Hemodynamic simulation of complete transposition of the great arteries for optimal treatment strategies based on its circulatory physiology.

Our study aimed to elucidate the role of different shunts and provide novel insights into optimal treatment approaches for complete transposition of the great arteries (TGA), which is characterized by unique and complicated circulatory dynamics. We constructed a computational cardiovascular TGA model and manipulated cardiovascular parameters, such as atrial septal defect (ASD) and patent ductus arteriosus (PDA) sizes, to quantify their effects on oxygenation and hemodynamics. In addition, ASD flow patterns were investigated as innovative indications for balloon atrial septostomy (BAS). Our model of TGA with an intact ventricular septum (TGA-IVS) showed that a large ASD can achieve sufficient mixing for survival without PDA, and the presence of PDA is detrimental to oxygen delivery. A treatment strategy for TGA-IVS that enlarges the ASD as much as possible by BAS and PDA closure would be desirable. In TGA with a ventricular septal defect (TGA-VSD), the VSD allows for higher oxygenation and reduces the detrimental effects of PDA on systemic circulation. In TGA-VSD, both strategies of enlarging the ASD by BAS with a closed PDA and adjusting the PDA in response to pulmonary vascular resistance (PVR) reduction without BAS may be effective. The simulated ASD flow patterns showed that the sharp peak left-to-right flow pattern in systole (σ-wave) reflected the hemodynamically significant ASD size, independent of PDA, VSD, and PVR. The ASD flow pattern visualized by Doppler echocardiography provides clinical insights into the significance of an ASD and indications for BAS, which are not readily apparent through morphological assessment.NEW & NOTEWORTHY Complete transposition of the great arteries (TGA) represents complex and unique circulation that is dependent on blood mixing through multiple interacting shunts. Consequently, the role of each shunt and the treatment strategy remain unclear. We developed a mathematical model of TGA circulation, revealing the significant influence of atrial septal defect (ASD) on oxygenation and hemodynamics. The blood flow pattern through the ASD reflects its hemodynamic impact and helps determine treatment strategies.

Complete free wall isolation of arrhythmogenic persistent left superior vena cava.

INTRODUCTION: Persistent left superior vena cava (PLSVC) is one of the major sources of triggers and drivers of atrial fibrillation (AF). There has been no established PLSVC ablation procedure to eliminate the arrhythmogenicity along the entire length of PLSVC. METHODS AND RESULTS: A 70-year-old woman with a history of two previous catheter ablations for AF, mitral valvuloplasty, and an unroofed coronary sinus-type atrial septal defect closure underwent the redo AF ablations. The AF trigger and driver were identified within the patient's enlarged PLSVC. The AF was treated by complete PLSVC free wall isolation. CONCLUSION: Complete PLSVC free wall isolation may be an effective ablation method to eliminate the arrhythmogenicity along the entire length of the PLSVC.

Trans-aortic mitral isthmus ablation after surgical patch closure for an atrial septal defect.

INTRODUCTION: In patients with prior atrial septal defect (ASD) closure and atrial tachyarrhythmias, transseptal puncture can be challenging. METHODS AND RESULTS: This case report discusses a 65-year-old man who had previously undergone pulmonary vein isolation (PVI) and cavo-tricuspid isthmus ablation for atrial fibrillation before ASD closure, respectively. He developed atrial tachycardia (AT) and underwent catheter ablation. AT was diagnosed as peri-mitral flutter and the mitral isthmus (MI) linear ablation via a trans-aortic approach successfully terminated it. CONCLUSION: This case demonstrates the feasibility and safety of transaortic MI linear ablation in patients with ASD closure devices or anatomical challenges when transseptal puncture is difficult.

The 2022 FASEB Virtual Catalyst Conference on the Cardiac Interatrial Septum and Stroke Risk, December 7, 2022.

There is emerging evidence that the cardiac interatrial septum has an important role as a thromboembolic source for ischemic strokes. There is little consensus on treatment of patients with different cardiac interatrial morphologies or pathologies who have had stroke. In this paper, we summarize the important background, diagnostic, and treatment considerations for this patient population as presented during the Federation of American Societies for Experimental Biology (FASEB) Virtual Catalytic Conference on the Cardiac Interatrial Septum and Stroke Risk, held on December 7, 2022. During this conference, many aspects of the cardiac interatrial septum were discussed. Among these were the embryogenesis of the interatrial septum and development of anatomic variants such as patent foramen ovale and left atrial septal pouch. Also addressed were various mechanisms of injury such as shunting physiologies and the consequences that can result from anatomic variants, as well as imaging considerations in echocardiography, computed tomography, and magnetic resonance imaging. Treatment options including anticoagulation and closure were addressed, as well as an in-depth discussion on whether the left atrial septal pouch is a stroke risk factor. These issues were discussed and debated by multiple experts from neurology, cardiology, and radiology.

