Biomechanically Compatible Hydrogel Bioprosthetic Valves

Bioprosthetic cardiac valves are efficient replacements to clinically treat the valvular heart diseases including stenosis and regurgitation, while these often suffer from the issues of mechanical mismatch, biocompatibility, thrombus, degradation, etc. Here, we report a big step toward the biomechanically compatible hydrogel heart valves by the reversible addition-fragmentation chain transfer polymerization compatible threedimensional (RAFT-3D) printing tough hydrogels. The biocompatible hydrogel valves have favorable mechanical properties matching with native valves and long-term stability and durability owing to the wide and robust hydrogen-bonding networks, on which the heparin-like polymer with -SO3- is readily grafted through RAFT polymerization, endowing outstanding hemocompatibility including low hemolysis, anticoagulation, and acceptable inflammatory response. The proof-of-concept hydrogel aortic valve displayed a low transvalvular pressure gradient of 14-24 mmHg, which efficiently regulates the flow direction and regurgitation and, more importantly, endures a cyclic pressure of similar to 80 mmHg for at least 1.8 x 10(5) cycles yet maintaining a stable transvalvular pressure gradient without any damage to the configuration and performance. It is believed that the engineered hydrogel cardiac valves pave a significant way toward addressing the complications of cardiovascular diseases.

Automated summary

This study presents a big step towards biomechanically compatible hydrogel heart valves using RAFT-3D printing technology. These valves have favorable mechanical properties, long-term stability, and durability due to their wide and robust hydrogen-bonding networks. They also exhibit excellent biocompatibility and hemocompatibility. The hydrogel valves efficiently regulate blood flow and can withstand high levels of pressure.