the feelings of being dissociated from the world is classic of panic attacks.. Yes, palpitations for me feel similar to what you describe... It sounds as if you where on a monitor while you where symptomatic? If so, this should be reassuring..
hope this helps!
Holter didn't catch anything to serious, but telemetry and ECHO 3 lead caught a ton of sensations. I guess since no alarms went off or doctor came rushing in, that it wasn't too serious.
It's good that you have been on a monitoring device while you had symptoms, that should offer some peace of mind.
As for the symptoms you describe, yes. Many of my PACs feel just like that. Mostly, when I am more anxious than usual.