Self-Cleansing Flexible Stent for Prevention of Clogging of Blood Vessels

Different types of stents are available to be implanted into blood-vessels (e.g., cardiovascular stent) or organs to maintain unobstructed blood flow or flow of tissue fluid through ducts (e.g., biliary and uretic stents and others). On the one hand, it is imperative to use smart material such that its mechanical and elastic properties meet those of the ideal stent. A smart stent can change the orientation of the material(s) either by sensing control, temperature, or blood pressure, thus alter the overall shape of the stent (wiggling). These wiggling motions can prevent or reduce the deposit of cholesterol inside the stent’s lumen. On the other hand, there is a need for a better physiological model of how the tensile and shear stresses of a blood vessel are altered as the blood pressure changes along a defined length of that vessel and how the shape changes of the blood vessel could prevent the deposits of lipid material on the vessel wall thereby possibly decrease the likelihood of stenosis. However, the design of an ideal stent is complicated by the lack of proper materials and modeling studies, and difficulties to have an optimized design because of complexities of environmental factors. In this literature review, we therefore propose that an optimal stents design should incorporate the use of highly biocompatible material(s) of well characterized properties and with an adequately modeled mechanical design. We have discussed the importance and relevance of these issues for future stent design and fabrication.