Right Atrial Isomerism Research Articles

The Clinical Outcomes in Patients With Atrial Isomerism Undergoing Single Ventricular Palliation: Insights From A Single-Center Study in Thailand.

Background: The management of atrial isomerism across various countries may impact survival outcomes. Methods: This retrospective study involved patients diagnosed with atrial isomerism undergoing single ventricular palliation between 2000 and 2021. The objective was to evaluate survival outcomes within the right atrial isomerism (RAI) and left atrial isomerism (LAI) groups, as well as overall survival. Results: Of the 125 patients diagnosed with atrial isomerism, 105 (84%) had RAI, and 20 (16%) had LAI. The median age at presentation was 3 days (range: birth to 7.1 years), with median follow-up of 6.6 years (range: 0.59 months to 30.8 years). In the overall cohort, survival rates at one, five, and ten years were 85.6%, 72.3%, and 66.8%, respectively, with no statistically significant difference between RAI and LAI groups (log rank P value = .293). Specifically, survival rates in the RAI group at one, five, and ten years were 83.8%, 69.0%, and 62.6%, respectively, while in the LAI group, there were 95.0%, 89.7%, and 81.6%, respectively. Following the third-stage operation, overall survival rates at one and five years were 76.4% and 76.4%, respectively. Among patients in the RAI group, survival rates at one and five years post-third stage operation were 80.2% and 80.2%, respectively. Conclusions: Despite resource limitations, the survival outcomes of patients with atrial isomerism were found to be similar with those observed in high-income countries. Although an increased mortality rate was noted within the first year of life, focusing efforts on neonatal and infant care holds potential for improving overall outcomes.

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.

Outcomes of treatment for right atrial isomerism with functional single ventricle and extracardiac total anomalous pulmonary venous connection beyond neonatal period: Delayed surgical treatment, improving outcomes.

Total anomalous pulmonary venous connection (TAPVC) is frequently associated with right atrial isomerism (RAI), which is commonly complicated with an unbalanced atrioventricular canal with contralateral hypoplasia, complex systemic and pulmonary venous anatomy, and conotruncal abnormalities, resulting in increased risk of mortality. This study aimed to review the outcomes of delayed surgical treatment for patients with RAI complicated with functional single ventricle (FSV) and TAPVC at a single center. In this retrospective study, we reviewed the medical records of 24 consecutive patients with RAI complicated with FSV and TAPVC who underwent initial surgical palliation after 5-month old between September 2008 and June 2019. Demographic data, concomitant anomalies, age at initial palliation, and surgical interventions were extracted and analyzed using the Cox proportional hazard model to assess risk factors for mortality and the Kaplan-Meier method to assess survival. The in-hospital mortality was 12.5% (three out of 24). The causes of death were pulmonary arterial hypertension and low cardiac output syndrome. Average follow-up was 65.2 ± 40.3 months (7-137 months). Another 4 patients died during the follow-up due to low cardiac output syndrome, protein-losing enteropathy and pulmonary arterial hypertension, respectively. Kaplan-Meier estimated survival at 1 and 5 years were 83.1 and 69.4%, respectively. Fontan completion was 45.8% (11/24). The mortality for patients with pulmonary venous obstruction (PVO) was 66.7% (4/6). Cox multivariate regression analysis indicated that preoperative PVO was the only risk factor for mortality (p = 0.032; hazard ratio, 10.000; CI 1.222-81.811). Outcomes of delayed surgical treatment for patients with RAI complicated with FSV and TAPVC have improved significantly. The survival and Fontan completion were higher. However, preoperative PVO was still the risk factor for mortality.

Prenatal diagnosis of total anomalous pulmonary venous connection using 2D and HDlive flow combined with spatiotemporal image correlation.

