Unbalanced Atrioventricular Septal Defect Research Articles

Fetal single ventricle journey to first postnatal procedure: a multicentre UK cohort study

ObjectivesUK single ventricle (SV) palliation outcomes after first postnatal procedure (FPP) are well documented. However, survival determinants from fetal diagnosis to FPP are lacking. To better inform parental-fetal counselling, we...

Current follow-up results of Cyanotic Congenital Heart Diseases detected during Pregnancy in a specific Region

Background/Aims: Congenital heart disease (CHD) is the main cause of death in infants among congenital anomalies. Fetal echocardiography is important for the diagnosis and treatment plan of congenital heart diseases in the prenatal period. This study aimed to retrospectively screen the follow-up and treatment results of cyanotic CHD patients detected on fetal echocardiography. Methods: Fetal echocardiography results were scanned from the hospital record system. Data of fetuses with major cardiac anomalies and cyanotic CHD were examined retrospectively. Results: Fetal echocardiography was performed on 420 pregnant women between July 2020 and April 2023. Major cardiac anomalies and cyanotic heart disease were detected in the fetuses of 40 pregnant women (9.5%) out of 420. The median age of the pregnant women was 29 (19-41 years). The median gestational age at check-up was 23 weeks (22-28 weeks). 9/40 pregnant women (22.5%) had risk factors. The most common cyanotic congenital heart diseases were hypoplastic left heart syndrome (HLHS) and unbalanced complete atrioventricular septal defects (AVSDs) with obstructive lesions of the right or left ventricle. Three fetuses (7.5%) with heart failure findings died intrauterine. Two fetuses with HLHS and critical aortic stenosis (AS) died before being operated on. A patient with complete AVSD, hypoplasia of the left heart chambers, AS, and severe aortic coarctation died due to sepsis during the post-operative follow-up period. Chromosome analysis was performed in 8 patients. Down syndrome was detected in 3 of the patients with complete AVSD. 22q11 deletion and DiGeorge Syndrome were detected in 2 patients with tetralogy of Fallot. Conclusions: Congenital heart diseases and rhythm problems can be safely detected with fetal echocardiography. It is beneficial to perform a fetal echo scan at the appropriate gestational week, especially in fetuses with risk factors and in whom the four chambers view cannot be seen.

Rescuing the Right Ventricle: Mechanical Support After Pediatric Heart Transplantation

BackgroundRight ventricular (RV) failure after heart transplantation (HT) is common in those with pretransplantation elevated pulmonary vascular resistance (PVR). Mechanical circulatory support has been used as a bridge to recovery, with mixed outcomes. We describe a patient with failed single-ventricle palliation in whom severe RV failure developed after HT. We review the current literature and outline our post-HT strategy. MethodsAn infant with trisomy 21, severely unbalanced right dominant atrioventricular septal defect, and hypoplastic aortic arch was palliated with a hybrid procedure. At 6 months of age, cardiac catheterization measured PVR index of 5.47 Wood units × m2 on maximal medical therapy. The patient was deemed unsuitable for second-stage palliation and underwent HT at 18 months of age. Despite preemptive medical therapies, acute RV failure developed, necessitating extracorporeal membrane oxygenation. He was quickly converted to main pulmonary artery to left atrial cannulation. Unloaded RV function normalized; he was weaned from support and discharged home 5 weeks after HT. ResultsFailure of medical therapy in RV failure after HT requires escalation to mechanical circulatory support. We review the literature on RV failure and support after HT. We also describe a novel cannulation strategy to provide a reliable way to directly reduce RV afterload, to allow physiologic training of the right ventricle to a higher PVR, and to maintain normal left ventricular coupling and loading. ConclusionsIn pediatric patients with elevated PVR undergoing HT, advanced therapies can be used effectively to treat acute RV failure. Unique cannulation strategies may play a role in improving survival of similar patients.

Biventricular repair using subvalvular techniques for unbalanced atrioventricular septal defect.

We report the case of a 19-month-old girl with a right-dominant unbalanced atrioventricular septal defect and severe right-sided atrioventricular valve regurgitation who underwent biventricular repair using basal chordae resection, artificial chordae reconstruction and a left-sided atrioventricular valvuloplasty. At 14-month postoperative follow-up, the patient had minimal heart failure, gained weight and adapted to biventricular circulation.

