Atrioventricular Canal Research Articles

Large Ostium Primum Interatrial Septum Defect in Asymptomatic Adult Athlete with Mitral Valve Prolapse and New Onset of Atrial Fibrillation

A large spectrum of congenital cardiac malformations can be the consequence of deficient formation of the embryonic atrioventricular canal by the endocardial cushions [1]. Among them, together with bicuspid aortic valve and mitral valve prolapse (MVP) [2], atrial septal defects (ASD) are one of the most frequent congenital heart diseases in adulthood. Differently from patients with secundum defects, ostium primum ASD are rarely reported in adulthood because those patients often require medical attention in pediatric age due to severity of symptoms. In ostium primum defect, in addition to the septal defect, the atrioventricular valves are often abnormal, including a cleft in the anterior mitral leaflet [3]. MVP is found in 30%-35% of ASD patients with or without significant mitral regurgitation (MR)and seems to be secondary to an abnormal left ventricular geometry and dilatated right ventricle which leads to shortening of inter-papillary distance and redundant chordae tendineae [4]. Atrial fibrillation (AF) is the most common cause of hospital admission among all arrhythmias in general population and AF is also the most common arrhythmia in the athletic population [5].

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

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. 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. 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. A series of fourCHD 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. 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.

Analysis of risk factors and outcomes of acute kidney injury in young children after cardiac surgery

The aim of this study was to analysis of risk factors and outcomes of acute kidney injury (AKI) in young children with congenital heart disease (CHD) after cardiac surgery. The study included 137 young children with CHD after various types of cardiac surgery. The stages of AKI and indications for peritoneal dialysis (PD) were determined based of Kidney Disease: Improving Global Outcomes (KDIGO) guidelines. The incidence of AKI in young children in the general group was 40.9% (n=56). Stage 1 AKI was diagnosed in 21.9% (n=29) of patients, stage 2 AKI in 12.4% (n=17), and stage 3 AKI in 7.3% (n=10) of patients. Peritoneal dialysis was performed in 11.7% (n=16) of children. The incidence of AKI development after radical correct transposition of the great vessels (TGV) was 55.5% (n=5), truncus arteriosus (TA) was 100%, pulmonary atresia (PA)=25%, tetralogy of Fallot (TF)=38.1%, total anomalous pulmonary vein drainage (TAPVD)=60%, partial anomalous pulmonary vein drainage (PAPVD)=37.5%, atrioventricular canal (AVC)=44.4%, double outlet of main vessels from the right ventricle (DOMV from the RV)=60% , interventricular septal defect with high pulmonary hypertension (VSD)=21.6%, and combined operations was 46.6%. The need for PD after TGV correction was 22.2% (n=2), after TA=100%, after TF=33.3%, after TAPVD=20%, after AVC=11.1%, after VSD=1.9%, and after combined operations was 13.3%. Risk factors for AKI in young children were: younger age, initial heart failure, type of operation, prolonged cardiopulmonary bypass (CPB) and aortic clamping (AC), low cardiac output syndrome, inotropic and vasopressor therapy, hyperlactatemia. The development of AKI led to increased length of stay in the intensive care unit, overall hospitalization and infant mortality.

ERG potassium channels and T-type calcium channels contribute to the pacemaker and atrioventricular conduction in zebrafish larvae.