The objective of this study is to examine the application value of two-dimensional (2D) and high-definition live (HDlive) flow combined with spatiotemporal image correlation (STIC) in diagnosing fetal total anomalous pulmonary venous connection (TAPVC). Seventeen cases of fetal TAPVC were diagnosed using 2D and HDlive Flow combined with STIC. These cases were then retrospectively analyzed to examine the value of using 2D and HDlive Flow combined with STIC in the diagnosis of TAPVC. 2D and HDlive Flow combined with STIC detected 13 cases of supracardiac TAPVC (two isolated cases, seven cases with right atrial isomerism (RAI), four cases with other complex malformations), one case of isolated intra-cardiac TAPVC, and three cases of cardiac TAPVC (two isolated cases and one case with complex congenital heart anomaly). Small left atrium (LA), the absence of PVs drainage into the LA and the increased retroatrial distance between LA and the descending aorta (DAo) were significant signs that should raise the suspicion of fetal TAPVC. HDlive Flow combined with STIC can dynamically display the TAPVC which may assit the prenatal diagnosis of TAPVC. 2D and HDlive Flow combined with STIC can assit the diagnosis of fetal TAPVC abnormalities and has important clinical value.

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

ObjectiveCardiac 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.MethodsFetuses 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.ResultsA 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.ConclusionHeterotaxy 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.

Heterotaxy syndrome: Prenatal diagnosis, concomitant malformations and outcomes.

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

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

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. 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. 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. 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.

BIDIRECTIONAL GLENN SHUNT AND REPAIR OF TOTAL ANOMALOUS PULMONARY VENOUS CONNECTION IN A 3 YEARS OLD CHILD WITH HETEROTAXY SYNDROME: A CASE REPORT

Right Atrial Isomerism (RAI) and total anomalous pulmonary venous connection (TAPVC) is a rare condition with very high mortality in neonatal period, but outcomes may be better in older children. A cyanotic 3 years old boy with dyspnea and growth retardation diagnosed with RAI and supracardiac type of TAPVC undergone a successful repair of TAPVC and simultaneous Glenn shunt. Older patients with RAI may be a distinct, more suitable group for surgical repair.

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

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. 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. 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. 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.

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

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. 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. 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). 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.

Twin atrioventricular nodes, arrhythmias, and survival in pediatric and adult patients with heterotaxy syndrome

Heterotaxy syndrome is likely to involve arrhythmias from associated conduction system abnormalities, which are distinct in different subtypes of isomerism and may change further after interventions and remodeling. The purpose of this study was to understand the risk of arrhythmias and its relation to isomerism subtypes. Patients diagnosed between 1980 and 2019 as having heterotaxy syndrome were enrolled and grouped as right atrial isomerism (RAI), left atrial isomerism (LAI), or indeterminate isomerism. Of the 366 patients enrolled, 326 (89.1%) had RAI, 35 (9.6%) LAI, and 5 (1.4%) indeterminate isomerism; 71 (19.4%) patients were adults. Arrhythmias occurred in 37.2% of patients (109 supraventricular tachycardia [SVT], 8 atrial fibrillation/flutter, 12 ventricular tachycardia, and 14 paced bradycardia). Freedom from arrhythmias by the age of 1, 5, 10, 20, and 40 years was 0.849, 0.680, 0.550, 0.413, and 0.053, respectively. Twin atrioventricular nodes were identified in 51.5% of patients with RAI, 8.7% of patients with LAI, and 40.0% of patients with indeterminate isomerism and were the key predictors of SVT. Indeterminate isomerism was also a risk factor for SVT. Other forms of tachycardia appeared relatively late. Sinus bradycardia with junctional rhythm was common in LAI (48.7%) and less in indeterminate isomerism (20.0%), with none occurring in RAI. Only in patients with RAI who showed the poorest survival, ventricular tachycardia worsened the long-term survival. RAI was the predominant subtype of heterotaxy in this cohort. Collectively, the median RAI/LAI ratio was 0.731 and 5.450 in Western and East Asian studies, respectively. Arrhythmias, tachycardia, or paced bradycardia were common, but the spectrum was distinct among subtypes.

Surgical Management of Heterotaxy Syndrome: Current Challenges and Opportunities.