PRKACA-related, atrial defects-polydactyly-multiple congenital malformation syndrome in an Indian patient.

PRKACA-related, atrial defects-polydactyly-multiple congenital malformation syndrome is a recently described skeletal ciliopathy, which is caused by disease-causing variants in PRKACA. The primary phenotypic description includes atrial septal defects, and limb anomalies including polydactyly and short limbs. To date, only four molecularly proven patients have been reported in the literature with a recurrent variant, c.409G>A p.Gly137Arg in PRKACA. In this study, we report the fifth affected individual with the same variant and review the clinical features and radiographic findings of this rare syndrome.

Right disc thrombosis of the new Gore Cardioform ASD Occluder.

BACKGROUND: The GCA is a well performing device in terms of efficacy despite complex anatomies (aortic rim <5 mm and ASD diameter >17 mm) with a good safety profile. AIMS: To evaluate atrial septal defect (ASD) features impacting on right disc device thrombosis in patients who underwent Gore Cardioform ASD Occluder (GCA) implantation. METHODS: A total of 44 consecutive patients undergoing percutaneous ASD with GCA device from January 2020 to September 2022 at our tertiary care Center were evaluated. The minimum follow-up was 6 months. RESULTS: The patients were stratified in two groups according to a cut-off value of ASD diameter equal to 20 mm at sizing balloon, derived from ROC analysis (AUC = 0.894; p = 0.024). Baseline characteristics were comparable between groups in terms of age, sex, weight, height, and interatrial septum dimensions. Patients with ASD > 20 mm (n = 9) had a higher ASD/device dimension ratio, both at echocardiography (p = 0.009) and at sizing balloon (p = 0.001), longer fluoroscopic time (p = 0.022), and higher incidence of device thrombosis (0.006). Right disc thrombosis was observed in three patients of the ASD > 20 mm group, always in the inferior portion of the right disc. On univariate analysis, ASD diameter at sizing balloon (OR 1.360; p = 0.036) was the only positive predictor of device thrombosis. CONCLUSIONS: Right disc thrombosis of the GCA device may be under-recognized at follow-up, hence deserving clinical attention, especially in those patients with larger ASD diameters.

Endoleak in covered CP stent causes procedural failure during transcatheter closure of sinus venosus defects.

Transcatheter sinus venosus defect closure uses a long covered stent of appropriate length and diameter across the cavoatrial junction after balloon interrogation. The fabric in the covered stent creates a roof for the right upper pulmonary vein that closes the interatrial communication and redirects the vein into the left atrium behind the stent. A fabric tear in the covered stent may cause endoleak that will result in residual flows across the struts of the covered stent, causing procedural failure. This report highlights the identification of fabric leak by angiography and transesophageal echocardiography and steps to overcome this complication by the placement of another overlapping covered stent.

Echocardiography-guided percutaneous closure of oval-shaped secundum atrial septal defects.

BACKGROUND: An atrial septal defect (ASD) is considered oval-shaped when its shortest diameter is less than 75% of the longest diameter. Research on percutaneous closure of oval-shaped ASDs is limited, with no known reports of non-fluoroscopic closure for this population. OBJECTIVE: To assess the effectiveness of non-fluoroscopic percutaneous closure for oval-shaped ASDs. METHODS: This single-center retrospective study evaluates patients undergoing non-fluoroscopic percutaneous closure of oval-shaped ASDs, defined by the shortest to longest diameter ratio < 0.75, a circular index of 1.33, or ultrasound visualization of an oval shape. Device size was chosen to be 0-4 mm larger than the defect's longest diameter, based on transthoracic and transesophageal ultrasound measurements. RESULTS: We identified 78 patients (33.3% children, 20.5% males) with a mean age of 27.4 ± 16.3 years and a mean weight of 46.8 ± 19.8 kg. The mean longest diameter and mean shortest diameter of ASDs were 23.3 ± 6.8 mm and 15.8 ± 5 mm, respectively. The mean ratio of the shortest to longest diameter was 0.7 ± 0.1. Percutaneous closure was not attempted in 7/78 (9%) patients. Three out of 71 (4.2%) procedures were fluoroscopy-guided upfront due to technical difficulties, and 5/71 (7%) were converted to fluoroscopy-guided closure. Overall procedural success rate was 98.6% (70/71) including 63/71 (88.7%) performed with zero fluoroscopy. Mean device size was 26.5 ± 7.1 mm. Mean procedural time was 45.3 ± 22.6 min. Eleven intraprocedural complications occurred including 6 arrhythmias, 3 pericardial effusions, and 2 device dislodgements. CONCLUSION: Transcatheter closure of oval-shaped ASD is safe and feasible. Echocardiography is adequate for adequate operative guidance.

