I find this problem with af quite confusing.. My Heart and coronary arteries fine. Do not have heart failure but am now in af most of the time after two periods of several days in hospital with racing heart they had difficulty in bringing down. Pace maker regulating this now. I have a hemi block left ventricle of heart causing delay in signal to heart . Am waiting for urgent ablation for this. At the moment it feels that I come under the category of no further action other than just being treated mainly with meds like Bisoprolol that has caused my breathing to be so bad it has reduced me from being a fit active person walking three miles a day, gardening for hours, to someone who now needs blue badge, attendance allowance etc..