Heterotaxy syndrome presents a unique challenge in surgical management, even in the current era. We hypothesized that certain anatomic subsets merit novel strategies. We analyzed morphologic details, surgeries, comorbidities, subsequent admissions, and survival using Kaplan-Meier methods and multivariable risk models from a single-institution experience of 103 consecutive patients with heterotaxy who underwent cardiac surgery between January 1, 1990, and May 31, 2016. Of the 103 patients (50 males and 53 females), 31 had left atrial isomerism, 64 had right atrial isomerism (RAI), and 8 patients' isomerism was indeterminate (IND), with first cardiac operation at a mean 1.0 year (standard deviation ±3.0 years) of age. Kaplan-Meier overall survival estimate was 83.1% at six months, 77.8% at one year, 65.9% at five years, and 52.1% at ten years. Survival was particularly low among RAI following repair of total anomalous pulmonary venous connection (TAPVC) at first operation, with one- and five-year survival of 57% and 46%, respectively. By multivariable analysis, the only risk factor for death during the early phase (hazard model) was repair of TAPVC at the first cardiac operation (hazard ratio [HR]: 4.4, P = .01), and risk factors during the longer term constant phase were atrioventricular valve (AVV) regurgitation (HR: 4.2, P < .01), male gender (HR: 3.7, P < .01), and two-ventricle repair (HR: 3.0, P = .02). Patients with heterotaxy undergoing the Fontan procedure had excellent subsequent survival (85% at ten years). This analysis of over 100 patients with heterotaxy identified TAPVC requiring initial repair as the major risk factor for early death and important AVV regurgitation as the major risk factor in the longer term. Survival with RAI and early repair of TAPVC were poor, with one-year mortality exceeding 40%. Patients with single ventricle completing the Fontan operation enjoyed outstanding ten-year survival (85%). Initial management of RAI requiring early repair of TAPVC remains challenging. For this high-risk subset, alternative strategies such as early referral for cardiac transplantation evaluation warrant consideration.

Pulmonary venous obstruction after extracardiac total cavopulmonary connection in right atrial isomerism.

Patients with functional single ventricle and right atrial isomerism (RAI) often have multiform cardiac pulmonary venous (PV) connection, which could be a risk factor for pulmonary venous obstruction (PVO) after extracardiac total cavopulmonary connection (EC-TCPC) owing to compression of the conduit. To investigate the anatomical risk factors for PVO after EC-TCPC in RAI. Twenty-nine patients with RAI without extracardiac total anomalous pulmonary venous connection were enrolled. No patients had PVO before EC-TCPC. A total of 14 and 15 patients had PV orifices ipsilateral and contralateral to the extracardiac conduit, respectively. The former 14 patients were assigned to two groups based on development of PVO after EC-TCPC (groups O and N). The pre- and post-operative cardiac morphologies and their relationship with the conduit were compared. After the EC-TCPC, the pressure gradients between the atrium and the PV were 5.0 ± 2.5 and 0.44 ± 0.2mmHg in groups O and N, respectively (p < 0.01); however, the pressure gradients in the left and right PVs were not significantly different, suggesting stenosis of the common PV orifice. The ratio of the horizontal distance from the vertebrae to the PV orifice and to the lateral edge of the atrium was significantly higher (0.38 ± 0.2 vs. 0.17 ± 0.1; p = 0.04) and the orifice was smaller (8.9 ± 2.0 vs. 15 ± 4.7mm; p < 0.01) in group O than in group N. In cases with ipsilateral locations of the conduit and PV orifice, small size and more lateral location of the PV orifice may be preoperative risk factors for development of PVO.

P4649Whole exome sequencing and whole genome sequencing improves genetic diagnosis of fetals with heterotaxy syndrome revealed by prenatal ultrasound

