, and the precise anatomy of the heart and confirmed 4/12 as left isomerism 4/12 as right isomerism and two cases as visceral heterotaxy syndrome (VHS). Rest of the two cases were included in the study despite missing autopsy data, as the combination of abnormal situs with interrupted inferior vena cava, and cardiac malformation allowed a diagnosis of left isomerism with high probability.

Conclusion

In this study, we aimed to find common features of heterotaxy syndrome on prenatal ultrasound as well as on fetal autopsy. This syndrome should be accurately diagnosed in the prenatal period in order to allow appropriate counseling of parents.

Prenatal Findings in Left Atrial Isomerism and an Overview of Heterotaxy Syndrome

Heterotaxy syndrome is a rare, complex disorder involving structural cardiac defects in combination with symmetrical development of abdominal viscera that are normally asymmetrical organs. The vast assortment of cardiac manifestations with accompanying abdominal visceral variations determines the prognosis of heterotaxy syndrome. This case study provides an example of the management of this disease, which is unique to the patient. This is a case report of heterotaxy syndrome diagnosed in utero at 29 weeks and 4 days.

A case of prenatally detected left isomerism and hemiazygos continuation of inferior vena cava

Heterotaxy syndromes are defined as the disorders that involve abnormal arrangement of viscera. We present a case of prenatally diagnosed left isomerism in a 30-year-old primigravida woman referred to our hospital for complex cardiac abnormality. Sonographic findings included heart block, unbalanced atrioventricular septal defect, interruption of the inferior vena cava with hemiazygos continuation, double superior vena cava, a right-sided stomach, and biliary atresia. The hemiazygos vein drained into the right atrium by the persistent left superior vena cava. This type of inferior vena cava interruption and continuation is rarely reported in prenatally detected cases of left isomerism. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 45:430-433, 2017.

Predictors of poor outcome among children with heterotaxy syndrome: a retrospective review

Objective

To determine predictors of poor outcome in patients with heterotaxy syndrome.

Methods

A retrospective review of children with heterotaxy syndrome, in a single tertiary paediatric cardiology centre, was conducted between 1 January 1997 and 1 January 2014 to determine predictors of poor outcome. Poor outcome was defined as death, cardiac transplantation or New York Heart Association (NYHA) functional class III or IV.

Results

There were 35 patients diagnosed with heterotaxy syndrome, 17 of whom were diagnosed antenatally. 22 patients had right atrial isomerism and 13 had left atrial isomerism. The median age of postnatal diagnosis was 2.5 days old (1 day to 19 months). 12 patients had a poor outcome; 6 patients died, 1 underwent cardiac transplantation and 5 had an NYHA functional class of >III. 5 patients had a biventricular repair and the remaining 30 had a univentricular repair. Type of atrial isomerism, univentricular or biventricular anatomy, severity of atrioventricular valve regurgitation or ventricular dysfunction, obstructed pulmonary venous return, occurrence of arrhythmia and presence of pulmonary atresia did not predict poor outcome. Fetal diagnosis also did not confer a survival advantage. The median duration of follow-up in this cohort was 65 months (2 days to 16.8 years).

Conclusions

Survival for patients with heterotaxy syndrome was 83% over a median follow-up of 65 months. 34% of patients had a poor outcome. None of the variables studied were predictive of death, transplantation or NYHA classification III or IV.

Utility of fetal magnetic resonance imaging in assessing the fetus with cardiac malposition

OBJECTIVE

Abnormal cardiac axis and/or malposition prompts evaluation of congenital heart disease; however, etiology may be difficult to clarify using obstetrical ultrasound or fetal echocardiography (echo) alone. We aimed to use fetal magnetic resonance imaging (MRI) as a complementary tool to identify causes of cardiac malposition.

METHODS

Review of fetuses diagnosed with cardiac malposition by fetal ultrasound and echo was performed. Etiology was classified as either because of heterotaxy syndrome or extracardiac masses. Reclassification was then performed with fetal MRI findings. Results were compared with postnatal diagnoses.

