Discordant Ventriculoarterial Connections Research Articles

How best can we name the channels seen in the setting of deficient ventricular septation?

Surgical repair of channels between the ventricles is enhanced when the surgeon knows precisely where to place a patch, or baffle, so as to restore septal integrity. The paediatric cardiologist should provide the necessary information. Communication will be enhanced if the same words are used to account for the structures in question. Currently, however, the same term, namely "ventricular septal defect," is used to account for markedly different areas within the heart. Closure of perimembranous defects found in hearts with concordant or discordant ventriculo-arterial connections restores the integrity of the ventricular septum, at the same time separating the systemic and pulmonary blood streams. When both arterial trunks arise from the right ventricle, in contrast, the surgeon when placing a baffle so as to separate the blood streams, does not close the channel most frequently described as the "ventricular septal defect." In this review, we show that the perimembranous lesions as found in hearts with concordant or discordant ventriculo-arterial connections are the right ventricular entrances to the areas subtended beneath the hinges of the leaflets of the aortic or pulmonary valves. When both arterial trunks arise from the right ventricle, and the channel between the ventricles is directly subaortic, then the channel termed the "ventricular septal defect" is the left ventricular entrance to the comparable space subtended beneath the aortic root. We argue that recognition of these fundamental anatomical differences enhances the appreciation of the underlying morphology of the various lesions that reflect transfer, during cardiac development, of the aortic root from the morphologically right to the morphologically left ventricle.

Optimizing Surgical Selection for Transposition With Left Ventricular Outflow Tract Obstruction

BackgroundStudies that have assessed the Rastelli and Nikaidoh operations for transposition of the great arteries (TGA) with obstructed left ventricular outflow tract obstruction (LVOTO) have not fully evaluated the anatomic drivers that may contribute to surgical selection. We present our procedural selection process for optimizing outcomes of complex TGA in the modern era. MethodsThis is a single-center, retrospective study that included pediatric patients who underwent either a Nikaidoh or Rastelli operation for the treatment of TGA-LVOTO, congenitally corrected TGA–LVOTO, or double-outlet right ventricle TGA type–LVOTO from June 2004 to June 2021. ResultsThere were 34 patients stratified by Nikaidoh (n = 16) or Rastelli (n = 18) operation. The incidence of all postoperative complications and mortality was low, and the incidence of complications between the groups was similar. Patients were more likely to have undergone a Nikaidoh than a Rastelli if they had a pulmonary annulus >5 mm (87.5% vs 11.1%), anteriorly/posteriorly oriented great vessels (88% vs 8%), remote (80% vs 11%) or restrictive (75% vs 6%) ventricular septal defect, and right ventricular hypoplasia (50% vs 0%; all, P < .05). The resulting rates of reoperation were similar between the groups (44.0% vs 37.5%; P = .24) and largely composed of conduit replacements in the Rastelli patients and valvular repairs or replacements in the Nikaidoh group. Rates of catheter-based interventions were also similar. ConclusionsThese findings suggest that for the optimal treatment of conotruncal anomalies with discordant ventriculoarterial connections, procedural selection should be based on pathoanatomic criteria that can ensure patients undergo the operation most suited to their anatomy.

Единственный желудочек сердца у кота породы мейн-кун

Univentricular heart (UH) is a rare group of congenital heart disease characterized by the atrial chambers connects with one ventricular chamber. The most frequent UH is double inlet morphologically left ventricle with the discordant ventriculo-arterial connection. The main diagnostic methods are echocardiography, angiocardiography and magnetic resonance imaging. In humans, heart transplantation is a radical method of surgical treatment. Palliative surgical management is different based on the underlying anatomy and include 2 or 3 stage defect correction with the exclusion of the rudimentary ventricle from the circulation. The focus of therapy is to management heart failure and pulmonary hypertension. The article describes the stages of diagnosis and treatment of UH in a Maine Coon.

Imaging characteristics and associations of left atrioventricular valve atresia and patent aortic root with lateralized atrial chambers on multidetector CT.

