Hello, I am 27yrs old female, I first experienced palpitations in 1998 when I was asked to run. I fell my chest get heavy and then my heart beat faster and I had to stop and catch my breath. Since then I ve experience palpitations, skip beat and sharp pain in d chest over time under diverse conditions. I have observed that any of these occurrence have happened under exposure to cold , extreme heat or when ever I feel stressed either from standing for too long, having to climb the stairs at a fast pace or when I run. Often I get breathless after a long work( a walk of 45mins and above). At times for no particular reason I just feel my heart beat sharply like twice (which is painful) and then my breathing will cease briefly like 2-3secs and I get breathless; this particular experience I have noticed occurred just immediately as I suddenly move my left hand . Twice to punch a friend and once I wanted to scoop water. Always whenever I feel the sharp heart beat and get breathless I become very weak and unable to support my weight. Medicals so far: Between 1998 till now I have done 4 ECG test, 1 Holter ECG test, 5 echo test, 1 2D doppler echo, 1 X-ray , 1 chemistry test. But despite these test nothing has been diagnosed cardio wise. please what other test do i need to do get this problem properly diagnosed?