Factors Associated with Growth in a Cohort of Children with Complex Biventricular Congenital Heart Disease.

OBJECTIVES: To evaluate patterns and determinants of longitudinal growth among children requiring complex biventricular repair for congenital heart disease, as well as to assess for associations of growth with early feeding modality, comorbidities, postoperative complications, and socioeconomic characteristics. STUDY DESIGN: A single-institution retrospective cohort study was performed in children born February 1999 to March 2009 with complex congenital heart disease who underwent biventricular repair before age 4 years, defined by Risk Adjustment in Congenital Heart Surgery-1 category 3-5. Clinical characteristics, height, weight, and body mass index (BMI) from ages 2-12 years were collected by chart review. Neighborhood-level socioeconomic data were identified using a geographic information system approach. The adjusted association of covariates with growth outcomes was estimated using multivariable linear regression models using generalized estimating equations. RESULTS: Compared with population growth curves, the cohort (n = 150) trended toward early decrease in age-adjusted weight and height. Early tube feeding was significantly associated with decreased BMI before adolescence (-0.539; 95% CI -1.02, -0.054; P = .029). In addition, other clinical and perioperative characteristics had significant associations with growth, including low birth weight, preoperative tube feeds, need for multiple bypass runs, and diagnosis of feeding disorder. CONCLUSIONS: Early childhood growth in children with complex biventricular repair may be impaired. Early tube feeding was associated with decreased BMI over the course of early childhood, which may indicate a need for continued close nutrition follow-up and support even beyond the duration of tube feeds.

Cardiac magnetic resonance predictors for successful primary biventricular repair of unbalanced complete common atrioventricular canal.

BACKGROUND: Patients with unbalanced common atrioventricular canal can be difficult to manage. Surgical planning often depends on pre-operative echocardiographic measurements. We aimed to determine the added utility of cardiac MRI in predicting successful biventricular repair in common atrioventricular canal. METHODS: We conducted a retrospective cohort study of children with common atrioventricular canal who underwent MRI prior to repair. Associations between MRI and echocardiographic measures and surgical outcome were tested using logistic regression, and models were compared using area under the receiver operator characteristic curve. RESULTS: We included 28 patients (median age at MRI: 5.2 months). The optimal MRI model included the novel end-diastolic volume index (using the ratio of left ventricular end-diastolic volume to total end-diastolic volume) and the left ventricle-right ventricle angle in diastole (area under the curve 0.83, p = 0.041). End-diastolic volume index ≤ 0.18 and left ventricle-right ventricle angle in diastole ≤ 72° yield a sensitivity of 83% and specificity of 81% for successful biventricular repair. The optimal multimodality model included the end-diastolic volume index and the echocardiographic atrioventricular valve index with an area under the curve of 0.87 (p = 0.026). CONCLUSIONS: Cardiac MRI can successfully predict successful biventricular repair in patients with unbalanced common atrioventricular canal utilising the end-diastolic volume index alone or in combination with the MRI left ventricle-right ventricle angle in diastole or the echocardiographic atrioventricular valve index. A prospective cardiac MRI study is warranted to better define the multimodality characteristic predictive of successful biventricular surgery.

Introduction of transcatheter edge-to-edge repair in patients with congenital heart disease at a children's hospital.

BACKGROUND: Atrioventricular valve regurgitation (AVVR) is a devastating complication in children and young adults with congenital heart disease (CHD), particularly in patients with single ventricle physiology. Transcatheter edge-to-edge repair (TEER) is a rapidly expanding, minimally invasive option for the treatment of AVVR in adults that avoids the morbidity and mortality associated with open heart surgery. However, application of TEER in in CHD and in children is quite novel. We describe the development of a peri-procedural protocol including image-derived pre-intervention simulation, with successful application to four patients. AIMS: To describe the initial experience using the MitraClip system for TEER of dysfunctional systemic atrioventricular valves in patients with congential heart disease within a pediatric hospital. METHODS: A standardized screening and planning process was developed using cardiac magnetic resonance imaging, three dimensional echocardiography and both virtual and physical simulation. Procedures were performed using the MitraClip G4 system and patients were clinically followed post-intervention. RESULTS: A series of four CHD patients with at least severe AVVR were screened for suitability for TEER with the MitraClip system: three patients had single ventricle physiology and Fontan palliation, and one had repair of a common atrioventricular canal defect. Each patient had at least severe systemic AVVR and was considered at prohibitively high risk for surgical repair. Each patient underwent a standardized preprocedural screening protocol and image-derived modeling followed by the TEER procedure with successful clip placement at the intended location in all cases. CONCLUSIONS: The early results of our protocolized efforts to introduce TEER repair of severe AV valve regurgitation with MitraClip into the CHD population within our institution are encouraging. Further investigations of the use of TEER in this challenging population are warranted.