The association of right ventricular-pulmonary arterial coupling and pulmonary vascular resistance in adult patients with uncorrected atrial septal defect.

BACKGROUND: Atrial septal defects (ASD) are the most common type of adult congenital heart disease (ACHD) associated with a high risk developing of pulmonary arterial hypertension (PAH). ASD closure is not recommended in patients with PAH and Pulmonary Vascular Resistance (PVR) ≥ 5 Wood Unit (WU). Noninvasive methods have been proposed to measure PVR; however, their accuracy remains low. Right Ventricle (RV) - Pulmonary Artery (PA) coupling is defined as the ability of the RV to adapt to high-resistance conditions. Tricuspid Annular Plane Systolic Excursion (TAPSE)/estimated pulmonary artery systolic pressure (ePASP) calculation using echocardiography is a noninvasive technique that has been proposed as a surrogate equation to evaluate RV-PA coupling. Currently, no research has demonstrated a relationship between RV-PA coupling and PVR in patients with ASD. METHODS: The study participants were consecutive eligible patients with ASD who underwent right heart catheterization (RHC) and echocardiography at Hasan Sadikin General Hospital, Bandung. Both the procedures were performed on the same day. RV-PA Coupling, defined as TAPSE/ePASP > 0.31, was assessed using echocardiography. The PVR was calculated during RHC using the indirect Fick method. RESULTS: There were 58 patients with ASD underwent RHC and echocardiography. Among them, 18 had RV/PA Coupling and 40 had RV/PA Uncoupling. The PVR values were significantly different between the two groups (p = 0.000). Correlation test between TAPSE/ePASP with PVR showed moderate negative correlation (r= -0.502, p = 0.001). TAPSE/ePASP ≤ 0.34 is the cutoff point to predict PVR > 5 WU with sensitivity of 91.7% and specificity 63.6%. CONCLUSION: This study showed a moderate negative correlation between TAPSE/ePASP and PVR. TAPSE/ePASP ≤ 0.34 could predict PVR > 5 WU with good sensitivity.

Double trouble - dual outflow tract obstruction in congenital heart disease: a case report.

BACKGROUND: Double chambered right ventricle is a rare congenital heart disease that is characterised by the presence of an anomalous muscle bundle that divides the right ventricle into a low pressure superior (distal) chamber and a high pressure inferior (proximal) chamber. It is found in association with a ventricular septal defect in 90% cases with other associations being tetralogy of Fallot, transposition of great vessels, atrial septal defect and Ebstein's anomaly. On the other hand, subaortic membrane is a form of discrete subaortic stenosis that is characterised by a membranous diaphragm in the subvalvular location of the left ventricular outflow tract. Both of these entities are responsible for causing subvalvular outflow tract obstruction. The occurrence of double chambered right ventricle in association with subaortic membrane is an extremely rare entity with only a few case reports available in the literature. CASE REPORT: A 13-year-old male child with history of chest pain and palpitations presented to the outpatient department of a tertiary care center. Transthoracic echocardiography revealed a subaortic membrane producing a pressure gradient across the left ventricular outflow tract with dilatation of the right atrium and right ventricle which could not be fully evaluated on echocardiography. Cardiac computed tomography was then performed which additionally revealed an anomalous muscle bundle coursing across the right ventricle from the septum to the subinfundibular region creating a double chambered right ventricle. The patient was then taken up for reconstruction of right ventricular outflow tract and resection of subaortic membrane. CONCLUSION: Right and left outflow tract obstructions are rare congenital lesions which when seen in combination, become even more infrequent. Echocardiography is a robust tool that detects turbulent flow to identify such lesions. However, poor acoustic window may sometimes result in missing these lesions and computed tomography in such situations can play an important role in detection as well as complete preoperative imaging evaluation.

