Preventing in-stent restenosis using lipoprotein (a), lipid and cholesterol adsorbent materials

Atherosclerosis is one of the major cause of mortality in developed countries. The characteristic lesion of atherosclerosis is the atheroma or plaque that forms through thickening of the inner layer of the vessel wall (called the intima). The development of stent in 1980s revolutionised treatment of cardiovascular diseases, including atherosclerosis. However the advent of stenting was hindered by the new problem of in-stent restenosis. It was demonstrated that in-stent restenosis was the result of a new pathology in the form of neointimal hyperplasia, which was a maladaptive healing response to bare-metal stent implantation. Recent evidence suggests that although drug-eluting stent (DES) have reduced restenosis rates, important concerns have been raised regarding increased late stent thrombosis, myocardial infarction and death. With advances in nanotechnology and smart materials, covered stents has been proposed to overcome this problem. This is due to in-stent late restenosis and thromboses are mainly caused by smooth muscle cells (SMC) proliferation. Studies showed that there is a relation between high low-density lipoprotein (LDL) and lipoprotein (a) [Lp(a)] level in blood stream and chance of in-stent restenosis, moreover studies show that Lp(a) could stimulate SMC proliferation. We hypothesis development of covered stent with novel design and use of smart materials which could adsorb cholesterol and prevent contact between Lp(a) and vessel wall to overcome problem indicated in DES. In addition cost of stents will significantly reduce by elimination of drugs as well as complex manufacturing of the drug incorporation.