question: I m 29 and live a very active life style. I was diagnosed with mitro valve prolapse at the age of 18 and then with cardiac induced rhino conjustivitis at 23. I m now on high blood pressure medication and I like to take B12 because it helps with hangovers on the weekend and makes me feel awake in the morning without drinking coffee. Lately when I run a begin to have a sharp pain in the center of my chest on the left side. I can t tell if it s my heart or lungs. Leaning forward causes an immediate sharp pain in the same area and short shallow breaths help to stop the pain from occuring when I inhale. I m 6 5, 200 lbs and perform a first class physical fitness test (PFT) (3 miles in 25 mins, 19 pull ups, 100 crunches in under a min) in the Marines. What gives? Should I be considering a new profession?