Dextro-transposition Of The Great Arteries Research Articles

Prenatal sonography of the foramen ovale predicts urgent balloon atrial septostomy in neonates with complete transposition of the great arteries

Hypoxia caused by inadequate intracardiac mixing owing to a restrictive foramen ovale is a potentially life-threatening complication in neonates with dextro-transposition of the great arteries. An urgent balloon atrial septostomy is a procedure of choice in such cases, but dependent on the availability of a 24-hour interventional cardiology facility. The prenatal identification of predictors for an urgent balloon atrial septostomy at birth would help in optimizing the management of these neonates, minimizing the risk of hypoxic damage. This study aimed to predict with prenatal echocardiography the need of urgent balloon atrial septostomy in neonates with dextro-transposition of the great arteries. This was a retrospective cohort study of patients with a prenatal diagnosis of transposition of the great arteries that were delivered in our center between 2010 and 2019, for whom fetal ultrasound echocardiograms obtained at less than 3 weeks before delivery were available. The following parameters were systematically obtained at fetal echocardiography: size and appearance of the foramen ovale, septum primum excursion (foramen ovale flap angle at the maximal excursion), diameters of the atria, and size of the ductus arteriosus. Balloon atrial septostomy was defined as urgent if performed within 12 hours from birth in neonates with restrictive foramen ovale. Neonatal follow-up was obtained through medical records analysis. From November 2007 to April 2019, 160 fetuses with complete transposition of the great arteries were referred to our echocardiography laboratory and 60 of these were included in the analysis; 27 underwent urgent balloon atrial septostomy, 11 elective balloon atrial septostomy, and 22 no balloon atrial septostomy. The size of the foramen ovale was the best predictor of an urgent balloon atrial septostomy. A measurement of >6.5 mm had a sensitivity of 100% and a false positive rate of 45%. Fetal echocardiography predicts the need of an urgent balloon atrial septostomy in fetuses with dextro-transposition of the great arteries although with a limited precision. In our experience, a measurement of the foramen ovale within 3 weeks of delivery had the greatest accuracy.

Modified pulmonary artery banding: A novel strategy for balancing pulmonary blood flow with transposed great arteries.

ObjectiveTo study the outcomes of a novel modified pulmonary artery banding (mPAB) technique used for staged repair of a subset of patients with complex transposition physiology.MethodsA total of 13 patients who underwent mPAB during their staged repair (biventricular repair [BVR], n = 6) or palliation (1-1/2 repair, n = 1; univentricular repair [UVR], n = 6) from 2004 to 2020 were studied retrospectively. A restrictive interposition graft was used to reconstruct the main PA between the pulmonary root and the distal pulmonary confluence, functioning as a mPAB. Twelve of the 13 patients (92.3%) underwent a concurrent arterial switch operation (ASO), of which 6 were palliative ASOs for 1-1/2 repair (n = 1) or UVR (n = 5). Patient weight and cardiac anatomy determined the size of interposition graft.ResultsThe disease spectrum included dextro transposition of the great arteries (d-TGA) with multiple ventricular septal defects (VSDs) (n = 4), Taussig–Bing anomaly (n = 3), d-TGA with VSD and hypoplastic right ventricle (RV) (n = 3), double-inlet left ventricle with l-TGA (n = 2), and congenitally corrected TGA with double-outlet RV (n = 1). The Lecompte procedure was performed in 10 patients. Predischarge echocardiography revealed a band gradient of 61 mm Hg (interquartile range [IQR], 40-90 mm Hg) for BVR/1-1/2 ventricular repair (n = 7) and 49 mm Hg (IQR, 37-61 mm Hg) for UVR (n = 6). Survival was 100% at a median follow-up of 3.7 years (IQR, 2.6-4.0 years).ConclusionsThe mPAB technique is effective and reproducible for staged BVR or UVR for patients with TGA. It effectively regulates pulmonary blood flow, may reduce neopulmonary root distortion, and eliminates complications associated with band migration in standard PAB.

Reliability of Fetal Echocardiography in Predicting Postnatal Critical Hypoxia in Patients with Transposition of Great Arteries and Intact Ventricular Septum.

