The Evaluation Of Endothelialisation Of BuMA Supreme Biodegradable Polymer Durg-Eluting Stents

Background:The first generation of DES was born by spraying a non-degradable polymer on the surface of a metal stent and using paclitaxel and sirolimus as carrier drugs.However,the first-generation DES stent thrombosis is more prominent.After a series of improvements in stent materials,anti-proliferative drugs,and drug coating technologies,second-generation DES were formed.In particular,the application of biodegradable polymer coating technology provides the possibility to further reduce the incidence of stent thrombosis and shorten the dual antiplatelet therapy(DAPT)course.Optical coherence tomography(OCT)is an intracavitary imaging technique that uses tissue imaging analysis of near-infrared light reflected from tissue to provide near-histological resolution(10-20um)for stent grafts.After entering the intimal hyperplasia of the inner vessel,it can provide a more accurate assessment.Objective:In order to provide proof for less time of dual antiplatelet therapy(DAPT),We decided to evaluate the tissue coverage of the patients with high risk of bleeding between BuMA Supreme stent and Xience Prime stent by Optical Coherence Tomography(OCT)at 1 mounth after PCI.Method:Enroll the patient according to the PIONEER-? OCT study,who suffered coronary atherosclerotic heart disease(CHD)with high risk bleeding,and receive coronary angiography in hospitals(The second Affiliated Hospital Of Nanchang University,Chinese PLA General Hospital,Shanghai Ninth People's Hospital,Wuhan ASIA Heart Hospital,Affiliated Hospital Of Zunyi Medical College,The affiliated Hospital Of Dalian Medical University,Sir Run Run Shaw Hospital)from June 2016 to August 2016,and assign them to BuMA Supreme group and Xience Prime group.At 1 month after PCI,we perform another CAG and OCT to get the OCT image.We catch a cross-section every 1mm(5 frames)within the stent segment.In each cross-section,we count the number of struts,observe the malapostion and coverage of each strut,measure the thickness of neointimal.And statistical analysis was done for the stent endothelialization between two groups.The primary endpoint is the coverage of stent struts.The second endpoint is the average thickness of neointimal.Result:The PIONEER-? OCT study included 40 patients who had been followed up for one month after stent implantation,and excluded 17 patients with poor image quality and unable to obtain valid data,a total of 23 eligible patients were selected,13 patients were distributed to BuMA Supreme group and another 10 patients to Xience Prime group.The median time interval from implation to OCT examination was 33 days.There were statistically significant differences in the number of patients with diabetes at baseline(p=0.039).There were no significant differences in age,gender,days of follow-up,other underlying diseases,serum creatinine,fasting blood glucose,total cholesterol,triglycerides,low-density lipoprotein cholesterol,vascular disease site,length of vascular lesions,reference lumen diameter,minimum lumen diameter,stent diameter and stent length.Altogether,we analyzed 829 cross-sections and 8009 stent struts.BuMA Supreme group:437 cross-sections and 4478 stent struts,Xience Prime group:392 cross-sections and 3531 stent struts.OCT show that there was significant difference between BuMA Supreme group and Xience Prime group in the rate of coverage of stent struts(99.4% vs.98.3%,p<0.001),the complete coverage of struts(86.2% vs.74.7%,p<0.001),incomplete coverage of struts(13.2%vs.23.6%,p<0.001),the appearance of bare struts(13.2% vs.23.6%,p<0.001),the malapposed struts(3.7% vs.7%,p<0.001),the average thickness of neointimal above struct(0.07±0.04 mm vs.0.05±0.03 mm,p<0.001).Conclusion:Compared with the Xience Prime stent,the BuMA Supreme stent had a higher endothelialization rate and more completely endothelialized struts in high bleeding risk patients,so is the thickness of intimal hyperplasia on the struts.