For the last few weeks, my heart has been racing almost daily, sometimes for hours. It's not the same as a full fledged panic attack like I usually have, but it is ferociously uncomfortable. I can't for the life of me figure out what is triggering it. I've had an ECG recently which was all clear, and I don't know if there's any point in seeing my doctor, who will just say it's probably PTSD. It's making it hard to get any work done, and next to impossible to exercise. Has anyone else experienced this? Does it ever go away? I'm so frustrated I could throw things.