My Father Had 1 Stent Put In A Couple Months

My father had 1 stent put in a couple months ago and complains that he feels that his heart is fluttering or throbbing when he exerts himself. He tends to notice this the most when golfing or doing work around the house. His HCP told him that he wanted to try him on metoprolol. How concerned at this time should we be?

Thanks,

Adam Smith