Pulmonary Versus Systemic Outflow Obstruction in Functionally Univentricular Hearts with Isomerism: An Observation.

Our objective was to review our experience with isomerism associated with univentricular hearts and evaluate the prevalence of pulmonary versus systemic outflow obstruction. We identified those prenatally or postnatally diagnosed, between September 2004 and October 2021, with right and left isomerism and a functionally univentricular heart. We identified 62, 51 prenatally and 11 postnatally. Of the 62, 61 had prenatal care for an 84% (51/61) prenatal detection rate. Of the 62, 36 (58%) had right isomerism. Of the 51 prenatally diagnosed, 36 were live-born, 13 had fetal demise, and two underwent elective termination. Of the total 62, 43 had pulmonary outflow obstruction, 14 had systemic outflow obstruction, three had no outflow obstruction, and two had a common arterial trunk. However, between September 2004 and December 2019, 41 of 52 (79%) had pulmonary outflow obstruction, and between January 2000 and October 2021, 2 of 10 (20%) had pulmonary outflow obstruction (p = 001). We noted a statistically significant temporal change in the prevalence of pulmonary versus systemic outflow obstruction in those with isomeric situs and a functionally univentricular heart. Further, prenatal diagnosis exceeded 80% in the general population of Nevada.

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.

Analysis of outcomes in patients with abnormal laterality undergoing congenital heart surgery.

OBJECTIVE: Laterality anomalies are almost always associated with severe cardiac anomalies. Demographic properties, type of the procedures, associated anomalies, and early and mid-term prognosis of four types of laterality anomalies were analysed. METHODS: A total of 64 consecutive patients with laterality anomalies were enrolled between July 2014 and July 2020. We grouped the patients as situs solitus dextrocardia (SSD) (n = 12; 18.7%); situs inversus (SI) (n = 16; 25%); right atrial isomerism (RAI) (n = 29; 45.3%); and left atrial isomerism (LAI) (n = 7; 10.9%). TAPVC was only present in the RAI group (31%). Incidence of mitral or tricuspid atresia was higher in the SSD group (25%). All the patients were followed up with a mean of 19.06 ± 17.6 (0.1-72) months. RESULTS: Early postoperative mortality was 17 patients, among 107 procedures (15.8%). Twelve patients were in the neonatal period. All ten patients survived after isolated ductal stenting. Fourteen of the deaths were in the RAI group (48.3%). The 3-year survival rates were 85% in LAI, 78.7% in SI, 55.8% in SSD, and 38% in RAI groups. According to the multivariable Cox regression model, mechanical ventilation, kidney injury, RAI, and complex surgery in the neonatal period were independent risk factors for early mortality. CONCLUSION: Laterality anomalies are one of the most challenging patients who commonly had univentricular physiology. The most prevalent anomaly was RAI, and RAI had the worst outcome and survival. Ductal stent is an acceptable first intervention during the neonatal period in suitable patients. Complex procedures may carry a high risk of death in the neonatal period.

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.

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).

Prenatal diagnosis of caudal regression with heterotaxy syndrome: "A mermaid with a broken heart".

Caudal regression syndrome (CRS) is a rare congenital malformation with varying degrees of early gestational developmental failure. It is characterized by agenesis of the sacrum and lumbar spine, with lower limb neurological deficit and accompanying deformities of the pelvis, lower extremities, genitourinary, and gastrointestinal systems. We report a case of CRS associated with rare complex congenital heart defect, that is, heterotaxy syndrome, diagnosed prenatally.

Thoraco-Abdominal Abnormalities in Bardet-Biedl Syndrome: Situs Inversus and Heterotaxy.

