Ejection fraction is the measure of the pumping ability of the heart. It is reduced if the patient has suffered heart attack and if there is lack of blood flow to the heart. Following a heart attack there is damage to the heart muscle and this is irreversible. However fall in ejection fraction due to lack of blood supply increases following bypass surgery. This is usually seen on echocardiogram done 3-4 months following surgery. Patients who have dysfunction of LV (low ejection fraction) need to be in follow up of their cardiologist for optimization of drugs. He should continue to his walks. I hope I have answered your queries but if you have any other doubts, please feel free to contact us & it shall be an pleasure to answer them.