t available at 137 mcg), and began experiencing atrial fibrillation 6 years ago. Sometimes TSH was within the
guidelines, sometimes above, sometimes below. I also take coumadin daily because I had an artificial mitral valve installed over ten years ago to replace a defective valve due to rheumatic heart disease. Heart rate runs between 75 and 160. On calcium channel blocker, the heart rate is now 70 - 90, but it goes up to 120 with stress or physical exertion.