Bradyarrhythmias result from inhibition of automaticity, prolonged repolarization, or slow conduction in the heart. The ERG channels mediate the repolarizing current IKr in the cardiac action potential, whereas T-type calcium channels (TTCC) are involved in the sinoatrial pacemaker and atrioventricular conduction in mammals. Zebrafish have become a valuable research model for human cardiac electrophysiology and disease. Here, we investigate the contribution of ERG channels and TTCCs to the pacemaker and atrioventricular conduction in zebrafish larvae and determine the mechanisms causing atrioventricular block. Zebrafish larvae expressing ratiometric fluorescent Ca2+ biosensors in the heart were used to measure Ca2+ levels and rhythm in beating hearts invivo, concurrently with contraction and hemodynamics. The atrioventricular delay (the time between the start of atrial and ventricular Ca2+ transients) was used to measure impulse conduction velocity and distinguished between slow conduction and prolonged refractoriness as the cause of the conduction block. ERG blockers caused bradycardia and atrioventricular block by prolonging the refractory period in the atrioventricular canal and in working ventricular myocytes. In contrast, inhibition of TTCCs caused bradycardia and second-degree block (Mobitz type I) by slowing atrioventricular conduction. TTCC block did not affect ventricular contractility, despite being highly expressed in cardiomyocytes. Concomitant measurement of Ca2+ levels and ventricular size showed mechano-mechanical coupling: increased preload resulted in a stronger heart contraction invivo. ERG channels and TTCCs influence the heart rate and atrioventricular conduction in zebrafish larvae. The zebrafish lines expressing Ca2+ biosensors in the heart allow us to investigate physiological feedback mechanisms and complex arrhythmias.

Translational control of furina by an RNA regulon is important for left-right patterning, heart morphogenesis and cardiac valve function.

Heart development is a complex process that requires asymmetric positioning of the heart, cardiac growth and valve morphogenesis. The mechanisms controlling heart morphogenesis and valve formation are not fully understood. The pro-convertase FurinA functions in heart development across vertebrates. How FurinA activity is regulated during heart development is unknown. Through computational analysis of the zebrafish transcriptome, we identified an RNA motif in a variant FurinA transcript harbouring a long 3' untranslated region (3'UTR). The alternative 3'UTR furina isoform is expressed prior to organ positioning. Somatic deletions in the furina 3'UTR lead to embryonic left-right patterning defects. Reporter localisation and RNA-binding assays show that the furina 3'UTR forms complexes with the conserved RNA-binding translational repressor, Ybx1. Conditional ybx1 mutant embryos show premature and increased Furin reporter expression, abnormal cardiac morphogenesis and looping defects. Mutant ybx1 hearts have an expanded atrioventricular canal, abnormal sino-atrial valves and retrograde blood flow from the ventricle to the atrium. This is similar to observations in humans with heart valve regurgitation. Thus, the furina 3'UTR element/Ybx1 regulon is important for translational repression of FurinA and regulation of heart development.

Multi-chamber cardioids unravel human heart development and cardiac defects

The number one cause of human fetal death are defects in heart development. Because the human embryonic heart is inaccessible and the impacts of mutations, drugs, and environmental factors on the specialized functions of different heart compartments are not captured by invitro models, determining the underlying causes is difficult. Here, we established a human cardioid platform that recapitulates the development of all major embryonic heart compartments, including right and left ventricles, atria, outflow tract, and atrioventricular canal. By leveraging 2D and 3D differentiation, we efficiently generated progenitor subsets with distinct first, anterior, and posterior second heart field identities. This advance enabled the reproducible generation of cardioids with compartment-specific invivo-like gene expression profiles, morphologies, and functions. We used this platform to unravel the ontogeny of signal and contraction propagation between interacting heart chambers and dissect how mutations, teratogens, and drugs cause compartment-specific defects in the developing human heart.

Cardiac Laterality: Surgical Results of Right Atrial Isomerism.

Right atrial isomerism (RAI) is a complex entity with varying diagnostic and treatment outcomes due to its rarity. Treatment options range from palliative to corrective surgeries, resulting in heterogeneous outcomes. The aim of this study was to analyze the results obtained after cardiac surgery in patients with RAI. A retrospective study was conducted, including patients diagnosed with RAI who underwent cardiac surgery. Their follow-up was from 1 January 2010 to 31 March 2020. Demographic characteristics and perioperative conditions were described. Thirty-eight patients were included, the median age was 4 years (IQR 2-9.2) and 57.9% were men. The main diagnoses were atrioventricular canal (63.2%) and pulmonary stenosis (55.3%). The most common surgical procedures were modified Blalock-Taussig shunt (65.8%) and total cavopulmonary connection with an extracardiac conduit fenestrated without cardiopulmonary bypass (15.9%). We did not find any factors associated with negative outcomes in these patients. The overall survival was 86.8%, with a better outcome in those who did not require reintubation (log rank, p < 0.01). The survival of RAI was similar to other centers. Individuals with RAI should be evaluated rigorously to determine an adequate repair strategy, considering high morbidity and mortality.

