Correlation between Left Atrial Thrombosis and Neutrophil-to-Lymphocyte Ratio upon Non-Valvular Atrial Fibrillation

Background: To explore the correlation between left atrial thrombosis and peripheral blood neutrophil-to-lymphocyte ratio (NLR) in patients with non-valvular atrial fibrillation (NVAF). Methods: A total of 207 NVAF patients treated from March 2016 to August 2020 were divided into low and high NLR groups. Their clinical data were compared, and the correlations of NLR with clinical indicators and left atrial thrombosis were analyzed. The influencing factors for left atrial thrombosis and their predictive values were investigated. Results: CHADS(2) score, CHA(2)DS(2)-VASc score, NLR, D-dimer (D-D), serum uric acid (SUA), brain natriuretic peptide (BNP), C-reactive protein (CRP), left atrial dimension (LAD) and ratio of early mitral diastolic flow peak value to early diastolic mitral annular velocity (E/Em) increased, while left atrial ejection fraction (LAEF) decreased in high NLR group compared with those in low NLR group (p < 0.05). NLR was significantly positively correlated with the CHADS(2) score, CHA(2)DS(2)-VASc score, D-D, SUA, BNP, CRP, LAD and E/Em, and significantly negatively correlated with LAEF (p < 0.0001). Left atrial thrombosis had positive correlations with CHADS(2) score, CHA(2)DS(2)-VASc score, NLR, D-D, SUA, BNP, CRP, LAD and E/Em, and negative correlation with LAEF (p = 0.000). CHA(2)DS(2)-VASc score, NLR, D-D and LAD were risk factors for left atrial thrombosis ( p < 0.05). The optimal cut-off value was 1.85 when the area under the curve of NLR for predicting left atrial thrombosis in the case of NVAF was 0.806 [95% confidence interval (CI): 0.746 - 0.865], the sensitivity was 74.82% (95% CI: 0.668 - 0.818) and the specificity was 67.65% (95% CI: 0.552 - 0.785). Conclusions: The increase of NLR prominently elevates the risk of left atrial thrombosis in NVAF patients, and NLR was an independent risk factor, with certain predictive value.