Outcomes of left atrial isomerism over a 28-year period at a single institution

The Significance of Congenital Portosystemic Shunts in Congenital Heart Disease and the Bizarre Phenomenon of Alternating Portosystemic and Systemic-Portal Shunting

Congenital portosystemic shunts (CPSSs) are rare vascular anomalies characterized by abnormal connections between the portal/splanchnic veins and the systemic veins. CPSSs often occur as an isolated congenital anomaly, but they can also coexist with congenital heart disease (CHD). Owing to their myriad consequences on multiple organ systems, familiarity with CPSS is of tremendous importance to the care of patients with CHD. The rationale and timing for interventions to embolize CPSS in this scenario are discussed. Specific shunt embolization techniques are beyond the scope of this article.

Long-Term Survival After Single-Ventricle Palliation: A Swedish Nationwide Cohort Study

BACKGROUND

Long-term survival after single-ventricle palliation and the effect of dominant ventricle morphology in large, unselected series of patients are scarcely reported.

METHODS AND RESULTS

This nationwide cohort study included all children undergoing operation with single-ventricle palliation during their first year of life in Sweden between January 1994 and December 2019. Data were obtained from institutional records and assessment of underlying cardiac anomaly and dominant ventricular morphology was based on complete review of medical records, surgical reports, and echocardiographic examinations. Data on vital status and date of death were retrieved from the Swedish Cause of Death Register, allowing for complete data on survival. Among 766 included patients, 333 patients (43.5%) were classified as having left or biventricular dominance, and 432 patients (56.4%) as having right ventricular (RV) dominance (of whom 231 patients had hypoplastic left heart syndrome). Follow-up was 98.7% complete (10 patients emigrated). Mean follow-up was 11.3 years (maximum, 26.7 years). Long-term survival was significantly higher in patients with left ventricular compared with RV dominance (10-year survival: 91.0% [95% CI, 87.3%-93.6%] versus 71.1% [95% CI, 66.4%-75.2%]). RV dominance had a significant impact on outcomes after first-stage palliation but was also associated with impaired survival after completed total cavopulmonary connection. In total, 34 (4.4%) patients underwent heart transplantation. Of these 34 patients, 25 (73.5%) had predominant RV morphology.

CONCLUSIONS

This study provides clinically relevant knowledge about the long-term prognosis in patients with different underlying cardiac anomalies undergoing single-ventricle palliation. RV dominance had a significant impact on outcomes after initial surgical treatment but was also associated with impaired survival after completed Fontan circulation.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03356574.

Cardiac Laterality: Surgical Results of Right Atrial Isomerism

Right atrial isomerism (RAI) is a complex entity with varying diagnostic and treatment outcomes due to its rarity. Treatment options range from palliative to corrective surgeries, resulting in heterogeneous outcomes. The aim of this study was to analyze the results obtained after cardiac surgery in patients with RAI. A retrospective study was conducted, including patients diagnosed with RAI who underwent cardiac surgery. Their follow-up was from 1 January 2010 to 31 March 2020. Demographic characteristics and perioperative conditions were described. Thirty-eight patients were included, the median age was 4 years (IQR 2-9.2) and 57.9% were men. The main diagnoses were atrioventricular canal (63.2%) and pulmonary stenosis (55.3%). The most common surgical procedures were modified Blalock-Taussig shunt (65.8%) and total cavopulmonary connection with an extracardiac conduit fenestrated without cardiopulmonary bypass (15.9%). We did not find any factors associated with negative outcomes in these patients. The overall survival was 86.8%, with a better outcome in those who did not require reintubation (log rank, p < 0.01). The survival of RAI was similar to other centers. Individuals with RAI should be evaluated rigorously to determine an adequate repair strategy, considering high morbidity and mortality.

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.

Which side are they on? Diagnosing primary ciliary dyskinesias in low- or middle-income countries: A review and case series

Background

Primary ciliary dyskinesia (PCD) is a rare genetic condition with a variable clinical presentation, making its diagnosis a challenge. We describe two unrelated sibling pairs with PCD: adult siblings in the first and perinatal/neonatal in the second. Both families highlight the more common and rarer clinical manifestations of PCD. We use these cases to highlight: (i) current understanding of the underlying genetic and pathophysiological mechanisms of PCD; (ii) the diversity of cardiac and respiratory features of PCD across a wide age range; (iii) aspects of the history and clinical examination that should raise suspicion of PCD; and (iv) the role of next-generation sequencing gene panel testing in confirmation of the diagnosis. We note genomic evidence predicting that PCD is relatively common in black African populations.

Study synopsis

What the study adds. This review of two sibling pairs illustrates the variable histories, presentations, diagnostic processes and clinical courses of primary ciliary dyskinesia (PCD) in low- or middle-income countries (LMICs), highlighting the diagnostic challenges faced when encountering such patients in settings where there may not be access to specialised resources. Possible diagnostic tools that can be used are discussed, weighing up their pros and cons in an LMIC setting, and a potential diagnostic approach that can be adapted to the treating clinician's own context is provided.Implications of the findings. Confirmation of the diagnosis of primary ciliary dyskinesia is no longer limited to well-resourced institutions, but can be done in less specialised environments using novel, highly accurate next-generation sequencing gene panel testing, reducing the need to transport patients as well as the overall cost to the healthcare system. Well-resourced institutions that see high volumes of patients with PCD can invest in new highly sensitive diagnostic tools such as high-speed video microscopy. There is a need for research investigating the validity of tools such as ciliary immunofluorescence in the South African population.

