It depends on what has caused the enlargement.
The left atrium is the chamber of the heart that receives oxygen-rich blood from the lungs. Blood moves from the left atrium through the mitral valve into the main pumping chamber of the heart -- the left ventricle -- and then out to the body. Any condition that increases pressure in this portion of the cardiac system can lead to enlargement of the left atrium. Conditions that lead to left atrial enlargement include hypertension, heart valve problems, heart failure and atrial fibrillation.
Of course hypertension is easier to manage than heart failure.
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