Clinical diversity and molecular mechanism of VPS35L-associated Ritscher-Schinzel syndrome.

PURPOSE: The Retriever subunit VPS35L is the third responsible gene for Ritscher-Schinzel syndrome (RSS) after WASHC5 and CCDC22. To date, only one pair of siblings have been reported and their condition was significantly more severe than typical RSS. This study aimed to understand the clinical spectrum and underlying molecular mechanism in VPS35L-associated RSS. METHODS: We report three new patients with biallelic VPS35L variants. Biochemical and cellular analyses were performed to elucidate disease aetiology. RESULTS: In addition to typical features of RSS, we confirmed hypercholesterolaemia, hypogammaglobulinaemia and intestinal lymphangiectasia as novel complications of VPS35L-associated RSS. The latter two complications as well as proteinuria have not been reported in patients with CCDC22 and WASHC5 variants. One patient showed a severe phenotype and the other two were milder. Cells established from patients with the milder phenotypes showed relatively higher VPS35L protein expression. Cellular analysis found VPS35L ablation decreased the cell surface level of lipoprotein receptor-related protein 1 and low-density lipoprotein receptor, resulting in reduced low-density lipoprotein cellular uptake. CONCLUSION: VPS35L-associated RSS is a distinct clinical entity with diverse phenotype and severity, with a possible molecular mechanism of hypercholesterolaemia. These findings provide new insight into the essential and distinctive role of Retriever in human development.

Differential diagnosis of congenital ventricular septal defect and atrial septal defect in children using deep learning-based analysis of chest radiographs.

BACKGROUND: Children with atrial septal defect (ASD) and ventricular septal defect (VSD) are frequently examined for respiratory symptoms, even when the underlying disease is not found. Chest radiographs often serve as the primary imaging modality. It is crucial to differentiate between ASD and VSD due to their distinct treatment. PURPOSE: To assess whether deep learning analysis of chest radiographs can more effectively differentiate between ASD and VSD in children. METHODS: In this retrospective study, chest radiographs and corresponding radiology reports from 1,194 patients were analyzed. The cases were categorized into a training set and a validation set, comprising 480 cases of ASD and 480 cases of VSD, and a test set with 115 cases of ASD and 119 cases of VSD. Four deep learning network models-ResNet-CBAM, InceptionV3, EfficientNet, and ViT-were developed for training, and a fivefold cross-validation method was employed to optimize the models. Receiver operating characteristic (ROC) curve analyses were conducted to assess the performance of each model. The most effective algorithm was compared with the interpretations provided by two radiologists on 234 images from the test group. RESULTS: The average accuracy, sensitivity, and specificity of the four deep learning models in the differential diagnosis of VSD and ASD were higher than 70%. The AUC values of ResNet-CBAM, IncepetionV3, EfficientNet, and ViT were 0.87, 0.91, 0.90, and 0.66, respectively. Statistical analysis showed that the differential diagnosis efficiency of InceptionV3 was the highest, reaching 87% classification accuracy. The accuracy of InceptionV3 in the differential diagnosis of VSD and ASD was higher than that of the radiologists. CONCLUSIONS: Deep learning methods such as IncepetionV3 based on chest radiographs in the study showed good performance for differential diagnosis of congenital VSD and ASD, which may be able to assist radiologists in diagnosis, education, and training, and reduce missed diagnosis and misdiagnosis.

A rare case of inferior sinus venosus atrial septal defect and concomitant hypoplasia of the posterior mitral valve leaflet.

Inferior sinus venosus atrial septal defect (SVASD) is the rarest form of the atrial septal defect (ASD) and can sometimes go unnoticed. Although this defect can be associated with other congenital anomalies, its association with hypoplasia of the posterior mitral leaflet is extremely rare. In this case, we present a woman with a history of surgery for an ostium secundum ASD who exhibited persistent right heart chamber dilation. Echocardiography revealed hypoplasia of the posterior mitral leaflet, and cardiac magnetic resonance (CMR) imaging confirmed the presence of a previously undetected inferior sinus venosus ASD.