A puzzling CHD: a late diagnosis of left atrial isomerism

We present a case of a 41-year-old patient with an unknown complex cardiac anatomy, who was previously submitted to two cardiac surgeries. Using multimodality imaging, a retrospective diagnosis was established, revealing a heterotaxy syndrome (left isomerism).

Left-Sided Heart Defects and Laterality Disturbance in Hypoplastic Left Heart Syndrome

Hypoplastic left heart syndrome (HLHS) is a complex congenital heart disease characterized by hypoplasia of left-sided heart structures. The developmental basis for restriction of defects to the left side of the heart in HLHS remains unexplained. The observed clinical co-occurrence of rare organ situs defects such as biliary atresia, gut malrotation, or heterotaxy with HLHS would suggest possible laterality disturbance. Consistent with this, pathogenic variants in genes regulating left-right patterning have been observed in HLHS patients. Additionally, Ohia HLHS mutant mice show splenic defects, a phenotype associated with heterotaxy, and HLHS in Ohia mice arises in part from mutation in Sap130, a component of the Sin3A chromatin complex known to regulate Lefty1 and Snai1, genes essential for left-right patterning. Together, these findings point to laterality disturbance mediating the left-sided heart defects associated with HLHS. As laterality disturbance is also observed for other CHD, this suggests that heart development integration with left-right patterning may help to establish the left-right asymmetry of the cardiovascular system essential for efficient blood oxygenation.

Long-Term Surgical Outcomes of Patients With Isomeric Right and Left Atrial Appendages

Objectives: To compare the long-term outcomes of biventricular, univentricular, and so-called one-and-one-half ventricular repairs in patients with left and right isomerism. Methods: Surgical correction was undertaken, between 2000 and 2021, in 198 patients with right, and 233 with left isomerism. Results: The median age at operation was 24 days (interquartile range [IQR]: 18-45) and 60 days (IQR: 29-360) for those with right and left isomerism, respectively. Multidetector computed-tomographic angiocardiography demonstrated more than half of those with right isomerism had superior caval venous abnormalities, and one-third had a functionally univentricular heart. Almost four-fifths of those with left isomerism had an interrupted inferior caval vein, and one-third had complete atrioventricular septal defect. Biventricular repair was achieved in two-thirds of those with left isomerism, but under one-quarter with right isomerism (P < .001). Hazard regression for mortality revealed odds for prematurity at 5.5, pulmonary atresia at 2.81, atrioventricular septal defect with a common valvar orifice at 2.28, parachute mitral valve at 3.73, interrupted inferior caval vein at 0.53, and functionally univentricular heart with a totally anomalous pulmonary venous connection at 3.77. At a median follow-up of 124 months, the probability of survival was 87% for those with left, and 77% for those with right isomerism (P = .006). Conclusions: Multimodality imaging characterizes and delineates the relevant anatomical details, facilitating surgical management of individuals with isomeric atrial appendages. Continuing higher mortality despite surgical intervention in those with right isomerism points to the need for the reassessment of strategies for management.

Impact of gastrointestinal comorbidities in patients with right and left atrial isomerism

BACKGROUND AND AIM

Heterotaxy syndrome, being right atrial isomerism (RAI) or left atrial isomerism (LAI), often presents with Congenital Heart Disease (CHD). Intestinal abnormalities, including malrotation are common. We assessed the spectrum of gut abnormalities and their impact on medium-term outcome in a cohort of patients with fetal and postnatal diagnoses of heterotaxy syndrome.

METHODS

We reviewed the cardiology records of heterotaxy syndrome patients from two centres, regarding the presence of CHD, time for cardiac intervention, presence of gastrointestinal abnormalities, and type/time of surgery. A questionnaire about gastrointestinal status was sent to patients <18 years old. Kaplan-Meier curves were derived for survival data and freedom from intervention.

RESULTS

Data were included for 182 patients (49 RAI and 133 LAI) of 247 identified. Questionnaires were sent to 77 families and 47 replied. CHD was present in all RAI and 61.7% of LAI cases. Thirty-eight patients had abdominal surgery (20.9%), similar for RAI and LAI (20.4% versus 21%, p> 0.99): Ladd procedure in 17 (44.7%), non-Ladd in 12 (31.5%), and both procedures in 9 (23.7%). Ten-year freedom from Ladd procedure for all was 86% for the whole cohort (RAI = 87%; LAI = 85%, p = 0.98). Freedom from any gastrointestinal surgery at 10 years was 79% for the whole cohort (RAI = 77%; LAI = 80%, p = 0.54). Ten-year freedom from cardiac surgery was 31% for the whole cohort (RAI = 6%; LAI = 43%, p < 0.0001).

CONCLUSIONS

In our cohort, one in five patients required abdominal surgery, mostly in their first year of life, similar for RAI and LAI. Between 1 and 10 years of follow-up, the impact of gastrointestinal abnormalities on outcome was minimal. Medium term survival was related to CHD.

