Left atrial enlargement chest x-ray

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-In-Chief: Cafer Zorkun, M.D., Ph.D. [2]; Varun Kumar, M.B.B.S. [3]

Chest X-Ray

Chest x-ray findings of left atrial enlargement are:

Double density sign: Occur when the right side of the left atrium pushes behind the right atrial border, appearing as a double density. If large enough it can actually reach beyond the border of the right atrium.
Convex left atria appendage: usually reflect prior rheumatic heart disease
Splaying of the carina
Posterior displacement of the left main stem bronchus on lateral radiograph
Superior displacement of the left main stem bronchus on frontal view
Posterior displacement of a barium filled oesophagus or nasogastric tube

Images shown below are courtesy of Radiopedia.com.

Double density sign
Same patient & the same image. Double density sign. Image’s modified for more contrast and better visualization.
Aside from the dirty lung due to emphysema and pneumonic infiltration in the lower right field you can notice a marked enlargement of the left atrium with splaying of the carina.

References

Chest X-Ray