Symptoms....I feel a weird 'lightness' in my chest (I think heart) for just a few seconds....then I get light headed/dizzy and a mild headheache...these episodes happen maybe once or twice a day at most and I can go for three or four days without feeling them....I had a stress test...no problems found there.....my doctor dismisses it as stress and 'chest muscles' but I don't feel convinced....any help out there???