OBJECTIVES: To characterize the diversity and prevalence of thoraco-abdominal abnormalities in Bardet-Biedl syndrome (BBS), a model ciliopathy for understanding the role of cilia in human health. STUDY DESIGN: The Clinical Registry Investigating BBS, a worldwide registry exploring the phenotype and natural history of BBS, was used to conduct the study. Protected health information was obtained by subject or family interview and Health Insurance Portability and Accountability Act-approved release of data including imaging studies and genetic testing. Echocardiography and imaging findings were independently confirmed by 2 cardiologists. RESULTS: Thoraco-abdominal abnormalities were identified in 6 of 368 (1.6%) subjects with a minimum prevalence of 1 in 60 Clinical Registry Investigating BBS participants. Diverse laterality defects were observed suggesting that the underlying ciliopathy randomly alters embryonic left-right axis orientation. Congenital heart disease, common in heterotaxy, was present in 2 subjects. Additional defects, uncommonly reported in BBS, were observed in the central nervous, genitourinary, gastrointestinal, and musculoskeletal systems in the subjects. No BBS genotype was favored in the cohort. One subject had genetic and clinical phenotype diagnostic of both primary ciliary dyskinesia and BBS. CONCLUSIONS: The variety of thoraco-abdominal abnormalities in BBS suggests the pleiotropic nature of these anomalies is not confined to a single pattern or genotype. Clinicians providing care to individuals with BBS should consider the increased prevalence of thoraco-abdominal anomalies in BBS. Individuals with features suggestive of other ciliopathies, such as primary ciliary dyskinesia, should undergo further evaluation for additional genetic disorders. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02329210.

Inflammation, Active Fibroplasia, and End-stage Fibrosis in 172 Biliary Atresia Remnants Correlate Poorly With Age at Kasai Portoenterostomy, Visceral Heterotaxy, and Outcome.

Published histologic studies of the hilar plate or entire biliary remnant at the time of Kasai portoenterostomy (KHPE) have not provided deep insight into the pathogenesis of biliary atresia, relation to age at surgery, prognosis or the basis for successful drainage. We report detailed histologic findings in 172 centrally reviewed biliary remnants with an average of 6 sections per subject. Active lesions were classified as either necroinflammatory (rare/clustered in a few subjects) or active concentric fibroplasia with or without inflammation (common). Inactive lesions showed bland replacement by collagen and fibrous cords with little or no inflammation. Heterogeneity was common within a given remnant; however, relatively homogenous histologic patterns, defined as 3 or more inactive or active levels in the hepatic ducts levels, characterized most remnants. Homogeneity did not correlate with age at KHPE, presence/absence of congenital anomalies at laparotomy indicative of heterotaxy and outcome. Remnants from youngest subjects were more likely than older subjects to be homogenously inactive suggesting significantly earlier onset in the youngest subset. Conversely remnants from the oldest subjects were often homogenously active suggesting later onset or slower progression. More data are needed in remnants from subjects <30 days old at KHPE and in those with visceral anomalies. Prevalence of partially preserved epithelium in active fibroplastic biliary atresia lesions at all ages suggests that epithelial regression or injury may not be a primary event or that reepithelialization is already underway at the time of KHPE. We hypothesize that outcome after KHPE results from competition between active fibroplasia and reepithelialization of retained, collapsed but not obliterated lumens. The driver of active fibroplasia is unknown.

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.

Neonatal Outcomes in Total Anomalous Pulmonary Venous Return: The Role of Prenatal Diagnosis and Pulmonary Venous Obstruction.

The objective of this study is to evaluate neonatal outcomes of total anomalous pulmonary venous return (TAPVR) and identify fetal echocardiography findings associated with preoperative pulmonary venous obstruction (PPVO). This retrospective study evaluated TAPVR cases from 2005 to 2014 for preoperative and postoperative outcomes based on prenatal diagnosis, PPVO, and heterotaxy syndrome. Fetal pulmonary and vertical vein Dopplers were analyzed as predictors of PPVO. Of 137 TAPVR cases, 12% were prenatally diagnosed; 60% had PPVO, and 21% had heterotaxy. Of the prenatally diagnosed patients, 63% also had heterotaxy. TAPVR repair was performed in 135 cases and survival to discharge was 82% (112/137). Heterotaxy was the only independent predictor of mortality on multiple regression analysis [OR 5.5 (CI 1.3-16.7), p = 0.02]. PPVO was associated with preoperative acidosis, need for inhaled nitric oxide, and more emergent surgery, but not postoperative mortality. Fetal vertical vein Doppler peak velocity > 0.74 m/s mmHg predicted PPVO (93% sensitivity; 83% specificity) while pulmonary vein Doppler did not. TAPVR has severe neonatal morbidity and mortality with low prenatal diagnosis rates in the absence of heterotaxy. Patients with obstructed TAPVR had greater preoperative morbidity, but only heterotaxy was independently associated with increased postoperative mortality. Vertical vein velocity helped prenatally identify those at risk of PPVO.

