Common Genetic Variants Contribute to Risk of Transposition of the Great Arteries.

RATIONALE: Dextro-transposition of the great arteries (D-TGA) is a severe congenital heart defect which affects approximately 1 in 4,000 live births. While there are several reports of D-TGA patients with rare variants in individual genes, the majority of D-TGA cases remain genetically elusive. Familial recurrence patterns and the observation that most cases with D-TGA are sporadic suggest a polygenic inheritance for the disorder, yet this remains unexplored. OBJECTIVE: We sought to study the role of common single nucleotide polymorphisms (SNPs) in risk for D-TGA. METHODS AND RESULTS: We conducted a genome-wide association study in an international set of 1,237 patients with D-TGA and identified a genome-wide significant susceptibility locus on chromosome 3p14.3, which was subsequently replicated in an independent case-control set (rs56219800, meta-analysis P=8.6x10-10, OR=0.69 per C allele). SNP-based heritability analysis showed that 25% of variance in susceptibility to D-TGA may be explained by common variants. A genome-wide polygenic risk score derived from the discovery set was significantly associated to D-TGA in the replication set (P=4x10-5). The genome-wide significant locus (3p14.3) co-localizes with a putative regulatory element that interacts with the promoter of WNT5A, which encodes the Wnt Family Member 5A protein known for its role in cardiac development in mice. We show that this element drives reporter gene activity in the developing heart of mice and zebrafish and is bound by the developmental transcription factor TBX20. We further demonstrate that TBX20 attenuates Wnt5a expression levels in the developing mouse heart. CONCLUSIONS: This work provides support for a polygenic architecture in D-TGA and identifies a susceptibility locus on chromosome 3p14.3 near WNT5A. Genomic and functional data support a causal role of WNT5A at the locus.

Exome-Based Case-Control Analysis Highlights the Pathogenic Role of Ciliary Genes in Transposition of the Great Arteries.

RATIONALE: Transposition of the great arteries (TGA) is one of the most severe types of congenital heart diseases. Understanding the clinical characteristics and pathogenesis of TGA is, therefore, urgently needed for patient management of this severe disease. However, the clinical characteristics and genetic cause underlying TGA remain largely unexplored. OBJECTIVE: We sought to systematically examine the clinical characteristics and genetic cause for isolated nonsyndromic TGA. METHODS AND RESULTS: We recruited 249 patients with TGA (66 family trios) and performed whole-exome sequencing. The incidence of patent ductus arteriosus in dextro-TGA (52.7%) and dextrocardia/mesocardia in congenitally corrected TGA (32.8%) were significantly higher than that in other subtypes. A high prevalence of bicuspid pulmonic valve (9.6%) was observed in patients with TGA. Similar results were observed in a replication group of TGA (n=132). Through a series of bioinformatics filtering steps, we obtained 82 candidate genes harboring potentially damaging de novo, loss of function, compound heterozygous, or X-linked recessive variants. Established congenital heart disease-causing genes, such as FOXH1, were found among the list of candidate genes. A total of 19 ciliary genes harboring rare potentially damaging variants were also found; for example, DYNC2LI1 with a de novo putatively damaging variant. The enrichment of ciliary genes supports the roles of cilia in the pathogenesis of TGA. In total, 33% of the TGA probands had >1 candidate gene hit by putatively deleterious variants, suggesting that a portion of the TGA cases were probably affected by oligogenic or polygenic inheritance. CONCLUSIONS: The findings of clinical characteristic analyses have important implications for TGA patient stratification. The results of genetic analyses highlight the pathogenic role of ciliary genes and a complex genetic architecture underlying TGA.

Perioperative Hemostatic Management of a Newborn With Hereditary Hemophilia A Undergoing Emergent Surgery for Dextro-Transposition of the Great Arteries.

Hemophilia A is an inherited bleeding disorder characterized by a lack of plasma clotting factor VIII (FVIII). In prophylaxis or during surgery, FVIII infusions are necessary to prevent bleeding. The authors describe the perioperative challenges and application of a multidisciplinary hemostatic management approach to a Caucasian male newborn, with antenatal diagnoses of moderate hemophilia A (2 IU/dL) and dextro-transposition of the great arteries requiring arterial switch surgery within the first month of life. Because both conditions are rare, only few reports in the literature are available describing perioperative management of hemophilia in neonates and children undergoing cardiac surgery. After baseline FVIII determination and normal standard coagulation studies, iterative intravenous pharmacist-prepared plasma-derived FVIII boluses were calculated (35 IU/kg) and administered intravenously every 6 hours for 24 hours, then switched to a continuous infusion and guided by daily chromogenic clotting FVIII activity assay for targeted values between 80 and 100 IU/dL. Successful cardiac surgery, using cardiopulmonary bypass, was performed with continuous infusion of FVIII at 5 IU/kg/h. Thirteen days after surgery, the FVIII antibody screening remained negative and continuous infusion was switched in favor of a daily intravenous bolus treatment to facilitate reconciliation to the center of origin. The authors' multidisciplinary strategy, established antenatally, allowed for successful care in this highly complex and rare situation.

