Dear friend, welcome to HCM !
It is definitely normal, after 3-4 months post-surgery.
It indicates either heart failure
or ongoing ischaemia- blood supply inadequacy.
Does he have swelling over the feet/ ankles?
Since how long is the tightness there?
Did he have fever
Is there any pus / wetness at the wounds?
He needs to be evaluated with a physical, Xray chest, an EKG(ECG).
Can go to the ER or your cardiologist early.
Take care and please keep me informed of your progress.
Good Luck !
I hope to have answered your query satisfactorily.
May I request for your rating and review of this answer before you accept the answer and close the query (if there are no more follow up questions)?
Thank you !