Abstract 17273: Phenotypic Clustering of Patients With Heterotaxy Syndrome Predicts Outcomes of Mortality and Transplantation

Background: Current classifications of heterotaxy syndrome (HS) (e.g. left/right isomerism, polysplenia/asplenia) do not capture the heterogeneity of cardiac anomalies observed nor provide insight on risk stratification. We aimed to improve these classifications using cluster analysis to identify anatomic phenotypes in HS patients. Methods: Using a retrospective database of all HS patients seen at Boston Children’s Hospital from 1985-2014 (n=264), we performed principal component and cluster analyses on 47 cardiac anatomic variables and compared rates of mortality/transplantation across clusters. Results: Five clusters were identified ranging in size from 19 to 91 patients. Cluster #1 had a high prevalence of right-dominant complete atrioventricular canal defects (CAVC), double-outlet right ventricle (DORV), pulmonary stenosis/atresia (PS/PA), and total anomalous pulmonary venous connection (TAPVC); Cluster #2 of left-dominant CAVC, DORV, and TAPVC; Cluster #3 of left-sided obstructive lesions and interrupted IVC; Cluster #4 of transposition of the great arteries with PS/PA; and Cluster #5 of interrupted IVC with miscellaneous cardiac anomalies (Table). Over 80% of patients in clusters 1 and 2 underwent single ventricle palliation compared with only 16% of patients in cluster 5. Transplant-free survival was lowest in clusters 1, 2, and 3 but differed by single versus biventricular repair (Figure). Conclusions: Cluster analysis of cardiac anatomic variables identified 5 phenotypes of HS including 3 higher risk and 2 lower risk phenotypes. These findings highlight the need for improved phenotyping of HS to account for the high degree of disease heterogeneity.

Clinical utility of repeat fetal echocardiography in congenital heart disease.

To investigate the utility of repeat fetal echocardiography (FE) following a diagnosis of structural congenital heart disease (CHD) on the initial FE. We evaluated how often changes in management and counseling occurred based on subsequent FE findings and sought to determine which types of CHD were more likely to have changes in management and/or counseling based on repeat FE. This was a retrospective review of all patients who presented to our center between January 2012 and January 2019 and who had more than one FE performed for structural CHD. We reviewed consultation notes to determine whether management or counseling had changed based on FE findings at follow-up visits. Management variables included a change in location or mode of delivery, plan for atrial septostomy, initiation of prostaglandin infusion, umbilical line placement and planned admission location (nursery vs neonatal intensive care unit). We defined a counseling change as any of the above changes in management as well as any meaningful refinements in the cardiac diagnosis that led to a change in the overall prognosis or future management. Initial diagnoses were grouped into anatomically/hemodynamically relevant subgroups. Fisher's exact test was used to assess the relationship between the initial diagnosis and changes in management. Post-hoc pairwise comparisons were performed using Dunnett's test. Between January 2012 and January 2019, 267 patients underwent 534 follow-up FE assessments performed for structural CHD. Management change based on repeat FE occurred in 41/267 (15.4%) cases. A change in management was associated with the diagnosis made at the initial visit (P < 0.001). The proportion of cases with a management change was highest among those with an initial diagnosis of pulmonary valve abnormality/non-critical pulmonary stenosis (4/11 (36.4%)), followed by balanced atrioventricular canal (AVC) defect (5/17 (29.4%)) and left ventricular outflow tract obstruction/aortic valve abnormality or coarctation/interrupted aortic arch (19/68 (27.9%)). No management change occurred in fetuses diagnosed with isolated ventricular septal defect (VSD), truncus arteriosus, pulmonary vein anomaly or isolated arch sidedness/branching abnormality. Compared to those with a VSD, management was significantly more likely to be changed in fetuses with a balanced AVC defect (P = 0.025) and left heart lesions (P = 0.002). Right heart lesions showed a trend towards an increased incidence of management change (P = 0.05). A counseling change based on repeat FE occurred in 108/267 (40.4%) cases. The proportion of cases with a counseling change was highest among those with an initial diagnosis of pulmonary valve abnormality/non-critical pulmonary stenosis (8/11 (72.7%)) and hypoplastic left heart syndrome/critical aortic stenosis (5/9 (55.6%)). The clinical utility of follow-up FE is associated with the type of CHD diagnosed. Follow-up FE led to changes in management in several types of CHD, most commonly in cases with an initial diagnosis of right and left outflow obstructive lesions and balanced AVC defect. When developing programmatic protocols for the frequency of FE assessments, the type of CHD should be a major determinant, but additional studies are required to reach a consensus on how often serial FE should be performed for each type of CHD. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Anatomic considerations in the management of complete atrioventricular canal.

