The doctor's opinion is that you have heart muscle damage (globally, rAther than a specific location). The ejection fraction (amount of blood pumped with each heartbeat) is normal at 50 to 70%, and with heart muscle damage that would explain the low EF of 25%.
Six years ago I had a left ventricle enlargement, and a silent heart attack (didn't know I had had a heart attack until congested heart failure) that caused my EF to be between 19 to 29% (below 29% is considered heart failure mode). There appeared to be heart muscle damage. Medication reduced the heart's workload and that help my heart return to normal size and the EF is now at 59%. Also, an increase of blood supply to the area of the damaged heart cells revived the heart cells (damaged heart cells can be necrotic (dead) or in hypernation..