Objectives Disease activity has emerged as a new, independent risk factor for cardiovascular disease in patients with rheumatoid arthritis (RA). We tested if disease activity in RA was associated with lower left ventricular (LV) systolic function independent of traditional cardiovascular risk factors.

Methods Echocardiographic assessment was performed in 78 patients with RA having low, moderate or high disease activity (Simplified Disease Activity Index (SDAI) >3.3), 41 patients in remission (SDAI ≤3.3) and 46 controls, all without known cardiac disease. LV systolic function was assessed by biplane Simpson ejection fraction, stress-corrected midwall shortening (scMWS) and global longitudinal strain (GLS).

Results Patients with active RA had higher prevalence of hypertension and diabetes compared with patients in remission and controls (both p<0.05). LV ejection fraction (endocardial function) was normal in all three groups, while mean scMWS and GLS (myocardial function) were reduced in patients with RA with active disease compared with patients with RA in remission (95±18% vs 105±17% and −18.9±3.1% vs −20.6±3.5%, respectively, both p<0.01). Patients with RA in remission had similar scMWS and GLS as the controls. In multivariable analyses, having active RA was associated with lower GLS (β=0.21) and scMWS (β=−0.22, both p<0.05), both reflecting lower LV systolic myocardial function, independent of cardiovascular risk factors and LV ejection fraction. Classification of RA disease activity by other disease activity composite scores yielded similar results.

Conclusions Active RA is associated with lower LV systolic myocardial function despite normal ejection fraction and independent of traditional cardiovascular risk factors.