I had an EKG. I don't think it was abnormal but I was referred out for near syncope (in specific circumstances) where I got on the meds I am on. I could barely breathe off the plane when I had the severe respiratory problems. And I expect that earlier on, I just had a high pulse when flying. I would say that the near syncope when that happened was worst standing. And in addition to the oxygen, I "iced" to recover.