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The implanted materials and devices can be recognized by the immune system, which in turn mediate the immune microenvironment of tissues. The immune system in mammals is composed of diverse components such as immune cells, cytokines, radicals and antibodies etc. Chiral polymers with good biocompatibility, tailorable ability and ease of fabrication are excellent candidates for diverse biomedical applications. Different chiral biomaterials have been investigated to study the interactions of immune cells and the resulted immune responses, but the effects of chiral polymers on immune regulation are less tackled. Tailoring the chemical and physical properties of chiral polymers can lead to beneficial immune responses. This review focuses on the different fabrication strategies of chiral polymers and interactions of chiral polymers with immune cells and other biological components. The adhesion and interaction patterns of chiral polymers with immune cells, changes in shapes and characteristics of cells, release or inhibition of cytokines, and resulting response are discussed in the review.

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. Transcatheter aortic valve replacement has become a dominant technique in the treatment of valvular heart disease, among which biological valves and polymeric valves are the mainstream choice and potential substitutes in the future, respectively. In this review, the anti‐calcification modification of biological valves and the development of new polymeric valves in recent years are summarized, and future perspectives are discussed.