RESULTS

Forty-two fetuses were identified as having abnormal cardiac axis and/or malposition. Twenty three of 42 cases (55%) had extracardiac anomalies, while 19 (45%) were because of heterotaxy. Twelve of 42 (29%) cases were reassigned by fetal MRI (five in heterotaxy group and seven in the lung anomaly group). Four cases (33%) had both cardiac disease and extracardiac masses, not previously recognized. Fetal MRI clarified heterotaxy subtype or removed heterotaxy diagnosis in five (26%) patients. Fetal MRI findings were confirmed in 8 of these 12 cases postnatally.

CONCLUSION

Fetal MRI is a useful complementary tool to define etiology of cardiac malposition in complex cases for informative prenatal counseling and planning. © 2016 John Wiley & Sons, Ltd.

Extracardiac anomalies in prenatally diagnosed heterotaxy syndrome

OBJECTIVE

To assess the incidence and impact of extracardiac anomalies on the prognosis of fetuses with heterotaxy syndrome.

METHODS

All fetuses diagnosed with heterotaxy syndrome by three experienced examiners over a period of 14 years (1999-2013) were reviewed retrospectively.

RESULTS

In total, 165 fetuses with heterotaxy syndrome were diagnosed in the study period. One hundred and fifty (90.9%) had cardiac defects; extracardiac anomalies that did not involve the spleen were present in 26/165 (15.8%) cases. Of the total study cohort, termination of pregnancy was performed in 49 (29.7%) cases, intrauterine death occurred in 11 (6.7%), postnatal death occurred in 38 (23.0%) and 67 (40.6%) were alive at the latest follow-up, resulting in a total perinatal and pediatric mortality of 59.4%. Among the 105 liveborn neonates, 15 (14.3%) had extracardiac anomalies with significant impact on the postnatal course: one neonate died following repair of an encephalocele, six had successful treatment for various types of intestinal malrotation and/or atresia and one underwent hiatal hernia repair; the remaining seven had biliary atresia, of which five died and the two survivors are awaiting liver transplantation. The status of the spleen was assessed in 93/105 liveborn children and was found to be abnormal in 84/93 (90.3%). There were three cases of lethal sepsis, all associated with asplenia. Of the 38 postnatal deaths, 29 (76.3%) had a cardiac cause, seven (18.4%) had an extracardiac cause and in two (5.2%) the reason was uncertain.

CONCLUSIONS

Although the leading causes of death in fetuses and children with heterotaxy syndrome are cardiac, a small subset of fetuses have extracardiac anomalies with significant impact on outcome. These anomalies often escape prenatal detection, and therefore neonates at risk should be monitored for bowel obstruction, biliary atresia and immune dysfunction in order to allow timely intervention through a multidisciplinary approach. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

Prenatal diagnosis of bowel malposition using T2-weighted fetal MRI sequences

OBJECTIVE

The goal of this study was to investigate the capability of T2-weighted magnetic resonance imaging (MRI) in revealing fetal bowel malposition.

MATERIALS AND METHODS

All fetal MRI examinations (excluding central nervous system MRI examinations) performed in our department from January 2005 to January 2014 were retrospectively studied by 2 independent observers for situs, stomach and jejunum location on T2-weighted images. Patients data were also reviewed for results of ultrasound examinations, MRI indication, and gestational age. Abnormally positioned jejunums were classified into 3 groups: intrathoracic (A), extra-fetal (B) and abnormal intra-fetal (C). Prenatal data were compared to postnatal imaging, surgery or autopsy findings that served as standard of reference.

RESULTS

A total of 709 fetal MRI examinations were analyzed. In 64 fetus (9%), the jejunum was not present in the left subgastric area on T2-weighted MR images. In these 64 fetuses, proximal jejunum was intrathoracic (41/64, 64%, group A), extra-fetal (11/64, 17%, group B), or intra-abdominal but abnormally positioned (12/64, 19%, group C). Interobserver agreement was 100%. All diagnoses for fetuses in groups A and B (52 cases) were confirmed postnatally (41 cases) or at autopsy (11 cases). In group C, bowel malposition was suspected after ultrasound in only 2/12 fetuses (16.6%); it was confirmed postnatally in 1 fetus but not confirmed in the remaining one. In the 10 remaining fetuses (83%), malposition was confirmed postnatally although not initially suspected.