Society for Cardiovascular Magnetic Resonance/European Society of Cardiovascular Imaging/American Society of Echocardiography/Society for Pediatric Radiology/North American Society for Cardiovascular Imaging Guidelines for the use of cardiovascular magnetic resonance in pediatric congenital and acquired heart disease : Endorsed by The American Heart Association

Cardiovascular magnetic resonance (CMR) has been utilized in the management and care of pediatric patients for nearly 40 years. It has evolved to become an invaluable tool in the assessment of the littlest of hearts for diagnosis, pre-interventional management and follow-up care. Although mentioned in a number of consensus and guidelines documents, an up-to-date, large, stand-alone guidance work for the use of CMR in pediatric congenital 36 and acquired 35 heart disease endorsed by numerous Societies involved in the care of these children is lacking. This guidelines document outlines the use of CMR in this patient population for a significant number of heart lesions in this age group and although admittedly, is not an exhaustive treatment, it does deal with an expansive list of many common clinical issues encountered in daily practice.

Society for Cardiovascular Magnetic Resonance/European Society of Cardiovascular Imaging/American Society of Echocardiography/Society for Pediatric Radiology/North American Society for Cardiovascular Imaging Guidelines for the Use of Cardiac Magnetic Resonance in Pediatric Congenital and Acquired Heart Disease: Endorsed by The American Heart Association

Cardiovascular magnetic resonance has been utilized in the management and care of pediatric patients for nearly 40 years. It has evolved to become an invaluable tool in the assessment of the littlest of hearts for diagnosis, pre-interventional management and follow-up care. Although mentioned in a number of consensus and guidelines documents, an up-to-date, large, stand-alone guidance work for the use of cardiovascular magnetic resonance in pediatric congenital 36 and acquired 35 heart disease endorsed by numerous Societies involved in the care of these children is lacking. This guidelines document outlines the use of cardiovascular magnetic resonance in this patient population for a significant number of heart lesions in this age group and although admittedly, is not an exhaustive treatment, it does deal with an expansive list of many common clinical issues encountered in daily practice.

The surgical anatomy of hearts with isomeric atrial appendages-implications for surgical management

OBJECTIVES

The most severe combinations of cardiac malformations exist in individuals having jumbled-up thoracic and abdominal organs. These patients make up 2 distinct syndromes. As yet, the consensus is lacking on how best to describe the subsets. The subsets are frequently grouped together in terms of 'heterotaxy'. The surgical approaches to the subsets, however, are markedly different. We reviewed our experiences with regard to the anatomy as observed in the autopsy room, by the analysis of computed tomographic studies, and in the operating room, to assess whether the lesions might be segregated on the basis of isomerism of the atrial appendages.

METHODS AND RESULTS

A review of our findings from the examination of specimens from several archives, along with investigation of a large cohort of patients being prepared for surgical treatment, showed that individuals can uniformly be segregated into subgroups on the basis of isomeric arrangement of the atrial appendages. In all instances, this was made possible by using the criterion of the extent of the pectinate muscles within the appendages as judged relative to the atrial vestibules. Segregation on this basis, which correlated excellently with the bronchial arrangement, sets the scene for an appropriate description of the remainder of the heart, providing the cardiac surgeon with all the inferences required for appropriate surgical intervention.

CONCLUSIONS

When assessing individuals having the features of so-called 'heterotaxy', it is possible to segregate the groups into subsets of individuals having either isomeric right or left atrial appendages. This approach provides the framework for the assessment of appropriate surgical management.

Surgical management of hearts with isomeric atrial appendages

BACKGROUND AND AIM

On the basis of previously published accounts, coupled with our own experience, we have assessed the surgical approaches to patients with isomeric atrial appendages.

METHODS

We reviewed pertinent published studies on surgical treatment of individuals with isomeric atrial appendages, with the pertinent surgical details provided by most of the manuscripts.

RESULTS

Half of patients with right isomerism, and two-thirds of those with left isomerism have bilateral superior caval veins. Azygos extension of the inferior caval vein is reported in three-quarters of those with left isomerism. The coronary sinus is universally absent in right isomerism, along with totally anomalous pulmonary venous connection, and is absent in two-fifths of those with left isomerism. Univentricular atrioventricular connections are expected in up to three-quarters of those with right isomerism. Atrioventricular septal defect is reported in up to four-fifths, more frequently in right isomerism, with such patients typically having discordant ventriculoatrial connections or double outlet right ventricle. Reported mortalities extend to 85% for those with right, and 50% for those with left isomerism. In right isomerism, mortality is up to 54% for systemic-to-pulmonary arterial shunting, up to 75% for univentricular repair, and up to 95% for repair of totally anomalous pulmonary venous connection itself. No more than one-quarter had undergone Fontan completion, with reported mortalities of 21%.

CONCLUSION

Early surgical results are satisfactory in patients with left isomerism, but disappointing for those with right. Recent advances in cardiac and liver transplantation may offer improved survival.

