The aim of this study was to evaluate atrial electromechanical delay measured by tissue Doppler imaging (TDI) and left atrial (LA) mechanical functions in patients with rheumatoid arthritis (RA).
The study included 68 patients (53 females, 15 males; mean age 43.7 years) with RA. Using TDI, atrial electromechanical coupling (PA) was measured from the lateral mitral annulus (PA lateral), septal mitral annulus (PA septum), and right ventricular tricuspid annulus (PA tricuspid). Left atrial volumes (maximal, minimal, and pre-systolic) were measured by the method of discs in the apical four-chamber view and were indexed to body surface area. Mechanical function parameters of the LA were calculated. The results were compared with those of 41 age- and gender-matched healthy volunteers (32 females, 9 males; mean age 41.9 years).
Patients with RA had significantly prolonged PA lateral, PA septum, and intra- (PA septum-PA tricuspid) and interatrial (PA lateral-PA tricuspid) electromechanical delays compared to controls (p<0.0001, p=0.05, p<0.0001, and p<0.0001, respectively). Left atrial volumes were similar in the two groups (p>0.05). Left atrial passive emptying fraction was significantly decreased, LA active emptying volume and active emptying fraction were increased in RA patients (p=0.05, p=0.01, and p<0.0001; respectively). Interatrial electromechanical delay was correlated with systolic blood pressure (r=0.20, p=0.04), left ventricular mass index (r=0.22, p=0.02), C-reactive protein (CRP) (r=0.27, p=0.005), and LA active emptying fraction (r=0.29, p=0.002). In linear regression analysis, LA active emptying fraction and CRP were independent variables of interatrial electromechanical delay (beta=0.28, p=0.002 and beta=0.25, p=0.006, respectively).
Prolonged electromechanical delays and impaired LA mechanical functions may be an early manifestation of subclinical cardiac involvement in RA patients.