Construction of left atrial appendage three-dimensional model based on transesophageal echocardiography and its value in preoperative simulated left atrial appendage closure

Abstract

Objective To evaluate the accuracy of simulated operation before the left atrial appendage (LAA) occlusion by filed LAA model with soft materials, which is based on transesophageal three-dimensional echocardiography (3D-TEE). Methods Silica and hydrogel were mixed to imitate cardiac tissue. Silica and hydrogel mixed materials, silica and Tangoplus were subjected to mechanical detection and ultrasonic shear wave elastography (SWE). The preoperative and postoperative 3D-TEE image processing was performed on 21 patients undergoing LAA occlusion. The silica and hydrogel LAA 3D model, silicone model and Tangoplus model were acquired to evaluate the accuracy of 3D model. LAA closure was simulated using the 3D models and the compression ratio of the device in models was compared with the value measured in operation. Results The silica and hydrogel mixed materials were successfully prepared. The elastic modulus and stress-strain curve were closer to the myocardial tissue. Twenty-one 3D printing models of three materials were obtained in 21 patients based on 3D-TEE images.There was no significant difference in the anchor zone between the 3D model and 3D-TEE (P>0.05). The 3D model measurements were consistent with the 3D-TEE measurements. The compression ratios of the decive in the 3D models of all three materials were greater than those measured in operation, and the compression ratio of the device in the 3D model of silica and hydrogel materials had a better correlation with that measured in operation (r=0.900, P<0.01). Conclusions The 3D model of LAA made of silica and hydrogel material based on 3D-TEE can improve the accuracy of the LAA occlusion simulation, also can optimize the preparation of LAA occlusion. Key words: Echocardiography, transesophageal, three-dimensional; Three-dimensional printing; Left atrial appendage; Soft printing material