Assessment of ventricular flow dynamics by 4D-flow MRI in patients following surgical repair of d-transposition of the great arteries.

OBJECTIVES: To use 4D-flow MRI to describe systemic and non-systemic ventricular flow organisation and energy loss in patients with repaired d-transposition of the great arteries (d-TGA) and normal subjects. METHODS: Pathline tracking of ventricular volumes was performed using 4D-flow MRI data from a 1.5-T GE Discovery MR450 scanner. D-TGA patients following arterial switch (n = 17, mean age 14 ± 5 years) and atrial switch (n = 15, 35 ± 6 years) procedures were examined and compared with subjects with normal cardiac anatomy and ventricular function (n = 12, 12 ± 3 years). Pathlines were classified by their passage through the ventricles as direct flow, retained inflow, delayed ejection flow, and residual volume and visually and quantitatively assessed. Additionally, viscous energy losses (ELv) were calculated. RESULTS: In normal subjects, the ventricular flow paths were well ordered following similar trajectories through the ventricles with very little mixing of flow components. The flow paths in all atrial and some arterial switch patients were more irregular with high mixing. Direct flow and delayed ejection flow were decreased in atrial switch patients' systemic ventricles with a corresponding increase in residual volume compared with normal subjects (p = 0.003 and p < 0.001 respectively) and arterial switch patients (p < 0.0001 and p < 0.001 respectively). In non-systemic ventricles, arterial switch patients had increased direct flow and decreased delayed ejection fractions compared to normal (p = 0.007 and p < 0.001 respectively) and atrial switch patients (p = 0.01 and p < 0.001 respectively). Regions of high levels of mixing of ventricular flow components showed elevated ELv. CONCLUSIONS: 4D-flow MRI pathline tracking reveals disordered ventricular flow patterns and associated ELv in d-TGA patients. KEY POINTS: • 4D-flow MRI can be used to assess intraventricular flow dynamics in d-TGA patients. • d-TGA arterial switch patients mostly show intraventricular flow dynamics representative of normal subjects, while atrial switch patients show increased flow disorder and different proportions of intraventricular flow volumes. • Flow disruption and disorder increase viscous energy losses.

Associations Between Age at Arterial Switch Operation, Brain Growth, and Development in Infants With Transposition of the Great Arteries.

BACKGROUND: Brain injury, impaired brain growth, and long-term neurodevelopmental problems are common in children with transposition of the great arteries. We sought to identify clinical risk factors for brain injury and poor brain growth in infants with transposition of the great arteries undergoing the arterial switch operation, and to examine their relationship with neurodevelopmental outcome. METHODS: The brains of 45 infants with transposition of the great arteries undergoing surgical repair were imaged pre- and postoperatively using magnetic resonance imaging. Brain weight z scores were calculated based on brain volume and autopsy reference data. Brain injury scores were determined as previously described. Neurodevelopment was assessed at 18 months using the Bayley-III scores of infant development. The relationships between clinical variables, brain injury, perioperative brain growth, and 18-month Bayley-III scores were analyzed. RESULTS: On preoperative imaging, moderate or severe white matter injury was present in 10 of 45 patients, whereas stroke was seen in 4 of 45. A similar prevalence of injury was seen on postoperative imaging, and we were unable to identify any clinical risk factors for brain injury. Brain weight z scores decreased perioperatively in 35 of 45 patients. The presence of a ventricular septal defect ( P=0.009) and older age at surgery ( P=0.007) were associated with impaired perioperative brain growth. When patients were divided into those undergoing surgery during the first 2 weeks of life (32/45) versus those being repaired later (13/45), infants repaired later had significantly worse perioperative brain growth (late repair postoperative brain weight z = -1.0±0.90 versus early repair z = -0.33±0.64; P=0.008). Bayley-III testing scores fell within the normal range for all patients, although age at repair ( P=0.03) and days of open chest ( P=0.03) were associated with a lower composite language score, and length of stay was associated with a lower composite cognitive score ( P=0.02). CONCLUSIONS: Surgery beyond 2 weeks of age is associated with impaired brain growth and slower language development in infants with transposition of the great arteries cared for at our center. Although the mechanisms underlying this association are still unclear, extended periods of cyanosis and pulmonary overcirculation may adversely impact brain growth and subsequent neurodevelopment.

