Correlation between left atrial appendage density ratio and flow velocity in patients with different types of atrial fibril-lation by MSCT and TEE

FU Rong; LI Caiying; JIAO Yang; MENG Yuanyuan; CHEN Yicheng; NI Jiqiong; ZHENG Tongtong

Abstract：Objective To measure CT ratio of distal sites of the left atrial appendage to ascending aortic artery(LAAD-AA)in patients with different types of atrial fibrillation by 256-slice spiral CT,to observe the correlation between density ratio and left atrial appendage emptying velocity(LAAEV)measured by transesophageal ultrasound(TEE),and to explore its clinical signifi-cance.Methods 152 patients with atrial fibrillation who had been completed cardiac CT angiography and TEE within 14 days were collected,including 46 patients with persistent atrial fibrillation(PeAF)and 106 patients with paroxysmal atrial fibrillation(PAF).The maximum volume of left atrium(LAVmax),the opening area of left atrial appendage,the depth and density ratio of left atrial appendage were measured quantitatively by cardiac function post-processing software.The presence of left atrial ap-pendage thrombus and spontaneous echo contrast(SEC),as well as LAAEV were measured by TEE.Results The proportion of patients with heart failure,the number of SEC,heart rate,LAVmax and the area of left atrial appendage orifice in PeAF group were higher than those in PAF group(P<0.05).LAAEV and LAAD-AA in PeAF group were lower than those in PAF group(P<0.05).LAAD-AA was smaller in the PeAF than that in the PAF group(P<0.05).The depth of left atrial appendage was not seen the difference in the two groups(P>0.05).Atrial fibrillation(P=0.011),the area of left atrial appendage orifice(P=0.005)and LAAD-AA(P<0.001)were the main factors affecting LAAEV.LAAEV and LAAD-AA were significantly correlated both in PeAF group and PAF group(r=0.704 and 0.585,P<0.001).The critical value of LAAD-AA was 0.410.When LAAEV≤25cm/s in PeAF group,the sensitivity was 100%and specificity was 74.1%.When LAAEV≤25cm/s in PAF group,the sensitivity was 100%and specificity was 92.6%.Conclusion The correlation between left atrial appendage density ratio and flow velocity is different in different types of atrial fibrillation,which is of great clinical value in predicting stroke risk in pa-tients with atrial fibrillation.