Critical hypoxemia soon after birth is the most critical preoperative determinant of neurological outcomes and survival in newborns with Dextro Transposition of the Great Arteries and Intact Ventricular Septum (D-TGAIVS). Our study aimed to define fetal echocardiographic aspects that can better predict neonates with D-TGAIVS at risk for restricted interatrial communication after birth. 31 fetuses with a prenatal diagnosis of D-TGAIVS were included in our study. We divided patients with D-TGAIVS according to the timing of balloon atrial septostomy: Urgent, Not-Urgent and no BAS. We identified five fetal echocardiographic aspects of the interatrial septum (redundant, aneurysmal, flat, fixed, hypermobile). No significant differences in these fetal echocardiographic features were found between the three different groups of D-TGAIVS according to the timing of balloon atrial septostmy. However, only two patients showed flat appearance of interatrial communication: both needed Urgent balloon atrial septostomy. The prevalence of hypermobile septum primum was significantly lower in the control group compared to patients with D-TGAIVS. Fetal echocardiographic aspects cannot predict patients with D-TGAIVS who will not need Urgent balloon atrial septostomy. Therefore, we recommended a delivery in a tertiary center, equipped for Urgent balloon atrial septostomy, for all patients with D-TGAIVS regardless of fetal echocardiographic features.

Profile of congenital heart disease and access to definitive care among children seen at Gulu Regional Referral Hospital in Northern Uganda: a four-year experience

ObjectivesThe aim of this study was to describe the profile of Congenital Heart Disease [CHD] and access to definitive surgical or catheter-based care among children attending a regional referral hospital in Northern Uganda.MethodsThis was a retrospective chart review of all children aged less than 17 years attending Gulu Regional Referral Hospital Cardiac clinic from November 2013 to July 2017.ResultsA total of 295 children were diagnosed with CHD during the study period. The median age at initial diagnosis was 12 months [IQR: 4–48]. Females comprised 59.3% [n = 175] of cases. Diagnosis in the neonatal period accounted for only 7.5 % [n = 22] of cases. The commonest CHD seen was ventricular septal defect [VSD] in 19.7 % [n = 58] of cases, followed by atrioventricular septal defect (AVSD) in 17.3 % [n = 51] and patent ductus arteriosus (PDA) in 15.9 % [n = 47]. The commonest cyanotic CHD seen was tetralogy of Fallot [TOF] in 5.1 % [n = 15], followed by double outlet right ventricle [DORV] in 4.1 % [n = 12] and truncus arteriosus in 3.4% [n = 10]. Dextro-transposition of the great arteries [D-TGA] was seen in 1.3 % [n = 4]. At initial evaluation, 76 % [n = 224] of all CHD cases needed definitive intervention and 14 % of these children [n = 32] had accessed surgical or catheter-based therapy within 2 years of diagnosis. Three quarters of the cases who had intervention [n = 24] had definitive care at the Uganda Heart Institute (UHI), including all 12 cases who underwent catheter-based interventions. No mortalities were reported in the immediate post-operative period and in the first annual follow up in all cases who had intervention.ConclusionsThere is delayed diagnosis of most rural Ugandan Children with CHD and access to definitive care is severely limited. The commonest CHD seen was VSD followed by AVSD. The majority of patients who had definitive surgery or transcatheter intervention received care in Uganda.

Prenatal diagnosis, associated findings and postnatal outcome of fetuses with truncus arteriosus communis (TAC)

