I have the same problem. I have anxiety and AF causing abnormal/fast heart beats, PVCs and adrenal rushes. I take a beta blocker for the fast heart rate and adrenaline rushes, but it doesn't help at night. The only thing that helped me was magnesium taurate from Cardiovascular Research. It stopped those weird surges that happen as you dose. I buy it from Amazon or Vitamin Shoppe. I ran out the other week and decided to use up my CALM magnesium Citrate, which helps some, but not like the mg taurate. My weird surges came back in full swing. Two days after taking three pills a day of the mg taurate, stopped my adrenaline surges at night. Also, hypoglycemia with AF can cause adrenaline spikes. Try some fat and protein before bed to see if that also helps. Atenolol beta blocker also helps with anxiety. I take about 6 mg at night since SSRIs give me anxiety! Good luck! Please post if you find something at helps. Linde :)