I have been having chest pains consistent with angina: chest 'compression', pain, following excretion, etc. but relieved through burping.  (After burping I am able to continue exercising without pain).  I had a stress test which went well and included reaching my 'gas pain' compression level (HP 150).  The EKG apparently was fine (I was told that I was in great shape by the test administrator).  But when the doctor later reviewed the pictures he saw a lack of blood - and hence angina - in the lower part of my heart (an 'atypical presentation').  He said that in 80 to 90 % of these case the symptoms are due to a internally blocked artery.  (The remaining % are caused by a problem in the 'gut' - I could not get him to give me an explanation of what that meant).   In any case, I'm scheduled for a cauterization, and if appropriate a stint insertion.  I believe that it might be that the buildup of gas may have caused an 'external' compression of the artery but I have been unable to find any collaboration that this could occur.