PurposeTo assess the spectrum of associated anomalies, the intrauterine course, postnatal outcome and management of fetuses with truncus arteriosus communis (TAC)MethodsAll cases of TAC diagnosed prenatally over a period of 8 years were retrospectively collected in two tertiary referral centers. All additional prenatal findings were assessed and correlated with the outcome. The accuracy of prenatal diagnosis was assessed.ResultsThirty nine cases of TAC were diagnosed prenatally. Mean gestational age at first diagnosis was 22 weeks (range 13–38). Two cases were lost follow-up. Correct prenatal diagnosis of TAC was made in 87.5% and of TAC subtype in 90.5%. Prenatal diagnosis was incorrect in three cases: one newborn had aortic atresia with ventricular septal defect (VSD) postnatally, one had hypo-plastic right ventricle with dextro transposition of the great arteries (d-TGA) with coarctation of the aorta and a third newborn had tetralogy of fallot (TOF) with abnormal origin of the left pulmonary artery arising from the ascending aorta postnatally. These 3 cases were excluded from further analysis.In 26.5% of cases, TAC was an isolated finding. 38.2% of fetuses had additional chromosomal anomalies. Among them, microdeletion 22q11.2 was most common with a prevalence of 17.6% in our cohort. Another 3 fetuses were highly suspicious for non-chromosomal genetic syndromes due to their additional extra-cardiac anomalies, but molecular diagnosis could not be provided. Major cardiac and extra-cardiac anomalies occurred in between 8.8% and 58.8%, respectively. Predominantly, extra-cardiac anomalies occurred in association with chromosomal anomalies. Additionally, severe IUGR occurred in 17.6%.There were 14 terminations of pregnancy (41.2%), 1 (2.9%) intrauterine fetal death, 5 postnatal deaths (14.7%) and 14 (41.2%) infants were alive at last follow-up. Intention-to-treat survival rate was 70%. Mean follow-up among survivors was 42 months (range 6–104). Postoperative health status among survivors was excellent in 78.6%, but 46.2% needed repeated re-interventions due to recurrent pulmonary artery or conduit stenosis. The other 21.4% of survivors were significantly impaired due to non-cardiac problems.ConclusionTruncus arteriosus communis is a rare and complex cardiac anomaly that can be diagnosed prenatally with high precision. TAC is frequently associated with chromosomal and extra-cardiac anomalies, leading to a high intrauterine and postnatal loss rate due to terminations and perioperative mortality. Without severe extra-cardiac anomalies, postoperative health status is excellent, independent of the subtype of TAC, but the prevalence of repeated interventions due to recurrent stenosis is high.

Implantable cardioverter defibrillators in adult congenital heart disease: long-term follow up of therapies, complications and clinical events

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Adults with congenital heart disease (ACHD) at increased risk for sudden cardiac death (SCD) often undergo implantable cardioverter defibrillator (ICD) implantation at young ages. Data evaluating the long-term outcomes of ICD in this population remain scarce. We aimed to characterize the population with ACHD and an ICD. Methods Consecutive ACHD submitted to an ICD implantation in a single tertiary center were evaluated. Data on baseline clinical features, heart defect, indication for ICD, type of device, ICD-related complication and therapies and mortality during follow-up were collected. Results A total of 34 patients (P) were evaluated. Median age at implant was 39.3 years (interquartile range [IQR] 29-5-53.6) and median left ventricular ejection fraction (LVEF) was 43.5% (IQR 28.0-53.3). The most common heart defect was tetralogy of Fallot (11P;32,3%), followed by dextro-transposition of the great arteries, ostium secundum atrial septal defect (ASD) and ventricular septal defect (Figure 1). All P were submitted to surgical correction (median age at surgery 12.5 years [IQR 3.0-29.1]). Sixteen P underwent ICD implantation for primary prevention of SCD, owing to complex cardiopathy and ventricular dysfunction, and 18P due to spontaneous ventricular tachyarrhythmias. The implantable devices were a single-chamber ICD in 55.9%, a double-chamber ICD in 17.6%, a subcutaneous ICD in 20.6% and a CRT-D in 5.9%. During a median follow-up of 4.5 years (IQR 2.1-8.8), 52.9% of the P received appropriate ICD therapies, corresponding to 37.5% and 66.7% of primary and secondary prevention P, respectively. Median time to first arrhythmic event was 25.3 months (IQR 13.7-52.9). Six P (17.6%) suffered ICD-related complications and 20.6% received inappropriate therapies due to supraventricular tachyarrhythmias. During follow-up, 8.8% were submitted to heart transplant and 29.4% died (Table 1). ICD therapies were associated with a composite of death, cardiac transplantation and hospital admission (OR 5.0, 95% CI 1.0-24.3). Conclusion ACHD with ICD experience high rate of appropriate therapies, including those implanted for primary prevention. The long-term burden of ICD-related complications and inappropriate shocks underlines the need for careful risk stratification and close monitoring. The increased survival of this population justifies collecting data on long-term outcomes to improve its care. Abstract Figure.