Defining the Spectrum of Hypoplastic Left Heart Syndrome (HLHS).

The 2021 International Paediatric and Congenital Cardiac Code and the Eleventh Revision of the International Classification of Diseases provide the following definition for hypoplastic left heart syndrome (HLHS): "Hypoplastic left heart syndrome (HLHS) is defined as a spectrum of congenital cardiovascular malformations with normally aligned great arteries without a common atrioventricular junction, characterized by underdevelopment of the left heart with significant hypoplasia of the left ventricle including atresia, stenosis, or hypoplasia of the aortic or mitral valve, or both valves, and hypoplasia of the ascending aorta and aortic arch." Although HLHS with intact ventricular septum (HLHS + IVS) and HLHS with ventricular septal defect (HLHS + VSD) are different cardiac phenotypes, both of these lesions are part of the spectrum of HLHS.

Imaging of Left Ventricular Hypoplasia.

Left ventricular hypoplasia is a common finding in various forms of congenital heart disease. Echocardiography in the setting of left ventricular hypoplasia must comprehensively assess the size and function of all left-sided structures including the mitral valve, left ventricular outflow tract, aortic valve and aortic arch. Of most importance in any variation of left ventricular hypoplasia is the left ventricular inlet. In neonates, the left ventricular inlet often determines the adequacy of the left ventricle and is the most difficult component to treat surgically.

Fetal Doppler Echocardiographic Assessment Predicts Severe Postnatal Obstruction in Total Anomalous Pulmonary Venous Connection.

BACKGROUND: Obstructed total anomalous pulmonary venous connection (TAPVC) is a form of critical congenital heart disease that usually requires urgent postnatal intervention. Knowing which patients have severe obstruction can aid delivery planning. The authors previously developed a novel quantitative metric of pulmonary venous flow, the pulmonary venous variability index (PVVI). The aim of this study was to test the hypothesis that fetal PVVI and vertical vein Doppler velocities are associated with severe pulmonary vein obstruction postnatally. METHODS: A retrospective cohort study of neonates with prenatally diagnosed TAPVC was performed. Patients who underwent fetal echocardiography at the Children's Hospital of Philadelphia with Doppler interrogation of the vertical vein were included for analysis. Twenty-nine patients met criteria (21 with heterotaxy, 18 with supracardiac TAPVC). The latest gestation fetal echocardiogram was used. Severe pulmonary vein obstruction was defined as preoperative death or urgent surgery or catheter-based intervention (first day of life). Measurements of PVVI, defined as (maximum velocity - minimum velocity)/mean velocity, were made offline. Wilcoxon rank sum models were used to assess the associations of severe obstruction and PVVI and maximum, mean, and minimum velocities. RESULTS: The mean gestational age at the latest fetal echocardiographic examination was 35 weeks (range, 30-39 weeks). Twelve of the 29 patients (41%) met criteria for severe pulmonary vein obstruction. Lower PVVI was associated with greater risk for severe pulmonary venous obstruction (P = .008). The maximum, mean, and minimum velocities in the vertical vein were all significantly associated with severe pulmonary venous obstruction (P = .03, P = .03, and P = .007, respectively). Qualitative assessment of obstruction was not significantly associated with the outcome. Interobserver reliability for all vertical vein Doppler metrics was high (intraclass correlation coefficient > 0.9). CONCLUSIONS: Fetal PVVI and maximum, mean, and minimum velocities are associated with severe postnatal pulmonary vein obstruction in TAPVC. Accurate prediction of obstructed TAPVC could allow safer delivery planning. Further research with larger sample sizes is needed to identify the ideal cutoff values for these Doppler measures.

Dynamic Annular Modeling of the Unrepaired Complete Atrioventricular Canal Annulus.

