Sarah -
I'm with you. My first three full-bore panic attacks put me in ER each time.
Since my Mom died of heart disease at age 68 and everyone has all but gone out of their way to tell me "that puts you at risk", I am convinced that every skipped heartbeat I can feel is the one that will take me out of the game.
My cardiologist put it in perspective when he told me that 30% of folks that come see him have this and the episodes are always survivable... in fact, he summarized it "You'll die [i]with[/i] it, not [i]from[/i] it."
Once the Lexapro took hold and the docs weaned me off the daily Xanax, the realization came true that I am NOT going to die from the episodes, and that if one is coming on, I am able to ride it out. Granted, I have this condition to a lesser degree than many others here, but that doesn't make it any less terrifying when I experience it.
Just know that you can ride it out too, and you're going to be living well for a good long time, hopefully like many of us here. Be strong.
V.