Thank you for your question,
I am fellow expert in cardiology and will try to help you out.
shows low ejection fraction
of heart function after heart attack
due to stunning of the heart muscles.
After successful angioplasty
there are high chances that his heart function will improve.
So echo after 3 weeks is likely to show better heart function.
He needs to continue his heart medicine.
regaining of 100% heart function is not possible after most of the heart attacks as some area of the heart is always damaged.
I hope this helps..
Let me know if you have more questions.