The surgical anatomy of hearts with isomeric atrial appendages-implications for surgical management.

Objectives: The most severe combinations of cardiac malformations exist in individuals having jumbled-up thoracic and abdominal organs. These patients make up 2 distinct syndromes. As yet, the consensus is lacking on how best to describe the subsets. The subsets are frequently grouped together in terms of 'heterotaxy'. The surgical approaches to the subsets, however, are markedly different. We reviewed our experiences with regard to the anatomy as observed in the autopsy room, by the analysis of computed tomographic studies, and in the operating room, to assess whether the lesions might be segregated on the basis of isomerism of the atrial appendages.

Methods And Results: A review of our findings from the examination of specimens from several archives, along with investigation of a large cohort of patients being prepared for surgical treatment, showed that individuals can uniformly be segregated into subgroups on the basis of isomeric arrangement of the atrial appendages. In all instances, this was made possible by using the criterion of the extent of the pectinate muscles within the appendages as judged relative to the atrial vestibules. Segregation on this basis, which correlated excellently with the bronchial arrangement, sets the scene for an appropriate description of the remainder of the heart, providing the cardiac surgeon with all the inferences required for appropriate surgical intervention.

Conclusions: When assessing individuals having the features of so-called 'heterotaxy', it is possible to segregate the groups into subsets of individuals having either isomeric right or left atrial appendages. This approach provides the framework for the assessment of appropriate surgical management.