To study the imaging characteristics and the associations of left atrioventricular valve atresia with patent aortic root and lateralized atrial chambers on multidetector computed tomography (CT) angiography. We retrospectively evaluated all the CT angiography studies performed for the evaluation of various congenital heart diseases at our center from January 2014 to December 2021. Cases with left atrioventricular valve atresia and patent aortic root with lateralized atrial chambers were identified. The types of cardiovascular involvement as identifiable on CT angiography were studied and compiled. A total of 38 patients with left atrioventricular valve atresia and patent aortic root were included (median age: 5 months, males: 31). A total of 89.5% had usual atrial arrangement and 10.5% had mirror imagery of atria. Normal drainage of right and left superior caval veins and inferior caval vein into systemic venous atrium was seen in 77.8%, 61.5%, and 86.6%, respectively. Anomalous pulmonary venous drainage was seen in 3 (7.9%) patients. Atrial and ventricular septal defects were the most common associations. Imperforate left atrioventricular membrane was seen in 9 (23.7%) patients and absent left atrioventricular connection in 27 (71.1%). Discordant right atrioventricular connection was seen in 5 (13.1%) patients. While a double outlet right ventricle (76.3%) was the most common ventriculoarterial connection, discordant ventriculo-arterial connection (transposition) in 4 (10.5%). Most patients had good sized pulmonary arteries. Patent arterial duct and right aortic arch were seen in 29% and 21%, respectively. Aberrant right subclavian artery was the most common arch vessel anomaly. Coronary anomalies were seen in 7 patients (19%); single coronary artery being the most common. Majority of the patients with left atrioventricular valve atresia and patent aortic root with lateralized atrial chambers have usual atrial arrangement, normal right atrioventricular connections and a double outlet configuration of the right ventricle. Absent left atrioventricular connection is a more common than imperforate left atrioventricular valve membrane. Atrial and ventricular septal defects are the most common associations. Comprehensive CT based evaluation of vascular and nonvascular thoracic structures is imperative before surgery or interventions in patients with mitral atresia.

Deep Phenotypic Analysis for Transposition of the Great Arteries and Prognosis Implication

BackgroundTransposition of the great arteries (TGA) consists of about 3% of all congenital heart diseases and 20% of cyanotic congenital heart diseases. It is always accompanied by a series of other cardiac malformations that affect the surgical intervention strategy as well as prognosis. In this study, we comprehensively analyzed the phenotypes of the patients who had TGA with concordant atrioventricular and discordant ventriculoarterial connections and explored their association with prognosis.Methods and ResultsWe retrospectively reviewed 666 patients with a diagnosis of TGA with concordant atrioventricular and discordant ventriculoarterial connections in Fuwai Hospital from 1997 to 2019. Under the guidance of the Human Phenotype Ontology database, patients were classified into 3 clusters. The Kaplan‐Meier method was used to analyze the prognosis, and the Cox proportional regression model was used to investigate the risk factors. In this 666‐patient TGA cohort, the overall 5‐year survival rate was 94.70% (92.95%–96.49%). Three clusters with distinct phenotypes were obtained by the Human Phenotype Ontology database. Kaplan‐Meier analysis revealed a significant difference in freedom from reintervention among 3 clusters (P<0.001). To eliminate the effect of surgeries, we analyzed patients who only received an arterial switch operation and still found a significant difference in reintervention (P=0.019).ConclusionsWe delineated a big cardiovascular phenotypic profile of an unprecedentedly large TGA cohort and successfully risk stratified them to reveal prognostic significance. Also, we reported the outcomes of a large TGA population in China.

Is Transposition of the Great Arteries Associated With Shortening of the Intrapericardial Portions of the Great Arterial Trunks? An Echocardiographic Analysis on Newborn Infants With Simple Transposition of the Great Arteries to Explore an Animal Model-Based Hypothesis on Human Beings.

