The Technological Advancement to Engineer Next‐Generation Stent‐Grafts: Design, Material, and Fabrication Techniques

Abstract

Endovascular treatment of aortic disorders has gained wide acceptance due to reduced physiological burden to the patient compared to open surgery, and ongoing stent-graft evolution has made aortic repair an option for patients with more complex anatomies. To date, commercial stent-grafts are typically developed from established production techniques with simple design structures and limited material ranges. Despite the numerous updated versions of stent-grafts by manufacturers, the reoccurrence of device-related complications raises questions about whether the current manfacturing methods are technically able to eliminate these problems. The technology trend to produce efficient medical devices, including stent-grafts and all similar implants, should eventually change direction to advanced manufacturing techniques. It is expected that through recent advancements, especially the emergence of 4D-printing and smart materials, unprecedented features can be defined for cardiovascular medical implants, like shape change and remote battery-free self-monitoring. 4D-printing technology promises adaptive functionality, a highly desirable feature enabling printed cardiovascular implants to physically transform with time to perform a programmed task. This review provides a thorough assessment of the established technologies for existing stent-grafts and provides technical commentaries on known failure modes. They then discuss the future of advanced technologies and the efforts needed to produce next-generation endovascular implants.

Expanded Polytetrafluoroethylene Membranes for Vascular Stent Coating: Manufacturing, Biomedical and Surgical Applications, Innovations and Case Reports

“…In recent years, efforts have been made to develop new stent graft devices by focusing on smart or reactive materials designed to have one or more properties that can be transformed in a controlled manner by external stimuli such as stress, humidity, electric or magnetic fields, light, temperature, pH or chemical compounds [ 97 ]. In this regard, shape memory materials (SMM) have been identified that can be transformed and fixed in a temporary form, recovering their original shape when subjected to an appropriate stimulus [ 98 ].…”

Design strategy of poly (L‐lactic acid) mixed braided stent: The influence of braiding ratio of thick and thin monofilaments

“…15,16 The most common method to regulate the radial force is to adjust the braiding parameters and/or structure of the stent, in which the braiding parameters mainly include the diameter of the stent, the diameter of the monofilament, and the braiding angle. [17][18][19][20][21] In addition, structural design can also be optimized to improve supportability. Innovative methods about flow channels, such as adding new flow channels in axial, circumferential, and helical directions, have always been considered to obtain better structural stability.…”

“…To date, researchers have conducted a lot of research on supportability, especially for polymer stents with weak mechanical properties 15,16 . The most common method to regulate the radial force is to adjust the braiding parameters and/or structure of the stent, in which the braiding parameters mainly include the diameter of the stent, the diameter of the monofilament, and the braiding angle 17–21 . In addition, structural design can also be optimized to improve supportability.…”

Recent Progress on Optical Tomographic Technology for Measurements and Inspections of Film Structures

“…By adopting interferometric principles, optical coherence tomography (OCT) has been increasingly developed and commercialized in the biomedical area. Furthermore, the biomedical devices such as stents, implants, wires and catheters need the surface coating to protect the devices from corrosion as well as infection from disease, and the coated film should be carefully inspected to avoid unexpected hazards [ 17 , 18 ].…”

“…By adopting interferometric principles, optical coherence tomography (OCT) has been increasingly developed and commercialized in the biomedical area. Furthermore, the biomedical devices such as stents, implants, wires and catheters need the surface coating to protect the devices from corrosion as well as infection from disease, and the coated film should be carefully inspected to avoid unexpected hazards [17,18]. Typically, a scanning electron microscopy (SEM) and a transmission electron microscopy (TEM) have been widely used to inspect the metallic, organic and inorganic film structures with high precision [19,20].…”