Objective: To determine the predictors of thrombosis in left atrium (LA) or left atrial appendage (LAA) in patients with nonvalvular atrial fibrillation.
Methods: Two hundred and eight patients under 65 year old with atrial fibrillation (AF) were included and all of them received examination of transesophageal echocardiography (TEE). Thrombus formation in LA/LAA was found in 23 patients (thrombus group) but absent in the remaining 185 patients (nonthrombus group). All patients were analyzed by univariate regression and binary logistic regression to investigate the relationship between the occurrence of LA/LAA thrombosis and these factors (such as case history, smoking/drinking preference, indicators of clinical blood examination and ultrasound imaging study, etc)
Results: Univariate analysis revealed that diameter of LA [(34.9 +/- 4.4) mm vs (42.2 +/- 6.5) mm, P = 0.000], ratio of chest and heart (60/185 vs 20/23 P = 0.000), brain infarction/transient ischemic attack (TAI) (7/185 vs 6/23 P = 0.000), smoking (30/185 vs 8/23, P = 0.030), fibrinogen (FIB) [(3.0 +/- 0.7)g/L vs (3.5 +/- 1.0) g/L, P = 0.000], coronary artery disease (CAD) (10/185 vs 6/23, P = 0.000) and LVDd [(45.7 +/- 4.1) mm vs (48.5 +/- 5.7) mm, P = 0.000] and LVEF [(65.1 +/- 6.6) mm vs (59.3 +/- 1.3) mm, P = 0.050] were significant between nonthrombus group and thrombus group (P < 0.05). However binary logistic regression analysis identified that only LAD, ratio of chest and heart, brain infarction/TAI and FIB were the significant and independent predictors of LA/LAA thrombosis.
Conclusion: Diameter of LA, ratio of chest and heart, brain infarction/TAI and FIB are independent risk factors of thrombosis in patients under 65 year old with nonvalvular atrial fibrillation. These patients need a better anticoagulation.