Perinatal and perioperative factors associated with mortality and an increased need for hospital care in infants with transposition of the great arteries: A nationwide 11-year population-based cohort.

INTRODUCTION: Newborn infants with transposition of the great arteries (d-TGA) need immediate care for an optimal outcome. This study comprised a nationwide 11-year population-based cohort of d-TGA infants, and assessed whether the implementation of a nationwide systematic fetal screening program, or other perinatal, or perioperative factors, are associated with mortality or an increased need for hospital care. MATERIAL AND METHODS: The national cohort consisted of all live-born infants with simple d-TGA (TGA ± small ventricular septal defect, n = 127) born in Finland during 2004-2014. Data were collected from six national registries. Prenatal diagnosis and perinatal and perioperative factors associated with mortality and length of hospitalization were evaluated. RESULTS: Preoperative mortality was 7.9%, and the total mortality was 8.7%. The prenatal detection rate increased after introducing systematic fetal anomaly screening from 5.0% to 37.7% during the study period (P < .0001), but the total mortality rate remained unchanged. All prenatally diagnosed infants (n = 27) survived. Lower gestational age (odds ratio 0.68, P = .012) and higher maternal age at birth (odds ratio 1.16, P = .036) were associated with increased mortality in multivariable analysis. Older infant age at time of operation (P = .002), longer aortic clamp time (P < .001), and higher maternal body mass index (P = .027) were associated with longer initial hospital stay. An extended need for hospital care during the first year of life was multi-factorial. CONCLUSIONS: In our cohort, none of the prenatally diagnosed d-TGA infants died. As a result of the limited prenatal detection rates, however, the sample size was insufficient to reach statistical significance. The d-TGA infants born with lower gestational age and to older mothers had increased mortality.

[Integrated management and prognosis analysis of fetus with complete transposition of the great arteries during pregnancy and perinatal period].

Objective: To investigate the prenatal diagnosis, integrated management and prognosis of fetal complete transposition of the great arteries (D-TGA) detected by ultrasonography. Methods: The prenatal diagnosis, integrated management and prognosis of 19 D-TGA fetuses found by ultrasound during pregnancy in Peking University People's Hospital from January 2014 to June 2019 were analyzed retrospectively. Results: The incidence of D-TGA was 0.12% (19/16 028) among fetuses diagnosed by ultrasound during 5 years. Among the 19 cases, there were 7 cases (7/19) of D-TGA alone, 7 cases (7/19) of D-TGA combined with ventricular septal defect (VSD), 5 cases (5/19) of D-TGA combined with other cardiac malformations; 2 cases (2/19) of D-TGA combined with extra cardiac malformations, and 1 case (1/19) of fetal growth restriction. Nuchal translucency (NT) thickening was found in 3 cases (3/19) at the first trimester of pregnancy. Among the 19 D-TGA fetuses found by ultrasound examination, 18 (18/19) had chromosome karyotype analysis of fetuses or newborns, and chromosomal abnormalities were found in 2 cases, all of which were terminated in the second trimester of pregnancy. The integrated management and multidisciplinary diagnosis and treatment of D-TGA fetuses during pregnancy and perinatal period were carried out. Nine cases (9/19) had induction in the second trimester of pregnancy, 10 cases (10/19) were delivered at term, and the gestational week of delivery was (38.3±0.7) weeks, among which 6 cases (6/10) were delivered by caesarean section due to obstetric factors, and 4 cases (4/10) were delivered by vaginal birth. The oxygen saturation was (69.2±11.3)% at birth and (77.8±6.7)% when transferred to the department of pediatrics. Except for one case lost to follow-up, the other 9 newborns received operation. The average operation time was (21.8±22.1) days after birth, 8 cases (8/9) completed one operation and 1 case (1/9) performed two operations. All of the 9 cases treated by surgery were followed up well. Conclusions: Prenatal diagnosis, individualized evaluation and integrated management during pregnancy and perinatal period should be carried out for the patients with fetal D-TGA detected by ultrasound. Fetal D-TGA is not an indication of cesarean section. The open of ductus arteriosus can be maintained with drugs when necessary after birth, and a good prognosis could be obtained through surgery.