Utility of Three-Dimensional Printed Model in Biventricular Repair of Complex Congenital Cardiac Defects: Case Report and Review of Literature

Heterotaxy is a rare syndrome associated with cardiac complexity, anatomic variability and high morbidity and mortality. It is often challenging to visualize and provide an accurate diagnosis of the cardiac anatomy prior to surgery with the use of conventional imaging techniques. We report a unique case demonstrating how the use of three-dimensional (3D) cardiac printed model allowed us to better understand the anatomical complexity and plan a tailored surgical approach for successful biventricular repair in a patient with heterotaxy syndrome.

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.

Multimodality imaging of developmental splenic anomalies: tips and pitfalls

Anomalies in number and location may occur during splenic development. This review aims to offer a brief overview of splenic function and embryology and a detailed account of the imaging appearances using different imaging techniques of the normal spleen and various congenital splenic anomalies including (1) abnormal viscero-atrial situs, (2) splenogonadal fusion, (3) intrapancreatic accessory spleen, (4) wandering spleen, and (5) splenosis. Emphasis is placed on the salient features that help radiologists recognise important associations (e.g., asplenia/polysplenia in situs abnormalities), avoid diagnostic pitfalls (e.g., mistaking intrapancreatic accessory spleen as pancreatic neoplasms), and potential complications (e.g., acute torsion in wandering spleen). The correct identification of the said anomalies from more sinister causes, such as malignancies, are essential, where early intervention is necessary.

Discordant Post-natal Patterns in Fetuses With Heterotaxy Syndrome: A Retrospective Single-Centre Series on Outcome After Fetal Diagnosis

OBJECTIVE

Cardiac and extra-cardiac anomalies in 46 pre-natally diagnosed cases of heterotaxy were compared to post-natal anatomical patterns in order to reveal discordant findings. Second, the outcome of these fetuses was evaluated.

METHODS

Fetuses with heterotaxy, diagnosed in a tertiary referral centre, were analysed retrospectively. Based on the foetal abdominal situs view, right atrial isomerism (RAI) and left atrial isomerism (LAI) were defined as foetal sub-types. Post-natally, discordant anatomical patterns for broncho-pulmonary branching, atrial appendage morphology, and splenic status were further clarified with CT scans. In summary, the spectrum of pre-natally and post-natally detected cardiac and extra-cardiac anomalies is systematically reviewed. Necessary surgical interventions and mid-long-term outcomes were compared between the two sub-types in surviving infants.

RESULTS

A total of 46 fetuses with heterotaxy were included; LAI was diagnosed in 29 (63%) fetuses and RAI was diagnosed in 17 (37%) fetuses. Extra-cardiac anomalies were noted in 35% of fetuses. Seven out of the 29 fetuses (24%) with LAI had atrio-ventricular block (AVB) and four of these cases presented with hydrops. Twenty nine out of the 46 participating fetuses (63%) were live births, with 62% in the LAI group and 65% in the RAI group. Five fetuses were lost to follow-up. At the age of 1 year, the overall survival of live births [estimate (95% CI)] was 67% (48; 92%) in patients with LAI and 55% (32; 94%) in patients with RAI. At the age of 5 years, the estimates were 67% (48; 92%) in the LAI group and 46% (24-87%) in the RAI group. The median survival (first quartile; third quartile) was 11.1 (0.1; 14) years for patients with LAI and 1.3 (0.09; NA) years for patients with RAI. Of 17 children who had undergone cardiac surgery, five (29%) children achieved a bi-ventricular repair and 12 (70%) children achieved a uni-ventricular palliation. Three were primarily palliated, but converted to bi-ventricular thereafter. Foetal subtype definition of heterotaxy based on the abdominal situs and post-natal thoracic imaging studies showed a discordant pattern of broncho-pulmonary branching and atrial appendage anatomy in 40% of our live-born children.

CONCLUSION

Heterotaxy is a rare and complex condition with significant morbidity and mortality related to severe cardiac and extra-cardiac associations. Accurate pre-natal diagnosis can help identify the fetuses at risk and allow for timely intervention in a multi-disciplinary setting. Further studies are warranted to shed light on the exact sub-type definition in fetuses with heterotaxy and the presence of discordant post-natal patterns.

Cardiac surgery in patients with atrial isomerism: Long-term results and outcomes

PURPOSE

The aim of the study was to identify, determine, and analyze the clinical and surgical outcomes of patients with atrial isomerism (AI) undergoing cardiac surgery.

METHODS

A retrospective study was carried out. Patients with diagnosis of AI undergoing cardiac surgery at the National Institute of Cardiology Ignacio Chávez, from January 1, 2010 and March 31, 2020 were included; demographic characteristics and perioperative conditions of the patients were considered.

RESULTS

Sixty-five patients were included, with an average age of 6.4 ± 4.9 years, 50.8% males. Thirty-eight (58.5%) had right atrial isomerism (RAI) and 27 (41.5%) had left atrial isomerism (LAI); univentricular physiology (78.5%) predominated. Atrioventricular septal defect (AVSD) in RAI and septal defects in LAI were identified as the main associated defects. The most common surgical procedures performed were modified Blalock-Taussig shunt (MBTS) (27.6%), MBTS with total anomalous pulmonary venous connection (TAPVC) repair (15.3%) and total cavopulmonary connection (TCPC) with an extracardiac conduit fenestrated (10.8%); 100% RAI required a univentricular approach, while in LAI it was 48.1%. Overall survival was 92.3%, with 100% survival in LAI with biventricular physiology and 86.8% in RAI with univentricular physiology.