CONCLUSION

T2-weighted fetal MR images are useful for the prenatal diagnosis of bowel malposition, even when they are unsuspected on ultrasound examination.

DNAH6 and Its Interactions with PCD Genes in Heterotaxy and Primary Ciliary Dyskinesia

Heterotaxy, a birth defect involving left-right patterning defects, and primary ciliary dyskinesia (PCD), a sinopulmonary disease with dyskinetic/immotile cilia in the airway are seemingly disparate diseases. However, they have an overlapping genetic etiology involving mutations in cilia genes, a reflection of the common requirement for motile cilia in left-right patterning and airway clearance. While PCD is a monogenic recessive disorder, heterotaxy has a more complex, largely non-monogenic etiology. In this study, we show mutations in the novel dynein gene DNAH6 can cause heterotaxy and ciliary dysfunction similar to PCD. We provide the first evidence that trans-heterozygous interactions between DNAH6 and other PCD genes potentially can cause heterotaxy. DNAH6 was initially identified as a candidate heterotaxy/PCD gene by filtering exome-sequencing data from 25 heterotaxy patients stratified by whether they have airway motile cilia defects. dnah6 morpholino knockdown in zebrafish disrupted motile cilia in Kupffer’s vesicle required for left-right patterning and caused heterotaxy with abnormal cardiac/gut looping. Similarly DNAH6 shRNA knockdown disrupted motile cilia in human and mouse respiratory epithelia. Notably a heterotaxy patient harboring heterozygous DNAH6 mutation was identified to also carry a rare heterozygous PCD-causing DNAI1 mutation, suggesting a DNAH6/DNAI1 trans-heterozygous interaction. Furthermore, sequencing of 149 additional heterotaxy patients showed 5 of 6 patients with heterozygous DNAH6 mutations also had heterozygous mutations in DNAH5 or other PCD genes. We functionally assayed for DNAH6/DNAH5 and DNAH6/DNAI1 trans-heterozygous interactions using subthreshold double-morpholino knockdown in zebrafish and showed this caused heterotaxy. Similarly, subthreshold siRNA knockdown of Dnah6 in heterozygous Dnah5 or Dnai1 mutant mouse respiratory epithelia disrupted motile cilia function. Together, these findings support an oligogenic disease model with broad relevance for further interrogating the genetic etiology of human ciliopathies.

Heterotaxy is a birth defect involving randomization of left-right body axis. Its genetic etiology is still poorly understood, but recent studies suggest mutations in genes causing primary ciliary dyskinesia (PCD), a sinopulmonary disease, also can cause heterotaxy. Moreover, heterotaxy patients can show airway cilia dysfunction reminiscent of PCD. The link between these two seemingly disparate diseases reflects the common requirement for motile cilia in both left-right patterning and airway mucus clearance. Sequencing analysis of heterotaxy patients together with experimental modeling identified DNAH6 as a novel gene that can cause both heterotaxy and PCD. We further showed DNAH6 can interact with other PCD genes to mediate a more complex oligogenic etiology of disease. Thus experimental modeling with double gene knockdown showed digenic interactions of DNAH6 with DNAH5 or DNAI1 could disrupt motile cilia function in the respiratory epithelia and also cause heterotaxy in zebrafish embryos. These findings provide the first experimental evidence indicating oligogenic interactions can contribute to the complex genetics of heterotaxy.

Antenatally diagnosed right-sided stomach (dextrogastria): A rare rotational anomaly

AIM

Antenatal detection of right-sided stomach (dextrogastria) is rare, and its significance in regards to intestinal rotation is unclear. We aimed to review all cases of antenatally-diagnosed dextrogastria in our regional fetal medicine unit over 10years.

