left atrium enlargement

[mevi]

how much enlargement is dangerous?


This discussion is related to Enlarged Left Atrium Consideration.

[Bob007]

The question still remains. Assuming your atria was accurately measured, and it is still larger than 4, how large is dangerous?

Thanks,
Bob

[erijon]

I'm assuming you had an echocardiogram and were told your LA was enlarged. You have to understand the limitations of echocardiography in assessing left atrial size: although they are telling you that it is dilated and the upper limit of normal is 4 cm, it may actually not be dilated at all. This measurement was most likely obtained on a single 'slice' of the atrium and may not be representatitive of actual left atrial size. For instance if you slice a banana perpendicular to its long axis you may get a small value, but if you cut it at a 45 degreee angle you may get a larger value: simply because you were not perpendicular to its main axis. Often patients, especially patients who may have been heavier in the past do not have the standard orientation in the chest and may be rotated to the left, causing the standard echocardiographic views to be off axis and the consequent innacuracies in measurements. The most accurate way to measure the left atrial size is to report atrial volumes,  but this is difficult to assess in most patients, and in general has very little prognostic value in most patients. The exception are patients with atrial fibrillation who have a likelyhood of responding to treatment.

Hope this helps,

Jon