Are there any medics out there who can help me understand what is happening. Kept in hospital (3rd time in a month) for normal attack of atrial fibrillation - heart beat 129 (normal rate 50); pain in jaw (lack of oxygen), low potassium. Given oxygen and potassium. Monitored remotely all night. Doctor then said my Afib is changing - now in clusters and will be more frequent. Discovered I had been in sinus rhythm all night - regular beats of 119 slowing down. In the morning Consultant said I had angina - this has been queried before.. Does heart beat increase this much with angina? Can Afib be regular? How can I play table tennis for 1 1/2 hours with no effect and walk my dog for 45 minutes ditto? Awaiting nuclear scan but will be at least another 6 months. Am at the high end of medication - beta blockers , anti-arrhythmic + warfarin so only beta blockers increased- now 5mg night and morning. I am an active 70 yr old. I have a GTN spray but never need to use it except when in A fib.