Prosthetic heart valves for transcatheter aortic valve replacement

Abstract

Transcatheter aortic valve replacement (TAVR) has the advantages of less trauma and faster postoperative recovery, which has brought the possibility to the elderly patient with valvular heart disease and is gradually replacing surgical aortic valve replacement (SAVR). The interventional valve used in TAVR needs to be compressed and transported through the catheter to the lesion site, and can still recover its original shape, structure and performance. This process requires that the material should be flexible, and the rigid mechanical valves in SAVR are not suitable. Recently, decellularized biological valves have been widely used in clinical practice, but their poor durability causes a limitation for long-term implantation. Therefore, the anti-calcification modification of biological valves and the design of new polymeric valves with good biostability have gained considerable attention. This review summarizes the calcification mechanism of biological valves and the research progress in anti-calcification modification strategies. Besides, the development of new polymeric valves is included, with special attention to representative cases, such as polysiloxane, polytetrafluorethylene, poly(styrene-block-isobutylene-block-styrene), and polyurethane-based materials. Finally, the challenges and future perspectives of artificial heart valve materials are discussed.