BACKGROUND: Repair of complete atrioventricular canal (CAVC) is often complicated by atrioventricular valve regurgitation, particularly of the left-sided valve. Understanding the 3-dimensional (3D) structure of the atrioventricular canal annulus before repair may help to inform optimized repair. However, the 3D shape and movement of the CAVC annulus has been neither quantified nor rigorously compared with a normal mitral valve annulus. METHODS: The complete annuli of 43 patients with CAVC were modeled in 4 cardiac phases using transthoracic 3D echocardiograms and custom code. The annular structure was compared with the annuli of 20 normal pediatric mitral valves using 3D metrics and statistical shape analysis (Procrustes analysis). RESULTS: The unrepaired CAVC annulus varied in shape significantly throughout the cardiac cycle. Procrustes analysis visually demonstrated that the average normalized CAVC annular shape is more planar than the normal mitral annulus. Quantitatively, the annular height-to-valve width ratio of the native left CAVC atrioventricular valve was significantly lower than that of a normal mitral valve in all systolic phases (P < .001). CONCLUSIONS: The left half of the CAVC annulus is more planar than that of a normal mitral valve with an annular height-to-valve width ratio similar to dysfunctional mitral valves. Given the known importance of annular shape to mitral valve function, further exploration of the association of 3D structure to valve function in CAVC is warranted.

Nomenclature for Pediatric and Congenital Cardiac Care: Unification of Clinical and Administrative Nomenclature - The 2021 International Paediatric and Congenital Cardiac Code (IPCCC) and the Eleventh Revision of the International Classification of Diseases (ICD-11).

Substantial progress has been made in the standardization of nomenclature for paediatric and congenital cardiac care. In 1936, Maude Abbott published her Atlas of Congenital Cardiac Disease, which was the first formal attempt to classify congenital heart disease. The International Paediatric and Congenital Cardiac Code (IPCCC) is now utilized worldwide and has most recently become the paediatric and congenital cardiac component of the Eleventh Revision of the International Classification of Diseases (ICD-11). The most recent publication of the IPCCC was in 2017. This manuscript provides an updated 2021 version of the IPCCC.The International Society for Nomenclature of Paediatric and Congenital Heart Disease (ISNPCHD), in collaboration with the World Health Organization (WHO), developed the paediatric and congenital cardiac nomenclature that is now within the eleventh version of the International Classification of Diseases (ICD-11). This unification of IPCCC and ICD-11 is the IPCCC ICD-11 Nomenclature and is the first time that the clinical nomenclature for paediatric and congenital cardiac care and the administrative nomenclature for paediatric and congenital cardiac care are harmonized. The resultant congenital cardiac component of ICD-11 was increased from 29 congenital cardiac codes in ICD-9 and 73 congenital cardiac codes in ICD-10 to 318 codes submitted by ISNPCHD through 2018 for incorporation into ICD-11. After these 318 terms were incorporated into ICD-11 in 2018, the WHO ICD-11 team added an additional 49 terms, some of which are acceptable legacy terms from ICD-10, while others provide greater granularity than the ISNPCHD thought was originally acceptable. Thus, the total number of paediatric and congenital cardiac terms in ICD-11 is 367. In this manuscript, we describe and review the terminology, hierarchy, and definitions of the IPCCC ICD-11 Nomenclature. This article, therefore, presents a global system of nomenclature for paediatric and congenital cardiac care that unifies clinical and administrative nomenclature.The members of ISNPCHD realize that the nomenclature published in this manuscript will continue to evolve. The version of the IPCCC that was published in 2017 has evolved and changed, and it is now replaced by this 2021 version. In the future, ISNPCHD will again publish updated versions of IPCCC, as IPCCC continues to evolve.

Congenital polyvalvular disease expands the cardiac phenotype of the RASopathies.

The RASopathies are a group of similar genetic syndromes with cardiovascular abnormalities, characteristic facial features, short stature, abnormalities of the skin and musculoskeletal system, and variable neurodevelopmental challenges. The most common cardiovascular abnormalities include pulmonary valvular stenosis and hypertrophic cardiomyopathy. Congenital polyvalvular disease (CPVD) refers to congenital dysplasia of two or more cardiac valves. We diagnosed a RASopathy in two individuals with CPVD and noted that CPVD in RASopathies has rarely been reported in the literature. Thus, we performed a retrospective chart review and literature review to investigate the association and characterize the phenotype of CPVD in the RASopathies. CPVD was present in 2.5% (n = 6/243) of individuals in our RASopathy cohort. Involvement of two cardiac valves, commonly the aortic and pulmonic valves, was seen in the majority of individuals (6/8; 75%) in our cohort, but only 27% (3/11) of reported CPVD and RASopathy cases in the literature. CPVD should be considered an associated cardiovascular phenotype of the RASopathies, which has implications for diagnosis and management.