CONCLUSIONS

The survival of our institution is similar to that of other referral centers, where patients with LAI had a better evolution than RAI; in addition, the univentricular approach was required in all with RAI. Patients with AI must undergo a rigorous evaluation to determine an adequate repair strategy, considering univentricular RAI with a high possibility of morbidity and mortality.

Postmortem Assessment of Isolated Congenital Heart Defects Remains Essential Following Termination of Pregnancy

OBJECTIVES

To investigate the correlation between prenatal ultrasound (US) and autopsy findings in pregnancies terminated due to isolated congenital heart defects (CHDs), including CHDs associated with heterotaxy syndrome.

MATERIALS AND METHODS

The material consists of 67 fetuses with prenatally detected isolated CHDs or CHDs associated with heterotaxy syndrome at a tertiary center in Norway between 1985 and 2014. The main CHDs were categorized into subdiagnoses of CHDs in accordance with ICD-10. The US and autopsy findings were categorized according to degree of concordance.

RESULTS

Gestational age at termination was 12 + 0-22 + 6 weeks. Hypoplastic left heart syndrome was the most common main diagnosis among the 67 fetuses (32.8%). There was full agreement between US and autopsy findings in 97.4% (222/228) of all subdiagnoses. The discrepant findings in three fetuses had no influence on the decision to terminate the pregnancy.

CONCLUSIONS

The correlation was high between prenatal US and postmortem findings in fetuses with isolated CHDs. Meticulous assessment of cardiac anatomy is particularly necessary when the decision to terminate relies on isolated CHDs. The trend of earlier termination challenges verification of diagnoses at autopsy. Consequently, the fetus should be examined at a tertiary center with fetal medicine specialists, pediatric cardiologists and perinatal pathologists.

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.

Human Laterality Disorders: Pathogenesis, Clinical Manifestations, Diagnosis, and Management

Human laterality disorders comprise a group of diseases characterized by abnormal location (situs) and orientation of thoraco-abdominal organs and vessels across the left-right axis. Situs inversus totalis is mirror image reversal of thoraco-abdominal organs/great vessels. Situs ambiguus, better known as heterotaxy, is abnormal arrangement of thoraco-abdominal organs across the left-right axis excluding situs inversus totalis. Heterotaxy, also referred to as atrial or atrial appendage isomerism, is characterized by abnormal location of left-sided or right-sided organs with loss of asymmetry of normally paired asymmetric organs. It is associated with a variety of anomalies involving the heart, great vessels, lungs and intra-abdominal organs. Right and left atrial isomerism are associated with multiple complex congenital cardiac and vascular anomalies, many of which are lethal when untreated. Isomerism may also affect the lungs, spleen, liver, gall bladder, and intestines. Innovative surgical therapy of heterotaxy/isomerism has reduced early mortality and markedly improved long-term prognosis.

Analysis of the 2020 European Society of Cardiology (ESC) Guidelines for the Management of Adults With Congenital Heart Disease (ACHD)

Adult congenital heart disease (ACHD) continues to rapidly increase worldwide. With an estimated 1.5 million adults with ACHD in the USA alone, there is a growing need for better education in the management of these complex patients and multiple knowledge gaps exist. This manuscript comprehensively reviewed the recent (2020) updated European Society of Cardiology Guidelines for the management of ACHD created by the Task Force for the management of adult congenital heart disease of the European Society of Cardiology, with perioperative implications for the adult cardiac anesthesiologist and intensivist who may be called upon to manage these complex patients.

Extracorporeal Membrane Oxygenation Complicated by an Interrupted Inferior Vena Cava

Heterotaxy refers to a congenital disorder in which there is a disruption of the normal left-right axis, resulting in duplication of one laterality, and can affect all of the thoracic and abdominal organs. Findings include atrial isomerism, vascular abnormalities affecting the great vessels, ciliary dyskinesia, polysplenia or asplenia, biliary atresia, and gut malrotation. These anomalies can present unique challenges in the critical care setting, particularly in those requiring mechanical circulatory support. Here, we present a patient with acute respiratory distress syndrome requiring venovenous extracorporeal oxygenation which was complicated by a persistent impedance of flow. She was subsequently discovered to have an interrupted inferior vena cava, where lower limb venous drainage returned to the heart via the azygos and hemiazygos systems. We use this case to also highlight other manifestations of heterotaxy which may affect critical care.

