[Guest]

On occasion, I feel sharp, stabbing pains deep in the left side of my chest. It seems to worsen on the exhale. It can last from a few seconds to a couple of hours. The strange thing is that I'll get a popping sensation in my chest and sometimes I can actually hear it, and then the pain goes away. I've been to a cardiologist and have been given both a stress and resting echocardiogram. I just had one done last month. I also suffer from palpitations. The doctor found no abnormalities. I had two recent episodes: 1. Two days ago at about 5:30 a.m. when I was sleeping, and 2. Just this morning at about the same time. This morning's pain was three consecutive pains and "pops" and it was gone. No other symptoms except for some brief mild pain in the back and a little in my left arm, and of course some feelings of panic (which I'm prone to) because it scared me. I'm otherwise a healthy, 100 pound, 38 year old woman, but I take Zocor for high cholesterol (199). I don't think the Zocor is responsible as I've been getting these sensations since I've been about 19 years old and didn't start the meds until recently. Any suggestions? Thank you.