Joline,
Thanks for the post.
I've not heard of someone having poor healing from taking atenolol, but I suppose it is possible. A more likely reason for poor healing is diabetes, if you have that condition.
If you do not have a history of heart disease, then it is generally fine to stop the atenolol. If, on the other hand, you have a history of coronary artery disease, then stopping the atenolol abruptly might not be the best idea.
One method of tapering the atenolol would be to take half the dose for three days, then stop.
Hope that helps.