Long-term outcome of patients with right atrial isomerism after common atrioventricular valve plasty.

OBJECTIVES: To review long-term outcomes of patients with right atrial (RA) isomerism who underwent common atrioventricular valve (CAVV) plasty. METHODS: We retrospectively analysed 59 patients with RA isomerism operated on between January 2004 and April 2016. We divided patients into those with CAVV plasty (CAVV plasty (+), 29 patients) and without CAVV plasty (CAVV plasty (-), 30), and we compared the outcome between the groups. We further divided patients into those with CAVV plasty before bidirectional cavopulmonary shunt (BCPS) operation (group before BCPS, 13 patients) or CAVV plasty with or after BCPS (group with or after BCPS, 16), and we compared the outcome between these groups. We reviewed the outcomes of 7 neonatal patients who underwent CAVV plasty. RESULTS: Kaplan-Meier estimated survival rates at 10 years were 70 ± 10% and 69 ± 9% in the CAVV plasty (+) and CAVV plasty (-) groups, respectively ( P = 0.45). Kaplan-Meier estimated survival rates at 10 years were 47 ± 17% and 85 ± 10% in the group before BCPS and group with or after BCPS, respectively ( P = 0.01). Among 7 neonates in the group before BCPS, 4 are alive; Kaplan-Meier estimated survival rates at 1 year and 5 years were 60 ± 20% and 30 ± 24%, respectively. CONCLUSIONS: Patients who underwent CAVV plasty with or after BCPS had good outcomes; the outcome of patients with CAVV plasty was the same as that of those without CAVV plasty. Treatment for patients who require CAVV plasty before BCPS, especially neonates, is challenging.

When the right (Drug) should be left: Prenatal drug exposure and heterotaxy syndrome.

BACKGROUND: Recent studies reported an association between prenatal propylthiouracil exposure and birth defects, including abnormal arrangement across the left-right body axis, suggesting an association with heterotaxy syndrome. METHODS: This case-control and case-finding study used data from 1981 to 2013 from the EUROCAT birth defect registry in the Northern Netherlands. First, we explored prenatal exposures in heterotaxy syndrome (cases) and Down syndrome (controls). Second, we describe the specific birth defects in offspring of mothers using propylthiouracil (PTU) prenatally. RESULTS: A total of 66 cases with heterotaxy syndrome (incidence 12.1 per 100,000 pregnancies) and 783 controls with Down syndrome (143.3 per 100,000 pregnancies) were studied. No differences in intoxication use during pregnancy were found between cases and controls, including smoking (28.0% vs. 22.7%; p = 0.40), alcohol (14.0% vs. 26.9%; p = 0.052), and recreational drugs (0 vs. 0.3%; p = 1.00). We found an association between heterotaxy syndrome and prenatal drug exposure to follitropin-alfa (5.6% vs. 1.1%; p = 0.04), and drugs used in nicotine dependence (3.7% vs. 0.2%; p = 0.02). Five mothers used PTU during pregnancy and gave birth to a child with trisomy 18, renal abnormalities, or hypospadias and cardiac defects. CONCLUSION: This study identified follitropin-alfa and drugs used in nicotine dependence as possible teratogens of heterotaxy syndrome. Our data suggest the possibility that there is an increased risk of birth defects (including renal, urological, and cardiac abnormalities) in children born among mothers taking PTU prenatally, but not for heterotaxy syndrome. Birth Defects Research (Part A) 106:573-579, 2016. © 2016 Wiley Periodicals, Inc.

Acute Myocardial Infarction in Adult Congenital Patients with Bodily Isomerism.

INTRODUCTION: Children born with congenital malformations of the heart are increasingly surviving into adulthood. This population of patients possesses lesion-specific complication risks while still being at risk for common illnesses. Bodily isomerism or heterotaxy, is a unique clinical entity associated with congenital malformations of the heart which further increases the risk for future cardiovascular complications. We aimed to investigate the frequency of myocardial infarction in adults with bodily isomerism. METHODS: We utilized the 2012 iteration of the Nationwide Inpatient Sample to identify adult inpatient admissions associated with acute myocardial infarction in patients with isomerism. Data regarding demographics, comorbidities and various procedures were collected and compared between those with and without isomerism. RESULTS: A total of 6,907,109 admissions were analyzed with a total of 172,394 admissions being associated with an initial encounter for acute myocardial infarction. The frequency of myocardial infarction did not differ between those with and without isomerism and was roughly 2% in both groups. Similarly, the number of procedures and in-hospital mortality did not differ between the two groups. CONCLUSIONS: The frequency and short-term prognosis of acute myocardial infarction is similar in patients with and without isomerism.

