Influce Of Ischemic Preconditioning On Neointimal Coverage After Drug-eluting Stents Implantation

Objective The application of drug-eluting stents (DES) significantly reduced the incidence of stent restenosis, but increased the risk of stent thrombosis. Early related autopsy studies suggested the continued bare stents struts which may caused by delayed repair and healing of vascular intima and stent malapposition after drug-eluting stent implatation was closely related to the occurrence of stent thrombosis. The rate of neointimal coverage is proportional to the degree of reendothelialization, the level of neointimal coverage also reflects the level of reendothelialization. So reendothelialization is very important to prevent the occurrence of stent thrombosis. At present, the measures of prenernting stent thrombosis mainly contain sustained and effective dual antiplatelet therapy, improvement of DES, the secondary prevention of coronary heart disease and reasonable clinical decision, etc. lschemic preconditioning (IPC) is a method which can induce the body to play a role of endogenous protection, and make it resistant to ischemia for a longer time.Its mechanisms are as follows:theory of adenosine, theory of mitochondrial ATP enzyme inhibition, theory of protein kinase C, theory of prostacyclin and nitric oxide and stem cells theory, etc, but there is still much controversy. The role of stem cells in ischemic preconditioning has become a research hotspot among them. The experiment proved that many remote organs’ ischemia,such as kidney, mesentery and limb etc, can play the same protective effect as IPC. The mechanism of remote ischemic preconditioning (RIPC) is unknown so far. We infer that RIPC can induce the body’s powerful endogenous protective mechanism and to repair damaged vascular endothelium and promote neointimal coverage,so the risk of stent thrombosis can reduce. Optical coherence tomography (optical coherence tomography,OCT) can clearly display the neointimal coverage and accurately measure neointimal indicators, it is sigificant to evaluate the efficacy of the interventional treatment and study of stent thrombosis.Based on the above, the subject is to explore the influce of ischemic preconditioning on neointimal coverage after DES implantation. Methods We chosed patients with multivessel coronary artery disease who had received staged percutaneous coronary intervention,which means culprit vessel was diposed firstly and other lesion vessels would be disposed after about 1 monnth.Thses patients were randomly divided into group A (n=19,received ischemic preconditioning) and group B (n=20,not received ischemic preconditioning), and 1 month was regard as one course of treatment, the rate of strut coverage,stent malapposition,neointimal hyperplasia (NIH) thickness, lumen area, stent area of the part in which the first stent was invented were evaluated by OCT (optical coherence tomography) when other lesion vessels were disposed.Results OCT showed that there was significant difference between group A and group B in the rate of neointimal coverage(73.6%±12.6% vs 69.4%±10.2%,P< 0.05),while there was no significant difference in the rate of stent malapposition,NIH thickness,luman area,stent area (0.8%±1.5% vs 1.8%±2.1%;49.7±15.0um vs 53.1 ±16.2um;8.6±2.6mm2 vs 7.4±3.2mm2;9.4±3.0 vs 8.3±3.5mm2;P>0.05).Conclusion Noninvasive limb ischemic precondition (NILIPC) can improve the rate of strut coverage in order to decrease the occurrence rate of thrombosis in stent,while the rate of stent malapposition, NIH thickness,luman area and stent area were not significantly affected.