Steve, Sorry to hear you’re having a hard time. Actually, I believe many of us with Graves have some heart envolvement and often a racing heart, palpitations etc. are how we first know that something is not right. I actually saw a cardiologist first because I had such bad tachycardia (rapid heart beat). It was so fast that I had actually developed a heart mummur apparently from the blood rushing so fast through the valves. This all quieted down after about two months post RAI treatment. I think the complicating factor with heart syptoms is that when you experience them they are often combined with your anxiety which makes it worse, of course. Anyway, hope this helps. Hang in there.
Liz