Echocardiographic Identification of Pulmonary Artery Flow Reversal: An Indicator of Adverse Outcomes in Single Ventricle Physiology

Individuals with single ventricle congenital heart disease (CHD) undergo multiple staged surgical palliations. Staged single ventricle palliation with a superior cavopulmonary connection (SCPC) in infancy followed by a Fontan in early childhood relies on passive, unobstructed pulmonary blood flow and normal pulmonary vasculature. We hypothesized that patients with echocardiographic identification of retrograde flow in a branch pulmonary artery (PA) after SCPC or Fontan are at increased risk for adverse outcomes. We conducted a retrospective chart review of patients seen at Children's Wisconsin from 1999 to 2019. Inclusion criteria included a history of single ventricle congenital heart disease and surgical palliation with a superior cavopulmonary connection (SCPC). We created two cohorts based on transthoracic echocardiographic identification of branch PA flow patterns: those with color Doppler-defined pulmonary artery flow reversal (PA reversal cohort) and those with normal anterograde flow (Non-reversal cohort). We identified 21 patients in the PA reversal cohort and 539 patients in the Non-reversal cohort. The PA reversal cohort had increased hospital length of stay after SCPC palliation (p < 0.001) and decreased transplant-free survival (p = 0.032), but there was no difference in overall survival (p = 0.099). There was no difference in hospital length of stay after Fontan (p = 0.17); however, the PA reversal cohort was significantly less likely to progress to Fontan palliation during early childhood (p = 0.005). Echocardiographic color Doppler identification of branch PA flow reversal in patients with single ventricle physiology is a high-risk indicator for adverse short- and long-term outcomes.

Left isomerism with bilateral superior vena cava, interrupted inferior vena cava and tetralogy of Fallot

The association of left isomerism with tetralogy of Fallot (TOF) is rare and reported as scattered case reports. Complex congenital cardiac and noncardiac malformations are known to be associated with left isomerism, but right-sided obstructive lesions are rare. We present our experience with a case of left isomerism with bilateral superior vena cava, interrupted inferior vena cava, and TOF managed by atrial septation and intracardiac repair.

Senning Procedure for Physiological Atrial Inversion With Left Atrial Isomerism

We present the case of an infant with left atrial isomerism with complex pulmonary and systemic venous connections that resulted in physiological parallel circulation in the setting of ventriculoarterial concordance who was surgically treated using the Senning procedure. This case highlights a rare cause for cyanosis due to poor mixing from a parallel circulation and an issue with nomenclature. (Level of Difficulty: Advanced.).

Standardized Approach to Intervention for Intestinal Malrotation in Single Ventricle Patients with Heterotaxy Syndrome: Impact on Interstage Attrition and Time to Superior Cavopulmonary Connection

Heterotaxy syndrome (HS) is a significant determinant of outcome in single ventricle (SV) physiology. Attrition rate and time-related events associated with intestinal malrotation (IM) are, yet, to be determined. We sought to evaluate hospital and interstage outcomes in relation with operative intervention for IM (IMO). Twelve SV/HS patients, who underwent IMO, from January 2004 to December 2016, were studied. Early shunt failure, time to superior cavopulmonary connection (SCPC) and interstage attrition were assessed. Since September 2014, based on a comprehensive standardized protocol, IMO was performed at the time of hospitalization for stage-I palliation (S1P) irrespective of clinical manifestations. Patients were assigned to Group A (n = 8): expectant /symptoms-driven versus Group B (n = 4): protocol-driven. At S1P 7 had systemic-to-pulmonary shunt (SPS), 1 SPS with anomalous pulmonary venous return (APVR) repair (Group A) compared to 2 SPS, 1 SPS with APVR repair and 1 Norwood operation (Group B). Median duration from S1P to IMO was 82 days (range 57-336; Group A) compared to 14 days (range 11-31; Group B); p < 0.05. Median age at IMO was 87 days (range 8-345) [Group A: 99 days (range 68-345) vs Group B: 25 days (range 8-39)] (p < 0.05). Early SPS failure occurred in 25% (2 of 8) for Group A compared to none in Group B (p < 0.05). Hospital mortality following IMO was 25% [Group A: 37.5% (3 of 8) vs Group B: 0; p < 0.05]. Interstage survival was 67% [Group A: 50% (4 of 8) vs Group B: 100%; p < 0.05]. Time to SCPC following S1P was 186 days (range 169-218) for Group A compared to 118 days (range 97-161) (Group B); p < 0.05. Operative intervention for IM in SV/HS is associated with significant interstage attrition and might impact the time to SCPC. SPS is at risk for early failure after IMO. A comprehensive standardized concept can mitigate detrimental implications.

Pulmonary arteriovenous malformations in a patient with single ventricle and polysplenia syndrome

A 5-month-old girl with single ventricle, interrupted inferior vena cava and polysplenia syndrome palliated with bilateral Blalock-Taussig shunts developed severe cyanosis despite apparently increased pulmonary blood flow. Angiography revealed diffuse pulmonary arteriolar capillary dilatation and early pulmonary venous filling, suggesting the presence of pulmonary arteriovenous malformations. Abdominal angiography at 6 months demonstrated a large extrahepatic portosystemic shunt, which was percutaneously closed with a vascular plug. Kawashima operation was performed 2 weeks after portosystemic shunt closure. Although cyanosis improved temporarily, the patient suffered from deteriorating cyanosis at 9 months of age and underwent Fontan completion. Thereafter, her oxygen saturation gradually improved to 95% over the course of 3 weeks. Both the congenital extrahepatic portosystemic shunt and Kawashima operation contributed to the development of pulmonary arteriovenous malformations.