Patients with complete atrioventricular canal have a variable clinical course prior to repair. Many patients balance their circulations well prior to elective repair. Others manifest clinically significant pulmonary over circulation early in life and require either palliative pulmonary artery banding or complete repair. The objective of this study was to assess anatomic features that impact the clinical course of patients. In total, 222 patients underwent complete atrioventricular canal repair between 2012 and 2022 at a single institution. Twenty-seven (12%) patients underwent either pulmonary artery banding (n = 15) or complete repair (n = 12) at less than 3 months of age (Group 1). The remaining 195 (88%) underwent repair after 3 months of age (Group 2). Patient records and imaging were reviewed. The median post-operative length of stay following complete repair was 25 [7,46] days for those patients in Group 1 and 7 [5,12] days for those in Group 2 (p < 0.0001). There was relative hypoplasia of left-sided structures in Group 1 versus Group 2. Mean z-score for the ascending aorta was -1.2 (±0.8) versus -0.3 (±0.9) (p < 0.0001), the aortic isthmus was -2.1 (±0.8) versus -1.4 (±0.8) (p = 0.005). The pulmonary valve to aortic valve diameter ratio was median 1.47 [1.38,1.71] versus 1.38 [1.17,1.53] (p 0.008). Echocardiographic evaluation of the systemic and pulmonary outflow of patients with complete atrioventricular canal may assist in predicting the clinical course and need for early repair vs pulmonary artery banding.

Modeling of large-scale hoxbb cluster deletions in zebrafish uncovers a role for segmentation pathways in atrioventricular boundary specification.

Hox genes orchestrate the segmental specification of the muscular circulatory system in invertebrates but it has not proven straightforward to decipher segmental parallels in the vertebrate heart. Recently, patients with HOXB gene cluster deletion were found to exhibit abnormalities including atrioventricular canal defects. Using CRISPR, we established a mutant with the orthologous hoxbb cluster deletion in zebrafish. The mutant exhibited heart failure and atrioventricular regurgitation at 5days. Analyzing the four genes in the hoxbb cluster, isolated deletion of hoxb1b-/- recapitulated the cardiac abnormalities, supporting hoxb1b as the causal gene. Both in situ and in vitro data indicated that hoxb1b regulates gata5 to inhibit hand2 expression and ultimately is required to pattern the vertebrate atrioventricular boundary. Together, these data reveal a role for segmental specification in vertebrate cardiac development and highlight the utility of CRISPR techniques for efficiently exploring the function of large structural genomic lesions.

Echocardiographic Study of Ventricular Septal Defect in 1- to 12-Year-Old Children Visiting a Tertiary Care Center in Patna, India.