BackgroundThe pathogenesis of transposition of the great arteries (TGA) as a congenital heart defect of the outflow tract with discordant ventriculoarterial connections remains an enigma. TGA usually have parallel great arteries suggesting that deficient torsion of the embryonic arterial heart pole might cause discordant ventriculoarterial connections. It has been speculated that deficient elongation of the embryonic outflow tract might prevent its normal torsion resulting in TGA. The aim of our study was to clarify whether the intrapericardial portions of the great arteries in human patients with TGA might be indeed shorter than in normal hearts.Methods and ResultsThirty‐four newborns with simple TGA and 35 newborns with normal hearts were analyzed by using images of the outflow tract in their echocardiograms and the following defined lengths of the great arteries were measured: aortic length 1, (AoL‐1) and aortic length 2 (AoL‐2) = distance between left and right aortic valve level and origin of the brachiocephalic artery, respectively. Pulmonary trunk length 1 (PTL‐1) and pulmonary trunk length 2 (PTL 2) = distance between left and right pulmonary valve level and origin of left and right pulmonary artery, respectively. All measurements of the AoL were significantly shorter in TGA compared to normal hearts (AoL‐1: 1.6±0.2 versus 2.05±0.1; P<0.0001; AoL‐2: 1.55±0.2 versus 2.13±0.1; P<0.0001). With regard to the pulmonary trunk (PT), PTL‐1 and PTL‐2 were found to be shorter and longer, respectively, in TGA compared with normal hearts, reflecting the differences in the spatial arrangement of the PT between the 2 groups as in TGA the PT is showing a mirror image of the normal anatomy. However, the overall length of the PT between the 2 groups did not differ.ConclusionsOur data demonstrate that, compared with normal newborns, the ascending aorta is significantly shorter in newborns with TGA whereas the overall length of the PT does not differ between the 2 groups. This finding is in accord with the animal model‐based hypothesis that TGA may result from a growth deficit at the arterial pole of the embryonic heart.

Femoral Artery–Systemic-Pulmonary Shunt–Femoral Vein Wire Loop to Assist Balloon Pulmonary Valvuloplasty in Infants with Discordant Atrioventricular and Ventriculoarterial Connection, Ventricular Septal Defect, and Extremely Severe Pulmonary Stenosis

Femoral Artery–Systemic-Pulmonary Shunt–Femoral Vein Wire Loop to Assist Balloon Pulmonary Valvuloplasty in Infants with Discordant Atrioventricular and Ventriculoarterial Connection, Ventricular Septal Defect, and Extremely Severe Pulmonary Stenosis

Surgical Options for Transposition of the Great Arteries With Ventricular Septal Defect and Left Ventricular Outflow Tract Obstruction: Evolution and Functional Impact

Surgery for D-transposition of the great arteries, ventricular septal defect and left ventricular outflow tract obstruction has continuously evolved to achieve optimal hemodynamic performance across the right and left ventricular outflow tracts, include predominantly native tissues, and preserve pulmonary valve function. Classically, three types of repair are applied: Rastelli, REV, and translocation procedures. The concept of translocation remains more radical and exposed to many modifications. Its extensive reconstructive nature extends its application to similar lesions with discordant ventriculo-arterial connection. We tried to compare the values and limitations of these surgical options, emphasizing how a more anatomical repair could impact the functional outcome.

Defining transposition: What have we learnt?

Understanding transposition is important for all who hope to effectively treat patients with the condition. The variants of the condition are frequently debated in the literature. We describe an unusual variant of transposition, in which despite the arterial roots being supported by morphologically inappropriate ventricles, the roots themselves were normally related, with the intrapericardial arterial trunks spiraling as they extended into the mediastinum. The specimen was identified following the re-categorization of our archive, and we subsequently conducted a detailed analysis of the underlying morphology. Using the principles of sequential segmental analysis, we compared the morphology with standard examples previously described. We show how it was the recognition of such hearts that promoted that concept that the combination of connections across the atrioventricular and ventriculo-arterial junctions was the essence of transposition. In the most common variant, the arrangements are concordant at the atrioventricular junctions, but discordant at the ventriculo-arterial junctions. We suggest that the overall arrangement of discordant ventriculo-arterial connections is best described simply as “transposition.” When the discordant ventriculo-arterial connections are combined with similarly discordant connections at the atrioventricular junctions, the transposition is congenitally corrected. We point out that the use of “d” and “l” as prefixes does not distinguish between transposition and its congenitally corrected variant. For those using segmental notations, the correct description for the rare variant found in the setting of a posteriorly located aortic root with the usual atrial arrangement is transposition (S, D, NR).

