Analysis Of Risk Factors For Left Atrial Appendage Thrombosis Among Patients With Non-valvular Atrial Fibrillation

Objective:This paper aims to explore the independent risk factors for left atrial appendage thrombosis in patients with non-valvular atrial fibrillation through the analysis of laboratory test indicators and echocardiography results,analyze its predictive value for left atrial appendage thrombosis,and construct a new thromboembolism score scale based on the prediction results.Methods:Two hundred twenty-one patients with non-valvular atrial fibrillation who underwent transesophageal echocardiography examination in the Department of Cardiology of Linfen People’s Hospital from January 2018 to April 2022 were enrolled.According to the results of transesophageal echocardiography,all patients were divided into a thrombosis group（43 cases）and a non-thrombotic group（178cases）;the general clinical data,laboratory tests and echocardiography results of the two groups were compared using chi-square test and nonparametric test,the independent risk factors for left atrial appendage thrombosis in patients with non-valvular atrial fibrillation were analyzed by binary logistic regression,and the predictive value of independent risk factors was analyzed by Med Calc software.The index with high predictive value was included in the CHA₂DS₂-VASc scoring scale,a new thromboembolism prediction scale was constructed,and the working characteristic curve and area under the curve of subjects on the new rating scale and the CHA₂DS₂-VASc scoring scale were analyzed respectively,and the predicted value of the two rating scales was compared.Results:Two hundred twenty-one patients were included in this study,including 178cases in the thrombotic group and 43 cases in the non-thrombotic group.Univariate logistic regression analysis showed that there were statistically significant differences in age,stroke history,heart failure history,type of atrial fibrillation（persistent/paroxysmal）,lymphocytes,CHA₂DS₂-VASc score,left atrial diameter,and left ventricular ejection fraction（P<0.05）,and lymphocytes（OR:0.409,95%CI:0.210-0.798,P<0.05）,CHA₂DS₂-VASc score（OR:1.797,95%CI:1.386-2.331,P<0.05）and left atrial diameter（OR:1.120,95%CI:1.039-1.208,P<0.05）were independent risk factors for left atrial appendage thrombosis.According to the Med Calc software,the ROC curve of the prediction of left atrial appendage thrombosis was plotted,and the area under the curve of lymphocytes was 0.591（95%CI:0.522-0.657,P>0.05）,sensitivity 30.95%,specificity 86.29%.The area under the curve for the CHA₂DS₂-VASc score was 0.751（95%CI:0.689-0.807,P<0.05）,sensitivity 60.47%,specificity 83.71%.The area under the curve for the left atrial diameter was 0.757（95%CI:0.695-0.812,P<0.05）,the optimal cut-off was>41mm,the sensitivity was 81.40%,and the specificity was 67.42%.A new thromboembolism prediction scale was constructed by incorporating the left atrial inner diameter of the index with better predictive value into the CHA₂DS₂-VASc score,and comparing the predictive value of the CHA₂DS₂-VASc score and the new score scale for left atrial appendage thrombosis,the area under the CHA₂DS₂-VASc score curve was 0.751（95%CI:0.689-0.807,P<0.05）,sensitivity 60.47%,specificity 83.71%,and the area under the curve of the new score scale was 0.793（95%CI:0.733-0.844,P<0.05）,sensitivity 72.09%,specificity 75.84%.Conclusion:Lymphocytes,CHA₂DS₂-VASc score and left atrial diameter were independent risk factors for left atrial appendage thrombosis in patients with nonvalvular atrial fibrillation,and left atrial diameter and CHA₂DS₂-VASc score had good predictive value for left atrial appendage thrombosis.When the left atrial diameter is>41mm,the left atrial appendage thrombus is greater possibility,and the left atrial idiameter is included in the CHA₂DS₂-VASc score to construct a new thromboembolism prediction scale,which can improve the prediction ability of left atrial appendage thrombus in patients with non-valvular atrial fibrillation.