Background Symptoms of serious heart problems present at birthoften appear during the first few days, weeks, or months of a child's life. Shunt formation between the left and right ventricle is a crucial component of the pathophysiology of ventral septal defects. Objectives We aim to determine the most frequent types of ventricular septal defect (VSD) by echocardiography and whether there is any gender variation in the type of ventricular septal defect. Material and methods A total of 100 children who were clinically suspected of or diagnosed with VSD at the age of 1-12 years were enrolled in this study. The septum of the atrioventricular (AV) canal, the muscular septum, and the parietal band of the distal conal septum were evaluated by color Doppler. Ventricular septal defect (VSD) size and kind are similarly impacted by the 2D echo mode. The size and site of the VSD, associated congenital anomaly, and significant morphological changes in ventricular cavities, gender discrimination, and relation-specific types of ventricular septal defect were observed. Results A total of 100 VSD children presentedwith clinical symptoms of fast breathing, retraction of the chest, cough, cyanosis, fever, difficulty during feeding, cyanotic spell, chest pain, and edema at 65%, 62%, 54%, 52%, 54%, 29%, 9%, 11%, and 4%, respectively. Conclusion Early diagnosis is essential for effective medical care of diseases such as infective endocarditis (IE), which is present in some cases of VSD, and the avoidance of persistent pulmonary veno-occlusive disease (PVOD).

Contemporary outcomes for functional single ventricle with total anomalous pulmonary venous connection

ObjectiveIn 2004, we reported improved early survival for patients with functional single ventricle anatomy and total anomalous pulmonary venous connection. This study sought to discover if outcomes have been ameliorated in the contemporary era. MethodsThis was a single-center review of patients with single ventricle anatomy and total anomalous pulmonary venous connection who were admitted from 1984 to 2021. The cohort was divided into similarly sized groups by date of admission: Era 1: 1984 to 1992, Era 2: 1993 to 2007, and Era 3: 2008 to 2021. Survival was compared, and Cox proportional hazards models were used to evaluate the likelihood of mortality. ResultsWe included 190 patients with single ventricle anatomy and total anomalous pulmonary venous connection. Unbalanced atrioventricular canal defect (70%) was the most common primary diagnosis. The most common type of total anomalous pulmonary venous connection was supracardiac (49%). Approximately one-third (32%) of patients had pulmonary venous obstruction. There were no significant differences in patient characteristics across eras. Early survival after initial palliative operation improved between Eras 1 and 2, and then remained stable in Era 3. Overall survival improved from Era 1 to Eras 2 and 3 (P < .001), but not between Era 2 and 3. Survival to 10 years by Eras 1 to 3 was 15%, 51%, and 54%, respectively. The anatomic features associated with worse survival were hypoplastic left heart syndrome diagnosis (hazard ratio, 1.60; 1.04-2.57) and pulmonary venous obstruction (hazard ratio, 1.80; 1.24-2.69). ConclusionsOverall survival for patients with single ventricle anatomy and total anomalous pulmonary venous connection has plateaued since the early 2000s. Even in the most recent era, survival to age 10 years remains less than 60%. Risk factors for mortality include the diagnosis of hypoplastic left heart syndrome and pulmonary venous obstruction. Further studies should focus on identification of the pathophysiological factors underlying the increased mortality.

Congenital heart disease in Down's syndrome

Down syndrome is the most common chromosomal abnormality, it is associated with a wide variety of congenital heart defects, being considered as clinical elements of high infant morbidity and mortality. Objective. To describe the clinical outcomes of patients with Down syndrome undergoing surgery and interventionism as treatment for congenital heart disease at this Institution. 368 patients with Down syndrome and associated congenital heart disease were diagnosed. The variables studied were weight, stature, sex, age, type of heart disease, corrective procedure, length of stay in the hospital and intensive care unit, morbidity and mortality. 368 pediatric patients underwent surgical or interventional correction. Of which 197 (54%) were female, the median age was 24 months (interquartile range [IQR]: 14-48) in the surgical group and 36 months (IQR: 17-85) in the interventional group. The most frequent congenital heart diseases were: PCA (31%), IVC (28%), CAV (20%), ASD (16%) and tetralogy of Fallot with 4% respectively. Hospital stay was 9 days (IQR: 7-15) in the surgical group and 3 days (IQR: 2-5) in the hemodynamic group. Morbidities were postoperative infection in 30 patients (14%) and complete atrioventricular block in 19 patients (9%). Overall mortality including both surgical and interventional was 2%. The therapeutic, surgical and interventional results in children with Down syndrome and congenital heart disease have improved very satisfactorily. The lower prevalence of the atrioventricular canal in the Mexican population is noteworthy. It is essential to carry out a cardiological evaluation of children with Down syndrome and those with congenital heart disease to correct them in a timely manner to promote survival and quality of life.