Fetal cerebrovascular response to maternal hyperoxygenation in congenital heart disease: effect of cardiac physiology.

Fetal cerebrovascular resistance is influenced by several factors in the setting of intact autoregulation to allow for normal cerebral blood flow and oxygenation. Maternal hyperoxygenation (MH) allows for acute alterations in fetal physiology and can be a tool to test cerebrovascular reactivity in late-gestation fetuses. In this study, we utilized MH to evaluate cerebrovascular reactivity in fetuses with specific congenital heart disease (CHD). This was a cross-sectional study of fetuses with complex CHD compared to controls without CHD. CHD cases were grouped according to physiology into: left-sided obstructive lesion (LSOL), right-sided obstructive lesion (RSOL) or dextro-transposition of the great arteries (d-TGA). Subjects underwent MH testing during the third-trimester fetal echocardiogram. The pulsatility index (PI) was calculated for the fetal middle cerebral artery (MCA), umbilical artery (UA) and branch pulmonary artery (PA). The change in PI from baseline to during MH was compared between each CHD group and controls. Sixty pregnant women were enrolled (CHD, n = 43; control, n = 17). In the CHD group, there were 27 fetuses with LSOL, seven with RSOL and nine with d-TGA. Mean gestational age was 33.9 (95% CI, 33.6-34.2) weeks. At baseline, MCA-PI Z-score was lowest in the LSOL group (-1.8 (95% CI, -2.4 to -1.2)) compared with the control group (-0.8 (95% CI, -1.3 to -0.3)) (P = 0.01). In response to MH, MCA-PI Z-score increased significantly in the control and d-TGA groups but did not change significantly in the LSOL and RSOL groups. The change in MCA-PI Z-score was significantly higher in the control group than in the LSOL group (0.9 (95% CI, 0.42-1.4) vs 0.12 (95% CI, -0.21 to 0.45); P = 0.03). This difference was more pronounced in the LSOL subgroup with retrograde aortic arch flow. Branch PA-PI decreased significantly in response to MH in all groups, with no difference in the change from baseline to MH between the groups, while UA-PI was unchanged during MH compared with at baseline. The fetal cerebrovascular response to MH varies based on the underlying CHD diagnosis, suggesting that cardiovascular physiology may influence the autoregulatory capacity of the fetal brain. Further studies are needed to determine the clinical implications of these findings on long-term neurodevelopment in these at-risk children. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Metabolic syndrome and coronary artery disease in adults with congenital heart disease.

In adults with congenital heart disease (ACHD), conditions acquired with aging, such as metabolic syndrome, hypertension, diabetes mellitus, and obesity, can negatively influence the original cardiovascular disease. Metabolic syndrome has a higher prevalence in ACHD than in the general population. In contrast, coronary artery disease shows a similar prevalence in adults with acyanotic CHD and the general population, while adults with cyanotic CHD, even after repair, have an even lower incidence of coronary artery disease than the general population/adults with acyanotic CHD. However, even in those with cyanotic CHD, coronary artery disease can develop when they have risk factors such as obesity, dyslipidemia, hypertension, diabetes mellitus, smoking habit, or limited exercise. The prevalence of risk factors for cardiovascular disease is similar between ACHD and the general population, but an increased risk of coronary atherosclerosis has been observed for congenital coronary artery anomalies, dextro-transposition of the great arteries after arterial switch operation, Ross procedure, and coarctation of the aorta. Aortopathy may be an additional risk factor for cardiovascular disease. As ACHD have other abnormalities that may make the heart more vulnerable to both the development of atherosclerosis and adverse cardiovascular sequelae, regular evaluation of their cardiovascular disease risk status is recommended. Metabolic syndrome is more common among ACHD than in the general population, and may therefore increase the future incidence of atherosclerotic coronary artery disease even in ACHD. Thus, ACHD should be screened for metabolic syndrome to eliminate risk factors for atherosclerotic coronary artery disease.

Successful Management of a COVID-19 Positive Infant With Transposition of the Great Arteries.