Abstract Background Heterotaxy (Htx) syndrome is an congenital disorders resulting from incorrectly establishment of left-right patterning during embryogenesis. Over 96% of patients with Htx exhibit some form of congenital heart disease (CHD),and has relatively poor survival. Multiple lines of evidence support genetic contributions to the etiology of Htx. As a specific genetic etiology is currently identifiable in only a minority of patients, there remains enormous potential for novel gene and pathway discovery. Purpose The aim of this study was to investigate the diagnostic yield of whole-exome sequencing (WES) and whole-genome sequencing (WGS) in fetuses with the pathogenesis of Htx, to explore candidate genes for Htx and to expand the clinical phenotype of known genetic conditions. Method WES and WGS were performed on specimens from 46 fetuses diagnosed with Htx and their parents. The single-nucleotide variants (SNVs) and copy-number variants (CNVs) were filtered and annotated by standard analysis process. All reported variants were classified according to he American College of Medical Genetics and Genomics guidelines. Results In the 46 fetuses, the detection rates of pathogenic and likely pathogenic variations were21.7% (10/46) and 10.9% (5/46) respectively. Ten pathogenic variations were identified on genes of CCDC114, DNAH11, ARMC4, STRA6, PQBP1 (hemizygote), HYDIN, RAI1 (Alagille Syndrome), ZFMP2 and Del(22q11.2) Syndrome. Five likely pathogenic variation were on DNAAF1 (Holshner syndrome), NF1, NEXN, NOTCH3 and FOXC1. Of 30 fetuses with prenatally diagnosed right atrial isomerism (RAI), the main intracardiac anomalies were atrioventricular canal (AV canal), isomerism of right atrial appendages, pulmonary stenosis or atresia (PS &amp; PA) and right aortic arch. In 16 fetuses diagnosed left atrial isomerism (LAI) the main intracardiac anomalies were isomerism of left atrial appendages, interrupted IVC and azygos vein continuation. Of the 10 positive cases, 8 fetus were diagnosed of RAI and 2 were diagnosed of LAI by prenatal ultrasonic examination or fetal autopsy. The detection rate was 8/30 (26.7%) for RAI and 2/16 (12.5%) for LAI. Conclusion This study outlines the way for a substantial improvement in the diagnostic yield of prenatal genetic disorders in Htx through WES and WGS. Our experience also expanded the knowledge of the clinical phenotype of known genetic conditions. Our results indicate that the proportion of SNV in Htx of prenatal cases was significantly higher than that in patients with other congenital heart abnormalities, and the recessive inheritance occurred in a higher proportion in Htx. Our results have important implications for clinical management and genetic counseling of Htx. Acknowledgement/Funding Ministry of Science and Technology of the People's Republic of China

Fetal pulmonary atresia with ventricular septal defect: echocardiographic findings, associated anomalies and chromosomal characteristics

Objective To analyze the echocardiographic findings, associated anomalies and chromosomal characteristics in fetuses with pulmonary atresia with ventricular septal defect (PA/VSD). Methods The echocardiographic data and follow-up materials were retrospectively reviewed in 30 256 fetuses from December 2012 to March 2018 in the consultation center of fetal heart disease in maternal-fetal medicine in Anzhen hospital. Of all the fetuses, 59 cases (0.19%) had PA/VSD. The echocardiographic findings, associated anomalies and chromosomal characteristics were retrospectively analyzed in all the 59 fetuses with PA/VSD. Based on whether the presence of the native pulmonary arteries and the major aortopulmonary collateral arteries (MAPCAs) or not, the PA-VSD was classified into type A, type B, and type C. Results A large ventricular defect was demonstrated in five-chamber view with 61.7% of the mean ratio of the aortic overriding. Other fetal echocardiographic features of all the 59 fetuses with PA/VSD included: the right aortic arch (n=19), reversal flow in the ductus arteriosus (n=40), MAPCAs (n=24). The classification of the PA/VSD included: type A (n=35), type B (n=5) and type C (n=19). Associated anomalies: persistent left superior vena cava (n=13), anomalous pulmonary vein connection (n=5), complete atrioventricular septal defect (n=5); single umbilical artery (n=3), right atrial isomerism (n=3). Of all the 30 cases performed chromosomal test, 3 cases had aneuploidy and 7 cases had microdeletion of chromosome. Conclusions The fetal echocardiographic findings of the PA/VSD are characteristic. For prenatal diagnosis of PA/VSD, the type of PA/VSD should be defined and chromosomal test should be performed, which can be helpful for prenatal consulting. Key words: Echocardiography; Heart septal defect, ventricular; Pulmonary atresia; Prenatal diagnosis; Chromosomal aberrations

Cardiac Rhythm Disturbances in Heterotaxy Syndrome.

