Five years ago I had a dilated left ventricle due to occluded coronary vessels. The
heart became overworked and
increased in size. Medication that reduced the heart's workload provided the time necessary to recover (about a year), and currently the heart is normal size.
If there is heart muscle is damaged (virus, alcohol, medication, congenital, etc.) , the outlook is not favorable and treatment would be to slow any progression, if any.