@nfsandf Aah! So, for many/most who develop AF, their ventricles try to 'keep up' with the signals coming from the AV node, which is picking up on the spurious signals causing the left atrium to beat rapidly. When the ventricle is keeping up by beating rapidly, it is formally known as 'rapid ventricular response' or RVR. You don't have that....I'm guessing by your choice of words just above...or your cardiologist's. So, it is sometimes the case that there IS AF, but the left ventricle continues to beat at a reasonable 50-75 beats a minute...ish. For me, and for others like me, my HR was always well above 120 BPM, sometimes as high as 180, which made the electrophysiologist looking at my case blanch and immediately raise my Rx for metoprolol from 25 mg BID to 50. 🙁