Polymeric Antithrombotic Coatings for Blood-Contacting Medical Devices: Evolution from Passive Protection to Adaptive Regulation

Blood-contacting medical devices are indispensable for the treatment of cardiovascular diseases, yet they are prone to inducing thrombosis after implantation, leading not only to device failure but also to life-threatening complications. To address this issue, various polymeric antithrombotic coating design strategies have been proposed, ranging from passive inhibition of protein adsorption to direct coagulation cascade intervention, active inflammatory microenvironment regulation and re-endothelialization promotion. Moreover, to satisfy the sequential antithrombotic requirements during long-term implantation, self-adaptive antithrombotic coatings have emerged, which can regulate the pathological microenvironment on device surfaces and enable the on-demand switching of surface functions. Specifically, such coatings are expected to initially inhibit protein adsorption, prevent platelet activation, and block coagulation cascade initiation; subsequently modulate the inflammatory microenvironment; and eventually promote surface re-endothelialization to achieve durable antithrombotic performance. This review systematically summarizes the pathological processes of device-associated thrombosis, the main antithrombotic coating design strategies, and the commonly used coating fabrication techniques. Finally, the prospects of next-generation antithrombotic coatings are presented in terms of computation-driven rational design, endothelium-mimetic adaptive coatings, and spatially programmed personalized fabrication.