Bentall procedure for the repair of a neoaortic aneurysm after the Norwood procedure in a patient with tricuspid atresia and a discordant ventriculo-arterial connection

Neoaortic root dilation is a common phenomenon after the Norwood procedure, but the real incidence and its natural history are unclear. Regular surveillance in these patients after the operation is necessary. Herein, we present an 11-year-old boy born with tricuspid atresia, a discordant ventriculo-arterial connection and a hypoplastic aortic arch, who was palliated initially with a hybrid stage I procedure involving a reversed Blalock-Taussig shunt, followed by comprehensive stage II and then, an extra-cardiac fenestrated Fontan operation. The patient developed an aortic root aneurysm and severe aortic regurgitation. He was electively taken into the operating room, where cardiopulmonary bypass was established through a peripheral cannulation of the femoral vessels due to the high risk nature of the reoperation. A mechanical Bentall procedure was performed without residual lesions and the native ascending aorta was anastomosed as a single coronary button to the anterior wall of the graft.

Foramen ovale and ductus arteriosus hemodynamics in Dextro Transposition of Great Arteries (D-TGA) with intact ventricular septum, case report, and literature review

D-TGA is characterized by discordant Ventriculo-arterial connection. For the patient to survive there should be a mixing of the oxygenated and deoxygenated blood at the atrial, ventricular and/or the great vessel level. The hemodynamics of the PFO and ductus arteriosus in D-TGA with intact ventricular septum (VS) is complex and depends upon the relative difference between the pulmonary and systemic vascular resistance as well as the ventricular compliance. D-TGA with intact VS might be associated with persistent pulmonary hypertension as well as with low pulmonary vascular resistance leading to changes in the hemodynamics and direction of flow through the PDA and/or the PFO. The indications of balloon atrial septestomy as well as the initiation and/or the continuation of Prostaglandin infusion are conflicting issues in such cases. We are presenting a case of D-TGA with intact VS who developed steeling and signs of low systemic blood flow because of a large PDA. We reviewed the hemodynamics of PFO and DA in such cases as well as the indications of BAS and PG infusion.

Anatomical Studies of Transposition – An Argument for a Unifying Morphological Classification

In the setting of transposition, recognition of the variability in the morphology of the outflow tracts and the arterial trunks is essential for surgical repair. Presence of a unifying system for classification would minimize the risk of misunderstanding. We examined an archive of 142 unrepaired hearts with transposition, defined as the combination of concordant atrioventricular and discordant ventriculoarterial connections, combined with the clinical records of 727 patients undergoing the arterial switch procedures. In the setting of usual atrial arrangement, we found the aortic root in leftward or posterior location in up to 5% of our cohorts, making the common term "d-transposition" ambiguous. Variability in the relationship of the trunks was commoner in the setting of deficient ventricular septation, especially when the trunks were side-by-side (14% vs 5.5% when the ventricular septum was intact). Bilateral infundibulums were present in 14% of cases, and bilaterally deficient infundibulums in 3.5%. Both of these findings were more common with deficient ventricular septation. Fibrous continuity between the tricuspid and pulmonary valves was not always seen with perimembranous defects, particularly when there were bilateral infundibulums. Fibrous continuity between the leaflets of the tricuspid and mitral valves, in contrast, proved a unifying characteristic of the perimembranous defect. The combination of concordant atrioventricular and discordant ventriculoarterial connections is best described simply as "transposition," with precision provided when details are given of atrial arrangement and the relationships of the arterial trunks.

AIUM Practice Parameter for the Performance of Fetal Echocardiography.

AIUM Practice Parameter for the Performance of Fetal Echocardiography.