Crk and Crkl Are Required in the Endocardial Lineage for Heart Valve Development.

Background Endocardial cells are a major progenitor population that gives rise to heart valves through endocardial cushion formation by endocardial to mesenchymal transformation and the subsequent endocardial cushion remodeling. Genetic variants that affect these developmental processes can lead to congenital heart valve defects. Crk and Crkl are ubiquitously expressed genes encoding cytoplasmic adaptors essential for cell signaling. This study aims to explore the specific role of Crk and Crkl in the endocardial lineage during heart valve development. Methods and Results We deleted Crk and Crkl specifically in the endocardial lineage. The resultant heart valve morphology was evaluated by histological analysis, and the underlying cellular and molecular mechanisms were investigated by immunostaining and quantitative reverse transcription polymerase chain reaction. We found that the targeted deletion of Crk and Crkl impeded the remodeling of endocardial cushions at the atrioventricular canal into the atrioventricular valves. We showed that apoptosis was temporally increased in the remodeling atrioventricular endocardial cushions, and this developmentally upregulated apoptosis was repressed by deletion of Crk and Crkl. Loss of Crk and Crkl also resulted in altered extracellular matrix production and organization in the remodeling atrioventricular endocardial cushions. These morphogenic defects were associated with altered expression of genes in BMP (bone morphogenetic protein), connective tissue growth factor, and WNT signaling pathways, and reduced extracellular signal-regulated kinase signaling activities. Conclusions Our findings support that Crk and Crkl have shared functions in the endocardial lineage that critically regulate atrioventricular valve development; together, they likely coordinate the morphogenic signals involved in the remodeling of the atrioventricular endocardial cushions.

Hey2 enhancer activity defines unipotent progenitors for left ventricular cardiomyocytes in juxta-cardiac field of early mouse embryo

The cardiac crescent is the first structure of the heart and contains progenitor cells of the first heart field, which primarily differentiate into left ventricular cardiomyocytes. The interface between the forming cardiac crescent and extraembryonic tissue is known as the juxta-cardiac field (JCF), and progenitor cells in this heart field contribute to the myocardium of the left ventricle and atrioventricular canal as well as the epicardium. However, it is unclear whether there are progenitor cells that differentiate specifically into left ventricular cardiomyocytes. We have previously demonstrated that an enhancer of the gene encoding the Hey2 bHLH transcriptional repressor is activated in the ventricular myocardium during mouse embryonic development. In this study, we aimed to investigate the characteristics of cardiomyocyte progenitor cells and their cell lineages by analyzing Hey2 enhancer activity at the earliest stages of heart formation. We found that the Hey2 enhancer initiated its activity prior to cardiomyocyte differentiation within the JCF. Hey2 enhancer-active cells were present rostrally to the Tbx5-expressing region at the early phase of cardiac crescent formation and differentiated exclusively into left ventricular cardiomyocytes in a lineage distinct from the Tbx5-positive lineage. By the late phase of cardiac crescent formation, Hey2 enhancer activity became significantly overlapped with Tbx5 expression in cells that contribute to the left ventricular myocardium. Our study reveals that a population of unipotent progenitor cells for left ventricular cardiomyocytes emerge in the JCF, providing further insight into the mode of cell type diversification during early cardiac development.

Effective and aesthetic results of horizontal right axillary minithoracotomy for congenital heart defects repair in children

