Factors Influencing In-Stent Restenosis After Percutaneous Coronary Intervention

Objectives:The number of stents implanted has been increasing year by year due to the rising morbidity of coronary artery disease(CAD).Although drug eluting stent(DES)could inhibit the hyperplasia of neointima,the in-stent restenosis(ISR)remains to be a large problem.Herein,in the present study,we tried to explore the risk factors of DES-ISR by retrospectively analyzing the clinical features,the procedural characteristics of coronary stent implantation and post-operative treatment.Methods:A total of 361 patients who received DES implantation at the Department of Cardiology,First Affiliated Hospital,Zhejiang University School of Medicine from January 2016 to December 2017 were enrolled.Patients were divided into two groups based on the results of coronary angiography:group in-stent restenosis(ISR)and group non-in-stent restenosis(NISR).In brief,ISR was defined as the reduced lumen area of the target vessel by over 50%after PCI(the proximal end and distal end,including the stent within 5 mm from the margin).Clinical baseline characteristics,coronary angiographic data,postoperative medication were recorded,followed by analysis with their correlation with DES-ISR.Results:Sixty of the 361 patients(16.6%)enrolled had ISR.The serum uric acid level was significantly higher in NISR group than that in ISR group(345.81±5.45 vs.318.16±10.07,P=0.038).The level of high density lipoprotein(HDL)in patients with diabetes mellitus in ISR group was significantly lower than that in those with diabetes mellitus in NISR group(0.84±0.04 vs.1.01±0.03,P<0.05)The smaller stent diameter and larger number of stent implantation were associated with a higher risk of ISR(diameter:2.85±0.65 vs.3.00±0.26;number:2.4±0.17 vs.1.78±0.05,P<0.05=.Patients with Sirolimus Eluting Stents(SES)and Everolimus Eluting Stents(EES)had similar incidence of ISR.However,the rates of ISR were significantly higher in those with Zotarolimus Eluting Stents(ZES)that those with SES and EES(P<0.05).Multivariate logistic regression analyses indicated that stent diameter(OR=0.284,0.134-0.600 mm),number of stent(OR=1.629,1.250-2.123)were independent risk factors for ISR after PCI(P<0.05),while uric acid level(OR=0.997,0.993-1.000)was a protective factor for ISRConclusion:Low level of HDL,multiple stent and small diameter of stent implanted might be associated with a high risk of ISR,while high level of serum uric acid might play a protective role to prevent the occurrence of ISR.ZES were not superior to SES or EES in reducing the incidence of ISR.In addition,extended follow-up time might be required to identify the presence of ISR at late stage.