Ventricular septal defect in congenital heart defects : from the anatomical point to the 3D reconstruction

Partie1 : la communication interventriculaire (CIV) est la cardiopathie congénitale la plus courante et fait partie intégrante de la plupart des malformations cardiaques congénitales complexes. Dans ce travail, nous avons essayé de déterminer la distribution des types anatomiques de CIV dans diverses cardiopathies congénitales (CC). Nous avons étudié 1178 spécimens atteints de cardiopathie congénitale provenant de la collection anatomique du Centre français de référence pour malformations cardiaques congénitales complexes. Au cours de l'étude morphologique, une attention particulière a été portée à l'anatomie de la CIV vue du côté ventriculaire droit. Notre premier résultat sur les cardiopathies de la voie d'éjection était que toutes ces CC partagent le même type anatomique de CIV. Les différences anatomiques entre ces cardiopathies de la voie d'éjection est la continuité fibreuse entre la valve aortique et tricuspide et l'orientation du septum en conal. Cette différence suggère un continuum anatomique allant de l'interruption de l'arche aortique (IAA) jusqu'au tronc artériel commun, plutôt que des phénotypes physiologiques distincts. Cela pourrait s'expliquer embryologiquement par un défaut de rotation de la voie d'éjection pendant le wedging. Dans le sous-groupe des IAA, la CIV dans l'IAA de type B est toujours une CIV de la voie d'éjection. Dans l'IAA de type A, la CIV peut être de tout type. Ce résultat renforce l'hypothèse de différents mécanismes pathogènes responsables des 2 types d'IAA et l'inclusion d'IAA de type B dans le groupe des cardiopathies de la crête neurale. Nous avons examiné la distribution anatomique de la CIV dans les CC et avons constaté que la distribution des types anatomiques des CIV est similaire dans les CIV isolées, la coarctation aortique et la transposition des gros vaisseaux (TGV), tandis que la CIV est principalement une CIV de la voie d'éjection dans les cardiopathies de la voie d'éjection, à l'exception de la TGV. Cela renforce les mécanismes prétendument différents de l'AGT et des défauts dits de la crête neurale cardiaque. Cette approche anatomique pourrait fournir de nouvelles informations sur le groupement et l'étiologie des cardiopathies congénitales. Partie 2 : l'un des facteurs clés de succès du traitement chirurgical des malformations cardiaques congénitales complexes reste une compréhension détaillée et approfondie de l'anatomie intracardiaque. Actuellement, les spécimens cardiaques sont les meilleurs outils pédagogiques disponibles pour étudier les relations spatiales des différentes composantes du cœur dans les malformations cardiaques congénitales complexes, telles que le ventricule droit à double issue (VDDI). Cependant, l'accès aux collections anatomiques n'est possible que dans quelques centres dans le monde et les spécimens peuvent être endommagés avec le temps. Nous avons décidé d'étudier l'anatomie intracardiaque dans le VDDI en utilisant l'imagerie 3D de spécimens cardiaques. L'objectif secondaire est de créer une base de données à des fins pédagogiques. Nous avons effectué des scanners à haute résolution sur des échantillons cardiaques présentant divers types anatomiques de cardiopathies complexes avec CIV. Les spécimens ont été fixés dans du formol à 10%. Toutes les images 3D ont été produites avec une plate-forme de reconstruction 3D. La vue 3D par les ventricules droit et gauche montrait les détails anatomiques de manière très nette pour tous les cœurs. Nous avons décrit le CIV, sa localisation, ses limites et sa surface. Nous avons également décrit la relation entre la CIV et les gros vaisseaux, ainsi que la longueur et l'orientation du septum conal. La capacité de naviguer dans les cavités et les vaisseaux cardiaques était très utile pour comprendre l'anatomie spécifique des malformations.Part1: The ventricular septal defect (VSD) is the most common congenital heart disease and is an integral part of most complex congenital heart defects (CHD). In this work we tried to determine the distribution of the anatomic types of VSD in various CHD. We studied for this research 1178 heart specimens with CHD from the anatomic collection of the French Reference Center for Complex Congenital Heart Defects. During the morphologic study, special attention was paid to the anatomy of the VSD viewed from the right ventricular side. Our first result on outflow tract defects (OTD) was that all these defects share the same VSD, outlet in type. The anatomic differences between OTD regarding aortic-tricuspid continuity and the anatomy of the outlet septum suggest an anatomic continuum from interruption of the aortic arch (IAA) and VSD to common arterial trunk (CAT), rather than distinct physiological phenotypes. This could be explained embryologically by a defective rotation of the outflow tract. In the subgroup of IAA, the VSD in IAA type B is always an outlet VSD, in IAA type A the VSD can be of any type. This result reinforces the hypothesis of different pathogenic mechanisms responsible for the 2 types of IAA, and the inclusion of IAA type B in the group of cardiac neural crest defects. Conversely, IAA type A could be due to overlapping mechanisms: flow-related defect (coarctation-like) and neural crest contribution. We looked at the anatomic distribution of VSD in CHDs and we found that the VSD is similar in isolated VSD, aortic coarctation and transposition of the great arteries (TGA), while the VSD is predominantly outlet in outflow tract defects except TGA. This reinforces the allegedly different mechanisms in TGA and so-called cardiac neural crest defects. This anatomic approach could provide new insights in the grouping and etiology of CHD. Part2: One of the key success factors of the surgical treatment of complex congenital heart defects remains a detailed and in-depth understanding of the intracardiac anatomy. Currently, heart specimens are the best available teaching tools for studying the spatial relationships of the various components of the heart in complex congenital heart defects, like double outlet right ventricle (DORV). However, the access to anatomic collections is possible in only a few centres worldwide, and heart specimens may become damaged with time. We decided to study the intracardiac anatomy in DORV by using 3D imaging of heart specimens. The secondary objective is to build a database for teaching purposes. We performed CT scans with high resolution in heart specimens with various anatomic types of complex CHD with VSD. Heart specimens were fixed in 10% formalin. Openings were carefully stitched together before putting the heart in the CT scan. All 3D images were produced with a 3D reconstruction platform. The 3D view from the right and left ventricles showed the anatomic details very neatly for all hearts. We described the VSD, its localization, borders and surface. We described also the relationship of the VSD with the aorta and the pulmonary trunk and the length and orientation of the outlet septum. The ability to navigate through the heart cavities and vessels was very useful to understand the specific anatomy of the malformations. This study underlines the role of 3D scan reconstruction as an imaging modality to increase our understanding of the anatomy of complex congenital hearts defects like DORV. This could constitute an innovative pedagogic approach, and a way to preserve the anatomic collections in the future

