I did experience slight heart poundings during the beginning of my pcs. I would be sleeping then all of a sudden I would wake up out of nowhere with my heart pounding really fast and breathing heavily. I would just to try calm myself down and eventually just go back to sleep. I was taking xanex at the time but only when needed. I tried not to take medications, instead I did Tai Chi Qigong Shabshi to focus on my breathing, calming my mind, and my panic attacks. If you look on youtube you can find some videos on how to do the 18moves, you can also put on relaxing music along with doing these exercises as well.