Background: horizontal right axillary minithoracotomy is one of the treatment options for many simple congenital heart defects. This approach shows many aesthetic advantages besides effectiveness and safety. This study aims to: comment on the technical characteristics and early results of horizontal right axillary minithoracotomy in children at Hanoi Heart Hospital.&#x0D; Methods: a descriptive cross-sectional study. We retrospectively reviewed 156 patients who underwent horizontal right axillary minithoracotomy at Hanoi Heart Hospital from January 2022 to December 2022.&#x0D; Results: horizontal axillary approach could be applied even for children with low weight, average weight was 12.22 ± 8.67 kg, the lowest was 2.6 kg and the highest was 51.0 kg. A wide range of congenital heart defects were repaired, including ventricular septal defect closure (84 patients), secundum atrial septal defect closure (22 patients), ventricular septal defect with stenosis repair (31 patients), partial atrio-ventricular septal canal repair (6 patients), repair of atrial septal defect with partial abnormal return of the pulmonary veins (3 patients), repair of ventricular septal defect and atrial septal defect (4 patients), Cor triatriatum sinister repair (4 patients), mitral valve repair (1 patient), atrial septal defect and pulmonary valve stenosis repair (1 patient). Cannulation of the aorta and vena cavae was performed through the main incision, whose size ranged from 3.5 to 5.5cm. The average postoperative hospital stay was 7.34 ± 2.16 days, the rate of severe complications and hospital mortality were 0%.&#x0D; Conclusion: horizontal right axillary minithoracotomy was a good approach to correct many simple congenital heart defects in children. This technique is being applied at Hanoi Heart Hospital safely and provided outstanding advantages in terms of aesthetics.

Associated congenital heart disease with Hirschsprung's disease: a retrospective cohort study on 2,174 children.

To examine the incidence and phenotypes of congenital heart disease (CHD) in a large cohort of patients with Hirschsprung's disease (HSCR). Retrospective data review of children with HSCR between 2003 and 2020 was conducted at the Provincial Key Laboratory for Structural Birth Defects in Guangzhou, Guangdong, China. HSCR was confirmed by pathological diagnosis. CHD was defined as a gross structural abnormality of the heart or intrathoracic great vessels that is of functional significance. A total of 2,174 HSCR patients (84.7% males) were studied and 306 of them underwent echocardiography. Overall, 27 children (1.2%) had associated CHD. Among them, CHDs mostly presented as atrial and ventricular septal defects (n = 5 and 12 respectively) and patent ductus arteriosus (n = 4). Three patients (1.4‰) presented as a severe CHD including complete atrioventricular canal, congenitally corrected transposition of the great arteries and double-outlet of right ventricle. Among 14 patients carrying a chromosomal abnormality, CHD was detected in 4 infants (28.6%), all being mild forms of septal defects. Some new and severe types of CHD were found in patients with HSCR. Patients with syndromic features had higher incidence of CHD.

Discussion to: Left atrioventricular valve repair after primary atrioventricular canal surgery: Predictors of durability

Discussion to: Left atrioventricular valve repair after primary atrioventricular canal surgery: Predictors of durability

Laterality defect of the heart in non-teleost fish.

Dextrocardia is a rare congenital malformation in humans in which most of the heart mass is positioned in the right hemithorax rather than on the left. The heart itself may be normal and dextrocardia is sometimes diagnosed during non-related explorations. A few reports have documented atypical positions of the cardiac chambers in farmed teleost fish. Here, we report the casual finding of a left-right mirrored heart in an 85 cm long wild-caught spiny dogfish (Squalus acanthias) with several organ malformations. Macroscopic observations showed an outflow tract originating from the left side of the ventricular mass, rather than from the right. Internal inspection revealed the expected structures and a looped cavity. The inner curvature of the loop comprised a large trabeculation, the bulboventricular fold, as expected. The junction between the sinus venosus and the atrium appeared normal, only mirrored. MRI data acquired at 0.7 mm isotropic resolution and subsequent 3D-modeling revealed the atrioventricular canal was to the right of the bulboventricular fold, rather than on the left. Spurred by the finding of dextrocardia in the shark, we revisit our previously published material on farmed Adriatic sturgeon (Acipenser naccarii), a non-teleost bony fish. We found several alevins with inverted (left-loop) hearts, amounting to an approximate incidence of 1%-2%. Additionally, an adult sturgeon measuring 90 cm in length showed abnormal topology of the cardiac chambers, but normal position of the abdominal organs. In conclusion, left-right mirrored hearts, a setting that resembles human dextrocardia, can occur in both farmed and wild non-teleost fish.