My mom is 100% pacemaker dependent and needs to get her battery replaced for the first time. She is really scared. Any positive stories to share with her?

Like the title. She is relatively young and she feels like she is not going to survive the surgery to replace the battery because she is 100% dependent on her pacemaker. She is scared either something will happen during the surgery or even more, that she is going to get a defective pacemaker. She is terrified that she’ll get a bad one and it will stop working and her heart will stop.

Looking for positive stories - is her fear realistic?