Vascular stent design

Rogers C, Tseng DY, Squire JC, Edelman ER. Ballon-artery interactions during stent placement a finite element analysis approach to pressure, compliance, and stent design as contributors to vascular injury. Circ Res 1999 84 378-383. 

Clinical studies have conbrmed that coronary stents are only needed during the vascular healing period after the implantation of the stent. Hence, all the long-term problems such as restenosis, thrombosis, and inflammation can be avoided with the development of bio-absorbable vascular stents (BVS) that provide the required support in the early stages after stent implantation and which can then be completely replaced by tissue. In addition to their ability to be fully absorbed within the predetermined time period, BVS is also designed to be able to deliver drugs, as well as other... 

While the design of vascular prostheses and cardiovascular stents has been known and used clinically for many years, it is only within the last 20 years that the idea of combining these two dissimilar technologies together has been proposed with a view to fabricating a single endovascular stent-graft for the repair of aortic aneurysms. 

DESs have been the most recent breakthrough in stent technology. DESs consist of a metal stent covered with a thin polymer coating designed to improve vascular compatibility and elute antiproliferative agents. Drugs such as sirolimus (rapamycin) and paclitaxel serve to reduce restenosis by reducing hyperplasia caused by smooth muscle cell proliferation [37, 38]. 

Finally, some authors caution against placing metalKc stents with hooks and barbs, which are designed to prevent migration, in hypervascularized or vascular tumors since reports of fatal hemorrhage due to stent erosion of vascular structures or hypervascularized tumors have been published (Maynar etal.1993). 

Details are given of the use of the shape memory properties of PU in the design of a fully polymeric vascular endoprosthesis. The possibility of using the stent as a drug delivery system is discussed. 15 refs. 

This study seems to be clinically important since the analysis of vascular mechanics in normal and diseased states is essential for designing stents, surgery planning, treatment and diagnosis of vascular diseases. 

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