Echocardiographic Parameters for Risk Prediction in Borderline Right Ventricle: Review with Special Emphasis on Pulmonary Atresia with Intact Ventricular Septum and Critical Pulmonary Stenosis.

The aim of the present review is to highlight the strengths and limitations of echocardiographic parameters and scores employed to predict favorable outcome in complex congenital heart diseases (CHDs) with borderline right ventricle (RV), with a focus on pulmonary atresia with intact ventricular septum and critical pulmonary stenosis (PAIVS/CPS). A systematic search in the National Library of Medicine using Medical Subject Headings and free-text terms including echocardiography, CHD, and scores, was performed. The search was refined by adding keywords "PAIVS/CPS", Ebstein's anomaly, and unbalanced atrioventricular septal defect with left dominance. A total of 22 studies were selected for final analysis; 12 of them were focused on parameters to predict biventricular repair (BVR)/pulmonary blood flow augmentation in PAIVS/CPS. All of these studies presented numerical (the limited sample size) and methodological limitations (retrospective design, poor definition of inclusion/exclusion criteria, variability in the definition of outcomes, differences in adopted surgical and interventional strategies). There was heterogeneity in the echocardiographic parameters employed and cut-off values proposed, with difficultly in establishing which one should be recommended. Easy scores such as TV/MV (tricuspid/mitral valve) and RV/LV (right/left ventricle) ratios were proven to have a good prognostic accuracy; however, the data were very limited (only two studies with <40 subjects). In larger studies, RV end-diastolic area and a higher degree of tricuspid regurgitation were also proven as accurate predictors of successful BVR. These measures, however, may be either operator and/or load/pressure dependent. TV Z-scores have been proposed by several authors, but old and heterogenous nomograms sources have been employed, thus producing discordant results. In summary, we provide a review of the currently available echocardiographic parameters for risk prediction in CHDs with a diminutive RV that may serve as a guide for use in clinical practice.

A case report of Y-shaped bi-directional Fontan procedure: promising long-term outcomes for single ventricle physiology patients

BackgroundAchieving optimal hepatic factor distribution and total cavopulmonary resistance is crucial for long-term outcomes in single ventricle palliation patients. Y-shaped Gore-Tex Fontan procedure redirects hepatic drainage to both the right and left pulmonary arteries. The aim of this approach is to achieve bilateral pulmonary distribution of hepatic factors and reduce the risk of arteriovenous malformations that can develop in single-ventricle patients.Case presentationWe present a unique case of a 20 years old female with symptoms of heart failure, who has a history of complex heterotaxy with polysplenia, interrupted Inferior vena-cava, and double outlet right ventricle with unbalanced atrio-ventricular septal defect, d-malposed great arteries, and pulmonary atresia. Fenestrated Y-shaped Gore-Tex Fontan procedure was successfully done which was confirmed by performing cardiac CT angiography.ConclusionsStudies have shown that achieving balanced hepatic factor distribution and low resistance in the Fontan pathway can improve long-term outcomes. This procedure has demonstrated positive results in terms of oxygen saturation and reduced asymmetric blood flow distribution. Level of Evidence Level 4, Case Report.

Preoperative versus postoperative survival in patients with univentricular heart: a nationwide, retrospective study of patients born in 1990–2015

ObjectivesFew data exist on mortality among patients with univentricular heart (UVH) before surgery. Our aim was to explore the results of intention to perform surgery by estimating preoperative vs postoperative...

Hospital resource utilization in a national cohort of functionally single ventricle patients undergoing surgical treatment

ObjectiveThe study objective was to provide a detailed overview of health resource use from birth to 18 years old for patients with functionally single ventricles and identify associated risk factors. MethodsAll patients with functionally single ventricles treated between 2000 and 2017 in England and Wales were linked to hospital and outpatient records using data from the Linking AUdit and National datasets in Congenital HEart Services project. Hospital stay was described in yearly age intervals, and associated risk factors were explored using quantile regression. ResultsA total of 3037 patients with functionally single ventricles were included, 1409 (46.3%) undergoing a Fontan procedure. During the first year of life, the median days spent in hospital was 60 (interquartile range, 37-102), mostly inpatient days, mirroring a mortality of 22.8%. This decreases to between 2 and 9 in-hospital days/year afterward. Between 2 and 18 years, most hospital days were outpatient, with a median of 1 to 5 days/year. Lower age at the first procedure, hypoplastic left heart syndrome/mitral atresia, unbalanced atrioventricular septal defect, preterm birth, congenital/acquired comorbidities, additional cardiac risk factors, and severity of illness markers were associated with fewer days at home and more intensive care unit days in the first year of life. Only markers of early severe illness were associated with fewer days at home in the first 6 months after the Fontan procedure. ConclusionsHospital resource use in functionally single ventricle cases is not uniform, decreasing 10-fold during adolescence compared with the first year of life. There are subsets of patients with worse outcomes during their first year of life or with persistently high hospital use throughout their childhood, which could be the target of future research.

