I am a female 58 years of age, I'm fit and thin but lately I've been feeling sudden spams on my chest, they do not last long at all but it happens every now and then. I experienced the same thing last year and so I went to see a cardiologist, they took many test, I even had a 24 hour monitor on me so the doctor can see if their was any activity during that time. The doctor told me I'm healthy. What can this be? It's not painful, I do not get out of breath, it's just scary to me. Thanks!