Abstract:

Objective To investigate influencing factors of left atrial thrombus(LATH) or spontaneous echo contrast (SEC) in patients with nonvalvular atrial fibrillation (NVAF). Methods One hundred and thirty patients with NVAF were collected in this study.CHA2DS2VASc risk scores for each patient were calculated.The baseline clinical data were detected，  including gender， age，concomitant diseases， laboratory parameters and ecocardiography.The patients were divided into left atrial thrombus or spontaneous echo contrast positive group and negative group according to the result of transeophageal ecocardiography（TEE）.The parameters between the two groups were compared，receptoroperating curves（AUC） were used to test the value of CHA2DS2VASc score，left atrial diameter(LAD)，left atrial appendage filling velocity and left atrial appendage emptying velocity predicting left atrial thrombus or spontaneous echo contrast．Logistic analysis was used to find the independent predictor of left atrial thrombus or spontaneous echo contrast. Results There were significant differences in left atrial diameter(LAD)， left ventricular enddiastolic diameter (LVEDD)，left ventricular ejection fraction(LVEF)，the proportion of persistent atrial fibrillation，previous history of stroke or transient ischemic attack (TIA)， body mass index（BMI），CHA2DS2VASc score，left atrial appendage emptying velocity，left atrial appendage filling velocity between the two groups.In multivariate analysis，LAD>40.0 mm(P=0.01)， left atrial appendage emptying velocity＜54.15  cm/s(P<0.01)， BMI≥25(P<0.01) were independently associated with left atrial thrombus or SEC in patients with NVAF.The AUC of LAD to predict left atrial thrombus or SEC was 0.845(95%CI=0.7760.913，P<0.01)，the sensitivity and specificity were 67.6％  and  88.7％.The AUC of left atrial appendage emptying velocity to predict left atrial thrombus or SEC was 0.851(95%CI=0.7810.921，P<0.01)，the sensitivity and specificity were 83.9％  and   74.9％. Conclusion  LAD>40.0 mm，left atrial appendage emptying velocity＜54.15  cm/s are independent risk factors of left atrial thrombus or spontaneous echo contrast in patients with NVAF.

Key words: atrial fibrillation, thrombosis, autoradiography