Isolated atrioventricular discordance

Case Report: Atrial baffles of pulmonary and systemic veins for the anatomic and physiologic repair of left atrial isomerism heterotaxy-pre- and post-operative three-dimensional reconstructions of two mirror-image pediatric hearts

Intra-atrial baffles of pulmonary and systemic venous flows are relatively rarely used but are important surgical procedures for late-presenting d-transposition of the great arteries (D-TGA) or heterotaxy with anomalous venous connections. Atrial baffle surgery is employed less frequently today due to the advent of the arterial switch procedure. Two children presented with mirror-image venous connections in polysplenic heterotaxy and underwent intra-atrial baffle biventricular repairs. Both cases had ipsilateral pulmonary venous connections, interrupted inferior vena cava with azygous continuation, and concordant ventriculo-arterial connections. Furthermore, a single superior vena cava receiving the azygous and hepatic veins connected to the atrium contralateral to the sub-pulmonary right ventricle was present in both cases. Volumetric cardiac imaging using computed tomography and magnetic resonance imaging allowed for the creation of three-dimensional (3D) model reconstructions for pre-operative surgical planning and postoperative assessment of the atrial baffle pathways. The 3D model reconstructions presented here provide improved visualization and understanding of complex surgical atrial baffles.

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.

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.

Successful management of isolated ventricular inversion in an adult

We report a case of isolated ventricular inversion in a 42-year-old woman. This rare congenital cardiac anomaly was corrected by an intraatrial baffle procedure. She also underwent left-sided double-chamber endocardial pacemaker implantation for postoperative tachycardia bradycardia syndrome.

Intraatrial baffle repair of isolated ventricular inversion with left atrial isomerism

Isolated ventricular inversion with left atrial isomerism, partial anomalous pulmonary venous connection, and interruption of the inferior vena cava with azygos continuation to a right superior vena cava was diagnosed by echocardiography in a neonate. At 48 days of age, the patient underwent successful anatomic correction with redirection of flow from the superior vena cava and hepatic veins to the left-sided tricuspid valve, and flow from the pulmonary veins to the right-sided mitral valve. In the present report, the surgical techniques of this case are described, along with a survey of the surgical literature covering anatomic repair of isolated ventricular inversion.

Echocardiographic and anatomic findings in atrioventricular discordance with ventriculoarterial concordance

Atrioventricular (AV) discordance with ventriculoarterial (VA) concordance is a rare form of congenital heart disease that consists of 5 different anatomic types. The salient therapeutic consideration uniting these 5 different anatomic entities is that anatomic correction can be achieved by an atrial switch procedure with closure of any associated septal defect. Three patients who had AV discordance with VA concordance are presented, with emphasis upon 2-dimensional echocardiographic diagnosis and surgical management. One of these patients had ventricular inversion with inverted normally related great arteries in situs solitus (i.e., [S,L,I]), thus representing a form of congenital heart disease that until now has not been documented anatomically. Although these are complex defects, multiple-plane imaging with 2-dimensional echocardiography was found to be extremely reliable in ascertaining the anatomy when a comprehensive, segmental analysis is applied. This approach includes determination of visceroatrial situs, ventricular loop and great arterial position and alignment. A surgical approach to closure of the ventricular septal defect through the left-sided infundibulum in isolated ventricular inversion afforded excellent exposure of the defect and avoided AV conduction block.

Isolated ventricular inversion with situs solitus: successful surgical repair

A 7-month-old infant with ventricular inversion without transposition of the great arteries in situs solitus, associated with a ventricular septal defect, is reported. When the infant was 13 months of age, successful surgical repair was undertaken by performing an intraatrial transposition of venous return using the Senning procedure and by closing the ventricular septal defect with a patch. The postoperative course was uneventful except for a well-tolerated complete heart block. No systemic valve incompetence appeared during the 53 months of actual follow-up. A complete review of the literature suggests that this is the sixth reported instance of successful repair. Injury of the abnormally located conduction tissue is regarded as the most threatening complication.