Venous Flow Variation Predicts Preoperative Pulmonary Venous Obstruction in Children with Total Anomalous Pulmonary Venous Connection.

BACKGROUND: Identifying preoperative pulmonary venous obstruction in total anomalous pulmonary venous connection is important to guide treatment planning and risk prognostication. No standardized echocardiographic definition of obstruction exists in the literature. Definitions based on absolute velocities are affected by technical limitations and variations in pulmonary venous return. The authors developed a metric to quantify pulmonary venous blood flow variation: pulmonary venous variability index (PVVI). The aim of this study was to demonstrate its accuracy in defining obstruction. METHODS: All patients with total anomalous pulmonary venous connection at a single institution were identified. Echocardiograms were reviewed, and maximum (Vmax), mean (Vmean), and minimum (Vmin) velocities along the pulmonary venous pathway were measured. PVVI was defined as (Vmax - Vmin)/Vmean. These metrics were compared with pressures measured on cardiac catheterization. Echocardiographic measures were then compared between patients with and without clinical preoperative obstruction (defined as a need for preoperative intubation, catheter-based intervention, or surgery within 1 day of diagnosis), as well as pulmonary edema by chest radiography and markers of lactic acidosis. One hundred thirty-seven patients were included, with 22 having catheterization pressure recordings. RESULTS: Vmax and Vmean were not different between patients with catheter gradients ≥ 4 and < 4 mm Hg, while PVVI was significantly lower and Vmin higher in those with gradients ≥ 4 mm Hg. The composite outcome of preoperative obstruction occurred in 51 patients (37%). Absolute velocities were not different between patients with and without clinical obstruction, while PVVI was significantly lower in patients with obstruction. All metrics except Vmax were associated with pulmonary edema; none were associated with blood gas metrics. CONCLUSIONS: The authors developed a novel quantitative metric of pulmonary venous flow, which was superior to traditional echocardiographic metrics. Decreased PVVI was highly associated with elevated gradients measured by catheterization and clinical preoperative obstruction. These results should aid risk assessment and diagnosis preoperatively in patients with total anomalous pulmonary venous connection.

Left Valvar Morphology Is Associated With Late Regurgitation in Atrioventricular Canal Defect.

BACKGROUND: Left atrioventricular valve regurgitation (LAVVR) after atrioventricular canal (AVC) repair remains a significant cause of morbidity. Papillary muscle arrangement may be important. To investigate the implications of left mural leaflet morphology, we examined anatomic characteristics of the LAVV to determine possible associations with postoperative LAVVR. METHODS: All patients with biventricular AVC repair at our institution between January 1, 2011, and December 31, 2016, with necessary imaging were retrospectively reviewed. We assessed papillary muscle structure and novel measures of the left mural leaflet from preoperative echocardiograms and the degree of LAVVR from the first and last available follow-up echocardiograms. Associations with degree of early and late postoperative LAVVR were assessed with t tests, analysis of variance, or χ2 or Fisher exact tests, and multivariable logistic regression. RESULTS: There were 58 of 156 patients (37%) with significant (moderate or severe) early postoperative LAVVR, and 30 of 93 (32%) had significant LAVVR after 6 or more months. Fewer patients with closely spaced or asymmetric papillary muscles had moderate or severe late LAVVR vs those with widely spaced papillary muscles (17% vs 40%, P = .019). Controlling for weight at operation, genetic syndromes, and bypass time, widely spaced papillary muscles increased the odds ratio for late LAVVR to 3.6 (P = .026). Larger mural leaflet area was also associated with late LAVVR on univariable (P = .019) and multivariable (P = .023) analyses. One-third of patients with significant late LAVVR had no significant early postoperative regurgitation. CONCLUSIONS: Mural leaflet and papillary muscle anatomy are associated with late LAVVR after AVC repair. Late regurgitation can develop in the absence of early LAVVR, suggesting different mechanisms.

