Left atrial enlargement and non-paroxysmal atrial fibrillation as risk factors for left atrial thrombus/spontaneous Echo contrast in patients with atrial fibrillation and low CHA2DS2-VASc score

摘要

Objective To determine the risk factors for thromboembolism in lower risk patients with non-valvular atrial fibrillation(AF)and low CHA2DS2-VASc scores,which remain undefined.Methods We retrospectively analyzed the baseline clinical characteristics,routine laboratory parameters,and echocardiographic measurements of 705 patients(71.1%male;mean age:52.10±9.64 years)with low CHA2DS2-VASc score(0 or 1;1 point for female sex)out of 1346 consecutive patients with non-valvular AF who underwent transesophageal echocardiography(TEE)at Guangdong Cardiovascular Institute between January 2013 and December 2015.Results Patients with left atrial thrombus(LAT)or spontaneous echo contrast(SEC)on TEE(24/705,4%)showed a higher incidence rate of vascular disease(54.2%vs.32.9%,P=0.045)and non-paroxysmal AF(79.2%vs.29.4%,P<0.001),larger left atrial diameter(43.08±4.59 vs.36.02±5.53 mm,P<0.001),and lower left ventricular ejection fraction(58.23±8.82%vs.64.15±7.14%,P<0.001)than those without.Multivariate logistic regression analysis identified left atrial diameter[odds ratio(OR)=1.171,95%confidence interval(CI):1.084–1.265,P<0.001]and non-paroxysmal AF(OR=3.766,95%CI:1.282–11.061,P=0.016)as independent risk factors for LAT/SEC.In ROC curve analysis,a left atrial dimeter cutoff of 37.5 mm yielded 95.0%sensitivity and 62.7%specificity(AUC:0.847,P<0.0001,95%CI:0.793–0.914).Conclusion In patients with non-valvular AF with low CHA2DS2-VASc score,the presence of LAT or SEC was associated with left atrial enlargement,which had moderate predictive value,and non-paroxysmal AF.