Related Experiment Video
Updated: Jun 18, 2026

11:09
RBDT: A Computerized Task System based in Transposition for the Continuous Analysis of Relational Behavior Dynamics in Humans
Published on: July 17, 2021
Rethinking the "D-" and " L-" prefix paradigm for transposition.
Sarv Priya1, Prashant Nagpal1, Robert H Anderson2
1Department of Radiology, University of Wisconsin, Madison, WI, 53792 USA.
Radiology Case Reports
|June 17, 2026
Summary
The prefixes "D-" and "L-" for great arteries transposition (TGA) describe aortic position, not connections. This can cause miscommunication; a full segmental description is essential for accurate clinical understanding.
Area of Science:
- Cardiology
- Medical Education
- Anatomy
Background:
- The terms "D-" and "L-" are commonly used to describe segmental connections in transposition of the great arteries (TGA).
- Historically, these prefixes denoted the spatial relationship of the aortic root to the pulmonary trunk at the semilunar valve level.
- Their use persists despite not reflecting the underlying atrioventricular (AV) or ventriculo-arterial (VA) connections.
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