Wang Weiwei Team at Institute of Biomedical Engineering Unveils Modified Biodegradable Cardiac Occluder

In June 2022, the team led by Wang Weiwei at the Institute of Biomedical Engineering, Chinese Academy of Medical Sciences, filed a patent for a modified biodegradable occluder.This patent addresses the issue of prolonged inflammatory responses caused by the poor biocompatibility of materials in existing clinically used degradable cardiac occluders., and entered the patent publication stage in September of the same year.

Despite significant progress in the design and manufacturing of current bioresorbable occluders, the inherent disadvantages of biodegradable polymer materials themselves limit further enhancement of the advantages of bioresorbable occluders.

Ideally, materials for degradable occluders must not only undergo autonomous biodegradation in vivo over a defined period but also exhibit excellent biocompatibility and sufficient mechanical properties. To this end,Wang Weiwei’s team developed a cost-effective and technically mature surface modification method for occluder materials, enabling the fabrication of biodegradable cardiac occluders with reliable performance and rapid endothelialization.。

Therefore, bio-based biodegradable polymer materials, as alternatives to traditional petroleum-based plastics, have developed rapidly in recent years. Taking biodegradable plastics as an example, the total market volume is expected to exceed 3 million tons by 2025, with a compound annual growth rate of 20%.

In specific medical applications, polylactic acid, polydioxanone (PDO), and polyglycolic acid have begun to be widely used in the field of cardiovascular diseases.. In the field of vascular stents, Abbott developed the first everolimus-eluting polylactic acid stent for human use in 2006, with the scaffold material primarily consisting of poly-L-lactic acid. In March 2009, research findings by Patrick et al. demonstrated favorable absorption of the BVS stent two years after implantation, with no evidence of lumen restenosis or in-stent thrombosis.

In the field of cardiac occluders, Christian Jux and NMT Medical, Inc. of Boston, USA, designed the first-generation bioabsorbable BioSTAR occluder in 2003. This device utilizes a submucosal collagen layer from the small intestine for its bioabsorbable membrane, demonstrating a certain level of safety in clinical applications. Subsequently, the Singapore University of Technology and Design developed a fully biodegradable occluder for atrial septal defect (ASD) and patent foramen ovale (PFO). The left and right atrial discs of this occluder are fabricated from polycaprolactone (PCL), providing superior anchoring stability, while the membranes on both discs are made from a polycaprolactone-lactide copolymer.

As clinical research continues to deepen,The future development trend of biodegradable materials is to further integrate functionality and technology into polymers, and to develop next-generation products such as stents, occluders, catheters, and tissue repair materials.。

For example, the integration of biodegradable materials with 3D printing technology. In 2016, the Surgical Dream Factory team at the First Affiliated Hospital of Xi’an Jiaotong University developed a 3D-printed biodegradable magnetic anastomosis ring, which can be widely applied in medical fields such as gastrointestinal tract reconstruction, magnetic anastomosis and reconstruction of small and medium-sized blood vessels, and personalized treatment for special clinical cases. In 2024, Professor Danyang Zhao’s research group at Dalian University of Technology, in collaboration with Professor Yifei Jin’s team at the University of Nevada, Reno, and other partners, proposed a novel multi-scale immersion printing strategy capable of 3D printing hearts.

In the market, the AMsorb 3D-printed biodegradable coronary stent, independently developed by Beijing Amate Medical, features a pioneering spiral-arranged closed-cell structure. The cross-sectional area of its struts is reduced by 41% compared to laser-cut counterparts, while the stent also demonstrates excellent flexibility and radial support strength.