So, I have pretty severe anxiety. About a year ago, I was getting day long panic attacks with dissociation and a pounding heartbeat that left me convinced I was dying. I got two EKGs and they were both normal, no further testing done. I got my antidepressants dosage upped, and after a bit, things started to settle down. 
I'm a lot better now, however, I still get bad sometimes. However, something I'm currently concerned about is the fact that I get heart palpitations like every day. They're super brief, but concerning and happen even when I'm not anxious. Does that happen to anyone else?
And if it does, does it kind of feel like someone is squeezing your heart like a sponge? Weird analogy but all I could think of. It's not painful at all, just more startling, and lasts a literal second. I just want to know if fellow anxiety sufferers experience anything similar.