Concurrent right atrial isomerism, complete atrioventricular septal defect, and single ventricle in an L-transposition of great arteries patient complicated by brain abscess

We present a case of an 11-year-old Indonesian female who was referred to our facility after surgical excision of brain abscess. The patient has been previously diagnosed with right atrial isomerism, complete atrioventricular septal defect, and L-Transposition of great arteries. Multiple staged surgeries are required for the management of this condition.

Understanding Stage II Bidirectional Cavopulmonary Shunts

Despite improvements in surgical technique and medical management, single-ventricle lesions remain one of the most challenging congenital heart anomalies to treat, and mortality rates are high. Most infants who have single-ventricle palliation undergo a sequence of surgeries to optimize pulmonary and systemic blood flow. The first surgery to separate pulmonary and systemic blood flow is the bidirectional cavopulmonary shunt. This article describes single-ventricle lesions and gives a basic overview of outcomes and strategies to improve interstage mortality. Preoperative investigations that evaluate stage II candidacy are reviewed along with surgical approaches and postoperative physiology. Although mortality rates are low and decreasing in patients with bidirectional cavopulmonary shunts, morbidity is still a challenge. Nurses must understand the pertinent anatomy and physiology and recognize postoperative complications early in order to reduce morbidity. Postoperative complications, management, outcomes and nursing care are discussed.

Heterotaxy Syndrome and Intestinal Rotation Abnormalities

BACKGROUND

Infants with heterotaxy syndrome (HS) have abnormal lateralization of organs along the right-left body axis. Intestinal rotation abnormalities (IRAs) are a potential source of morbidity and mortality. For this study, our objective was to prospectively observe a cohort of infants with HS and determine the incidence and natural history of IRA.

METHODS

Infants ≤6 months of age with HS were enrolled in this prospective observational study. Exclusion criteria were other congenital abnormalities that necessitated abdominal surgery. HS was defined as any arrangement of organs that was not situs solitus or situs inversus along with associated congenital heart disease. The investigation for IRA was at the discretion of each participating center.

RESULTS

Infants were recruited from January 2012 to December 2016. Thirty-eight infants from 7 institutions were included; 22 infants had right isomerism and 16 infants had left isomerism. Twenty-nine infants (76%) were evaluated for IRAs; 21 of 29 evaluations (72%) were abnormal. Eight infants were investigated because of symptoms, and 21 infants were evaluated routinely. The median age at symptom presentation was 46 days (range: 5-171 days). Seven infants had a Ladd procedure; 4 were prophylactic, with 3 as part of a combined procedure, and 3 were emergent. No child suffered acute midgut volvulus over a median follow-up of 1.6 years (range: 0.06-4.93 years).

CONCLUSIONS

IRAs are common in infants with HS. Infants with symptoms presented by 6 months of age. There was no failure of expectant management resulting in midgut volvulus during a median follow-up of 1.6 years.

Atrioventricular canal defect and genetic syndromes: The unifying role of sonic hedgehog

The atrioventricular canal defect (AVCD) is a congenital heart defect (CHD) frequently associated with extracardiac anomalies (75%). Previous observations from a personal series of patients with AVCD and "polydactyly syndromes" showed that the distinct morphology and combination of AVCD features in some of these syndromes is reminiscent of the cardiac phenotype found in heterotaxy, a malformation complex previously associated with functional cilia abnormalities and aberrant Hedgehog (Hh) signaling. Hh signaling coordinates multiple aspects of left-right lateralization and cardiovascular growth. Being active at the venous pole the secondary heart field (SHF) is essential for normal development of dorsal mesenchymal protrusion and AVCD formation and septation. Experimental data show that perturbations of different components of the Hh pathway can lead to developmental errors presenting with partially overlapping manifestations and AVCD as a common denominator. We review the potential role of Hh signaling in the pathogenesis of AVCD in different genetic disorders. AVCD can be viewed as part of a "developmental field," according to the concept that malformations can be due to defects in signal transduction cascades or pathways, as morphogenetic units which may be altered by Mendelian mutations, aneuploidies, and environmental causes.

Clinical care for primary ciliary dyskinesia: current challenges and future directions

Primary ciliary dyskinesia (PCD) is a rare genetic disease that affects the motility of cilia, leading to impaired mucociliary clearance. It is estimated that the vast majority of patients with PCD have not been diagnosed as such, providing a major obstacle to delivering appropriate care. Challenges in diagnosing PCD include lack of disease-specific symptoms and absence of a single, “gold standard”, diagnostic test. Management of patients is currently not based on high-level evidence because research findings are mostly derived from small observational studies with limited follow-up period. In this review, we provide a critical overview of the available literature on clinical care for PCD patients, including recent advances. We identify barriers to PCD research and make suggestions for overcoming challenges.

Challenges in PCD must be overcome through international collaboration; networks must build on recent advanceshttp://ow.ly/4d4I30dXzWg

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.

Bradyarrhythmias in Congenital Heart Disease

Bradyarrhythmias in adults with congenital heart disease (CHD) comprise a complex group of arrhythmia disorders with congenital and acquired origins, highly variable long-term sequelae, and complicated treatment options. They can develop across the spectrum of CHD defects and can be encountered at all ages. Although permanent pacing is effective in treating bradyarrhythmias, it is associated with many complications and morbidity, where it is often used early in life. This section discusses the incidence and prevalence of bradyarrhythmias in the CHD population, their timing of occurrence with respect to specific disease entities and interventions, and their short- and long-term clinical sequelae.