A six-week-old infant presented in extremis and was diagnosed with dextro-transposition of the great arteries, intact ventricular septum, features of left ventricular deconditioning, and abnormal coronary arteries. Treatment with prostaglandin E1 and balloon atrial septostomy was insufficient, necessitating extracorporeal membrane oxygenation (ECMO). Severe acute respiratory syndrome coronavirus-2 was detected. The arterial switch operation was delayed by eight days because of COVID-19. Although stable on ECMO, the infant was treated with remdesivir. Extracorporeal membrane oxygenation was not required postoperatively with chest closure on day 2 and extubation on day 5.

Lymphocyte Immune Response and T Cell Differentiation in Fontan Patients with protein-losing enteropathy.

Background Protein-losing enteropathy (PLE) is a severe complication of the Fontan circulation. There is increasing discussion about whether lymphatic dysregulation is involved as pathomechanism of PLE. This investigation focuses on the interplay between alteration of lymphatic cells and immunologic pathway alterations. Methods Micro-ribonucleic acid (miRNA) expression profiling was performed in 49 patients ( n = 10 Fontan patients with PLE, n = 30 Fontan patients without PLE, and n = 9 patients with dextro-transposition of the great arteries (dTGA). miRNA pathway analysis was performed to identify significantly enriched pathways. To determine lymphocyte populations and subtypes multiparameter flow cytometry was used. Results miRNAs pathway analysis of Fontan patients with PLE revealed 20 significantly changed networks of which four of the ten largest were associated with immunologic processes. This finding is supported by significant T cell deficiency with decreased CD4+ count ( p = 0.0002), altered CD4 +/CD8+ ratio, and significantly modified CD4+ ( p < 0.0001) and CD8+ ( p = 0.0002) T cell differentiation toward effector and terminal differentiated T cells in Fontan patients with PLE. Analyses of CD4+ T cell subsets demonstrated significantly increased frequencies of CD4+ CD25+ CD127– regulatory T cells (Treg) in Fontan patients with PLE ( p = 0.0011). Conclusion PLE in Fontan patients is associated with severe lymphopenia, T cell deficiency, significant alterations of T cell differentiation, and increased Treg frequency reflecting an immune status of chronic inflammation and shortened protection against pathogens and autoimmunity. These cellular alterations seemed to be dysregulated by several miRNA controlled immunological pathways.

Preoperative Anemia and Outcomes After Corrective Surgery in Neonates With Dextro-Transposition of the Great Arteries

The authors aimed to assess whether untreated preoperative anemia was associated with increased risk for adverse outcomes after the arterial switch operation in neonates with dextro-transposition of the great arteries (d-TGA). Retrospective cohort study. Single cardiac surgery center. Eighty-two newborns with d-TGA. The authors categorized the cohort into the following two groups: the infants with preoperative anemia group (defined as a hematocrit <0.40 L/L) and the control group. Preoperative anemia was diagnosed in 21 (25.6%) infants. Anemic infants received intraoperative red blood cell transfusions significantly more often than controls (81.0% v 34.4%, p < 0.001). No differences were observed in the incidence of adverse events, duration of hospitalization (median 27 days v 26 days, p = 0.881), and mortality (0% v 4.9%, p = 0.566). Postnatal hematocrit was the only variable independently associated with preoperative anemia in multivariate logistic regression analysis (unit odds ratio, 0.832; 95% confidence interval, 0.743-0.931; p = 0.001). Untreated preoperative anemia was not associated with adverse outcomes in neonates undergoing reparative surgery for d-TGA.

Gene-environment interactions between air pollution and biotransformation enzymes and risk of birth defects.

