Revisiting the Atrioventricular Conduction Axis for the 21st Century.

In this review, we summarise the ongoing debate surrounding the anatomy of the atrioventricular conduction axis and its relevance to pacing. We highlight previous disagreements and emphasise the importance of understanding the anatomical location of the axis. We give credit and support to the initial descriptions by His and Tawara, in particular their attention to the relationship of the atrioventricular conduction axis with the membranous septum.

Are paediatric cardiology textbooks obsolete in the current digital era?

Introduction: With the rise of online references, podcasts, webinars, self-test tools, and social media, it is worthwhile to understand whether textbooks continue to provide value in medical education, and to assess the capacity they serve during fellowship training.

Methods: A prospective mixed-methods study based on surveys that were disseminated to seven paediatric cardiology fellowship programmes around the world. Participants were asked to read an assigned chapter of textbook, followed by the completion of the survey.

Revisiting the anatomy of the left ventricle in the light of knowledge of its development.

Despite centuries of investigation, certain aspects of left ventricular anatomy remain either controversial or uncertain. We make no claims to have resolved these issues, but our review, based on our current knowledge of development, hopefully identifies the issues requiring further investigation. When first formed, the left ventricle had only inlet and apical components.

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.

The Atrioventricular Conduction Axis Revisited for the 21st Century.

Although first described in the final decade of the 19th century, the axis responsible for atrioventricular conduction has long been the source of multiple controversies. Some of these continue to reverberate. When first described by His, for example, many doubted the existence of the bundle we now name in his honour, while Kent suggested that multiple pathways crossed the atrioventricular junctions in the normal heart.

Revisiting the anatomy of the right ventricle in the light of knowledge of its development.

Controversies continue regarding several aspects of the anatomy of the morphologically right ventricle. There is disagreement as to whether the ventricle should be assessed in bipartite or tripartite fashion, and the number of leaflets to be found in the tricuspid valve. In particular, there is no agreement as to whether a muscular outlet septum is present in the normally constructed heart, nor how many septal components are to be found during normal development.

Which Phenotypes Should We Include in the Hypoplastic Left Heart Syndrome?

The recent special issue of the devoted to hypoplastic left heart syndrome, and its related anomalies, contained significant information of great clinical relevance. Very little attention, however, was devoted to the integrity of ventricular septum as providing a criterion to distinguish between the phenotypes to be included within the syndrome, as opposed to the related anomalies. In this commentary, we summarize the evidence in support of the notion that the phenotypes to be included within the syndrome can be interpreted on the basis of an acquired disease of fetal life.

Relationship between the aortic root and the atrioventricular conduction axis.

Damage to the atrioventricular conduction axis continues to be a problem subsequent to transcatheter implantation of aortic valvar prostheses. Accurate knowledge of the precise relationships of the conduction axis relative to the aortic root could greatly reduce the risk of such problems. Current diagrams highlighting these relationships rightly focus on the membranous septum.

Expert Consensus Statement: Anatomy, Imaging, and Nomenclature of Congenital Aortic Root Malformations.

Over the past 2 decades, several categorizations have been proposed for the abnormalities of the aortic root. These schemes have mostly been devoid of input from specialists of congenital cardiac disease. The aim of this review is to provide a classification, from the perspective of these specialists, based on an understanding of normal and abnormal morphogenesis and anatomy, with emphasis placed on the features of clinical and surgical relevance.

Expert Consensus Statement: Anatomy, Imaging, and Nomenclature of Congenital Aortic Root Malformations.

Over the past 2 decades, several categorizations have been proposed for the abnormalities of the aortic root. These schemes have mostly been devoid of input from specialists of congenital cardiac disease. The aim of this review is to provide a classification, from the perspective of these specialists, based on an understanding of normal and abnormal morphogenesis and anatomy, with emphasis placed on the features of clinical and surgical relevance.

What Is the Hypoplastic Left Heart Syndrome?

As yet, there is no agreed definition for the so-called "hypoplastic left heart syndrome". Even its origin remains contentious. Noonan and Nadas, who as far as we can establish first grouped together patients as belonging to a "syndrome" in 1958, suggested that Lev had named the entity.

Identifying Anomalies of Systemic Venous Drainage: Systemic Venous Anomalies; Atrial Morphology.

So as to produce totally anomalous systemic venous connection, all of the systemic venous tributaries, along with the coronary sinus, should be connected with the morphologically left atrium. Previous descriptions of this rare constellation of anomalous connections of the systemic venous tributaries of the heart have been compromised by the inclusion of individuals having isomeric atrial appendages. In these settings, most frequently, the totally, or almost totally, anomalous systemic venous connections are associated with a sinus venosus defect.

Vulnerability of the ventricular conduction axis during transcatheter aortic valvar implantation: A translational pathologic study.

The ventricular components of the conduction axis remain vulnerable following transcatheter aortic valvar replacement. We aimed to describe features which may be used accurately by interventionalists to predict the precise location of the conduction axis, hoping better to avoid conduction disturbances. We scanned eight normal adult heart specimens by 3T magnetic resonance, using the images to simulate histological sections in order accurately to place the conduction axis back within the heart.

Techniques and pitfalls of coronary arterial reimplantation in anatomical correction of transposition.

Background And Aim: We assessed the anatomical variations in coronary arterial patterns relative to the techniques of reimplantation in the setting of the arterial switch operation, relating the variations to influences on outcomes.

Methods: We reviewed pertinent published investigations, assessing events reported following varied surgical techniques for reimplantation of the coronary arteries in the setting of the arterial switch procedure.

Results: The prevalence of reported adverse events, subsequent to reimplantation, varied from 2% to 11%, with a bimodal presentation of high early and low late incidence.

Is it really a levoatrial cardinal vein?

With the advent of computed tomographic interrogation, it is increasingly frequent to find venous channels that provide direct connections between the pulmonary and systemic veins. These channels, before the introduction of three-dimensional techniques for clinical imaging, were usually found providing an "overflow" for the obstructed left atrium in settings such as hypoplastic left heart syndrome, or divided left atrium. Similar channels, however, had been described almost 100 years ago, with one accurately described as a jugulo-pulmonary vein.

Transposition physiology in the setting of concordant ventriculo-arterial connections.

Background And Aim: To review the anatomical details, diagnostic challenges, associated cardiovascular anomalies, and techniques and outcomes of management, including re-interventions, for the rare instances of transposition physiology with concordant ventriculo-arterial connections.

Methods: We reviewed clinical and necropsy studies on diagnosis and surgical treatment of individuals with transposition physiology and concordant ventriculo-arterial connections, analyzing also individuals with comparable flow patterns in the setting of isomerism.

Results: Among reported cases, just over two-thirds were diagnosed during surgery, after initial palliation, or after necropsy.