I have thousands of PVCs a day and I'm still here. Sometimes, when I get into a pattern, like every other beat is a PVC, it can feel like a constant flutter. It's quite annoying and anxiety provoking, but the more you concentrate on it, the worse it's going to get. I have found that if I go about my business and try to ignore them, I am much better off.
Treat the root cause. You are focused on symptoms. If the PVCs haven't killed you by now they won't. I can sit here all day and explain what they are and how they happen and why they're harmless but that won't help with your anxiety/panic disorder. Don't mean to sound harsh. Been through it myself.
The root cause is the anxiety and panic disorder. Get that under control and the symptoms will fade. Best to seek out professional help, I did cognitive behavioral therapy.