No I haven't had this so no personal experience. However much like a 24hr BP monitor - the sooner everyone finds out that any of us have something not right with us - the sooner we can get it sorted out.
It's clear to you and the forum from your symptoms that you aren't right - and Oh look - the medics agree you're not - so don't fear them discovering how to treat it !
I don't think you'll notice it's there (although it will be odd I expect) cos I don't think they actually do anything noticeable (not like a BP machine pumping an arm up every so often and waking you up) when they're in use - just record your heartbeat in a way that can distinguish normal beat, beat, beat from 'slosh, slosh, beat' etc which isn't.
Anything on the British Heart Foundation website ? - or if not try ringing the hospital and asking to speak to a Cardiac Nurse - they're like DSNs for cardiac conditions - I see one re my PAD and she's good ! I'm sure they'll be able to set your mind at rest.
In the finish I hope it's something really easily treated.