I was going to post in another thread with this title but it was closed? I had an MRI of the right shoulder today in an open MRI and went through about 6 cycles of scans (I think it was 6). During the 4th cycle I noticed that my heart rate was increasing. I went in to this with a calm demeanor and was very relaxed so I know it wasn't me getting nervous. Being a mountain bike racer I was able to calm the rate down some until the 4min was up. The last two cycles I was totally fine. What could cause this because I had this happen in the past for a low back MRI and I thought it was me getting claustrophobic but I really didn't feel that way.