Congenitally corrected transposition of the great arteries: is it really a transposition? An anatomical study of the right ventricular septal surface

Congenitally corrected transposition of the great arteries (ccTGA) is a rare congenital malformation which associates discordant atrioventricular and ventriculo-arterial connections. Although frequently associated with a ventricular septal defect (VSD), its anatomy remains controversial. This could be due in hearts with usual atrial arrangement to the apparently different anatomy of the left-sided right ventricle compared with a right-sided right ventricle. We wanted to compare the RV septal anatomy between ccTGA, transposition of the great arteries and normal heart and to determine the anatomy of the VSD in ccTGA. We analysed 102 human heart specimens: 31 ccTGA, 36 transpositions of the great arteries, 35 normal hearts. According to the last classification of VSD (ICD-11), VSD were classified as outlet if located above the superoseptalcommissure of the tricuspid valve and inlet if underneath. We measured the lengths of the superior and inferior limbs of the septal band and the angle between the two limbs. To assess the orientation of the septal band, we also measured the angle between superior limb and the arterial valve above. A VSD was present in 26 ccTGA (84%) and was an outlet VSD in 16 cases (61%). The mean angle between the two limbs of the septal band was 76.4° for ccTGA compared with 90.6° for transposition of the great arteries (P=0.011) and 76.1° for normal hearts (P= NS). The mean angle between the superior limb of the septal band and the arterial valve above was 70.6° for ccTGA compared with 90.6° for transposition of the great arteries (P=0.0004) and 69.1° for normal hearts (P= NS). The inferior limb of the septal band was significantly shorter in ccTGA (P<0.0003): SL/IL length ratio was 21.4 for ccTGA, 2.2 for transposition of the great arteries and 1.5 for normal hearts. The typical VSD in ccTGA is an outlet VSD. Its frequent misdiagnosis as an inlet VSD might be explained by the shortness of the inferior limb, which creates the illusion of a posterior VSD, and by the fact that the VSD is usually assessed from the left ventricular aspect. Surprisingly, the orientation of the septal band is similar in ccTGA and normal heart, despite the discordant atrioventricular connections, and different in ccTGA and transposition of the great arteries, despite the discordant ventriculo-arterial connections. These findings suggest that the mechanism leading to transposition in ccTGA and in TGA probably is different. The term 'double discordance' might therefore be more appropriate as a description of this complex anomaly.

P5685Abnormal anatomy of the coronary sinus in congenitally corrected transposition of the great arteries (double discordance): a pitfall for transvenous cardiac resynchronization therapy?

Abstract Background Congenitally corrected transposition of the great arteries (ccTGA) or double discordance is a rare congenital heart defect associating discordant atrioventricular and ventriculoarterial connections. Late prognosis depends on the progressive failure of the systemic right ventricle (RV). A possible cause for systemic RV dysfunction could be ventricular asynchrony. Cardiac resynchronization therapy (CRT) may thus be indicated in some cases. However, the cardiologists may experience some problems with the coronary sinus (CS) when implanting a 3-lead CRT transvenous system in these patients. Aim of the study To evaluate the anatomy of the CS and cardiac veins in specimens with ccTGA, in order to assess the feasibility of transvenous CRT. Material and methods Among the anatomic collection of the French Centre of Reference for complex CHD, 51 heart specimens had ccTGA with 2 ventricles. There were 33 post-natal and 18 fetal hearts. Hearts were reviewed with special attention paid to the course and drainage of the CS and cardiac veins. Segmental anatomy, location of the ventricular septal defect (VSD), status of the pulmonary outflow tract and anomalies of the atrioventricular valves were reviewed. Results Segmental anatomy was {S,L,L} in 46/51 hearts, {S,L,D} in 2 and {I,D,D} in 3. There was a VSD in 40 (outlet in 25, inlet in 11, both in 2, muscular in 2), pulmonary atresia in 13, subpulmonary stenosis in 6, abnormal tricuspid valve in 20/48 including Ebstein anomaly in 6, straddling in 9 (3 had replacement). The CS was always located behind the morphologically left atrium (LA). However, its anatomy was normal, with normal drainage into the morphologically right atrium, in only 25/51 (49% of cases). The CS was of reduced length with normal orifice in 17. Orifice was atretic with normal size CS in 2, and CS was completely absent in 6 with direct drainage of coronary veins into the LA. At least 1 available vein was found in all cases with patent CS orifice. Conclusion CS in ccTGA is always located behind the morphologically LA. However, its anatomy is abnormal in half of cases. The most frequent anomalies are reduced length (33%) and absent CS or atretic orifice (15.5%). The anatomy of CS should therefore be assessed by imaging techniques (multislice CT imaging or CS venography) before considering transvenous CRT in these patients.