Devenir après prise en charge des lésions coronaires survenues après switch artériel dans la transposition des gros vaisseaux

LILLE2-BU Santé-Recherche (593502101) / SudocSudocFranceF

Anatomy of the ventricular septal defect in congenital heart defects: a random association?

Abstract Background A ventricular septal defect (VSD) is an integral part of most congenital heart defects (CHD). To determine the prevalence of VSD in various types of CHD and the distribution of their anatomic types. Methods We reviewed 1178 heart specimens with CHD from the anatomic collection of the French Reference Centre for Complex Congenital Heart Defects. During the morphologic study a special attention was paid to the localisation of the VSD viewed from the right ventricular side. The VSDs were classified as muscular, central perimembranous, outlet located between the two limbs of the septal band, and inlet. The specimens were classified according to the 9 categories and 23 subcategories of the anatomic and clinical classification of CHD1 (ACC-CHD). Results Ventricular septum was almost always intact in anomalies of pulmonary veins (4/73, 5%), Ebstein anomaly (3/21, 14%), and double-inlet right ventricle (DIRV, 1/10, 10%). There was always a VSD in tetralogy of Fallot and variants (TOF, 123 cases) and common arterial trunk (CAT, 55 cases), always of the outlet type. There was almost always a VSD in double inlet left ventricle (33/34, 97%, always muscular), congenitally corrected transposition of great arteries (ccTGA, 23/24, 96%), interrupted aortic arch (IAA, 25/27, 93%), and double outlet right ventricle (DORV, 92/106, 87%). A VSD was found in 68% of aortic coarctation (CoA, 43/63), 62% of heterotaxy syndromes (21/34), 54% of transposition of the great arteries (TGA, 104/194). The VSD was located between the two limbs of the septal band in 100% of TOF and CAT, 80% of IAA, 77% of DORV, 82% of DD. The VSD was of the inlet type in 17% of cc TGA and in 71% of heterotaxy syndromes. In TGA, the VSD was outlet in 40%, central perimembranous in 25%, muscular in 25%, inlet in 10%. In CoA, the VSD was outlet in 44%, central perimembranous in 35%, muscular in 21%. In the 10% hearts with isolated VSD, the distribution was outlet in 44%, central perimembranous in 36%, muscular in 18%, and inlet in 2%. Conclusion The anatomic distribution of VSD is similar in isolated VSD, CoA and TGA, while the VSD is predominantly outlet in outflow tract defects except TGA. This reinforces the allegedly different mechanisms in TGA and cardiac neural crest defects. This anatomic approach could provide new insights in the grouping and aetiology of CHD