Clinical Innovation: A Multidisciplinary Program for the Diagnosis and Treatment of Systemic Hypertension in Children and Adolescents.

Pediatric systemic hypertension (HTN) is underdiagnosed and undertreated. The Divisions of Cardiology and Nephrology at our institution developed a comprehensive outpatient HTN program to (1) screen children at risk for HTN, (2) assess cardiovascular health, and (3) optimize medical management. We report our findings during all initial visits (n = 304) from December 2011 to September 2018. Of the cohort, 38% were obese and 36% reported little to no exercise. More than half of patients ≥11 years old did not have recommended lipid screening. When evaluating ambulatory blood pressure monitoring results, clinic blood pressure did not accurately diagnose patients with or without HTN and many patients on antihypertensive medications were inadequately treated. Visit recommendations included addition of or changes to antihypertensive medication in 35% of patients. A multidisciplinary program dedicated to pediatric HTN helps screen patients who are at risk. Ambulatory blood pressure monitoring identifies HTN in patients with normal clinic blood pressure and those on antihypertensive medication.

Pulmonary artery banding in complete atrioventricular septal defect.

OBJECTIVES: To analyze outcomes after pulmonary artery banding (PAB) in complete atrioventricular septal defect (AVSD), with a focus on surgical pathway outcome and timing, survival, and atrioventricular valve function. METHODS: PAB was performed in 50 of 474 infants (11%) from 28 institutions between 2012 and 2018 at a median age of 1.1 months. The median duration of follow-up was 2.1 years. Atrioventricular valve function was assessed by review of pre-PAB and predischarge echocardiograms (median, 9 days postoperatively). Competing-risks methodology was used to analyze the risks for biventricular repair, univentricular repair, and death. RESULTS: At 2 years, the proportions of patients who underwent biventricular repair, univentricular repair, and death were 68%, 13%, and 12%, respectively, with 8% awaiting definitive repair. After PAB, atrioventricular valve regurgitation decreased in 14 infants and increased in 10, but the distribution of regurgitation severity did not change significantly in the total cohort or subgroups. The intended management plan at PAB was deferred biventricular/univentricular decision (23 infants), 2-stage biventricular repair (24 infants), and univentricular repair (3 infants). Among the 24 infants intended for biventricular repair, 23 achieved biventricular repair and 1 died before repair. Survival at 4 years after biventricular repair among patients with previous PAB (93%) was similar to the 4-year survival of the patients who underwent primary biventricular repair (91%; n = 333). CONCLUSIONS: PAB is a successful strategy in complete AVSD to bridge to biventricular repair and has similar post-biventricular repair survival to primary biventricular repair. Changes in atrioventricular valve regurgitation after PAB were variable.

Extracorporeal membrane oxygenation as a novel management strategy for interventricular septal hematoma following ventricular septal defect repair.

OBJECTIVES: Interventricular septal hematoma (IVSH) is a rare complication, which may result from ventricular septal defect (VSD) repair. IVSH can result in conduction and/or hemodynamic abnormalities related to impaired ventricular filling or outflow tract obstruction. We report the novel use of extracorporeal membrane oxygenation (ECMO) for management. METHODS: Echocardiography reports (January 1980 to December 2016) were searched for the term "hematoma" in our institutional database and reviewed to determine appropriate cases. Charts and imaging (reports) data were abstracted. All intraoperative and select postoperative echocardiograms were reread by a pediatric cardiologist. RESULTS: N = 12 patients with IVSH. Mean age and weight at surgery were 59 ± 41 days and 3.4 (2.9-5.1) kg, respectively, while the most frequent diagnosis was tetralogy of Fallot. Although all patients had intraoperative transesophageal echocardiography (TEE), only 55% (6 of 11, missing [m] = 1) of IVSH were discovered intraoperatively. Of the 5 patients not discovered intraoperatively (m = 1), IVSH was postoperatively detected secondary to arrhythmia/decompensation by echocardiogram 10.1 ± 7.9 hours postoperatively. Five patients (42%) were managed with ECMO (1 unable to separate from bypass). Overall mortality was 33%. For patients in whom ECMO was used, 2 of 5 (40%) survived. Mean time to IVSH resolution in all survivors was 20 ± 185 days. CONCLUSIONS: IVSH from VSD repair can result in clinical decompensation and mortality. This may relate to the high proportion missed intraoperatively. ECMO should be considered an important modality, which can allow for IVSH resolution. However, considerations must be made to allow for appropriate anticoagulation to avoid hematoma expansion and repeat imaging during ECMO to continually assess the interventricular septum.

