Relationship of inflammatory indices with left atrial appendage thrombus or spontaneous echo contrast in patients with atrial fibrillation.

Background: Inflammatory indices derived from complete blood tests have been reported to be associated with poor outcomes in patients with atrial fibrillation (AF). The data about the relationship between inflammatory indices and left atrial appendage thrombus (LAAT) or dense spontaneous echo contrast (SEC) are limited.

Aim: To explore the value of inflammatory indices for predicting the presence of LAAT or dense SEC in nonvalvular AF patients.

Methods: A total of 406 patients with nonvalvular AF who underwent transesophageal echocardiography were included and divided into two groups based on the presence (study group) or absence (control group) of LAAT or dense SEC. Inflammatory indices, including the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and lymphocyte-to-monocyte ratio (LMR), were calculated from complete blood analysis. The associations of inflammatory indices with LAAT/dense SEC were analyzed using logistic regression.

Results: LAAT and dense SEC were detected in 11 (2.7%) and 42 (10.3%) patients, respectively. The PLR only showed an association with LAAT/dense SEC in the univariate model. Elevated NLR (odds ratio [OR] = 1.48, 95% confidence interval [CI]: 1.11-1.98, = 0.007) and reduced LMR (OR = 0.59, 95%CI: 0.41-0.83, = 0.003) were found to be independent risk factors for the presence of LAAT/dense SEC. The areas under the NLR and LMR curves for predicting LAAT/dense SEC were 0.73 (95%CI: 0.66-0.80, < 0.001) and 0.73 (95%CI: 0.65-0.81, < 0.001), respectively, while the cutoff values were 2.8 (sensitivity: 69.8%; specificity: 64.0%) and 2.4 (sensitivity: 71.7%; specificity: 60.6%), respectively.

Conclusion: Increased NLR and decreased LMR may predict LAAT/dense SEC in patients with nonvalvular AF.