METHODS

A retrospective case-note review of patients identified from a prospectively-maintained database was performed.

RESULTS

Twenty cases of antenatally-diagnosed dextrogastria were identified from 2004 to 2014. There were 8 terminations and 1 intra-uterine death. One patient has no post-natal information obtainable. Ten infants were live-born, and 2 died secondary to cardiac disease in the neonatal period. All had significant cardiac/vascular anomaly on postnatal assessment, including the 3 neonates in whom dextrogastria was the only antenatal finding. Two neonates developed bilious vomiting and underwent Ladd's procedure. Operative findings were dextrogastria/malrotation in both. A third child had gastro-oesophageal reflux, and contrast demonstrated stable duodenal/midgut position. This child has not developed symptoms attributable to malrotation and not undergone surgery. All 3 of these infants had asplenia or polysplenia and were managed with antibiotic prophylaxis/immunisation. Five children in the series were not investigated for malrotation and have not come to surgical attention (one is known to be asplenic).

CONCLUSION

Antenatally-detected dextrogastria, even if apparently isolated, was always associated with postnatal significant cardiovascular anomaly, splenic abnormality or situs inversus. This may be important for antenatal counselling. We currently recommend postnatal echocardiography and splenic assessment, but reserve GI investigation/intervention for symptomatic malrotation owing to potential significant cardiac comorbidity.

Global genetic analysis in mice unveils central role for cilia in congenital heart disease

Congenital heart disease (CHD) is the most prevalent birth defect, affecting nearly 1% of live births; the incidence of CHD is up to tenfold higher in human fetuses. A genetic contribution is strongly suggested by the association of CHD with chromosome abnormalities and high recurrence risk. Here we report findings from a recessive forward genetic screen in fetal mice, showing that cilia and cilia-transduced cell signalling have important roles in the pathogenesis of CHD. The cilium is an evolutionarily conserved organelle projecting from the cell surface with essential roles in diverse cellular processes. Using echocardiography, we ultrasound scanned 87,355 chemically mutagenized C57BL/6J fetal mice and recovered 218 CHD mouse models. Whole-exome sequencing identified 91 recessive CHD mutations in 61 genes. This included 34 cilia-related genes, 16 genes involved in cilia-transduced cell signalling, and 10 genes regulating vesicular trafficking, a pathway important for ciliogenesis and cell signalling. Surprisingly, many CHD genes encoded interacting proteins, suggesting that an interactome protein network may provide a larger genomic context for CHD pathogenesis. These findings provide novel insights into the potential Mendelian genetic contribution to CHD in the fetal population, a segment of the human population not well studied. We note that the pathways identified show overlap with CHD candidate genes recovered in CHD patients, suggesting that they may have relevance to the more complex genetics of CHD overall. These CHD mouse models and >8,000 incidental mutations have been sperm archived, creating a rich public resource for human disease modelling.

Clinical course and outcome of antenatally detected atrioventricular block: experience of a single tertiary centre and review of the literature

OBJECTIVE

The objective is to study the course and outcome of fetuses with congenital atrioventricular block (AVB) in a single centre.

METHODS

Retrospective analysis of cases diagnosed prenatally with second and third degree AVB. The clinical characteristics and outcome of fetal AVB were evaluated including in utero treatment.

RESULTS

Sixty-two cases were studied. AVB was associated with a congenital heart defect (CHD-AVB) in 17 cases (27%), whereas it was isolated (i-AVB) in 45 (73%), 42 of which were associated with maternal antibodies. There were nine (52.9%) live births in the CHD-AVB group, five of which (55%) resulted in infant deaths. In the i-AVB group, there were 40/45 (88.9%) live births and 1/40 (2.5%) infant death; 36 (90%) babies required a permanent pacemaker. The only factor predictive of postnatal death was the presence of CHD (5/9 vs 1/39 or 48.7 [3.6; 1457.7], p < 0.001). Nineteen fetuses (40.5%) with i-AVB received steroids in utero. No difference in outcome was found between the AVB treated in utero versus the no-treatment group in terms of permanent pacemaker placement, postnatal death or development of dilated cardiomyopathy.

