Question: 26 year old female, 185lbs but active. Every now and then I get a strong "flip-flop" sensation in the lower center of my chest. Typically it makes me cough, or clear my throat, and it's gone. Yesterday amidst some routine everyday outside activity, the "flip-flop" happened, I coughed, but it did not stop. I tried a stronger cough, but the strong "fluttering" kept on going. I pressed my fingers to my neck to check my pulse and could feel a fast, erratic beat with no real pattern. I began to panic and walked out to my car to get my phone, and after about 15 seconds, the sensation finally stopped. This is the longest it has ever happened and I am terrified. I've had several heart workups in the recent past for other issues but am always told even despite my weight, my heart is healthy due to my activity level. I have been an active horseback rider for many years, but put the weight on after breaking my hip a little over a year ago. I plan to get back in shape this year, but am now worried that any increase in activity will bring another one of these "episodes" on in greater length. Can anyone please tell me what is happening to me? I have never been so afraid. Thank you.