RESUMO
OBJECTIVES: Systemic lupus erythematosus (SLE) is an autoimmune disorder resulting in multisystemic inflammatory damage. Recent articles report that 20% to 30% of deaths in patients with SLE have cardiovascular origin. The aim of this study was to investigate the atrial conduction time in patients with SLE by using high-usefulness tissue Doppler echocardiography (TDI). METHODS: The study population included 56 patients with SLE (49 women; mean [SD] age, 46.2 [12.2] years, and mean [SD] disease duration, 30.7 [10.9] months) and 45 healthy subjects as control group (39 women; mean [SD] age, 45.8 [12.3] years). P-wave dispersion (PWD) was calculated by using 12-lead electrocardiogram. The timing of atrial contractions (PA) was measured as the interval between the onset of P wave on electrocardiogram and the beginning of A wave on TDI. Atrial electromechanical delay (EMD) was calculated from the lateral (PA lateral), septal (PA septal) mitral annulus, and lateral tricuspid annulus (PA tricuspid). RESULTS: Lateral mitral annulus and PA septal were significantly longer in the patients with SLE than in the control subjects (66.7 [15.9] vs 56.5 [13.7], P = 0.001, and 53.5 [15.0] vs 45.0 [15.1] milliseconds, P = 0.006, respectively). Interatrial (PA lateral - PA tricuspid) and intra-atrial (PA septal - PA tricuspid) EMD were significantly higher in SLE groups (25.5 [9.7] vs 19.9 [8.3], P = 0.003 and 13.3 [7.7] vs 8.4 [8.0] milliseconds, P = 0.002, respectively). Similarly, maximum P-wave duration and PWD were significantly longer in the patients with SLE than in the control subjects (104.9 [13.5] vs 98.1 [15.1], P = 0.021 and 24.6 [7.4] vs 20.0 [8.1] milliseconds, P = 0.004, respectively). There were significant positive correlations between the disease duration and interatrial EMD (r = 0.611, P < 0.001) and intra-atrial EMD (r = 0.565, P < 0.001). Positive correlation was also present between the disease duration and PWD (r = 0.457, P < 0.001). CONCLUSION: Atrial EMD is prolonged in patients with SLE. We have also shown that PWD, intra-atrial EMD, and interatrial EMD were significantly correlated with disease duration. This study calls attention to the following: the measurement of atrial conduction time may be clinically helpful in the definition of cardiac involvement.