Midterm follow-up results of implantation of a fully biodegradable ventricular septal defect occluder.

Objectives: Ventricular septal defect (VSD) is a prevalent congenital cardiac anomaly. By enhancing the occluder design and optimizing procedural approaches, the indications for VSD closure can be broadened while minimizing associated complications. The utilization of fully biodegradable occluder holds promising potential in resolving conduction block issues encountered during VSD closure. This study aims to compare the results of the fully biodegradable occluder with the metal occluder in transoesophageal echocardiography-guided VSD closure via lower sternal level minor incision at the interim follow-up, and to find risk factors for the occurrence of electrocardiographic and valvular abnormalities postoperatively.

Methods: We reviewed the postoperative and 3-year follow-up data of all patients who underwent the randomized controlled study of VSD closure from January 1 to November 7, 2019 in the Second Xiangya Hospital of Central South University. The safety and efficacy of the procedure were assessed and compared between the 2 groups by electrocardiogram and echocardiography results, and the risk factors for the occurrence of postoperative electrocardiogram and valve abnormalities were studied with Logistic regression analysis.

Results: Twelve and fifteen patients underwent VSD closure with the metallic occluder and the fully biodegradable occluder, respectively. All patients survived during the follow-up period without major complications such as atrioventricular block, significant residual shunt, too rapid absorption of the occluder, and significant valvular regurgitation. There were no significant differences in the results of electrocardiograph and color Doppler ultrasonography the metal occluder group and the fully biodegradable occluder group 1, 2, and 3 years after operation (all >0.05). The size of the occluder were risk factors for tricuspid regurgitation at 2 and 3 years postoperatively, and the difference between the occluder size and the VSD defect size were risk factors for tricuspid regurgitation at 2 years postoperatively (<0.05).

Conclusions: This study adequately demonstrates the safety and efficacy of fully biodegradable occluders in small VSD closure and shows the same postoperative effects as conventional nitinol occluders.