Feeling totally hopeless and nowhere to turn...
I have suffered from severe anxiety/agoraphobia now for almost ten years. I am also in no way a professional, but I will share something with you, and I would recommend talking to a Dr about this.
I do suffer from anxiety, but like you I was having these crazy things go on with my heart, it was scaring me so bad I was afraid to go to sleep. Finally I seen my OB GYN, and because I had a hysterectomy when I was in my 20's I had been on HRT (hormone replacement therapy) for years. They took me off the Depo Estradiol, and put me on Bio Identical hormones, and within hours it was gone. No more heart palpitations, none and the only time I feel them now is when I forget my hormone pill. I was amazed, truly amazed because I truly thought at any moment I was going to have a heart attack, and was very upset with my regular Dr that he could not see this.
For a couple of weeks I was so excited the palpitations were gone that my anxiety got better, but unfortunately something happened that triggered an attack, and right back to square one I went.
Good luck, and maybe that is something you could check on with your Dr. My heart truly goes out to you, because that is a scary feeling. Seems like there is a great group of people here for support. I have only been on here a few days, and so far extremely impressed with everyone, and this program!!