Yes, I did have tests done. Multiple tests and blood tests. Initially, they thought it was my thyroid. I had ultrasounds and an upper GI X-ray. I had EKG which confirmed the heart palpitations. I wore a heart monitor for 24 hours, which did nothing, but confirm the consistency and frequency? My GP or the cardiologist couldn't explain the severe anxiety and racing heart beat. They both seem to be clueless about the Mirena. The cardiologist said he did an online search and couldn't find anything about the Mirena. All that did was raise a red flag for me. He did put me on betablockers and stated they should help with the heart palpitations. Also all test came out within normal. This totally contradicts the crap that I am still feeling.