Hello! Welcome and thank you for asking on HCM! Regarding your concern, I would explain that this test is quite safe. It can be associated so some rare adverse effects like : cardiac arrhythmia, allergic reaction, heart attack or chest pain, but they have been observed in a very low percent of patients who go through this test. There is no accumulation of the substances in your body after repeated tests. So, there is no risk of accumulation after some years. I would recommend repeating cardiac stress test every year, instead of this test , because it is less invasive and you do not need any injections. Only if suspicions are raised in cardiac stress tests, nuclear stress test should be done. Hope you will find this answer helpful! Kind regards, Dr. Iliri