Simplified left atrial appendage occlusion (LAAO) is one of the important treatment methods for preventing thromboembolism in patients with nonvalvular atrial fibrillation. Currently, there are few studies on the value of cardiac 3-dimensional computed tomography (3D-CT) in the simplified LAAO.

To investigate the feasibility, safety, surgical efficacy and postoperative follow-up value of 3D-CT in simplified LAAO.

We prospectively recruited 52 patients who underwent simplified LAAO in the Second Affiliated Hospital of Anhui Medical University from May 2021 to January 2024. They were randomly assigned into the control group and study group by lottery. Preoperative transesophageal echocardiography (TEE) and preoperative cardiac 3D-CT were performed in the control group and study group, respectively. The baseline data, maximum ostium diameter and maximum depth of the left atrial appendage (LAA), match rate between the delivered sheath and the axis of LAA, operation time, time for x-ray exposure and dose, consumption of contrast agent, the rate of non-recapture and non-change of occlusion device, peri-device leakage (PDL), and perioperative complications were collected. A 3D-CT follow-up was performed for 90 days after LAAO.

Both the control group and the study group comprised 26 cases each, using the WATCHMAN device for LAAO, with no serious perioperative complications. Preoperative examinations showed no intracardiac thrombus in all patients. In the control group, the maximum ostium diameter of the LAA measured by preoperative TEE and intraoperative DSA was (22.9±4.1) mm and (25.4±2.9) mm, respectively, not showing a positive correlation (r=0.374, P=0.060). The usable depth of the LAA in the control group measured by preoperative TEE and intraoperative DSA was (25.7±8.1) mm and (23.7±3.4) mm, respectively, showing a positive correlation (r=0.392, P=0.048). In the study group, the maximum ostium diameter of the LAA measured by preoperative 3D-CT and intraoperative DSA was (25.0±3.3) mm and (24.9±5.8) mm, respectively, showing a positive correlation (r=0.566, P=0.003). The usable depth of the LAA in the study group measured by preoperative 3D-CT and intraoperative DSA was (23.5±4.2) mm and (23.1±4.0) mm, respectively, showing a positive correlation (r=0.774, P<0.001). The match rate between the delivered sheath and the axis of LAA was significantly higher in the study group than that of control group (96.2%, n=25; 76.9%, n=20; χ²=4.172, P=0.042). Patients in the study group had significantly shorter atrial septal puncture time, occlusion time, and exposure time to X-ray, and lower X-ray dose and consumption of contrast agent compared to those of the control group (P<0.05). The incidence of intraoperative minor PDL in the study group was significantly lower than that in the control group (P<0.05). A total of 37 patients, with 16 cases in the control group and 21 in the study group, completed the 90-day follow-up after LAAO. No device-related thrombus (DRT) or PDL larger than 5 mm was found, and incomplete device endothelialization was observed in some patients.

Reoperative cardiac 3D-CT in simplified LAAO benefits a shorter operation time, shorter fluoroscopy time, less dosage to X-ray exposure, and lower rate of minor PDL. It also demonstrates certain advantages of detecting incomplete endothelialization in postoperative follow-up. With the advancement of 3D-CT in the application of LAAO, it can be combined with 3D printing technology in the future to simulate the procedural process accurately, making LAAO safer and more efficient.