Hearts with concordant ventriculoarterial connections but parallel arterial trunks

Double Outlet of Both Ventricles With an Unusual Relationship of the Great Arteries

Double outlet both ventricles (DOBV) is a rare form of ventriculo-arterial connection wherein the outlet septum is perpendicular to the crest of the apical muscular ventricular septum, thus committing both arterial roots equally to both ventricles. The anomaly has been described in very few reports, with clinical reports being even rarer. We report perhaps the first case of DOBV in which the relationship of the arterial roots themselves is discordant relative to the ventricular topology.

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. Of the patients, four-fifths presented in infancy with either cyanosis or congestive cardiac failure, with complex associated cardiac malformations. Nearly half had ventricular septal defects, and one-fifth had abnormalities of the tricuspid valve, including hypoplasia of the morphologically right ventricle. A small minority had common atrioventricular junctions We included cases reported with isomerism when the flow patterns were comparable, although the atrioventricular connections are mixed in this setting. Management mostly involved construction of intraatrial baffles, along with correction of coexisting anomalies, either together or multistaged. Overall mortality was 25%, with one-fifth of patients requiring pacemakers for surgically-induced heart block. The majority of survivors were in good functional state.

CONCLUSIONS

The flow patterns produced by discordant atrioventricular and concordant ventriculo-arterial connections remain an important, albeit rare, indication for atrial redirection or hemi-Mustard's procedure with bidirectional Glenn. The procedure recruits the morphologically left ventricle in the systemic circuit, producing good long-term functional results. The approach can also be used for those with isomeric atrial appendages and comparable hemodynamic circuits.

Anatomically corrected malposition of the great arteries (S,L,D) with mutation of Nodal gene

Anatomically corrected malposition of the great arteries is a rare CHD, involving alignment and position of the great arteries. We report an infant with situs solitus, atrioventricular discordance, and ventriculoarterial concordance with the aorta arising anteriorly and to the right of the pulmonary artery. A mutation of Nodal gene, implicated in the pathogenesis of human left-right patterning defects, was found.

An unusual case of concordant ventriculoarterial connections, subpulmonary infundibulum, and parallel arterial trunks: a diagnostic challenge

We present an unusual case of concordant ventriculoarterial connections, subpulmonary infundibulum, and parallel arterial trunks. This case was complicated by extreme pulmonary artery tortuosity and low arching aorta causing severe tracheal compression. We discuss the difficulty in prenatal diagnosis, necessity for advanced imaging postnatally, and associated airway complications.

Double Outlet Right Ventricle With Right-Sided Aorta From the Left-Sided Morphologically Right Ventricle in the Setting of Discordant Atrioventricular Connections

We describe the anatomic findings in a 2-year-old patient with double outlet right ventricle with right-sided aorta in the setting of usual atrial arrangement and discordant atrioventricular connections, making comparison with a specimen from the pathological archive of the Birmingham Children's Hospital in the United Kingdom having this rare combination of anatomic features. We discuss the challenges involved in diagnosis and management.

How should we diagnose and differentiate hearts with double-outlet right ventricle?

Many, if not most, of the controversies regarding the description of the congenitally malformed heart have been resolved over the turn of the 20th century. A group of lesions that remains contentious is the situation in which both arterial trunks, in their greater part, are supported by the morphologically right ventricle. It was considered, for many years, that presence of bilateral infundibulums, or conuses, was a necessity for such a diagnosis. It has now been appreciated that this suggestion founders on many counts. In the first instance, such bilateral infundibulums are to be found in patients with other ventriculo-arterial connections, including the otherwise normal heart. In the second instance, it is clear that such an approach abrogates the important principle now known as the morphological method. This states that entities should be defined in terms of their intrinsic morphology and not on the basis of other variable features. It is now also clear that, when assessed simply on the basis of the ventricular origin of the arterial trunks, a significant number of patients fulfil the criteria for so-called "200%" origin of the trunks from the right ventricle when there is fibrous continuity between the leaflets of the atrioventricular and arterial valves. In this review, we show how attention to the morphology of the channel between the ventricles now provides the key to accurately diagnose the ventriculo-arterial connection in patients with suspected double-outlet right ventricle. This is because, when both arterial trunks arise exclusively or predominantly from the morphologically right ventricle, the outlet septum, of necessity, is itself a right ventricular structure. The channel between the ventricles, therefore, is roofed by the inner heart curvature, whether that structure is fibrous or muscular. Our observations then confirm that it is the attachment of the outlet septum, which itself can be muscular or fibrous, which determines the commitment of the interventricular communication to the subarterial outlets. The interventricular communication itself, when directly committed to the ventricular outlets, opens between the limbs of the septomarginal trabeculation or septal band. The defect is subaortic when the outlet septum is attached to the cranial limb of the trabeculation, subpulmonary when attached to the caudal limb, and doubly committed when attached to the inner heart curvature in the roof of the defect. Non-committed defects are no longer positioned within the limbs of the septomarginal trabeculation. Although readily demonstrable by a skilled echocardiographer, we show how these anatomical features are more easily demonstrated with added accuracy when using CT data sets.

Inferior and right-sided juxtaposition of the left atrial appendage with an unexpected type of inter-atrial communication

We have re-investigated an unusual cardiac specimen with juxtaposition of the atrial appendages. The original description dates to 1962, when the autopsy was performed at the Children's Memorial Hospital in Chicago, now Ann & Robert H. Lurie Children's Hospital of Chicago. The heart was subsequently stored in the Farouk S. Idriss Cardiac Registry at the same institution. The specimen shows usual atrial arrangement, but with the morphologically left appendage juxtaposed in a rightward manner, passing behind the heart rather than through the transverse sinus so as to reach its location inferior to the morphologically right appendage. The heart also demonstrated an inter-atrial communication between the cavities of the juxtaposed left appendage and the morphologically right atrium. We provide a detailed description of the morphology, and provide images of this lesion, which to the best of our knowledge has not previously been described.

