I am a guy in my mid 40's. I have always been high anxiety but functional in society up until 10 years ago when I suffered my first panic attack. For the most part I am ok however about every three years my anxiety goes crazy to the point that I can't drive or leave the house. I am going through one of those times now and loosing lots of weight because I cant eat. One of the new problems I developed is sudden onset of high pulse. Don't get me wrong, I know panic attacks can raise your pulse, I am used to that. My new symptom is that my pulse is completely normal, shoots up to 160 bpm for no apparent reason, stays at that for 5 to 10 minutes then returns back to normal just as quickly as it started. Its just bam. high heart rate and bam normal heart rate. During this time I just lay on the ground and attempt to get my breathing correct. Sometimes it hit me when I am not even anxious. I have had a halter monitor done and the doctor said I have sinus tachycardia. The problem is that I had no symptoms of what I am concerned about and I know my pulse was high during the test because I forced myself to go to work, so yeah I agree with what the doctor had seen. Anyways I could use some help. Does anybody else suffer from sudden onset and sudden return to normal pulse? I normally get high resting pulse about 130 or so that slowly returns to normal as the adrenalin get burned off over time. This all started a few months ago when I collapsed on my everyday 3 mile walk. I have not been able to return to normal exercise as I am always out of breath.