Background: This study was conducted to investigate factors associated with stroke in pa-tients with paroxysmal atrial fibrillation (PAF) beyond CHADS2 score in terms of left ventricular (LV) diastolic function or left atrial (LA) function.
Methods: One hundred and sixty-one patients with PAF and age less than 75 (mean age 61 ± 10; 69 male) who underwent transthoracic echocardiography were investigated. Patients were divided into two groups according to the stroke status (group 1 - no stroke vs. group 2 - presence of stroke). Baseline echocardiographic parameters and LA segmental (4 segments: basal septal, lateral, inferior, and anterior) strain rate (SR) during normal sinus rhythm were analyzed.
Results: CHAD score (except S2) was similar between the two groups (0.6 ± 0.7 vs. 0.9 ± 0.7, p = 0.125). Patients with stroke had slightly lower body mass index (24.5 ± 2.7 vs. 23.4 ± ± 2.4, p = 0.052). Echocardiographic parameters did not show any differences in both systolic and diastolic functions between the two groups, however elevated E/E' ratio was noted (9.5 ± ± 3.8 vs. 11.6 ± 3.9, p = 0.010) due to higher E velocity (63.5 ± 15.9 vs. 70.9 ± 16.0 cm/s, p = 0.046). In the analysis of LA SR, there are no differences of SR among the 4 segments. However, standard deviations (SD) of time to peak SR (SD of tA-SR) of the 4 segments were higher in patients with stroke (10.9 ± 9.9 vs. 22.1 ± 18.1 ms, p = 0.009) which indicates dyssynchronous contraction of LA. In multivariate analysis, SD of tA-SR (OR 1.074, CI 1.024-1.128, p = 0.004) and elevated E/E' (OR 1.189, CI 1.006-1.406, p = 0.048) were independently associated with stroke in patients with PAF.
Conclusions: Elevated E velocity, E/E' and SD of tA-SR were associated with occurrence of stroke in patients with PAF even with similar CHAD scores. Increased SD of tA-SR and E/E' were independently associated with stroke in patients with PAF. (.
Keywords: left atrium; paroxysmal atrial fibrillation; strain rate; stroke.