That doesn't surprise me after my experience. At one stage a consultant insisted that my cholesterol was too high at 7—later that day a registrar apologised and said it was actually, 3.9. At one stage, I was told my treadmill test was inconclusive because I was still taking beta-blockers (I've never taken beta-blockers). And, on discharge, I was told to stop taking all of my prescribed heart medication, but that I should continue taking my Losec prescription. That was a surprise, as I wasn't taking taking and hadn't been prescribed either heart medication or Losec.
I think the problem is one of pigeon-holing, as Mintzberg would say. Because I didn't fit neatly into a standard pigeon-hole (not a heart attack, not angina) they weren't quite sure what to do with me, or who'd be responsible. So, the default came into play—back to the GP. Actually, I have the impression that the whole of the "High Dependency Unit' exists mainly as a holding pen whilst patients are categorise (pigeon-holed) before being dispatched to the"correct' location, e.g., The cardio ward, Gastroenterology, etc.