CONCLUSION

The most important prognostic factor for congenital AVB is the association with CHD. In utero treatment remains questionable.

Fetal bradyarrhythmia associated with congenital heart defects - nationwide survey in Japan

BACKGROUND

Because there is limited information on fetal bradyarrhythmia associated with congenital heart defects (CHD), we investigated its prognosis and risk factors.

METHODS AND RESULTS

In our previous nationwide survey of fetal bradyarrhythmia from 2002 to 2008, 38 fetuses had associated CHD. Detailed clinical data were collected from secondary questionnaires on 29 fetuses from 18 institutions, and were analyzed. The 29 fetuses included 22 with isomerism, 4 with corrected transposition of the great arteries (TGA) and 3 with critical pulmonary stenosis; 14 had complete atrioventricular block (AVB), 8 had second-degree AVB, and 16 had sick sinus syndrome; 5 died before birth, and 10 died after birth (5 in the neonatal period). Neonatal and overall survival rates for fetal bradyarrhythmia with CHD were 66% and 48%, respectively. Pacemaker implantation was needed in 17 cases (89%). Beta-sympathomimetics were administered in utero in 13 cases and were effective in 6, but were not associated with prognosis. All cases of corrected TGA or ventricular rate ≥70 beats/min survived. A ventricular rate <55 beats/min had significant effects on fetal myocardial dysfunction (P=0.02) and fetal hydrops (P=0.04), resulting in high mortality.

CONCLUSIONS

The prognosis of fetal bradyarrhythmia with CHD is still poor. The type of CHD, fetal myocardial dysfunction, and fetal hydrops were associated with a poor prognosis, depending on the ventricular rate.

Perinatal and infant outcomes of prenatal diagnosis of heterotaxy syndrome (asplenia and polysplenia)

Patients with heterotaxy syndrome (HS) have a range of anomalies and outcomes. There are limited data on perinatal outcomes after prenatal diagnosis. To determine the factors influencing perinatal and infant outcomes, we analyzed prenatal and postnatal variables in fetuses with HS from 1995 to 2011. Of 154 fetuses with HS, 61 (40%) had asplenia syndrome (ASP) and 93 (60%) had polysplenia syndrome (PSP). In the ASP group, 22 (36%) patients were elected for termination of pregnancy, 4 (10%) had fetal death, and 35 of 39 (90%) continued pregnancies were live born. In the PSP group, 12 (13%) patients were elected for termination of pregnancy, 5 (6%) had fetal death (4 with bradyarrhythmia), and 76 of 81 (94%) continued pregnancies were live born. Bradyarrhythmia was the only predictor of fetal death. In the live-born ASP group, 43% (15 of 35) died, 7 because of pulmonary vein stenosis, 4 postoperatively, and 4 because of noncardiac causes. In the live-born PSP group, 13% (10 of 76) died, 5 postoperatively, 2 from bradyarrhythmia, 1 from a cardiac event, and 2 from noncardiac causes. Pulmonary vein stenosis and noncardiac anomalies were independent risk factors for postnatal death. Only 8% of ASP patients achieved biventricular circulation, compared with 65% of PSP patients. In the live-born cohort, the 5-year survival rate was 53% for ASP and 86% for PSP. In conclusion, most PSP patients are currently alive with biventricular circulation in contrast with few ASP patients. Bradyarrhythmia was the only predictor of fetal death. Pulmonary vein stenosis and noncardiac anomalies were predictors of postnatal death.