A comparison of intracardiac echocardiography and transesophageal echocardiography for guiding device closure of ostium secundum atrial septal defect: A 15-year experience.

BACKGROUND AND AIM: Our aim was to evaluate the fluoroscopy time (FT), procedure time (PT) safety and efficacy when using intracardiac echocardiography (ICE) in comparison to transesophageal echocardiography (TEE) guidance for transcatheter closure of Ostium Secundum Atrial Septal Defect (OS-ASD). METHOD: Ninety patients (n = 90) diagnosed with OS-ASD underwent transcatheter closure between March 2006 and October 2021. Fifty-seven patients were treated under ICE guidance, while 33 patients were treated under TEE guidance. RESULTS: Mean age was 43 ± 15 years and 42 ± 10 years in the ICE and TEE groups, respectively. The majority of patients had a centrally placed defect. Median FT was 8.40 min versus 11.70 min (p < .001) in the ICE group compared to the TEE group, respectively. Median PT was 43 min versus 94 min (p < .001) in the ICE group compared to the TEE group, respectively. Both ICE and TEE provided high quality images. All interventions were completed successfully, except for one patient in the ICE group who experienced a device migration, the development of atrial tachycardia in one patient and atrial fibrillation in two patients in the ICE group which spontaneously cardioverted. There were no other complications. CONCLUSION: This study on a consistent cohort of patients with OS-ASD undergoing percutaneous closure suggests that use of ICE is safe and efficacious. Compared to TEE, ICE demonstrated significantly shorter FT and PT, decreasing the entire duration of the procedure and x-ray exposure. No relevant differences were observed in terms of success rate and complications.

Efficacy and Safety of Transthoracic Versus Transesophageal Echocardiography for Monitoring Closure of Atrial or Ventricular Septal Defects: A Systematic Review and Meta-Analysis.

PURPOSE: For the repair of atrial/ventricular septal defects (ASD/VSD), transthoracic echocardiography (TTE) is easy to perform, cost-effective, and does not require general anesthesia and intubation. Still, TTE is not universally accepted. To compare efficacy and safety of TTE versus transesophageal echocardiography (TEE) to guide percutaneous ASD/VSD closure. METHODS: PubMed, Embase, and the Cochrane library were searched for articles published from their inception to December 2023. The primary outcome was the procedural success rate. The secondary outcomes were residual shunt, late complications, procedure time, and fluoroscopy time. All meta-analyses were performed using a random-effects model. RESULTS: Eight studies and 1295 patients were included. There were no significant differences between TTE and TEE regarding the procedural success rate (OR = 1.93, 95% CI: 0.90-4.13, p = 0.092; I2 = 52.2%, Pheterogeneity = 0.063) and residual shunt rate (OR = 0.81, 95% CI: 0.38-1.76, p = 0.600; I2 = 0%, Pheterogeneity = 0.518). Compared with TEE, TTE reduced the frequency of late complications (OR = 0.25, 95% CI: 0.14-0.43, p < 0.001; I2 = 13.8%, Pheterogeneity = 0.326), reduced the procedure time (WMD = -8.92, 95% CI: -12.08, -5.75, p < 0.001; I2 = 87.4%, Pheterogeneity < 0.001), and reduced the fluoroscopy time (WMD = -5.08, 95% CI: -9.59, -0.56, p = 0.028; I2 = 95.6%, Pheterogeneity < 0.001). The sensitivity analyses showed that the results of the meta-analyses were robust. CONCLUSION: Compared with TEE, TTE showed no differences regarding the rates of success and residual shunt, but there were lower rates of late complications and shorter procedure and fluoroscopy times.

Three-dimensional transesophageal echocardiography measurements of ASD sizing parameters in comparison to balloon sizing method in percutaneous ASD closure.