Longitudinal Associations between Neurodevelopment and Psychosocial Health Status in Patients with Repaired D-Transposition of the Great Arteries.

OBJECTIVE: To examine associations between measurements of neurodevelopment and psychosocial health status at age 8 and 16 years in patients with repaired dextro-transposition of the great arteries. STUDY DESIGN: In the 16-year follow-up of the Boston Circulatory Arrest Study, 137 parents completed the Child Health Questionnaire-Parent Form-50, of whom 135 had completed the Child Health Questionnaire-Parent Form-50 when their child was age 8 years. Psychosocial and physical summary scores were used to assess change in health status from age 8 to 16 years. A comprehensive battery of neurodevelopmental testing was performed at ages 8 and 16 years to examine associations with adolescent health status. RESULTS: Lower psychosocial summary scores of 16 year old subjects with dextro-transposition of the great arteries were highly associated with numerous concurrent domains of neurodevelopmental function, most notably with higher (worse) scores on the Conners' Attention Deficit Hyperactivity Disorder/Diagnostic and Statistical Manual-4th Edition Scales (parent: r = -0.62, P < .001; adolescent: r = -0.43, P < .001) and the Behavior Rating Inventory of Executive Function Global Executive Composite (parent: r = -0.66, P < .001; adolescent: r = -0.39, P < .001). Psychosocial and physical summary scores tracked from ages 8 to 16 years (r = 0.44 and 0.47, respectively, P < .001 for each). Higher (worse) scores of multiple attention measures at age 8 years predicted worse psychosocial summary scores at age 16 years. CONCLUSIONS: Attention deficits at age 8 years were highly predictive of worse psychosocial health status in adolescence. Further studies are needed to assess whether treatment of childhood attention deficit hyperactivity disorder could improve adolescent well-being.

Coronary artery spasm in a neonate with transposition of great arteries: a rare complication and reason for heart transplant.

Arterial switch operation has become the standard of care for d-transposition of great arteries and has excellent short- and long-term outcomes. We report the case of a newborn with a diagnosis of d-transposition of great arteries with intact ventricular septum and a low-risk coronary artery anatomy who developed coronary artery vasospasm while coming off bypass following arterial switch operation in the operating room. The coronary artery spasm led to severe biventricular dysfunction and need for extracorporeal membranous oxygenation support. Despite extracorporeal membranous oxygenation and inotropic support, there was no improvement in the left ventricular function, and cardiac transplantation was performed after 8 days. The explanted heart showed extensive infarction of both ventricles. Both the coronary ostei were patent with no evidence of thrombus, suggesting coronary artery vasospasm rather than embolus or thrombus formation. This is the first case of coronary artery vasospasm in a neonate with d-transposition of great arteries leading to cardiac transplantation. We speculate that early identification of patients who are at a high risk for coronary vasospasm and prophylactic or timely infusion of papaverine directly into the coronary arteries may be beneficial in this condition.

Differences in clinical outcomes and cost between complex and simple arterial switches.

BACKGROUND: This study evaluates the morbidity, mortality, and cost differences between patients who underwent either a simple or a complex arterial switch operation. METHODS: A retrospective study of patients undergoing an arterial switch operation at a single institution was performed. Simple cases were defined as patients with d-transposition of the great arteries with usual coronary anatomy or circumflex artery originating from the right with either intact ventricular septum or ventricular septal defect. Complex cases included all other forms of coronary anatomy, aortic coarctation or arch hypoplasia, and Taussig-Bing anomalies. Costs were acquired using an institutional activity-based accounting system. RESULTS: A total of 98 patients were identified, 68 patients in the simple group and 30 in the complex group. The mortality rate was 2% for the simple and 7% for the complex group, p=0.23. Major morbidities including cardiac arrest, extracorporeal membrane oxygenation, a major coronary event, surgical or catheter-based re-intervention, stroke, or permanent pacemaker placement, non-cardiac surgical procedures, mediastinitis, and sepsis did not differ between the simple and complex groups (16 versus 27%, p=0.16). The complex group had increased bleeding requiring re-exploration (0 versus 10%, p=0.04). Hospital and ICU length of stay did not differ. Complex patients had higher overall hospital costs (simple $80,749 versus complex $97,387, p=0.01) and higher postoperative costs (simple $60,192 versus complex $70,132, p=0.02). The operating room and supplies accounted for the majority of the cost difference. CONCLUSION: Complex arterial switches can be safely performed with low rates of morbidity and mortality but at an increased cost.