Perinatal outcome in fetuses with heterotaxy syndrome and atrioventricular block or bradycardia

Congenital atrioventricular (AV) block is commonly associated with heterotaxy syndrome; together they have reportedly low survival rates (10-25%). However, information about perinatal outcome and predictors of non-survival after prenatal diagnosis of this association is scarce. Therefore, we studied fetuses with heterotaxy syndrome and bradycardia or AV-block diagnosed between 1995 and 2011, and analyzed pre and post-natal variables. The primary outcome was death and the secondary outcome was pacemaker placement. Of the 154 fetuses with heterotaxy syndrome, 91 had polysplenia syndrome, 22/91(24%) with bradycardia or AV-block. Thirteen (59%) patients had sinus bradycardia at diagnosis, 8 (36%) complete AV block, and 1 (5%) second-degree AV-block. Three patients elected for termination of pregnancy (3/22, 14%), 4 had spontaneous fetal demise (4/22, 18%), and 15 (15/22, 68%) were live-born. Of the fetuses with bradycardia/AV-block, 30% presented with hydrops, 20% had ventricular rates <55 beats/min, and 10% had cardiac dysfunction. Excluding termination of pregnancy, 15/19 fetuses (79%) survived to birth. Among the 15 live-born patients, 4 had bradycardia and 11 had AV-block. A further 3 patients died in infancy, all with AV-block who required pacemakers in the neonatal period. Thus, the 1-year survival rate, excluding termination of pregnancy, was 63% (12/19). Of the remaining 12 patients, 9 required pacemaker. Predictors of perinatal death included hydrops (p < 0.0001), ventricular dysfunction (p = 0.002), prematurity (p = 0.04), and low ventricular rates (p = 0.04). In conclusion, we found a higher survival rate (63%) than previously published in patients with heterotaxy syndrome and AV block or bradycardia diagnosed prenatally. Hydrops, cardiac dysfunction, prematurity and low ventricular rates were predictors of death.

Defects in laterality with emphasis on heterotaxy syndromes with asplenia and polysplenia: an autopsy case series at a single institution

Heterotaxy is a rare disease with high morbidity and mortality. Controversy exists over how to classify these syndromes with most cases stratified into asplenia/polysplenia syndromes or right/left isomerism. In an effort to review comprehensively specific pheonotypes associated with heterotaxy syndromes, we reviewed published cases series, adopted a classification scheme based on spleen status, and evaluated autopsy cases retrospectively with abnormal laterality at our institution. We categorized 116 cases as situs inversus totalis, polysplenia, asplenia, and single right-sided spleen. Cardiovascular abnormalities occurred in 87.1% of polysplenia, 90.5% of asplenia, and all cases of single right-sided spleen. For polysplenia, 48.9% had bilateral bilobed lungs, 87% had right-sided stomach, 58.1% had midline symmetric liver, and 60.4% had malrotated intestines. For asplenia, 51.9% had bilateral trilobed lungs, 86.7% had right-sided stomach, 45.8% had symmetric liver, and 65.5% had malrotated intestines. Atrioventricular septal defects occurred in 91.2% of asplenia compared to 56.8% of polysplenia cases. Eight percent had pulmonary/aortic stenosis or atresia. Double outlet right ventricle was more common in polysplenia (32.6%) compared to asplenia (21.4%). Total anomalous systemic venous return was described in 55.6% of polysplenia and total anomalous pulmonary venous connections in 81% of asplenia cases. Greater than half of the cases had no heterotaxy diagnosis. Although, we found similar heterotaxy-associated characteristics, the frequencies differed from previous studies. We found great variation in how heterotaxy-associated defects were described, diagnosed, and reported. Although there are known associated characteristics with the polysplenia/asplenia syndromes, correct identification requires a standardized approach for diagnosis and reporting.

Prenatal diagnosis of atrial isomerism in the Korean population

OBJECTIVE

To report our experiences in the prenatal diagnosis of atrial isomerism and postnatal outcomes.

METHODS

A total of 80 fetuses prenatally diagnosed with atrial isomerism were retrospectively analyzed between 1999 and 2011 at a single institution.