Palliation of a Heterotaxy Single Ventricle Neonate with Pulmonary Atresia and Obstructed TAPVR

Patients born with obstructed total anomalous pulmonary venous return have a high risk of morbidity and mortality in the neonatal period, which only increases when combined with single ventricle physiology and non-cardiac congenital anomalies such as heterotaxy syndrome. Despite advances in management of congenital heart disease, surgery within the first weeks of life to repair the pulmonary venous connection and establish pulmonary blood flow with a systemic-to-pulmonary shunt has historically led to disappointing outcomes. A multidisciplinary approach with pediatric interventional cardiology and cardiac surgery is required to reduce morbidity and mortality in this extremely high-risk patient population. Extending the time between birth and cardiac surgery can lessen postoperative complications and mortality risk, especially in patients with abnormal thoracoabdominal relationships. Our team was able to successfully utilize transcatheter stent placement in a vertical vein and patent ductus arteriosus to delay and stage cardiac surgeries in an infant born with obstructed total anomalous pulmonary venous return, unbalanced atrioventricular septal defect with pulmonary atresia and heterotaxy, thus reducing the morbidity and mortality associated with this diagnosis.

Outcome after stage 1 palliation in non-hypoplastic left heart syndrome patients as a univentricular palliation.

Studies focused on infants with univentricular heart undergoing stage I palliation other than the Norwood procedure remain a topic of great interest. This study evaluated the outcome of infants who underwent systemic to pulmonary shunt (SPS) or pulmonary artery banding (PAB). Infants who underwent SPS or PAB as stage I palliation between 1994 and 2019 were included. Survival and late systemic ventricular function were evaluated. Out of 242 patients, 188 underwent SPS (77.7%) and 54 PAB (22.3%). Main diagnosis includedtricuspid atresia, unbalanced atrioventricular septal defects, double inlet left ventricles and single ventricles with other morphology. Thirty-eight patients died before stage II palliation (15.7%). Stage II palliation was performed in 182 patients (75.2%), and mortality between stages II and III was 11 (5.6%). Stage III palliation was performed in 160 (66.1%) patients. Survival at 1, 5 and 15 years after stage I procedure was 81.9, 77.1 and 76.2%, respectively, and similar between both procedures (P = 0.97). Premature birth [P = 0.03, hazard ratio (HR) = 2.1], heterotaxy (P = 0.006, HR = 2.4) and dominant right ventricle (P = 0.015, HR = 2.2) were factors associated to mortality. Unbalanced atrioventricular septal defect (P = 0.005, HR = 4.6) was a factor associated to systemic ventricular dysfunction. In patients with univentricular heart who underwent SPS and PAB as stage I palliation, survival at 15 years was 76%, regardless of th chosen approach. Premature birth, heterotaxy and dominant right ventricle wereassociated to mortality.

Hypoplastic Left Ventricle: Definition, Morphology, and Classification of the Cardiac Phenotypes.

A prior manuscript provided information about hypoplastic left heart syndrome (HLHS) and related malformations, including definitions, morphology, and classification, based on the 2021 International Paediatric and Congenital Cardiac Code (IPCCC) and the Eleventh Revision of the International Classification of Diseases (ICD-11). This manuscript provides information about the related cardiac phenotypes associated with "hypoplastic left ventricle" that might be suitable for biventricular repair, including definitions, morphology, and classification of the cardiac phenotypes of the following four congenital cardiac malformations that can all include a hypoplastic left ventricle: (1) hypoplastic left heart complex (HLHC), (2) critical aortic stenosis with left ventricular hypoplasia, (3) aortic atresia + ventricular septal defect, and (4) hypoplastic left ventricle with severely unbalanced atrioventricular septal defect.