0471: Left juxtaposition of the atrial appendages: where are the pectinate muscles?

Left juxtaposition of the atrial appendages (LJAA) is a rare anomaly in which the two atrial appendages (AA) are located to the left of the great arteries (GA). Although several anatomic studies have been published, the internal architecture of the right atrium (RA) in LJAA was not well described.We reviewed 21 postnatal and 5 fetal human heart specimens with L-JAA. All had normal atrial situs, concordant atrioventricular and discordant ventriculoarterial connections: 20 D-transposition, 6 L-transposition. None had heterotaxy. There were 11 transpositions of the GA, 8 double outlet right ventricle, 3 double-inlet left ventricle, 4 tricuspid atresia. The conus was always abnormal, bilateral in 22, subaortic in 4. Pectinate muscles (PM) were confined inside the right AA (RAA) in 20/26 hearts (77%, group 1) and spilled out it without extending to the crux in 6 (group 2). In 9 of group 1 and 4 of group 2, there was a small accessory RAA in normal position with PM inside it (p=ns). The only significant difference between the 2 groups was the incidence of hypoplastic right ventricle (65% in group 1 vs 0 in group 2, p<0.03).ConclusionIn 77% of LJAA, PM do not extend to the crux and can be completely absent of the RA wall. This suggests that PM are constitutive of the morphologically RA only if the RAA is in normal position and raises several questions concerning the development of the atria. In other terms, the extent of the PM (to the crux of the heart or not) might be determined by the situation of the RAA relative to the great vessels, and thus would not be an intrinsic property of the morphologically RA. Normal atrial situs and absence of heterotaxy could indicate that outpouching of the AA from atrial walls might occur after the establishment of the left-right asymmetry, as assessed in one of the rare experimental models of LJAA. Further experimental studies are warranted to elucidate this anatomic and embryologic enigma

0228: Impact of the precision of prenatal diagnostic of congenital heart diseases on perinatal and long-term management

ObjectiveTo evaluate the impact of precising prenatal diagnosis of congenital heart diseases (CHD) on perinatal and long-term management.MethodsOver a 10-year period, 1258 neonates with a prenatally diagnosed CHD and 189 fetal autopsies after termination of pregnancy were included. Changes in CHD diagnosis were classified as totally different, similar but leading to changes in neonatal management, and similar without changes on initial management. The impact on long-term outcome was considered negative if the final diagnosis was a more complex CHD precluding the planned biventricular repair, or if additional surgical interventions were needed, or if the complexity level of the Aristotle score was increased. The impact on outcome was considered positive if biventricular repair was possible while not planned prenatally, or if the number of surgical interventions was reduced, or if the complexity level of the Aristotle score was lower.ResultsThe post-natal diagnosis was imprecise in 30.2% of the cases: completely different in 2.9%, led to changes in initial management in 8%, and did not affect initial management in 19.3%. Imprecision in the prenatal diagnosis had a negative impact on long-term outcome in 4.9% of the cases, and a positive impact in 4.1%.In the fetal autopsy group (mean term 26 weeks), the diagnosis was imprecise in 54.5% of the cases: completely different in 8.5%, could have led to changes in postnatal management in 14.3%, and with minor differences that would not have led to changes in management in 31.7%. In both groups, the most frequent differences were anomalies of the outflow tract anatomy (43%), and the systemic or pulmonary veins (25%).ConclusionImprecision of prenatal diagnosis of CHD changes early management in 11% of the cases, and impacts long-term outcome in 9% of the cases. Improvement of CHD diagnosis for anatomy of the outflow tract and main veins should help to reduce impact on postnatal management and outcome