RESULTS

Of 43 fetuses with prenatally diagnosed right atrial isomerism (RAI), 40 cases were analyzed. The diagnostic accuracy was 93%. The main intracardiac anomalies in RAI were atrioventricular septal defect (AVSD), abnormal pulmonary venous connection, bilateral superior vena cava (BSVC), and pulmonary atresia. Among 28 live births, three infants were lost to follow up, and the overall survival rate was 60%. Of 37 fetuses with prenatally diagnosed left atrial isomerism (LAI), 35 were evaluated. The diagnostic accuracy was 97%. The main intracardiac anomalies in LAI were ventricular septal defect, BSVC, AVSD, double outlet right ventricle, and bradyarrhythmia. Among seven patients with bradyarrhythmia, only one showed a complete atrioventricular block. All fetuses had an interrupted inferior vena cava with azygous continuation. The overall survival rate was 90%.

CONCLUSION

Our study confirms the previous findings of fetal atrial isomerism. We also demonstrates a much lower prevalence of AVSD and complete heart block in LAI and a better survival rate in RAI. Although the postnatal outcomes for RAI were worse than those for LAI, successful postnatal surgery with active management improved the survival rate.

Successful blood sampling through azygos continuation with interrupted inferior vena cava. A case report and review of the literature

Interrupted inferior vena cava (IVC) with azygos continuation is a rare congenital anomaly, and is frequently associated with other cardiovascular malformations and situs anomalies, such as left isomerism. These patients usually develop deep vein thrombosis (DVT), and asymptomatic patients above 60 years of age are very rare. Here we report a case of interrupted IVC which we diagnosed in a 72-year-old woman. She was admitted to our hospital suffering from heart failure and supraventricular tachycardia. Echocardiography detected secundum atrial septal defect (ASD). An abnormal paravertebral pleural line on the chest X-rays indicated the existence of venous anomaly. Anatomical images obtained by Multidetector Computed Tomography (MDCT) helped us to successfully perform right heart catheterization procedures through azygos continuation including blood sampling from pulmonary veins. Even in elderly patients, a careful examination of chest X-rays can indicate undiagnosed venous anomalies; thus, it is critically important before planning surgical or interventional procedures.

Role of four-dimensional ultrasound (spatiotemporal image correlation and sonography-based automated volume count) in prenatal assessment of atrial morphology in cardiosplenic syndromes

OBJECTIVE

To assess the diagnostic role of four-dimensional ultrasound using spatiotemporal image correlation and Sonography-based Automated Volume Count (STIC-SonoAVC) in the identification of the morphology of the atrial appendages in cases with cardiosplenic syndrome.

METHODS

This was a retrospective investigation of 22 fetuses with cardiosplenic syndromes seen at our institution over a 5-year period from January 2004. As control groups, 10 normal fetuses, five cases with a non-isomeric atrioventricular septal defect and five cases with other congenital heart diseases were also analyzed. For all fetuses, one or more cardiac volume datasets were available for offline analysis. Two-dimensional and four-dimensional echocardiography was carried out in all cases at the time of diagnosis using high quality three-dimensional equipment. Dedicated software was used to assess chamber morphology using the SonoAVC technique, which allows the creation of casts of hollow structures. Two different operators used the software. The first performed all steps up to positioning of the region of interest box. The second operator, who was blinded to clinical information, then rendered the cardiac chambers using the SonoAVC technique. This operator then used the rendered image to subjectively assess atrial morphology.

RESULTS

Suitable rendered images of the cardiac chambers could be produced in 40/42 fetuses. In two cases of left atrial isomerism, advanced (34 weeks) and early (13 weeks) gestational age made it impossible to obtain adequate rendered images. In the remaining 40 cases (13 cases of left atrial isomerism, seven cases of right atrial isomerism, five cases of non-isomeric atrioventricular septal defect, five cases of other congenital heart diseases and 10 normal fetuses), atrial morphology was correctly identified by evaluation of the rendered images.

CONCLUSION

Four-dimensional ultrasound with SonoAVC rendering allows correct identification of the morphology of atrial appendages in all cases of cardiosplenic syndromes in which an adequate cardiac volume dataset can be obtained for analysis.