Dear patient, Thanks for your health concerns. The presence of right thorax pain with visible swelling makes a heart problem as a cause significantly less likely, but I would advise to continue to seek medical attention to reach a specific diagnosis, for example rotator cuff tear, bursitis, septic arthritis, an abscess, etc; an orthopedic surgeon likely is the most qualified to assess this shoulder pain and swelling. Hope this is useful, wish you the best health, Dr Brenes Salazar MD Mayo Clinic RST