Risk factors of left atrial appendage thrombus in patients with non-valvular atrial fibrillation.

Objective: To investigate the risk factors of left atrial appendage thrombus (LAAT) in patients with non-valvular atrial fibrillation (AF).

Methods: We collected the clinical data of patients with non-valvular AF who underwent transesophageal echocardiography (TEE) at the Zhongda Hospital of Southeast University between January 2016 and June 2019. The patients were divided into two groups, LAAT and non-LAAT. We performed comparative analysis, receiver operating characteristic (ROC) curve analysis and logistic regression analysis to estimate the risk factors of LAAT.

Results: A total of 442 patients with non-valvular AF were enrolled in the study. LAAT was detected by TEE in 20 cases (4.7%). Compared with patients without LAAT, patients with LAAT had higher CHADS-VASc scores (3 vs 2, = 0.001), higher values of D-dimer (180.0 vs 90.0 μg/L, = 0.003), larger LA anteroposterior diameters (50.5 vs 41.0 mm, < 0.001) and higher ratios of non-paroxysmal AF (85.0% vs 23.6%, < 0.001). ROC curve analysis revealed that the cutoff value of LA anteroposterior diameter was 49.5 mm. After adjusting for other confounders, logistic regression analysis showed that enlarged LA (anteroposterior diameter ≥49.5 mm) and non-paroxysmal AF were independently associated with higher risks of LAAT (OR = 7.28, 95% CI: 2.36-22.47; OR = 8.89, 95% CI: 2.33-33.99, respectively). The proportions of LAAT in patients with larger LA (anteroposterior diameter ≥49.5 mm), non-paroxysmal AF and both larger LA and non-paroxysmal AF were 30% (12/40), 15.2% (17/112) and 39.1% (9/23), respectively.

Conclusion: Enlarged LA (anteroposterior diameter ≥49.5 mm) and non-paroxysmal AF were independent risk factors of LAAT in non-valvular AF patients.