Postnatal Outcome Following Prenatal Diagnosis of Discordant Atrioventricular and Ventriculoarterial Connections.

Discordant atrioventricular and ventriculoarterial connection(s) (DAVVAC) are a rare group of congenital heart lesions. DAVVAC can be isolated or associated with a variety of other cardiac abnormalities. Previous studies examining the outcome of prenatally diagnosed DAVVAC have described only fetal and early postnatal outcome in small cohorts. We aimed to describe the medium-term outcome of these fetuses. Cases were identified by searching the fetal cardiac databases of two centers. Follow-up data were collected from the electronic patient records. We identified 98 fetuses with DAVVAC. 39 pregnancies were terminated and 51 resulted in a liveborn infant. Postnatal data were available for 43 patients. The median length of follow-up was 9.5years (range 36days to 22.7years). The overall 5-year survival of the cohort was 80% (95% confidence interval 74-86%), no deaths were seen after this period. Associated cardiac lesions had a significant effect on both survival and surgery-free survival. Isolated DAVVAC and DAVVAC with pulmonary stenosis ± ventricular septal defect had a low mortality (89% and 100% 5-year survival, respectively). Poorer survival was seen in the group with Ebstein's anomaly of the tricuspid valve, and other complex cardiac abnormalities. Antenatal tricuspid regurgitation had a significant negative impact on postnatal survival. In conclusion, the short- and medium-term outlook for fetuses with isolated DAVVAC, and those with DAVVAC and pulmonary stenosis are good. Antenatal risk factors for postnatal mortality include Ebstein's anomaly of the tricuspid valve, especially if associated with tricuspid regurgitation, and the presence of complex associated lesions.

Management of the Adult with Arterial Switch.

Dextro-transposition of the great arteries (d-TGA) is a lethal congenital heart defect in which the great arteries-the pulmonary artery and aorta-are transposed to create ventriculoarterial discordance. Corrective surgical interventions have resulted in significant improvements in morbidity and mortality for this once-fatal congenital heart defect. The initial palliative surgery for d-TGA was the atrial switch operation, which provided physiological correction. The Mustard and Senning "atrial switch" procedures, in which an atrial baffle is created to produce a discordant atrioventricular connection on the existing discordant ventriculoarterial connection, showed preliminary success for the correction of d-TGA. However, follow-up evaluations demonstrated increasing complications from the right ventricle utilized as a systemic ventricle, resulting in progressive right ventricular dysfunction. Thus, the search continued for an anatomical correction of d-TGA to return the great arteries to their normal ventricular connections. The arterial switch operation (ASO), though attempted and theorized by many, was first successfully performed by Dr. Jatene and colleagues in 1975. For ASO, the distal main pulmonary artery and the distal ascending aorta are transected and then anastomosed to their respective ventricles with relocation of the coronary arteries to the neoaorta. The ASO has replaced the atrial switch operation since the 1980s and is now the standard surgical correction for d-TGA. As more patients who have undergone ASO are living into adulthood, late complications of this procedure have become more evident. The most common late postoperative complications include coronary artery stenosis, neoaortic root dilation, neoaortic insufficiency, and neopulmonic stenosis. Adults who have undergone ASO in childhood will need follow-up with surveillance imaging and evaluation of new symptoms or declining function to prevent and manage late postoperative complications. This review describes the management strategies for common late complications in patients who have undergone ASO.

Cardiac Conduction System in Congenitally Corrected Transposition of the Great Arteries and Its Clinical Relevance