Heterotaxy syndrome is associated with complex cardiac malformations and cardiac conduction system abnormalities. Those with right atrial isomerism (RAI) have dual sinus nodes and dual atrioventricular nodes predisposing them to supraventricular tachycardia (SVT). Those with left atrial isomerism (LAI) lack a normal sinus node and are at risk of sinus node dysfunction (SND) and atrioventricular block (AV block). We report the occurrence and risk factors associated with arrhythmias in heterotaxy syndrome. A retrospective review of all heterotaxy syndrome patients born and treated at our institution between 2000 and 2014 was performed. A total of 40 patients were identified; 16/40 (40%) with LAI and 24/40 (60%) with RAI. There were 12 deaths during follow-up [LAI 3/16 (19%), RAI 9/24 (38%); p = 0.30]. Twenty-one patients had arrhythmias during a mean follow-up period of 5.4 years; 14/16 (87%) in LAI and 7/24 (29%) in RAI (p < 0.001). Freedom from arrhythmia at 1,3,5years of age was 75.0%, 37.9%, 22.7% in LAI, and 83.3%, 77.5%, 69.6% in RAI, respectively(p = 0.00261). LAI had a three-fold increase in developing arrhythmias. Left atrial isomerism was the only factor identified to be associated with arrhythmia occurrence. Arrhythmias were commonly seen in heterotaxy syndrome particularly in left isomerism with more than half of the patients having arrhythmias by 3years of age. Atrial situs was the only risk factor identified to be associated with arrhythmias, and close follow-up is warranted in these patients.

Analysis of cardiovascular misinterpretations of prenatal ultrasound diagnosis in fetuses with heterotaxia syndrome

Objective To explore the correlation between the cardiovascular ultrasound results and pathological findings of heterotaxia syndrome, analyze the cause of the difference, and improve the prenatal cardiovascular diagnostic accuracy of heterotaxia syndrome by ultrasound. Methods According to fetal autopsy or vessel casting, the ultrasound results of 37 fetuses with heterotaxia syndrome were retrospectively analyzed. The cardiovascular misinterpretations of ultrasound were summarized in the venous-atrial segment, atrial-ventricular segment and ventricular-arterial segment. Results ①Thirty fetuses underwent autopsy and seven fetuses vessel casting were included, there were 10 fetuses with left atrial isomerism and 27 fetuses with right atrial isomerism.Only one left isomerism was misdiagnosed and the diagnostic accuracy of atrial isomerism by ultrasound was 97.3%. ②Thirty-seven fetuses with heterotaxia syndrome included 206 cardiovascular malformations. Twenty-seven misinterpretations of ultrasound were found and the rate of cardiovascular misinterpretations was 13.1%. ③The cardiovascular misinterpretations of left atrial isomerism involved 1 secondary atrial septal defect in the atrial-ventricular segment and 1 aortic atresia, 2 anomalous position of arterial duct in the ventricular-arterial segment. ④The cardiovascular misinterpretations of right atrial isomerism in the venous-atrial segment included 4 common pulmonary vein atresia, 3 anomalous hepatic venous connection, 3 total abnormal pulmonary venous drainage, 2 persistent left superior vena cava and 2 abnormal inferior cava venous drainage. The cardiovascular misinterpretations of right atrial isomerism in the atrial-ventricular segment contained 2 secondary atrial septal defect, 1 unroofed coronary sinus and 1 partial atrioventricular septal defect. The cardiovascular misinterpretations of right atrial isomerism in the ventricular-arterial segment involved 3 double-outlet right ventricle, 1 truncus arteriosus and 1 anomalous position of arterial duct. Conclusions The correspondence between ultrasound results and pathological findings about cardiovascular malformations of heterotaxia syndrome is high. The most common cardiovascular misinterpretations of left atrial isomerism involve the ventricular-arterial segment. And the most common cardiovascular misinterpretations of right atrial isomerism involve the venous-atrial segment. Key words: Ultrasonography, prenatal; Heart defects, conginatal; Heterotaxia syndrome

Prenatal ultrasound diagnosis of unroofed coronary sinus and review of the literature

