@foundryrat743 If you feel distinctly unwell and know for a fact that you have an arrythmia of any description, you should indeed call 911. The reason is that you may also be having a stroke (remember that five-times higher risk of a stroke due to dislodged clots from the left atrial appendage (LAA) when fibrillating. You DO NOT want a stroke....ever. They can leave you alive and in a wheelchair or abed until you die. Also left uncommunicative, unable to speak or even to write out what you need others to respond to on your behalf.

The rule of thumb is that if you have been fibrillating for more than 24 hours you should be taking an anti-coagulant. Also, if your measured heart rate (HR) is above 100 BPM for more than 24 hours, you should go to an ER. The reason is that such a high rate signifies what is called 'rapid ventricular response' (RVR), meaning your ventricles are beating just as fast and they should not be kept at that rate indefinitely, especially above 150 BPM. It's not so bad if only your left atrium is fibrillating, and yes, it WILL NOT kill you. People live with permanent AF all the time...if not terribly calmly or comfortably. But your ventricles cannot stand the same high rate indefinitely, so you need to get help if your measured rate stays above 100 BPM for more than 24 hours.