Impact of Total Anomalous Pulmonary Venous Connection in Staged Single Ventricle Palliation

BackgroundTotal anomalous pulmonary venous connection (TAPVC) with a functional single ventricle is a risk factor for mortality during staged palliation. This study aimed to assess TAPVC’s impact on staged palliation outcomes. MethodsIn a total of 602 patients with a functional single ventricle who underwent stage 1 palliation (S1P) at our center between 2001 and 2020, 39 (6.5%) patients were associated with TAPVC. Median age at S1P was 12.0 (interquartile range, 7-21) days with a body weight of 3.1 (interquartile range, 2.8-3.6) kg. Outcomes during staged palliation were compared with the remaining 563 patients without TAPVC. Risk factors for mortality were identified using a Cox proportional hazards regression model. ResultsPrimary diagnosis in functional single-ventricle patients with TAPVC included hypoplastic left heart syndromes (n = 13), unbalanced atrioventricular septal defects (n = 12) tricuspid atresias (n = 2), double inlet left ventricle (n = 1), and others (n = 11). Types of TAPVC were supracardiac (n = 21), cardiac (n = 10), infracardiac (n = 6), and mixed (n = 2). Pulmonary venous obstruction (PVO) was associated in 19 (49%) patients. S1Ps included Norwood (n = 13), aortopulmonary shunt (n = 21), and pulmonary artery banding (n = 5). Thirty-day mortality after S1P was significantly increased in patients with TAPVC vs without TAPVC (43.6% vs 16.3%; P < .001). After bidirectional cavopulmonary shunt and total cavopulmonary connection procedures, mortality was low in both groups, and no statistically significant differences were found. Correction of TAPVC at the time of S1P was not found to be a significant risk factor in univariable Cox regression analysis. In univariate and multivariate analysis, PVO was identified as an independent risk factor for mortality in patients with TAPVC (P < .001). ConclusionsOverall survival is lower in TAPVC single-ventricle patients than in non-TAPVC patients. Most deaths after S1P were associated with TAPVC, but not after S2P. PVO is a mortality risk factor in TAPVC patients.

Outcomes of bidirectional Glenn surgery done without prior cardiac catheterization

BackgroundCardiac catheterization is usually done routinely in patients with univentricular hearts before palliative Bidirectional Glenn (BDG) surgery. The objective of this study was to compare the outcomes of patients with physiological univentricular hearts and restrictive pulmonary flow that did not undergo routine cardiac catheterization before BDG with the patients that did have cardiac catheterization done. We retrospectively reviewed the data of all patients with single ventricle physiology and restrictive pulmonary blood flow who underwent BDG surgery from January 2016 till December 2020. Patients were divided into two groups: the catheterization and the non-catheterization groups.ResultsOut of 93 patients, 25 (27%) underwent BDG surgery without prior cardiac catheterization. The median age of patients was ten months, interquartile range (IQR) was 5–18 months. Tricuspid atresia represented 36% of the non-catheterization group, while unbalanced atrioventricular septal defect and hypoplastic left heart syndrome represented 19% and 17.6% of the catheterization group. No patients in the catheterization group were excluded from further BDG surgery based on the catheterization data. Moreover, no significant differences were found between the patients' groups regarding the length of hospital stay, length of intensive care unit stay, postoperative oxygen saturation, or survival (P = 0.266, P = 0.763, P = 0.543, P = 0456).ConclusionsAlthough pre-BDG cardiac catheterization is the routine and standard practice, in certain situations, some patients with single ventricle physiology and restrictive pulmonary blood flow may go directly to BDG without cardiac catheterization if noninvasive imaging is satisfactory on a case-by-case basis and according to center experience. Pre-BDG catheterization could be reserved for patients with limited echocardiographic studies, high-risk patients, or those indicated for catheter intervention before BDG surgery.

Common arterial trunk in functionally univentricular hearts: a case series.