Current Expectations for Cardiac Transplantation in Patients With Congenital Heart Disease

Congenital heart disease accounts for 40% of pediatric heart transplants and presents unique challenges to the transplant team. Suitability for transplantation is defined in part by degree of sensitization, pulmonary vascular resistance, and hepatic reserves. The incremental transplant risk for patients with congenital heart disease occurs within the first 3 months, after which survival is equivalent to transplantation for cardiomyopathy. Single ventricle with prior palliation, and especially the failing Fontan, carry the highest risk for transplantation and are least amenable to bridging with mechanical circulatory support. More effective bridging to transplant with mechanical circulatory support will require improvements in the adverse event profile of available pumps and the introduction of miniaturized continuous flow technology. The major barriers to routine long-term survival are chronic allograft failure and allograft vasculopathy. Despite these many challenges, continuing improvements in the care of pediatric heart transplant patients have pushed the median posttransplant survival past 15 years for children and to 20 years for infants.

Impact of Era, Type of Isomerism, and Ventricular Morphology on Survival in Heterotaxy: Implications for Therapeutic Management

BACKGROUND

Heterotaxy has been demonstrated to reduce survival. There are several different subgroups of patients, however, and no single study has had a large number of patients and analyzed survival across the different subgroups such as patients born in different eras, patients with right and left isomerism, and patients with biventricular or functionally univentricular hearts. This study pools previously reported data from Kaplan-Meier curves and performs such subgroup analysis.

METHODS

A systematic review of the literature was performed to identify studies reporting survival of patients with the so-called "heterotaxy" by means of Kaplan-Meier survival curves. Data were extracted from these survival curves and then pooled together. A polynomial regression was then used to generate a pooled survival curve. This was done for all patients, those born in a more recent era, those with right and left isomerism, and those with biventricular or functionally univentricular hearts.

RESULTS

Those born in the more recent era (after 2000) had increased survival compared to the overall cohort. Those with left isomerism tended to have a survival benefit compared to those with right isomerism until about 16 years of age, beyond which those with right isomerism developed a survival benefit. Those with biventricular hearts had a survival benefit compared to those with left isomerism.

CONCLUSION

Survival in the so-called heterotaxy syndrome is based on several factors, which include era of birth, sidedness of isomerism, and whether the heart is biventricular or functionally univentricular.

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.

Outcome of Glenn Anastomosis for Heterotaxy Syndrome with Single Ventricle

A retrospective study was undertaken of 157 patients who underwent a Glenn anastomosis between January 1996 and May 2001. Of these, 33 had heterotaxy syndrome: 20 males and 13 females, with a mean age of 1.26 ± 2.8 years. Twenty-five had right atrial isomerism and 5 had left isomerism. A common atrioventricular valve was found in 24 patients, 18 had bilateral superior venae cavae, and 18 had anomalous pulmonary venous return. Repair was carried out in 8 patients with anomalous pulmonary venous return, and pulmonary artery augmentation was performed in 11. Compared to the 124 patients who had a Glenn operation for single ventricle without heterotaxy, there were significantly longer durations of mechanical ventilation, intensive care unit stay, and inotropic support, as well as higher mortality in the heterotaxy group. Heterotaxy syndrome with single ventricle still has a high rate of morbidity and mortality. Patients with severe atrioventricular valve regurgitation are at risk of early death. Complete Fontan circulation may not be possible in all patients, and Glenn anastomosis may be their final palliation.

Surgical Outcome of Heterotaxy Syndrome in a Single Institution

Heterotaxy syndrome encompasses a wide range of anatomical variants including poor pulmonary vascular development. Surgical outcome remains poor in this difficult subgroup. Between April 1996 and November 2004, 27 patients with visceral heterotaxy were enrolled in this study. The median age at presentation was 25 days. There were 11 patients with asplenia and 16 with polysplenia. There were 5 deaths (4 in patients with asplenia, 1 in a patient with polysplenia). All patients with asplenia were scheduled for single-ventricle repair, and 5 completed a modified Fontan procedure. Of the 16 patients with polysplenia, 8 completed 2-ventricle repair and 6 had a modified Fontan. In polysplenia, actuarial survival was 93.8% at 4 months, and remained constant thereafter. In asplenia, survival was 81.8% at 1 month, and 53.0% at 1 year. A significant correlation was found between nonconfluent pulmonary arteries and mortality. The medium-term result in polysplenia was satisfactory, but not in asplenia. Nonconfluent pulmonary arteries carry a high risk of mortality, and a strategy to create pulmonary vascular confluence and satisfactory pulmonary blood flow is mandatory.

Heterotaxy Syndrome: Proceedings From the 10th International PCICS Meeting

A session dedicated to heterotaxy syndrome was included in the program of the Tenth International Conference of the Pediatric Cardiac Intensive Care Society in Miami, Florida in December 2014. An invited panel of experts reviewed the anatomic considerations, surgical considerations, noncardiac issues, and long-term outcomes in this challenging group of patients. The presentations, summarized in this article, reflect the current approach to this complex multiorgan syndrome and highlight future areas of clinical interest and research.