What is aortic overriding?

Robert H. Anderson*, Diane E. Spicer, G. William Henry, Cynthia Rigsby, Anthony M. Hlavacek, Timothy J. Mohun

*Corresponding author for this work

Research output: Contribution to journalReview articlepeer-review

6 Scopus citations


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.

Original languageEnglish (US)
Pages (from-to)612-625
Number of pages14
JournalCardiology in the young
Issue number4
StatePublished - Jun 23 2015


  • Dextroposition
  • cardiac development
  • double outlet right ventricle
  • eisenmenger defect
  • interventricular communication
  • tetralogy of Fallot
  • transposition

ASJC Scopus subject areas

  • Pediatrics, Perinatology, and Child Health
  • Cardiology and Cardiovascular Medicine

Fingerprint Dive into the research topics of 'What is aortic overriding?'. Together they form a unique fingerprint.

Cite this