Congenitally corrected transposition of the great arteries (ccTGA) is a rare cardiac malformation characterized by the combination of discordant atrioventricular and ventriculoarterial connections.1 The incidence has been reported to be around 1/33 000 live births, accounting for ≈0.05% of congenital heart malformations.2 Although a familial recurrence of heart defects in subjects with ccTGA has been reported,3 the etiology of this malformation is not currently known.1, 4 The morphological right atrium is connected to the morphological left ventricle across the mitral valve, with the left ventricle then connected to the pulmonary trunk; the morphological left atrium is connected to the morphological right ventricle across the tricuspid valve, with the morphological right ventricle connected to the aorta. Because of this “double discordance,” the systemic venous return is pumped to the lungs, while the pulmonary venous return is directed to the body. In the context of usual atrial arrangement (situs solitus), the morphological left ventricle is thus positioned to the right and the aorta, arising from the morphological right ventricle, is more commonly left‐sided. In mirror‐image atrial arrangement (situs inversus), the morphological left ventricle is left‐sided, and the aorta is usually positioned to the right. Most patients have at least 1 associated cardiac anomaly, mainly ventricular septal defect (VSD), subvalvular and/or valvular pulmonary stenosis, or abnormalities of the systemic (tricuspid) atrioventricular (AV) valve with coexisting accessory pathways.4 Because of the unusual position of the atrioventricular node and course of the atrioventricular conduction bundle, cardiac conduction disorders are frequent and markedly alter the natural history and management of the malformation.5, 6, 7 This article provides a comprehensive, up‐to‐date description of the characteristics of the cardiac conduction system in patients with ccTGA, their clinical sequelae, and their contemporary management.

Intracardiac anatomical relationships and potential for streaming in double inlet left ventricles.

The aim of this study was to gain better understanding of the variable anatomical features of double inlet left ventricle hearts without cavopulmonary connection that would potentially facilitate favorable streaming. Thirty-nine post-mortem specimens of double inlet left ventricle without cavopulmonary connection were investigated. The focus was on anatomical characteristics that could influence the flow and separation of deoxygenated and oxygenated blood in the ventricles. Elements of interest were the ventriculoarterial connection, the spatial relationship of the ventricles, the position and size of the great arteries, the ventricular septal defect, the presence of relative outflow tract stenosis and the relationship of the inflow and outflow tracts. The most common anatomy was a discordant ventriculoarterial connection with an anatomically left-sided morphologically right ventricle (n = 12, 31%). When looking at the pulmonary trunk/aorta ratio, 21 (72%) hearts showed no pulmonary stenosis relative to the aorta. The ventricular septal defect created a relative subpulmonary or subaortic stenosis in 13 (41%) cases. Sixteen (41%) hearts had a parallel relationship of the inflow and outflow tracts, facilitating separation of deoxygenated and oxygenated blood streams. On the other end of the spectrum were 10 (25%) hearts with a perpendicular relationship, which might lead to maximum mixing of the blood streams. The relationship of the inflow and outflow tracts as well as the presence of (sub-) pulmonary stenosis might play a crucial role in the distribution of blood in double inlet left ventricle hearts. Additional in vivo studies will be necessary to confirm this postulation.

Arterial switch operation in patients with transposition and a left-sided aorta.

Arterial switch operation is the treatment of choice in infants with transposed arterial trunks. It is technically challenging to perform in patients having usual atrial arrangement and concordant atrioventricular connections but having a left-sided aorta. Correction in this setting requires surgical expertise and precision. Here we review our experience with such patients. Between January, 2002 and October, 2013, the arterial switch operation was performed in 20 patients in the combination emphasised above. Patient records were analysed in detail for coronary arterial patterns, and for the techniques used for transfer of the coronary arteries and reconstruction of the great arteries. Outcomes were recorded in terms of in-hospital survival and left ventricular function at the most recent follow-up. All patients survived the procedure. Ages ranged from 3 days to 18 months, with a median of 75 days; the weight of the patients ranged from 3 to 8.8 kg, with a median of 3.85 kg. The LeCompte manoeuvre was performed in only nine patients. The mean cardiopulmonary bypass time was 157.5±24.9, with a median of 161 minutes, and the mean aortic cross-clamp time was 101.2±23.8, with a median of 102 minutes. Subsequently, two patients died: the first due to a sudden onset of ventricular fibrillation and the second during a crisis of severe pulmonary hypertension. At the last follow-up, which ranged from 23 to 41 months, with a mean of 38.04±2.32 and a median of 38.4 months, all 18 survivors were in NYHA class I, with none requiring cardiac medications and all having normal bi-ventricular function without residual defects. With appropriate technical modifications, patients with concordant atrioventricular and discordant ventriculo-arterial connections with a left-sided aorta can undergo successful anatomical repair.