Genetic and environmental factors have been observed to influence risks for birth defects, though few studies have investigated gene-environment interactions. Our aim was to examine the interaction terms of gene variants in biotransformation enzyme pathways and air pollution exposures in relation to risk of several structural birth defects. We evaluated the role of ambient air pollutant exposure (nitrogen dioxide [NO2 ], nitrogen oxide, carbon monoxide, particulate matter <10 [PM10 ] and <2.5 [PM2.5 ] microns) during pregnancy and 104 gene variants of biotransformation enzymes from infant bloodspots or buccal cells in a California population-based case-control study in 1997-2006. Cases included cleft lip with or without cleft palate (N = 206), gastroschisis (N = 94), tetralogy of Fallot (N = 69), and dextro-transposition of the great arteries (d-TGA; N = 40) and were compared to 208 nonmalformed controls. Overall, the results were not consistent, though did highlight some associations for further investigation as indicated by Wald chi-square test p value <.1. Increased risk of cleft lip was associated with exposure to high PM10 and two CYP gene variants. High PM2.5 and the variant of SLCO1B1 was associated with increased risk of teratology of Fallot. Higher NO2 and two gene variants, CYP2A6 and SLC01B1, were associated with increased risk of d-TGA. Results for gastroschisis were inconsistent in direction and across pollutants. These exploratory results suggest that some individuals based on their genetic background may be more susceptible to the adverse effects of air pollution.

Monthly variation in univentricular heart and transposition of the great arteries – 10–year national population-based cohort study

ObjectiveMonthly variation in the total prevalence of the univentricular heart (UVH) and dextro-transposition of the great arteries (d-TGA) at gestational age 7 + 0 weeks was assessed to determine potential environmental factors, such as viral or bacterial infections, underlying the variation. Study designThe nationwide retrospective ten-year population-based cohort consisted of 592 733 births and 2764 terminated pregnancies due to fetal anomaly. The pre- or postnatally diagnosed cases of UVH (n = 440) and simple d-TGA (n = 127) from five national registers included live births, stillbirths, and pregnancy terminations due to fetal anomaly. We evaluated the variation in the monthly total prevalence of UVH and d-TGA at gestational age 7 + 0 weeks. The monthly variation of UVH and d-TGA was also compared with monthly variation in reported viral and bacterial infections. ResultsIn the UVH and d-TGA, we observed significant monthly variation in total prevalence. However, we observed no correlations in the studied viral or bacterial infections and the number of cases. ConclusionsAssessing monthly variation in total prevalence at early pregnancy, including pregnancy terminations and stillbirths, and using first-trimester timing provides the most accurate information on the variation. The reasons for monthly variation remain unclear, but we observed no associations with specific viral or bacterial infections.

Multimodality Imaging of Transposition of the Great Arteries.

Transposition of the great arteries (TGA) is a congenital conotruncal abnormality characterized by discordant connections between the ventricles and great arteries, with the aorta originating from the right ventricle (RV), and the pulmonary artery (PA) originating from the left ventricle (LV). The two main types of TGA are complete transposition or dextro-transposition of the great arteries (D-TGA), commonly referred to as d-loop, and congenitally corrected transposition (CCTGA), commonly referred to as l-loop or L-TGA. In D-TGA, the connections between the ventricles and atria are concordant, whereas in CCTGA they are discordant, with the left atrium connected to the RV, and the right atrium connected to the LV. D-TGA manifests during the neonatal period and can be surgically managed by atrial switch operation (AtrSO), arterial switch operation (ASO), Rastelli procedure, or Nikaidoh procedure. Arrhythmia, systemic ventricular dysfunction, baffle stenosis, and baffle leak are the common complications of AtrSO, whereas supravalvular pulmonary or branch PA stenosis, neoaortic dilatation, and coronary artery narrowing are the common complications of ASO. CCTGA may manifest late in life, even in adulthood. Surgeries for associated lesions such as tricuspid regurgitation, subpulmonic stenosis, and ventricular septal defect may be performed. A double-switch operation that includes both the atrial and arterial switch operations constitutes anatomic correction for CCTGA. Imaging plays an important role in the evaluation of TGA, both before and after surgery, for helping define the anatomy, quantify hemodynamics, and evaluate complications. Transthoracic echocardiography is the first-line imaging modality for presurgical planning in children with TGA. MRI provides comprehensive morphologic and functional information, particularly in adults after surgery. CT is performed when MRI is contraindicated or expected to generate artifacts. The authors review the imaging appearances of TGA, with a focus on pre- and postsurgical imaging. Online supplemental material is available for this article. ©RSNA, 2021.

