Anatomically corrected malposition of the great arteries

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.

Concordant ventriculoarterial connections with parallel arterial trunks in the setting of isomerism of the right atrial appendages

We describe an autopsied specimen, from an infant who died in 1967, in which concordant ventriculoarterial connections coexisted with parallel arterial trunks, usually described as "anatomically corrected malposition." Based on their shape, the extent of the pectinate muscles, and the absence of a coronary sinus, we diagnosed isomeric right atrial appendages. Despite this, the arrangement of the remaining thoracic and abdominal organs, as well as the patterns of venous drainage, was almost completely mirror imaged.