Objective To summarize the prenatal ultrasonographic characteristics of unroofed coronary sinus(URCS) for improving the prenatal echocardiography diagnostic accuracy of URCS. Methods The retrospective review for prenatal ultrasonogram of 7 fetuses was applied, which were diagnosed as URCS. The prenatal ultrasonographic characteristics of 7 fetuses with URCS were reviewed and comparatively analyzed with postpartum autopsy findings or postnatal echocardiography. The relevant literatures referring to the prenatal diagnosis of URCS were reviewed. The experience of prenatal diagnosis of URCS were summarized. Results In 7 cases with URCS, 5 cases of completely URCS were associated with right atrial isomerism syndrome and confirmed by postpartum autopsy, and 2 cases of partially URCS were only with persistent left superior vena cava and confirmed by postnatal echocardiography. The karyotype analysis of 2 cases of partially URCS on amniotic fluid was normal. Conclusions There are some characteristic signs in ultrasonic features of URCS. URCS can be diagnosed by prenatally ultrasonography. A long axial section of the coronary sinus is the most important view for prenatal ultrasonic diagnosis of URCS. Key words: Ultrasonography, prenatal; Fetus; Unroofed coronary sinus

Effect of Prenatal Laterality Disturbance and Its Accompanying Anomalies on Survival

In this retrospective, observational study of fetuses diagnosed with a laterality disturbance we describe the findings and outcome of fetuses diagnosed between 1980 and 2017 at a tertiary fetal-pediatric cardiology unit. In addition we sought to identify features which impact on outcome. Left atrial isomerism (LAI) was diagnosed in 177 babies and right atrial isomerism (RAI) in 100. Major structural heart disease was present in all cases of RAI and 91% with LAI. Complete heart block (CHB) was present in 40% of LAI. For surviving live-born infants a biventricular circulation was feasible in 3% with RAI and 43% with LAI. The median survival for live-borns with LAI was 13 months (range 0 to 272 months) and for RAI 19 months (range 0.3 to 292 months). The median postnatal survival with CHB was 0.2 months (range 0 to 228 months) compared to 44 months with sinus rhythm (interquartile range 0 to 272 months; p <0.0001). The 5-year survival was 1980 to 1989, RAI 0%, LAI 0%; 1990 to 1999, RAI 62%, LAI 54%; 2000 to 2009, RAI 59%, LAI 53%; 2010 to 2017, RAI 67%, LAI 75% by era. The rate of intrauterine death remained. Risk factors for death/transplantation for RAI were total anomalous pulmonary venous drainage, left heart obstruction (hazard ratios 2.7, p = 0.048; 5.8, p = 0.03) and for LAI: CHB, anomalous pulmonary venous drainage and right heart obstruction (hazard ratios 11.5, 6.2, 3.8, respectively (p = 0.008, p = 0.003, p <0.001)). In conclusion, laterality disturbances represent a complex form of congenital heart disease and although survival is improved, it remains poor especially in the presence of anomalous pulmonary venous drainage, stenotic and/or atretic valves, and CHB.

Primary Draining Vein Stenting for Obstructive Total Anomalous Pulmonary Venous Connection in Neonates with Right Atrial Isomerism and Functional Single Ventricle Improves Outcome.

For neonates with right atrial isomerism (RAI), functional single ventricle (f-SV), and obstructive total anomalous pulmonary venous connection (TAPVC), primary TAPVC repair (TAPVCR) has a poor outcome. At our hospital, the survival rate at 1year of such neonates undergoing primary TAPVCR between 1999 and 2010 (TAPVCR group) was 30% (3/10). Most deceased cases suffered from capillary leak syndrome and unstable pulmonary resistance after the surgeries. We sought to determine whether less invasive primary draining vein stenting (DVS) improved the outcome of these neonates. We investigated outcomes in consecutive nine such neonates (median gestational age 38 weeks, birth weight 2.8kg, females 4) who underwent primary DVS with 6-mm-diameter Palmaz® Genesis® stents at our hospital between 2007 and 2017 (DVS group). Eight patients underwent subsequent surgeries to adjust the pulmonary flow after decreased pulmonary resistance. The survival rate at 1year after the first interventions in the DVS group improved to 77% (7/9), although there was a difference between the interventional eras of the two groups. Of the seven patients who underwent multiple stent redilations with a larger balloon or additional stenting in other sites until the next stage of surgery at a median age of 8months, four received a bidirectional Glenn (BDG) shunt and TAPVCR and three underwent TAPVCR, with two of those cases reaching BDG. Less invasive primary DVS improved the outcome of neonates with RAI, f-SV, and obstructive TAPVC, with many reaching BDG. Patient selection to advance toward Fontan is thought to further improve the outcome.