I visited A & E last evening after what doctor feels to have been an episode of AF. However, once there, everything settled down and although pulse rate was still high nothing showed up on ECG. I have had minor episodes of symptoms before (not realising what they were) but this one was really scary and I thought I was dying!! I felt my heart stop and it seemed to do a somersault!! I have now been advised to go to GP and then on for referral to Cardio. Will a 24 hour ECG diagnose AF? Is there any other way of diagnosing it? I am concerned that if I don't have an episode in the 24 hour period I have the machine, no treatment will be given.