Performance on the ROCF at 8 Years Predicts Academic Achievement at 16 Years in Individuals with Dextro-Transposition of the Great Arteries.

This study examined longitudinal associations between performance on the Rey-Osterrieth Complex Figure-Developmental Scoring System (ROCF-DSS) at 8 years of age and academic outcomes at 16 years of age in 133 children with dextro-transposition of the great arteries (d-TGA). The ROCF-DSS was administered at the age of 8 and the Wechsler Individual Achievement Test, First and Second Edition (WIAT/WIAT-II) at the ages of 8 and 16, respectively. ROCF-DSS protocols were classified by Organization (Organized/Disorganized) and Style (Part-oriented/Holistic). Two-way univariate (ROCF-DSS Organization × Style) ANCOVAs were computed with 16-year academic outcomes as the dependent variables and socioeconomic status (SES) as the covariate. The Organization × Style interaction was not statistically significant. However, ROCF-DSS Organization at 8 years was significantly associated with Reading, Math, Associative, and Assembled academic skills at 16 years, with better organization predicting better academic performance. Performance on the ROCF-DSS, a complex visual-spatial problem-solving task, in children with d-TGA can forecast academic performance in both reading and mathematics nearly a decade later. These findings may have implications for identifying risk in children with other medical and neurodevelopmental disorders affecting brain development.

Prenatal Delineation of Coronary Anatomy in Dextro-Transposition of Great Arteries.

Background:Dextro-transposition of the great arteries (D-TGA) is the second-most common cyanotic congenital heart disease with variable coronary artery anatomy. The arterial switch procedure has revolutionized outcomes for this defect, with coronary anatomy being a key determinant of both short- and long-term outcomes following surgical repair. The assessment of coronary anatomy is usually undertaken in the postnatal period by transthoracic echocardiography, with assessment prenatally not being well studied. We sought to assess the feasibility of delineating the coronary arteries on fetal echocardiograms in a small cohort of patients followed prenatally.Methods:This was a retrospective review of fetuses with D-TGA from 2008 to 2018. Patients with prenatal diagnosis of D-TGA were reviewed for the assessment of coronary artery anatomy. Details of coronary artery anatomy diagnosed prenatally were compared with postnatal transthoracic echocardiograms and intraoperative findings.Results:Thirty-four fetuses with findings of D-TGA on prenatal echocardiograms were reviewed. 14/34 fetuses had attempted delineation of coronary artery anatomy, with average gestational age of 28 weeks (range 23–31 weeks) at the time of diagnosis. Two-dimensional and color Doppler imaging of the coronary arteries on both short and long axis images were performed, with complete delineation being possible in ~ 86% of fetuses. These findings were confirmed postnatally.Conclusions:Fetuses with D-TGA can have variable coronary artery anatomy which drives postnatal outcomes. Our study describes a cohort of patients with D-TGA wherein coronary artery anatomy was assessed. We demonstrate that coronary artery evaluation is feasible prenatally with optimal imaging techniques, being more successful after 25 weeks' gestation. The potential knowledge of dangerous variants can help with referral to centers of excellence for appropriate postnatal management and facilitate prenatal care accordingly.

Hypothermia for cardiogenic encephalopathy in neonates with dextro-transposition of the great arteries.

Neonates with dextro-transposition of the great arteries (d-TGA) may experience rapid haemodynamic deterioration and profound hypoxaemia after birth. We report on d-TGA patients with severe acidosis, encephalopathy and their treatment with systemic hypothermia. This study is a single-centre retrospective cohort analysis of newborns with d-TGA. Ninety-five patients (gestational age ≥35 weeks) with d-TGA and intended arterial switch operation were included. Ten infants (10.5%) with umbilical arterial blood pH > 7.10 experienced profound acidosis (pH < 7.00) within the first 2 h of life. Six of these patients displayed signs of encephalopathy and received therapeutic hypothermia. Apgar scores at 5 min independently predicted the development of neonatal encephalopathy during postnatal transition (unit Odds Ratio 0.17, 95% confidence interval 0.06-0.49, P = 0.001). Infants treated with hypothermia had a more severe preoperative course and required more often mechanical ventilation (100% vs 35%, P = 0.003), treatment with inhaled nitric oxide (50% vs 2.4%, P = 0.002) and inotropic support (67% vs 3.5%, P < 0.001), as compared to non-acidotic controls. The median age at cardiac surgery was 12 (range 6-14) days in cooled infants and 8 (4-59) days in controls (P = 0.088). Postoperative morbidity and total duration of hospitalization were not increased in infants receiving preoperative hypothermia. Mortality in newborns with severe preoperative acidosis was zero. Newborn infants with d-TGA have a substantial risk for profound acidosis during the first hours of life. Systemic hypothermia for encephalopathic patients may delay corrective surgery without compromising perioperative outcomes.

