Double density sign (left atrium)

Last revised by Andrew Murphy ◉ on 31 Jul 2022

Citation, DOI, disclosures and article data

Citation:

Gaillard F, Murphy A, Lukies M, et al. Double density sign (left atrium). Reference article, Radiopaedia.org (Accessed on 04 Jun 2023) https://doi.org/10.53347/rID-20322

DOI:

https://doi.org/10.53347/rID-20322

Permalink:

https://radiopaedia.org/articles/20322

rID:

20322

Article created:

13 Nov 2012, Frank Gaillard ◉ ◈

Disclosures:

At the time the article was created Frank Gaillard had no recorded disclosures.

View Frank Gaillard's current disclosures

Last revised:

31 Jul 2022, Andrew Murphy ◉

Disclosures:

At the time the article was last revised Andrew Murphy had no recorded disclosures.

View Andrew Murphy's current disclosures

Revisions:

18 times, by 9 contributors - see full revision history and disclosures

Systems:

Cardiac

Sections:

Signs

Tags:

chest x-ray

Synonyms:

Double right heart border
Double contour sign
Double contour sign of left atrial enlargement
Right retrocardiac double density

The double-density sign, also known as the double right heart border, is seen on frontal chest radiographs in the presence of left atrial enlargement, and occurs when the right side of the left atrium extends behind the right cardiac shadow, indenting the adjacent lung and forming its own distinct silhouette ^1-3.

If large enough, the left atrium can actually reach beyond the border of the right atrium; this is known as atrial escape ³. The right superior pulmonary vein can lead to a similar appearance ¹.