To evaluate the value of transesophageal echocardiography in the preoperative screening, intraoperative monitoring, and postoperative follow-up in patients undergoing percutaneous left atrial appendage (LAA) occlusion.

Fifty-four patients with atrial fibrillation were treated by percutaneous closure of the LAA with the Watchman occluder in Wuhan Asia Heart Hospital from January 2016 to December 2016. According to whether there was residual shunt after closure, the patients were divided into a residual shunt group and a non-residual shunt group. Before the operation, all patients were examined by transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE), and patients with valvular pathological changes or left atrial appendage thrombus were excluded. The maximum opening and depth of the LAA were measured by TEE before operation. During the operation, TEE guided atrial septum puncture combined with X-ray angiography were used to select the occluder model, guide the location of the blocking transmission system and the release of the occluder, and evaluate the safety of the operation. The follow-up ultrasound examination was performed immediately and 45 days after the operation. The t-test was used to compare the maximum and minimum compression ratios between the two groups. The correlation between the maximum opening diameter of the LAA measured by TEE and the size of the selected occluder was analyzed by the Pearson method.

Fifty-four patients who underwent left atrial appendage occlusion were successfully occluded, and the compression ratio was between 8% and 20%. The comparison of the maximum and minimum compression ratios differed significantly between the residual shunt group and the non-residual shunt group [(17.70±2.28)% vs (17.10±2.42)%, (12.40±2.82)% vs (12.60±2.68)%, all P>0.05]. In 87% (47/54) of the patients, the maximum opening and depth of left atrial appendage were obtained by TEE at 135°. There was a significant positive correlation between the maximum LAA opening diameter measured by TEE at four angles and the LAA opening diameter measured by TEE at 135°, between the maximum LAA opening diameter measured by TEE and the LAA opening diameter measured by X-ray angiography, as well as between the LAA opening diameter measured by TEE at 135° and the selected occluder model (r=0.919, 0.622, 0.602, all P<0.001), and the correlation equations were: Y=1.01X+ 1.11, Y=0.68X+ 6.56, and Y=0.80X+ 1.24, respectively. There were no cerebrovascular or other vascular embolization events in all patients undergoing follow-up. A small amount of pericardial effusion was found in three cases with cerebrovascular or other vascular embolism. No pericardial effusion was found at 7 d after operation, and thrombus appeared on the surface of the occluder in two cases at 45 d after the operation.

TEE is of great value for the screening of patients before LAA closure, the selection of percutaneous puncture and occluder model, the guidance of the release process, the immediate assessment of the blocking effect, and the postoperative follow-up. TEE performed at 135° is more sensitive for residual shunt detection than that performed at other angles.