Atrial septal pouch: a comprehensive morphologic and morphometric evaluation with clinical relevance

Area of Science:

• Cardiovascular Anatomy
• Cardiac Morphology

Background:

• The septal pouch is an anatomical variant formed by incomplete fusion of the septum primum and septum secundum.
• This variant can predispose individuals to thrombus formation and increase thromboembolic risk.

Purpose of the Study:

• To evaluate the prevalence, morphology, and morphometry of septal pouches.
• To investigate associations between septal pouches and other septal defects.

Main Methods:

• Examination of interatrial septa from 60 human cadaveric hearts.
• Documentation of pouch characteristics: type, orientation, dimensions, and variants.

Main Results:

• Septal pouches identified in 37% (22/60) of hearts.
• Right atrial septal pouches (RSPs) were more prevalent (30%) than left atrial septal pouches (LSPs) (7%).
• Morphological variations noted, with RSPs showing diverse presentations and LSPs being consistently thin and flattened.

Conclusions:

• Septal pouches, particularly RSPs, exhibit significant prevalence and morphometric variability.
• The potential clinical implications of septal pouches in thromboembolic events warrant further research in cardiovascular disease.