Thanks for using the forum. I am happy to address your questions, and my answer will be based on the information you provided here. Please make sure you recognize that this forum is for educational purposes only, and it does not substitute for a formal office visit with a doctor.
Without the ability to examine and obtain a history, I can not tell you what the exact cause of the symptoms is. However I will try to provide you with some useful information.
Local back pain, as you are describing, is usually a result of irritation of or damage to structures of the spine (e.g., periosteum, ligament, dura, and joints). The pain is usually exacerbated by activities that cause these structures to have increased pressure load (e.g., prolonged sitting or walking up steps). Prolonged irritation of these joints can cause muscle spasm described as a diffuse, burning pain. Given your history of rheumatoid arthritis, I would favor a facet joint pain, if prior workup has been negative and no history of trauma to this area of your back, with muscular involvement.
X-rays of the back may show chronic degenerative changes of the bones. An MRI of the thoracic spine, is usually not indicated if no neurological deficits, but it may be helpful to evaluate for more unusual causes of local back pain such as an epidural tumor or syrinx.
Treatment of these types of pains includes NSAIDs and physical therapy. If no improvement with these, a pain specialist may opt to do a procedure called facet joint block.
It is difficult to say a local back pain would cause shortness of breath. Was your cardiac catheterization completely normal? Was there no indication for the various types of angina (stable, unstable, pinzmetal)? Have you had a stress test? Have you had an EGD to evaluate your esophagus and stomach? Have you had a CT of the chest to rule out pulmonary causes?
You should follow up with your PCP. If your other workup (for heart, pulmonary, and GI causes) was complete and normal, a referral to physical therapy would be recommended. Again, I would continue to explore your symptoms further with cardiology, gastroenterology, and pulmonology to rule out other causes for shortness of breath.
Thank you for this opportunity to answer your questions, I hope you find the information I have provided useful, good luck.
I have had EKG, Barium Swallow, Gastroscopy( showed gastritis & hiatal hernia), colonoscopy, echo-cardiogram, cardiac cath was clear, no signs of any blockage. Arteries were larger than normal ( I have had high blood pressure for years) I had a nuclear stress test of the heart which was also normal. The Doctor decided to go ahead with the cardiac cath due to the possibility of a false normal. I have been on Celebrex, prednisone, plaquinal, methatrexate, enberol, folic acid, fosamax. I stopped celebrex and prednisone for one month, joint pain became worse, I am on Nexium for the gastritis. I have been healthy except for the rheumatoid arthritis. This burning pain and shortness of breath is getting me down. I have always been very active, walk at least 2 miles a day, now I am lucky to go around the block. I appreciate your responding to my question.