Problems in the diagnosis of discordant atrioventricular with concordant ventriculo-arterial connections: anatomical considerations, surgical management, and long-term outcome

BACKGROUND

Discordant atrioventricular with concordant ventriculo-arterial connections is a rare cardiac defect. When isolated, the haemodynamics resemble transposition of the great arteries. In complex heart defects such as heterotaxy, haemodynamics guide the surgical approach.

OBJECTIVE

To report a series of eight patients with discordant atrioventricular and concordant ventriculo-arterial connections focussing on anatomical and diagnostic difficulties, surgical management, and follow-up.

METHODS

A retrospective review was carried out from 1983 to 2013. Anatomical description was based on segmental analysis. Emphasis was placed on the venoatrial connections.

RESULTS

Segmental arrangement was {I, D, S} in six patients, all with spiralling great vessels. There were two patients with parallel great vessels of whom one had {S, L, D} and the other had {S, L, A} arrangement. Of eight patients, five had heterotaxy syndrome. Median age at repair surgery was 1.4 years (with a range from 1.1 months to 8.1 years). The repair surgery finally performed was the atrial switch procedure in seven out of eight patients. The main post-operative complications were two cases of baffle obstruction and one sick sinus syndrome needing pacemaker implantation. There were two early post-operative deaths and six late survivors. Median follow-up was 4.2 years (with a range from 3.9 to 26.7 years) with good functional status in all survivors. Discussion Diagnosing discordant atrioventricular with concordant ventriculo-arterial connections remains challenging. There are ongoing controversies about the definition of atrial morphology and heterotaxy syndrome animating the anatomic discussion of these complex heart defects. Haemodynamically, the atrial switch procedure is the surgical method of choice with an encouraging long-term follow-up despite rhythm disturbances and baffle obstruction.

Clarifying the anatomy of hearts with concordant ventriculo-arterial connections but abnormally related arterial trunks

Hearts in which the arterial trunks arise from the morphologically appropriate ventricles, but in a parallel manner, rather than the usual spiralling arrangement, have long fascinated anatomists. These rare entities, for quite some time, were considered embryological impossibilities, but ongoing experience has shown that they can be found in various segmental combinations. Problems still exist about how best to describe them, as the different variants are often described with esoteric terms, such as anatomically corrected malposition or isolated ventricular inversion. In this review, based on our combined clinical and morphological experience, we demonstrate that the essential feature of all hearts described in this manner is a parallel arrangement of the arterial trunks as they exit from the ventricular mass. We show that the relationship of the arterial roots needs to be described in terms of the underlying ventricular topology, rather than according to the arrangement of the atrial chambers. We then discuss the importance of determining atrial arrangement on the basis of the morphology of the appendages, following the precepts as set out in the so-called "morphological method" and distinguished according to the extent of the pectinate muscles relative to the atrioventricular junctions as opposed to basing diagnosis on the venoatrial connections. We show that, when approached in this manner, the various combinations can be readily diagnosed in the clinical setting and described in straightforward way.

What is aortic overriding?

BACKGROUND

Disagreement currently exists regarding the definition of aortic dextroposition. It is suggested that the term be used interchangeably with aortic overriding, along with suggestions that the aortic valve overrides in the normal heart. The dextroposed aorta, however, does not always override the crest of the muscular ventricular septum. It is incorrect to argue that the normal aortic valve overrides. It is the cavity of the right aortic valvar sinus, rather than the valvar orifice, that sits above the muscular septum when the septum itself is intact. Therefore, to circumvent these difficulties, those using the term "dextroposition" find it necessary to distinguish "true" as opposed to "false" categories. The problems arise because "dextroposition" is remarkably ill-suited as an alternative term for aortic valvar overriding.

METHODS AND RESULTS

In this review, combining developmental, morphologic, and clinical data, we show how aortic overriding is best considered on the basis of biventricular connection of the aortic root in the setting of deficient ventricular septation. When analysed in this manner, it becomes an easy matter to distinguish between one-to-one and double outlet ventriculo-arterial connections. Appreciation of these features emphasises the different spatial alignments of interventricular communications as opposed to the plane of deficient ventricular septation. The concept of overriding is applicable not only to biventricular connection of the aortic root, but also the pulmonary and common arterial roots.

CONCLUSIONS

The diagnostic techniques now available to the paediatric cardiologist illustrate the features of arterial valvar overriding with exquisite accuracy, informing the discussions now required for optimal decision making.

Concordant ventriculoarterial connections with parallel arterial trunks, divided left atrium, and juxtaposed atrial appendages

We describe a patient with concordant ventriculoarterial connections with parallel arterial trunks, divided left atrium (cor triatriatum sinister), ventricular septal defect, bilateral superior caval veins, and juxtaposed atrial appendages. The aorta was anterior and left sided. We discuss the morphological features of this rare condition, and the diagnostic dilemma it produced.

Parallel arterial trunks with discordant atrioventricular and concordant ventriculo-arterial connections in mirror-imaged arrangement

Cardiac malformations are very rare in which the great arteries arise from their appropriate ventricles, but are abnormally related to each other. Here, we present a patient with mirror-imaged atrial arrangement and a left-sided heart who has parallel arterial trunks with discordant atrioventricular and concordant ventriculo-arterial connections. The ventricles were related in supero-inferior fashion, the left ventricle being anterior and superior, this being an additional feature which, to the best of our knowledge, has not previously been described in this setting.