I am sorry that you are having such a difficult time. You mentioned that you had been to a cardiologist and all is fine, but have you been to a gastro doc? You also mentioned you are trying to get off the PPI's... I was wondering if they had been helping at all or not. In my case, my GERD was under control for a long time, but recently has gotten really bad again. I can relate with most of the symptoms you mentioned. I also suffer from anxiety disorder. (We have a great anxiety forum here too... you should drop by there!) I just wanted you to know that you are not alone with this. Right now I'm not having much luck managing my symptoms, and I'm on 3 different meds.
"It's a jungle out there....."
Theme song from "Monk" by Randy Newman
"Turn this car around... I'm goin' back..."