3D printing and biocompatibility study of a new biodegradable occluder for cardiac defect.

OBJECTIVE: To fabricate a biodegradable occluder for heart defect using the three-dimensional (3D) printing technique and evaluate its biosafety in an animal model. METHODS: Occluder samples were made by 3D printing technique using the self-developed lactide-sanya methyl carbonate-glycolide (PLLA-TMC-GA) co-polymer or PLTG as the bio-material. The biocompatibility (cytological and hematological) of the materials was evaluated by cytotoxicity experiments, hemolysis test, dynamic blood clotting test, and platelet adhesion test. Finally, the histocompatibility of the occluder was evaluated by implantation in a rabbit model. RESULTS: Occluder samples were printed satisfactorily. Cytotoxicity assay showed no significant toxicity of PLTG in the cells. Hemolysis test showed less than 5% hemolysis rate of PLTG indicating only a mild effect on the red blood cells. The dynamic coagulation test showed poor activation of endogenous clotting factors. PLTG resulted in lower platelet activation compared to PLLA, as indicated by the platelet adhesion test. Finally, no obvious tissue damage or necrosis was seen in the in vivo implantation experiment. CONCLUSION: A new PLTG-based biodegradable occluder for heart defects with good biocompatibility can be manufactured by the 3D printing technique.