Unusual association between corrected transposition of great arteries and supracardiac total anomalous pulmonary venous connection: a rare combination never reported before.

We describe the case of a 52-day-old child who was diagnosed with a rare combination of corrected transposition of great vessels - hypoplastic right ventricle with supracardiac total anomalous pulmonary venous connection.

Prenatal Diagnosis of Dextrocardia with Complex Congenital Heart Disease Using Fetal Intelligent Navigation Echocardiography (FINE) and a Literature Review.

Fetal dextrocardia is a type of cardiac malposition where the major axis from base to apex points to the right side. This condition is usually associated with a wide spectrum of complex cardiac defects. As a result, dextrocardia is conceptually difficult to understand and diagnose on prenatal ultrasound. The advantage of four-dimensional sonography with spatiotemporal image correlation (STIC) is that this modality can facilitate fetal cardiac examination. A novel method known as fetal intelligent navigation echocardiography (FINE) allows automatic generation of nine standard fetal echocardiography views in normal hearts by applying intelligent navigation technology to STIC volume datasets. In fetuses with congenital heart disease, FINE is also able to demonstrate abnormal cardiac anatomy and relationships when there is normal cardiac axis and position. However, this technology has never been applied to cases of cardiac malposition. We report herein for the first time, a case of fetal dextrocardia and situs solitus with complex congenital heart disease in which the FINE method was invaluable in diagnosing multiple abnormalities and defining complex anatomic relationships. We also review the literature on prenatal sonographic diagnosis of dextrocardia (with an emphasis on situs solitus), as well as tricuspid atresia with its associated cardiac features.

The Nikaidoh procedure for complex transposition of the great arteries: short-term follow-up.

BACKGROUND: The surgical treatment for complex forms of d-transposition of the great arteries associated with ventricular septal defect and left ventricular outflow tract obstruction remains controversial. In this study, we describe the classical surgical options - namely, the Rastelli procedure and the "réparation à l'étage ventriculaire" - and present our experience with the modified Nikaidoh procedure with early and short-term follow-up results. METHODS: Between 2007 and 2014, four patients with d-transposition of the great arteries associated with ventricular septal defect and left ventricular outflow tract obstruction underwent surgical repair at our institution by means of a modified Nikaidoh procedure. RESULTS: With a mean follow-up of 4.5 years, survival was 100%, and none of the patients required re-intervention or mechanical circulatory support. There was no recurrence of left ventricular outflow tract obstruction and no aortic valve regurgitation classified as more than mild. Left ventricular function was preserved. CONCLUSIONS: Aortic translocation with the modified Nikaidoh procedure is a safe and effective surgical treatment for certain complex forms of transposition of the great arteries, particularly those associated with ventricular septal defect and left ventricular outflow tract obstruction. It is associated with less need for re-intervention and better morbidity and mortality results in the short- and mid-term follow-up, when compared with the classical alternatives such as the Rastelli procedure.

Prenatal Echocardiographic Assessment of Foramen Ovale Appearance in Fetuses with D-Transposition of the Great Arteries and Impact on Neonatal Outcome.

INTRODUCTION: Neonates with D-transposition of the great arteries (dTGA) may die at birth because of the inadequate intracardiac mixing due to a misdiagnosed restrictive foramen ovale. We reviewed our experience in echocardiographic assessment and perinatal management of fetuses with dTGA searching for new features that may predict the need for urgent balloon atrial septostomy (BAS) immediately after birth. PATIENTS AND METHODS: We included fetuses diagnosed with dTGA between January 2000 and December 2014. We assessed pre- and postnatal appearance of the foramen ovale, ductus arteriosus and pulmonary veins. Both the diagnostic findings at the time of last prenatal echocardiogram and those findings deriving from a retrospective reevaluation of stored videos were considered. BAS was defined as urgent if performed in neonates with restrictive foramen ovale and severe hypoxemia. RESULTS: We reviewed 40 fetuses with dTGA. 20/40 fetuses received urgent BAS at birth. Not only the restrictive but also the hypermobile and the redundant appearance of the foramen ovale was significantly associated with urgent BAS (p < 0.0001, p = 0.002 and p = 0.0001, respectively). CONCLUSIONS: Prenatal evaluation of the foramen ovale appearance in fetuses with dTGA is still challenging. Based on our experience, also the redundant foramen ovale appearance may need urgent BAS at birth.

