I have had several episodes too at night. I wake up to my heart pounding so hard and I have to go outside for air. It's not healthy and I asked a doctor and she said it's probably anxiety, however I need to get an EKG to make sure nothing is wrong with my heart. She also recommended talking to a BHC (Behavioral Health Consultant) to further evaluate what is happening and what may be causing it. I know I have been stressed out with money, and worried. It may be the problem, but I need to go in and get checked.