Preoperative Clinical and Echocardiographic Factors Associated with Surgical Timing and Outcomes in Primary Repair of Common Atrioventricular Canal Defect.

In complete atrioventricular canal defect (CAVC), there are limited data on preoperative clinical and echocardiographic predictors of operative timing and postoperative outcomes. A retrospective, single-center analysis of all patients who underwent primary biventricular repair of CAVC between 2006 and 2015 was performed. Associated cardiac anomalies (tetralogy of Fallot, double outlet right ventricle) and arch operation were excluded. Echocardiographic findings on first postnatal echocardiogram were correlated with surgical timing and postoperative outcomes using bivariate descriptive statistics and multivariable logistic regression. 153 subjects (40% male, 84% Down syndrome) underwent primary CAVC repair at a median age of 3.3 (IQR 2.5-4.2) months. Median postoperative length of stay (LOS) was 7 (IQR 5-15) days. Eight patients (5%) died postoperatively and 24 (16%) required reoperation within 1 year. On multivariable analysis, small aortic isthmus (z score < - 2) was associated with early primary repair at < 3 months (OR 2.75, 95% CI 1.283-5.91) and need for early reoperation (OR 3.79, 95% CI 1.27-11.34). Preoperative ventricular dysfunction was associated with higher postoperative mortality (OR 7.71, 95% CI 1.76-33.69). Other factors associated with mortality and longer postoperative LOS were prematurity (OR 5.30, 95% CI 1.24-22.47 and OR 5.50, 95% CI 2.07-14.59, respectively) and lower weight at surgery (OR 0.17, 95% CI 0.04-0.75 and OR 0.55, 95% CI 0.35-0.85, respectively). Notably, preoperative atrioventricular valve regurgitation and Down syndrome were not associated with surgical timing, postoperative outcomes or reoperation, and there were no echocardiographic characteristics associated with late reoperation beyond 1 year after repair. Key preoperative echocardiographic parameters helped predict operative timing and postoperative outcomes in infants undergoing primary CAVC repair. Aortic isthmus z score < - 2  was associated with early surgical repair and need for reoperation, while preoperative ventricular dysfunction was associated with increased mortality. These echocardiographic findings may help risk-stratified patients undergoing CAVC repair and improve preoperative counseling and surgical planning.

Repair of Total Anomalous Pulmonary Venous Connection: Risk Factors for Postoperative Obstruction.

BACKGROUND: Pulmonary venous obstruction after repair of total anomalous pulmonary venous connection (TAPVC) results in substantial morbidity and mortality. Risk factors for postoperative obstruction remain ambiguous. In addition, the existing literature has no standard definition for preoperative obstruction, making patient counseling difficult. METHODS: All patients undergoing repair of TAPVC at our institution from January 1, 2006, to October 23, 2017, were identified. The primary outcome was the development of postoperative obstruction, analyzed as a time-to-event outcome. Clinical information was extracted to assess risk factors. Degrees of preoperative obstruction were defined based on echocardiographic, catheterization, and clinical findings. Univariable and multivariable Cox proportional hazard regression methods were used to identify factors associated with the primary outcome. RESULTS: During the study interval, 119 patients underwent repair of TAPVC (40% single ventricle), and postoperative obstruction developed in 25 patients (21%). Risk factors associated with obstruction were heterotaxy syndrome, single-ventricle heart disease, additional procedures at the time of vein repair, mixed-type TAPVC, and preoperative obstruction. Having even mild preoperative obstruction (≥1.2 m/s by Doppler echocardiography) was predictive of postoperative obstruction. A multivariable model showed mixed-type TAPVC and the presence of preoperative obstruction were associated with a more than twofold greater hazard of obstruction. CONCLUSIONS: TAPVC in the setting of heterotaxy and a single ventricle remains challenging, with high rates of postoperative obstruction. Mixed-type TAPVC is an independent risk factor for postoperative obstruction, particularly in patients with isolated TAPVC. Even mild preoperative obstruction is a risk factor for postoperative obstruction. These results may help risk-stratify TAPVC patients.