The association of a univentricular heart defect with common arterial trunk is extremely rare. There is a lack of population-based outcome studies reported in the literature. The hospital records, echocardiographic and other imaging modality data, outpatients' records, operation notes, and other electronic data were reviewed. Patients were reviewed, and the final outcomes of surgery were observed. Six cases (two males) with common arterial trunk presented over a 30-year period. Five had a complete unbalanced atrioventricular septal defect (83%) and one (17%) had tricuspid atresia associated with common arterial trunk. All had antenatal diagnosis. Two cases (33%) were excluded from initial surgical palliation due to Trisomy 21 in one and severe truncal valve regurgitation in one. Initial surgical palliation was performed in four cases (67%) at median age of 31 days (2-60) and consisted of disconnection and reconstruction of the pulmonary arteries and establishing controlled pulmonary blood flow. There were no early deaths. Conversion to cavopulmonary shunt was not possible in two due to severe airway problems in one and pulmonary arteries anatomy in one. They died at 11 and 16 months, respectively. Two patients (33%) underwent cavopulmonary shunt with 1 (17%) being alive at 18 months - 12 months after cavopulmonary shunt. The second patient proceeded to Fontan completion at 19 months but required catheter takedown 3 months later and died 3.5 years later. Univentricular hearts with common arterial trunk carry extremely poor short- to medium-term outcomes. This should inform antenatal and postnatal counselling and decision-making.

Clinical progress note: Noncardiac complications in adults with congenital heart disease.

Clinical progress note: Noncardiac complications in adults with congenital heart disease.

Ventricular Assist Device (VAD) Implantation in a Patient with Complex Congenital Heart Disease (CHD)

<h3>Introduction</h3> VAD implantation in complex CHD patients presents physiologic and anatomic challenges. Few such cases have been described. <h3>Case Report</h3> We report a 41-year-old man with a history of dextrocardia, unbalanced atrioventricular (A-V) septal defect, single ventricle, heterotaxy with right atrial isomerism and asplenia, bilateral superior vena cava, pulmonic stenosis, and systemic hypertension. He had undergone surgical palliation including bilateral BT shunts (age 3 months and 7 years) and central aortopulmonary shunt at age 13 years. At age 14 years, he underwent bilateral bidirectional Glenn and extracardiac Fontan repair, followed by mechanical A-V valve replacement at age 21 years and epicardial pacemaker placement for paroxysmal atrial tachycardia (AT). He had recurrent heart failure hospitalizations requiring inotropes. Echocardiography now demonstrated moderate aortic regurgitation. Cardiac catheterization on milrinone and dobutamine found elevated Fontan pressures to 21 mmHg (panel A), reduced cardiac index to 1.4 L/min/m², normal pulmonary vascular resistance and no transhepatic gradient. An intra-aortic balloon pump was placed with improvement of his Fontan pressures to 17 mmHg. However, he subsequently developed refractory AT and cardiogenic shock. Due to cardiac deterioration, he underwent urgent HeartMate3 implantation and aortic valve repair with Park stitch (B: pre-op; C: post-op image) as a bridge to transplant. Surgical approach was an upper hemisternotomy and an anterior right thoracotomy at the 6th intercostal space. His course was complicated by postoperative bleeding requiring re-exploration of the chest, as well as acute kidney injury requiring temporary hemodialysis with subsequent renal recovery. He was transferred to acute rehab 3 weeks after surgery and was discharged home on guideline-directed medical therapy. <h3>Summary</h3> We report an adult patient with dextrocardia, Fontan repair, and single ventricle who underwent successful VAD implantation.

Echocardiographic scores for biventricular repair risk prediction of congenital heart disease with borderline left ventricle: a review.

The aim of this review is to highlight the strengths and limitations of major echocardiographic biventricular repair (BVR) prediction models for borderline left ventricle (LV) in complex congenital heart disease (CHD). A systematic search in the National Library of Medicine for Medical Subject Headings and free text terms including echocardiography, CHD, and scores, was performed. The search was refined by adding keywords for critical aortic stenosis (AS), borderline LV, complex left ventricular outflow tract (LVOT) obstruction, hypoplastic left heart syndrome/complex (HLHS/HLHC), and unbalanced atrio-ventricular septal defects (uAVSD). Fifteen studies were selected for the final analysis. We outlined what echocardiographic scores for different types of complex CHD with diminutive LV are available. Scores for CHD with LVOT obstruction including critical AS, HLHS/HLHC, and aortic arch hypoplasia have been validated and implemented by several studies. Scores for uAVSD with right ventricle (RV) dominance have also been established and implemented, the first being the atrioventricular valve index (AVVI). In addition to AVII, both LV/RV inflow angle and LV inflow index have all been validated for the prediction of BVR. We conclude with a discussion of limitations in the development and validation of each of these scores, including retrospective design during score development, heterogeneity in echocardiographic parameters evaluated, variability in the definition of outcomes, differences in adopted surgical and Interventional strategies, and institutional differences. Furthermore, scores developed in the past two decades may have little clinical relevance now. In summary, we provide a review of echocardiographic scores for BVR in complex CHD with a diminutive LV that may serve as a guide for use in modern clinical practice.

