Brief Answer:
Changes have happened

Detailed Answer:
Greetings and welcome to HCM. Thank you for your question. I read your query.

No such treatment can treat atrial enlargement. Actually, it is not a "disease" that should be treated. For many reasons, common or rare, atrium may get enlarged during lifespan. It is (most conmonly) a process that starts early and the main happening is that atria's muscle loses flexibility and fibrotic, non-functional tissue takes place in-between these cardiac muscle fibers.
The term "enlargement" derives from the enlarged atrial cavity that produces the above described pathophysiological phenomenon. If there is a known cause/disorder causing atrial dilation, let us take it for instance - hyperthyroidism, then treating the basic problem may be associated with atrial diameter returning to normal figures.
However, it is not to be feared, and it is not malignant, as long as complications that may be produced by this phenomenon, such as atrial fibrillation/flutter, are prevented and treated properly.

I hope I was helpful with my answer.
I am happy to help, if you have follow-up questions.

Best regards,
Dr. Meriton

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