I did a post with link but moderator has to ok that. But it is important to know that BIOTIN in your vitamins or supplements will cause a false negative TROPONIN if it was taken within 12 hours of test. So any heart patients are advised to check you vitamins and supplements and do not take them if they have biotin. My cardiac is reviewing all my records and ct of heart because highly likely we have missing heart attacks. I do have ones where I did have MI or raised troponins because test was taken after 12 hours taking them but others indicated MI on ECG and I had taken biotin with in just a couple ours in vitamins.