Long-Term Outcome of Mustard/Senning Correction for Transposition of the Great Arteries in Sweden and Denmark.

BACKGROUND: The atrial switch operation, the Mustard or Senning operation, for the transposition of the great arteries (TGA) was introduced in the late 1950s and was the preferred surgery for TGA until the early 1990s. The Mustard and Senning operation involves extensive surgery in the atria and leaves the right ventricle as the systemic ventricle. The Mustard and Senning cohort is now well into adulthood and we begin to see the long-term outcome. METHODS AND RESULTS: All the 6 surgical centers that performed Mustard and Senning operations in Sweden and Denmark identified all operated TGA patients. Information about death was obtained in late 2007 and early 2008 from the Danish and Swedish Centralised Civil Register by using the patients' unique national Civil Registration Numbers. Four hundred sixty-eight patients undergoing the atrial switch operation were identified. Perioperative 30-day mortality was 20%, and 60% were alive after 30 years of follow-up. Perioperative mortality was significantly increased by the presence of a ventricular septal defect, left ventricular outflow obstruction, surgery early in the Mustard and Senning era. However, only pacemaker implantation is predictive of long-term outcome (hazard ratio, 1.90; 95% confidence interval, 1.05-3.46, P=0.04), once the TGA patient has survived the perioperative period. The risk of reoperation was correlated to the presence of associated defects and where the first Mustard/Senning operation was performed. CONCLUSIONS: The long-term survival of patients with Mustard and Senning correction for TGA appears to be primarily determined by factors in the right ventricle and tricuspid valve and not the timing of or the type of surgery in childhood. Cardiac function necessitating the implantation of a pacemaker is associated with an increase in mortality.

Executive Function in Children and Adolescents with Critical Cyanotic Congenital Heart Disease.

Children and adolescents with critical cyanotic congenital heart disease (CHD) are at risk for deficits in aspects of executive function (EF). The primary aim of this investigation was to compare EF outcomes in three groups of children/adolescents with severe CHD and controls (ages 10-19 years). Participants included 463 children/adolescents with CHD [dextro-transposition of the great arteries (TGA), n=139; tetralogy of Fallot (TOF), n=68; and, single-ventricle anatomy requiring Fontan procedure (SVF), n=145] and 111 controls, who underwent laboratory and informant-based evaluation of EF skills. Rates of EF impairment on D-KEFS measures were nearly twice as high for CHD groups (75-81%) than controls (43%). Distinct EF profiles were documented between CHD groups on D-KEFS tasks. Deficits in flexibility/problem-solving and verbally mediated EF skills were documented in all three CHD groups; visuo-spatially mediated EF abilities were impaired in TOF and SVF groups, but preserved in TGA. Parent, teacher, and self-report ratings on the BRIEF highlighted unique patterns of metacognitive and self-regulatory concerns across informants. CHD poses a serious threat to EF development. Greater severity of CHD is associated with worse EF outcomes. With increased understanding of the cognitive and self-regulatory vulnerabilities experienced by children and adolescents with CHD, it may be possible to identify risks early and provide individualized supports to promote optimal neurodevelopment.

[Primary, single-stage arterial switch operations at a newly-established, comprehensive congenital cardiac center performed in the neonatal age and beyond]. / Újszülöttkorban és késobb végzett primer artériás switchmutétek eredményei egy újonnan létrehozott, átfogó congenitalis szívközpontban.

INTRODUCTION: Outcome of arterial switch operation for transposition of the great arteries with/without ventricular septal defect is a service key-performance-indicator. AIM: The aim of the authors was to assess patient characteristics and parameters in the perioperative course. METHOD: In the setting of a newly-established, comprehensive tertiary-care center, primary complete repair was performed including associated anomalies, e.g. transverse arch repairs. Patients with d-transposition were grouped according to coexistence of ventricular septal defect. RESULTS: 118 arterial switch operations were performed between 2007 and 2014 with 96.62% survival (114/118). Ventricular septal defect and repair of associated anomalies did not yield worse outcome. Left ventricular re-training with late presentation necessitated mechanical circulatory support for 4.5±1.5 days. CONCLUSIONS: D-transposition is suitable for standardization of clinical algorithm and surgical technique. Quality standards contribute to excellent outcomes, minimize complications, and serve as blueprint for other neonatal open-heart procedures. Availability of mechanical circulatory support is key for single-stage left ventricular re-training beyond the neonatal period.