For aim 1, the proposed studies will be performed in 150 patients with RA and 25 subjects without RA (healthy volunteers) who will function as controls.||For aim 2, 25 of the patients enrolled in aim 1 (who are in need for further treatment due to increased RA activity despite their current treatment) will be recruited to continue in the study for an additional 24 (+/- 2) weeks (or 6 months). These patient will receive a TNF inhibitor in addition to their current treatment in an open label protocol for increased disease activity and in the context of standard of care.||The investigators hypothesize that anti-TNF agents in RA patients without heart disease will not adversely affect the heart (will not cause a detrimental change in heart structure or its function).