Addressing the performance challenges of fully biodegradable cardiac occluders: a review on material advances and 4D-printing fabrication strategies

The development of fully biodegradable cardiac occluders presents unique performance challenges, particularly requiring a balance between initial mechanical strength, appropriate degradation kinetics, and enhanced biocompatibility. Although 4D printing offers promising prospects for manufacturing personalized cardiac occluders, there remains a lack of systematic reviews elucidating how material properties and printing strategies can overcome these performance bottlenecks. This review systematically analyzes research findings on the material-property-processing relationships of materials such as aliphatic polyesters and their application in occluder development. Findings indicate that material modification combined with 4D printing parameter control can achieve nonlinear stress-strain behavior and customized degradation profiles-properties critical for cardiac tissue repair. We contend that integrating material design with 4D printing processes represents a key direction for achieving high-performance, personalized cardiac occluder design and manufacturing.