BACKGROUND: Balloon sizing (BS) has been used for device size selection in percutaneous atrial septal defect (ASD) closure. Due to its limitations, alternative imaging techniques like three-dimensional transesophageal echocardiography (3D-TEE) are valuable for guiding ASD device size selection during ASD closure procedures. The purpose of this study was to compare ASD sizing using measurements obtained from 3D-TEE to those utilizing the standard balloon sizing method. METHODS: We identified 53 patients with single secundum type ASD without PFO who underwent percutaneous closure at the Tehran Heart Center between 2019 and 2022. Balloon sizing was performed in all patients with the stop-flow technique, and the choice of device size was determined based on the sizing derived from BS. 3D-TEE imaging was performed before the intervention, and the ASD shape and quality of ASD rims were assessed. RESULTS: Among the 53 patients who underwent single ASD device closure, multiple 3D TEE measurements significantly correlated with balloon sizing results. This included defect area, perimeter, and diameter obtained from 3D-TEE images multi-planar reconstruction. ASD perimeter detected by 3D TEE had the best correlation with BS results. When divided by the shape of ASD, there was no significant difference between our 3D-images data and BS in round or oval-shaped ASDs. CONCLUSION: The 3D-TEE study is reliable for assessing ASD configurational characteristics in percutaneous device closure candidates. 3D-TEE has the potential to accurately determine the appropriate device size and reduce complications, costs, and procedural duration. Further research is needed to validate these findings and establish the role of 3D-TEE measurements in guiding the best treatment decisions for ASD closure.

Delayed diagnosis of Loeys-Dietz syndrome revealed through atrial septal defect with pulmonary artery dilation.

Loeys-Dietz syndrome (LDS) is an autosomal-dominant connective tissue disorder associated with mutations in the transforming growth factor ß receptor. It is characterized by distinctive craniofacial changes, skeletal features, and cardiovascular complications. We present a case of a 24-year-old male with development delay and a one-year history of progressively worsening dyspnea on moderate exertion and orthopnea. Echocardiography revealed right atrial and right ventricle dilation, right ventricle hypertrophy, atrial septal defect, and aneurysmal dilation of the pulmonary artery trunk. This case underscores the importance of early detection and comprehensive imaging in patients suspected of having LDS, particularly considering the potential for atypical vascular manifestations.

Modeling of multiple atrial septal defects with inferior vena cava rim deficiency: Three-dimensional visualization of the rim based on transthoracic echocardiographic imaging.

The morphologic features of the multiple atrial septal defects assessed by TTE-based 3D imaging were similar to those by 3D-TEE. TTE-based 3D model had excellent visibility, allowing observation of 3D structure of the rims of the defects. It may be useful method for assessment of the multiple atrial septal defects.

Quantitative evaluation of right ventricular myocardial function changes in patients with atrial septal defect before and after occlusion by noninvasive right ventricular pressure-strain loop.

OBJECTIVE: The noninvasive right ventricular pressure-strain loop (PSL) represents a novel method for the quantitative assessment of right ventricular myocardial function. Given that atrial septal defect (ASD) is a prevalent congenital heart anomaly associated with right ventricular volume overload, this study aimed to quantitatively assess the myocardial function of the right ventricle in ASD patients pre- and post-occlusion by noninvasive right ventricular PSL. METHODS: This study included 36 patients diagnosed with secundum ASD group and 30 healthy adults (control group). We compared conventional right ventricular echocardiographic parameters, right ventricular strain, and myocardial work in the ASD group before occlusion, two days post-occlusion, and three months post-occlusion, with those in the control group. RESULTS: Prior to and two days following occlusion, the ASD group exhibited higher right ventricular global work index (RVGWI), right ventricular global wasted work (RVGWW), and right ventricular global constructive work (RVGCW) compared to the control group (P < .05). Within the ASD group, post-occlusion, RVGWI, RVGCW, and RVGWW values were significantly reduced compared to pre-occlusion values (P < .001). Furthermore, RVGWI and RVGCW showed a significant decrease three months after occlusion compared to two days post-occlusion (P < .05). Multivariate regression analysis identified ASD diameter and pulmonary artery systolic pressure (PASP) as independent predictors of RVGWI (ß = .405, P < .001; ß = 2.307, P = .037) and RVGCW(ß = .350, P<.001; ß = 1.967, P = .023). CONCLUSIONS: The noninvasive right ventricular PSL effectively demonstrates the alterations in right ventricular myocardial function in ASD patients, pre- and post-occlusion. The metrics of right ventricular myocardial work (RVMW) offer a novel indicator for evaluating right ventricular myocardial function in these patients. Moreover, ASD diameter and PASP emerge as independent determinants of RVGWI and RVGCW.

Clinical Presentation and Therapy of Atrial Septal Defect.

Atrial septal defects (ASDs) occur in 1 of 1500 live births and constitute 6-10% of congenital heart defects. There is a female-to-male predominance of 2 to 1. According to their embryological origins, we can differentiate five different types of ASDs (see Fig. 23.1).