Fire-munki - the Army medical criteria is crap. The people who access you have little common sense and will at a whim crush your chances of joining. I was diagnosed with a heart murmur at a young age. Never told the Army about it. Went for a medical with the RAF, passed. Got a grip of myself and decided to go for the Infantry instead

and had another medical, this time by different staff. Passed it again. Then went for another one because I decided to do things properly and go Airborne and had another medical (on my 3rd now) and failed. Had a heart murmur, oh no!! They never checked my NHS history and so off I went to get a full investigation and obviously passed it fine and was finally allowed to continue with my selection process.
What I am saying is, if you are confident enough, don't tell them about it!!!!