Objective To evaluate the complications and the changes of cardiac chamber size and cardiac function caused by percutaneous left atrial appendage occlusion（LAAC） in patients with non-valvular atrial fibrillation by echocardiography

and to explore the application value of echocardiography in LAAC.Methods A total of 205 patients with non-valvular atrial fibrillation who underwent LA AC in our hospital were selected.The parameters of anteroposterior diameter of left atrium at the end of systole（LAD）

end-diastolic left ventricular anteroposterior diameter（LVDd）

transverse diameter of right atrium at the end of systole（RAT）

end-diastolic anteroposterior diameter of right ventricle（RVD）

ejection fraction of left ventricle（LVEF）

left ventricular shortening fraction（LVFS）

end diastolic volume（EDV） and stroke volume（SV） at different time points were measured before LAAC and 48 h

3～6 months and 1 year after LAAC.The complications of the patients were summarized.Results Among the 205 patients with atrial fibrillation

LAAC was successfully completed in 202 cases（98.5%）.Compared with those before operation

LVEF

LVFS and SV were increased 48 h after LAAC

and the differences were statistically significant（all P<0.05）.Compared with those before operation

there were no significant differences in the parameters between 3～6 months and 1 year after LAAC.Among the 205 patients with atrial fibrillation

there were occluder-related thrombosis in 17 cases（8.4%）

pericardial effusion in 4 cases（2.0%）

residual shunt around the occluder in 29 cases（14.4%

shunt beam spacing<5 mm）.No occluder exfoliation and displacement occurred in all patients.Conclusion Echocardiography has important value in the preoperative detection

intraoperative guidance and postoperative follow-up of LAAC

which is the key to ensure the success of LAAC.