Burning sensation in chest

I was just recently discharged from the hospital after testing negative for cardio issues.  I am having a burning sensation in my strenum that only occurs during exertion.  I had a stress test, nuclear photos, and the whole 9 yards of tests.  During the stress test I told my doctor that the burning was increasing as we progressed.  Yet they could find no signs of trouble. I have been out for 2 days and still experiencing same symptoms.  They started me on Nexium but I am not seeing much of a change.  I have cardio issues - 2 years ago I had heart cath and 2 stents were placed in my heart at that time.  What should I do? I feel foolish checking into the er again.

[Ruthiebear]

So sorry you are experiencing your pain.  You sound like your on top of whatever is going on.    I too have burning and had a stint put in this last Oct. 2008.  I don't know why you are having this burning just found it interesting that I have this problem but in a different area under my underarm as well my chest.
Going to the ER is ok better safe then sorry. I kind of feel like you about going though, but everyone around me tells me I should go to the ER when my pain gets very bad.  
I'm also just started coming here looking for answers myself.
I am interested also in what you said they didn't find anything while in the ER what it just blood work this time?  
Ruth