Relationship between left atrial appendage function and embolic risk in nonrheumatic atrial fibrillation assessed by transesophageal echocardiography

AIM:To explore the value of transesophageal echocardiographic assessment of left atrial appendage(LAA) function for identifying thromboembolic risk in patients with nonrheumatic atrial fibrillation. METHODS:Transthoracic and trnsesophageal echocardiographic examinations were performed in 66 patients with nonrheumatic atrial fibrillation. The patients were divided into two groups according to the LAA blood emptying velocity assessed by transesophageal echocardiography:group I(25 cm/s, n =18) and group Ⅱ(≥25 cm/s, n =28). The incidences of left atrial thrombus and spontaneous echo contrast as well as other clinical and echocardiographic factors associated with throboembolism were compared between the two groups. RESULTS:In group Ⅰ,the incidences of atrial thrombus and spontaneous echo contrast were significantly higher than those in groupⅡ ( P 0.01), and LAA enlargement was closely correlated with reduced LAA blood velocity ( r =-0.544, P 0.01). Previous embolic events,left atrial diameter dilatation and left ventricular dysfunction were common in group Ⅰ than in group Ⅱ ( P 0.05), but no significant differences were observed in age,history of hypertension and diabetes( P 0.05). CONCLUSION:Left atrial appendage function assessed by transesophageal echocardiography may be helpful for identifying subgroup of patients with nonrheumatic atrial fibrillation at higher thromboembolic risks.