Redknapp had an operation on Wednesday to have two stents inserted to unblock coronary arteries after he became ill while using a running machine at his home earlier in the week.
The 64-year-old missed Thursday's Europa League defeat at Rubin Kazan and Sunday's Premier League trip to Fulham as he started his rehabilitation.
Redknapp had previously talked of being away from the dugout for two weeks but admitted on Sunday that it could be longer before he is back in action.
"I have got to listen what the doctors tell me and not get too stressed out," he told Sky Sports News. "Stress is what causes most of the problems anyway.
"I will be fine, I have just got to take my time and when I am ready come back and get on with it but not before I get the go-ahead from the people in charge.
"They have said I shouldn't even think about football for four to five weeks and get myself stressed. I will see how I go but I hope to be back before then."
Source: AFP
Source: AFP