Screening and Treatment of Intestinal Rotational Abnormalities in Heterotaxy: A Systematic Review and Meta-Analysis.

OBJECTIVE: To assess the role of screening and prophylactic surgery for intestinal rotational abnormalities (IRAs) in asymptomatic patients with heterotaxy. STUDY DESIGN: PubMed, Embase, and Cinahl were searched electronically to determine the overall incidence of IRAs in heterotaxy; the detection rate of IRAs associated with screening; the incidence of midgut volvulus in patients without screening; and the incidence of morbidity and mortality after prophylactic and emergency Ladd procedures. Relevant data were computed with a meta-analysis of proportions. Between-study heterogeneity was assessed with the I(2) statistic. RESULTS: From 276 papers identified, 24 studies with a total of 1433 patients with heterotaxy were included for systematic review. No randomized study was identified. True incidence of IRA in heterotaxy could not be ascertained through meta-analysis. In patients who underwent screening, the incidence of IRA was 58%. Acute midgut volvulus occurred in 5.8% of those who did not undergo screening. Postoperative mortality after Ladd procedure mainly was associated with cardiac insufficiency, and overall it was significantly greater in the emergency group compared with the prophylactic group (18% vs 5.6%). The complication rate also was greater in case of emergency vs prophylactic abdominal surgery (27% vs 16%); adhesional small bowel obstruction was the most common complication overall (6%). CONCLUSION: The screen-detected incidences of IRA and acute midgut volvulus were significantly greater in heterotaxy than the normal population. Prophylactic Ladd procedure was associated with less morbidity and mortality compared with emergency surgery. A long-term prospective randomized trial is needed to define the indication for screening and prophylactic treatment of IRA in heterotaxy.

Abnormalities of Fetal Situs: An Overview and Literature Review.

The incidence of congenital heart disease is most commonly reported in 8 per 1000 live births. Situs anomalies are among the least common forms of congenital heart disease. This study defines situs and describes the variations of fetal situs anomalies. Situs refers to the arrangement of the viscera, atria, and vessels within the body. Situs solitus describes the normal arrangement; situs inversus describes inverted arrangement of the viscera and atria; and situs ambiguous (also referred to as heterotaxy) describes disturbances in arrangements that can neither be identified as solitus nor inversus. This review will concentrate on heterotaxy, as it is the most complicated situs abnormality to define, classify, and study. Prognosis of heterotaxy is variable but most correlated with cardiac anatomy. Management is concentrated on numerous cardiac operations and requires a multidisciplinary approach to address coexisting congenital anomalies.

Heterotaxy Polysplenia Syndrome In An Adult With Unique Vascular Anomalies: Case Report With Review Of Literature.

The pattern of anatomical organization of the thoraco-abdominal visceral and vascular structures which is not the expected normal arrangement, is called as situs ambiguous or heterotaxy syndrome. Patients with heterotaxy syndrome exhibit a wide spectrum of anatomical variations involving thoraco-abdominal structures. We present here an incidental finding of heterotaxy syndrome associated with unique vascular anomalies in a 35 year old male patient evaluated initially for nephrolithiasis by ultrasonography, and intravenous pyelography. Further evaluation by multidetector row computed tomography showed bilateral bilobed lungs with hyparterial bronchi, cardiac apex to the left, five branches from left-sided aortic arch with retroesophageal right subclavian artery, interrupted inferior vena cava with azygos continuation, left renal vein continuing as hemiazygos vein and replaced common hepatic artery arising from the superior mesenteric artery. Other vascular anomalies include right internal iliac vein joining the left common iliac vein and precaval course of the single main right renal artery. Anomalies involving abdominal organs include right-sided stomach, midline liver, multiple splenules (polysplenia) in right upper quadrant of abdomen, short truncated pancreas, intestinal malrotation, inversion of superior mesenteric vessels and a preduodenal portal vein. To the best of our knowledge this is the first report of association of left renal vein continuing as hemiazygos vein, precaval right renal artery and anomalous branching pattern of aortic arch with heterotaxy syndrome.

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.