The Timing and Mechanisms of AV Valve Failure in Children and Adults With Unbalanced Atrioventricular Septal Defect

Atrioventricular valve regurgitation (AVVR) is common in children with unbalanced atrioventricular septal defect (uAVSD) undergoing single ventricle palliation and is associated with increased mortality and morbidity. The time to onset and mechanisms of significant AVVR in uAVSD have not been well characterised. We aimed to define the time to onset and mechanisms of ≥ moderate AVVR in uAVSD.

Common Arterial Trunk Associated with Functionally Univentricular Heart: Anatomical Study and Review of the Literature.

Common arterial trunk (CAT) is a rare congenital heart disease that is commonly included into the spectrum of conotruncal heart defects. CAT is rarely associated with functionally univentricular hearts, and only few cases have been described so far. Here, we describe the anatomical characteristics of CAT associated with a univentricular heart diagnosed in children and fetuses referred to our institution, and we completed the anatomical description of this rare condition through an extensive review of the literature. The complete cohort ultimately gathered 32 cases described in the literature completed by seven cases from our unit (seven fetuses and one child). Four types of univentricular hearts associated with CAT were observed: tricuspid atresia or hypoplastic right ventricle in 16 cases, mitral atresia or hypoplastic left ventricle in 12 cases, double-inlet left ventricle in 2 cases, and unbalanced atrioventricular septal defect in 9 cases. Our study questions the diagnosis of CAT as the exclusive consequence of an anomaly of the wedging process, following the convergence between the embryonic atrioventricular canal and the common outflow tract. We confirm that some forms of CAT can be considered to be due to an arrest of cardiac development at the stages preceding the convergence.

Unbalanced atrioventricular septal defect with dominant right ventricle: diagnostic criteria, indications for biventricular correction, and results. A clinical observation series

Relevance: Surgical treatment for congenital heart disease (CHD) with borderline left ventricle (LV) dimensions is one of the most challenging issues in current pediatric cardiac surgery. Despite the prevailing general trend to the expansion of indications for biventricular repair of an unbalanced atrioventricular septal defect (AVSD) with a dominant right ventricle (RV), the diagnostic criteria for imbalance, feasibility of radical repair and its functional results are intensively discussed in the literature.Aim: To present quantitative criteria for the assessment of the LV size which could serve as an indication for biventricular repair of the right dominant unbalanced AVSD.Materials and methods: We present a series of 4 patients with AVSD and dominant RV, who underwent radical repair of the defect. The mean age of the patients was 2.4 years, and 3 of 4 had concomitant CHD: tetralogy of Fallot, double outlet right ventricle with pulmonary artery stenosis, and moderate hypoplasia of the aortic arch with subaortic stenosis. Three of 4 patients had previously undergone palliative interventions: two of them – pulmonary bending, one, the first stage of univentricular repair (atrioseptostomy, cavopulmonary anastomosis). Two children had been diagnosed with Down syndrome. The mean left ventricular end diastolic diameter (LVEDD) at baseline was 17.9 mm, corresponding to Z score of -5.4.Results: All four patients underwent biventricular repair of the defect with a two-patch technique. In one case, it was supplemented with placement of the pulmonary trunk homograft prosthesis, in the other with pulmonary valve commissurotomy and cavopulmonary anastomosis due to moderate tricuspid valve stenosis and in the third case the mitral valve was replaced. In 3 patients pacemaker implantation was performed. The criterion for feasibility of complete septation was the ratio of the longitudinal dimensions of the left and right ventricles (LAR &gt; 0.7), confirmed by computed tomography performed before the surgery. The mean LVEDD after surgery was 28.3 mm, corresponding to Z score of -0.8. At the time of the hospital discharge, the left and right atrioventricular valves insufficiency did not exceed 2 and 1 degrees, respectively.Conclusion: Computed tomography allows for accurate measurement and comparison of the longitudinal dimensions of the heart ventricles with LAR index as a tool for assessment of the LV size before the biventricular repair. An additional prospective study is required to objectify the data obtained and identify predictors of an unfavorable outcome of radical repair in patients with right dominant unbalanced AVSD.