One-third of adults in the U.S. and throughout the world suffer from some form of cardiovascular disease (CVD). The use of bare-metal coronary stents (BMS) for the treatment of CVD increased by 147% from 1996 to 2000, such that 65-80% of treatments now involve stent implantation. Unfortunately restenosis limits the success of BMS in approximately 30-51% of patients. These cases require revascularization of the restenotic lesion and have cost the U.S. healthcare system an estimated 2.5 billion dollars since 1999. Until recently, drug-eluting stents (DES) designed to combat restenosis were being used with such frequency that the global market for stents increased to over 5.4 billion dollars. The efficacy of these devices is now in question since the associated antiproliferative agents used to prevent restenosis also make the vessel prone to late thrombosis that increases the likelihood of myocardial infarction. Collectively, these findings demonstrate that there is an urgent need to reevaluate the current paradigm of treatment and re-examine methods for the engineering of stents. The design of a stent, including its geometry, is an important predictor of restenosis. Stent implantation is known to cause changes in vascular geometry resulting in altered blood flow through the stented region that has been shown to correlate with the development of restenosis. Stent implantation also causes vascular damage, and recent data indicates that adversely altering blood flow can lead to restenosis after this vascular injury. The objective of this project is to develop a novel stent geometry that diminishes restenosis and the potential for thrombus formation by intrinsically minimizing blood flow disturbances after implantation. Optimizing local flow patterns created by the stent may inherently reduce blood flow alterations associated with restenosis and thrombus formation while avoiding the use of deleterious agents that are required for current drug-eluting designs.
Restenosis after traditional bare-metal stent implantation limits the success of stents and has cost the U.S. healthcare system an estimated 2.5 billion dollars since 1999. Drug-eluting stents designed to combat restenosis are prone to late thrombosis that increases the likelihood of myocardial infarction. These problems with traditional bare-metal and drug-eluting stents can be explained on the basis of altered blood flow within the stented region, and this project will create a stent that minimizes flow disturbances to intrinsically reduce restenosis and the potential for thrombus formation and dislodgement. ? ? ?