Gene-environment interactions between air pollution and biotransformation enzymes and risk of birth defects

Background: Genetic factors and environmental factors have been observed to influence risks for birth defects. Few studies have investigated gene-environment interactions that could contribute to birth defects. Our aim was to examine the interaction between gene variants in biotransformation enzyme pathways and ambient air pollution exposures and risk of several structural birth defects.Methods: We evaluated the role of ambient air pollutant exposure [nitrogen dioxide (NO2), nitrogen oxide, carbon monoxide, particulate matter &lt;10 (PM10) and &lt;2.5 (PM2.5) microns] during pregnancy and 104 gene variants of biotransformation enzymes from infant bloodspots or buccal cells in a California population-based case-control (409 cases and 208 nonmalformed controls) study. Cases included cleft lip with or without cleft palate (N=206), gastroschisis (N=94), tetralogy of Fallot (N=69) and dextro-transposition of the great arteries (d-TGA; N=40). We considered race/ethnicity and folic acid vitamin use as potential effect modifiers and adjusted for smoking.Results: We observed increased risk of d-TGA associated with interactions between CYP2A6 and NO2 (OR=7.1), SLCO1B1 and NO2 (OR=4.0), NAT2 and PM10 (OR=3.5), SLCO1B1 and PM10 (OR=3.0), SLCO2B1 and PM10 (OR=4.4). We also observed gene-environment interactions for cleft lip with or without cleft palate (CYP2D6 and PM10; OR=2.8), gastroschisis (CYP2C9 and PM10; OR=4.2) and tetralogy of Fallot (NAT2 and PM2.5; OR=5.0). Conclusions: These analyses show interactions between air pollution exposure during early pregnancy and gene variants associated with metabolizing enzymes with regard to risk of d-TGA, though results were less consistent for other birth defects. These exploratory results suggest that some individuals based on their genetic background may be more susceptible to the adverse effects of air pollution.

Cardiac resynchronization therapy for the failing systemic right ventricle: A systematic review

Patients with a systemic right ventricle (SRV) are at high risk for development of heart failure early in life. An SRV is encountered in patients with congenitally corrected transposition of the great arteries (CCTGA) or dextro-transposition of the great arteries (DTGA) with previous atrial switch repair (Mustard or Senning procedure). Progressive heart failure is one of the leading cause of mortality in these patients. Therefore, cardiac resynchronization therapy (CRT) has gained increasing momentum for use in this challenging congenital heart disease (CHD) population. However, current guidelines differ in recommendations for CRT in patients with an SRV as evidence supporting CRT has thus far only been described in case reports and retrospectively in relatively small study populations. In fact, the European Society of Cardiology Guideline for the management of grown-up congenital heart disease consider CRT to be ‘experimental’ in this population. This systematic review critically summarizes current literature on CRT in SRV patients and provides future perspectives for further research in this challenging and growing CHD population.

Management of 760-g Extremely Premature Infant With Dextro-Transposition of the Great Arteries

Extremely low birth weight neonates with complex congenital heart disease have increased mortality risk. Multi-organ dysfunction, pulmonary disease, fluctuating pulmonary vascular resistance, and complex cardiovascular anatomy create a challenge for effective management. We present the case of a 760-g neonate with dextro-transposition of the great arteries, ventricular septal defect, patent ductus arteriosus, and single coronary artery with proximal intramural segment of the right coronary artery branch. We describe features of preoperative care, surgical intervention, and postoperative course that enabled this infant to survive.