left atrial enlargement
Last reviewed 01/2018
The chest X-ray is a good method for assessing the size of the left atrium.
Signs of left atrial enlargement on chest X-ray include:
- increased density in the region of the left atrium; the increased density extends to the right of the spine
- a curvilinear border of the left atrium is seen through the right heart; this is a visible right-hand margin of the left atrium
- left mainstem bronchus is more horizontal on PA chest radiograph, occasionally there is widening of the carinal angle (normal is 80ø)
Causes include:
- obstruction at the left atrial level
- mitral stenosis or regurgitation
- atrial myxoma
- cor triatriatum
- left ventricular failure
- aortic stenosis or regurgitation
- co-arctation of the aorta