It is good that you have seen a cardiologist and gotten a clean bill of health. Twice I had what I was sure were heart attacks, same symptoms as you described and in both cases I felt that I was dying, once I called ems to the side of the interstate, and once my terrified wife drove me to the ER, both times I had clean EKG s, People told me they sounded like panic attacks, to which I was sure they were full of shit because how could something that had such strong physical symptoms be just in my head, right?? Since then, about 5 months ago, I have accepted that I have anxiety/panic disorder, and I have seen a behavioral therapist and am now taking Lexapro 20mg everyday, I have gone from having about one level 10 (heart attack-like) panic attack/day to zero bad panic attacks and about 1-2 level 3 anxiety spells/week The good news is that the success rate for treatment of anxiety disorder is about the highest of any mental health disorder.--I am down to one session a week with the behavioral therapist, but there is no way I m quitting the Lexapro anytime soon. Drugs: SSRI s like Lexapro are now the gold standard, they used to give people benzodiazapenes like Xanax, now these are reserved for severe cases that don t respond to the SSRI s because they can cause dependance and they mellow you out almost too much to where they alter your personality. However SSRI s take a while to start working all the way, the smart thing is to start at 5mg, then 10, 15 up to 20, spending at least a couple days or more at each step, also they will fool with your serotonin levels and you feel something happening, some people report feeling a little worse the first day or two when they first start or tritate up to the next dose. I d ask your GP or a psychiatrist to see if maybe he d give you just a few Xanax as a stop gap, and start an SSRI, combine this with some behavioral therapy and you are going to start feeling a lot better really soon. Good luck!!! Also any good bookstores will have books on anxiety disorder, just make sure it is one written from a psychiatric/behavioral psychology perspective and not heal yourself with herbs, Jesus, Scientology, etc. Also, Google: Panic + Breathing Exercises ----This is something you can do to start feeling better right away!!!