***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: Background — Percutaneous coronary interventions in patients with chronic kidney disease have shown suboptimal results . Drug-eluting stents ( DES ) might reduce the rate of target vessel revascularization in comparison with bare-metal stents ( BMS ) in patients with chronic kidney disease . However , given the multiple concomitant individual variables present in such patients , the comparison of neointimal growth after percutaneous coronary intervention is complex and difficult to assess . Methods and Results — R and omized Comparison of Xience V and Multi-Link Vision Coronary Stents in the Same Multivessel Patient with Chronic Kidney Disease ( RENAL-DES ) was a prospect i ve , r and omized , multicenter study to directly compare the efficacy in the prevention of clinical restenosis of everolimus-eluting stent ( Xience V ) and BMS with an identical design ( Multi-Link Vision ) , both implanted in the same patient with multivessel coronary artery disease and chronic kidney disease ( estimated glomerular filtration rate < 60 mL/min ) . The primary end point of the study was the ischemia-driven target vessel revascularization as detected with myocardial scintigraphy at 12 months . In 215 patients , 512 coronary vessels were successfully treated with the r and omly assigned DES ( n=257 ) or BMS ( n=255 ) . At 1 year , the rate of ischemia-driven target vessel revascularization for DES and BMS groups was 2.7 % ( 95 % confidence interval , 1.1%–5.6 % ) and 11.4 % ( 95 % confidence interval , 7.8 % to 16 % ) , respectively , P<0.001 . For the multivariate analysis , independent predictors of the ischemia-driven target vessel revascularization were BMS implantation ( odds ratio , 4.95 ; 95 % confidence interval , 2.1–11.6 ; P<0.001 ) and vessel size ( odds ratio , 0.32 ; 95 % confidence interval , 0.1–0.7 ; P=0.006 ) . Conclusions — This is the first r and omized trial showing a reduction of clinical restenosis with a new-generation DES in comparison with a BMS of equal design , in patients who have chronic kidney disease with multivessel coronary artery disease . Clinical Trial Registration — URL : http:// clinical trials.gov . Unique identifier : NCT00818792 Background Chronic kidney disease ( CKD ) is strongly associated with adverse outcomes after percutaneous coronary intervention ( PCI ) . There are limited data on the effectiveness of drug-eluting stents ( DES ) in patients with CKD . Methodology /Principal Findings Of 3,752 consecutive patients enrolled in the Guthrie PCI Registry between 2001 and 2006 , 436 patients with CKD - defined as a creatinine clearance < 60 mL/min - were included in this study . Patients who received DES were compared to those who received bare metal stents ( BMS ) . Patients were followed for a mean duration of 3 years after the index PCI to determine the prognostic impact of stent type . Study end-points were all-cause death , myocardial infa rct ion ( MI ) , target vessel revascularization ( TVR ) , stent thrombosis ( ST ) and the composite of major adverse cardiovascular events ( MACE ) , defined as death , MI or TVR . Patients receiving DES in our study , by virtue of physician selection , had more stable coronary artery disease and had lower baseline risk of thrombotic or restenotic events . Kaplan-Meier estimates of proportions of patients reaching the end-points were significantly lower for DES vs. BMS for all-cause death ( p = 0.0008 ) , TVR ( p = 0.029 ) and MACE ( p = 0.0015 ) , but not MI ( p = 0.945 ) or ST ( p = 0.88 ) . Multivariable analysis with propensity adjustment demonstrated that DES implantation was an independent predictor of lower rates of all-cause death ( hazard ratio [ HR ] 0.48 , 95 % confidence interval [ CI ] 0.25–0.92 ) , TVR ( HR 0.50 , 95 % CI 0.27–0.94 ) and MACE ( HR 0.62 , 95 % CI 0.41–0.94 ) . Conclusions In a contemporary PCI registry , selective use of DES in patients with CKD was safe and effective in the long term , with lower risk of all-cause death , TVR and MACE and similar risk of MI and ST as compared with BMS . The mortality benefit may be a result of selection bias and residual confounding , or represent a true finding ; a hypothesis that warrants clarification by r and omized clinical trials Background —An observational study determining the long-term impact of  chronic kidney disease ( CKD )  on patients undergoing percutaneous coronary intervention at a tertiary cardiac referral center . CKD is associated with poor in-hospital outcomes after percutaneous coronary intervention , but its effect beyond 1 year , particularly in the drug-eluting stent ( DES ) era , has not been reported . Methods and Results —Baseline creatinine was available for 11 953 patients entered into a prospect i ve registry ( April 2000 to September 2007 ) . Patients were stratified : those with or without at least moderate CKD ( creatinine clearance , < 60 mL/min ) . Follow-up data were obtained through linkage to a provincial registry . Kaplan – Meier analysis was performed . Cox multiple-regression analysis identified independent predictors of late mortality and major adverse cardiac events ( MACE ) and examined the association between DES use and late outcomes in the presence or absence of CKD . CKD was present in 3070 patients ( 25.7 % ) . In-hospital mortality and MACE were significantly increased in CKD ( 3.34 % versus 0.44 % , P<0.001 and 5.73 % versus 2.2 % , P<0.001 ) . Survival and MACE-free survival at 7 years were reduced ( 64.5±1.4 % versus 89.4±0.5 % , P<0.001 ; 44.0±1.4 % versus 63.4±0.8 % , P<0.001 ) . CKD was an independent predictor of late mortality and MACE ( hazard ratio [ HR ] : 2.18 , CI : 1.90 to 2.49 , P<0.0001 ; HR : 1.37 , CI : 1.25 to 1.49 , P<0.0001 ) . DES use was associated with a significant reduction in both ( HR : 0.71 , CI : 0.60 to 0.83 , P<0.0001 ; HR : 0.70 , CI : 0.63 to 0.78 , P<0.0001 ) . In patients with CKD , DES use was associated with reduced revascularization ( HR : 0.68 , CI : 0.53 to 0.88 , P=0.004 ) and reduced MACE ( HR : 0.81 , CI : 0.69 to 0.95 , P=0.011 ) but not reduced mortality ( HR : 0.85 , CI : 0.69 to 1.05 , P=0.1 ) . Conclusion —In a large registry of “ all comers ” for percutaneous coronary intervention , CKD was an independent predictor of adverse late outcomes . DES use may be associated with improved long-term outcomes in this high-risk cohort , but further prospect i ve studies are required Background and Objectives Chronic kidney disease ( CKD ) is associated with poor outcomes after  percutaneous coronary intervention  ( PCI ) . We sought to compare different coronary stents used during primary PCI in patients with ST-elevation myocardial infa rct ion ( STEMI ) and CKD . Subjects and Methods We selected 2408 consecutive STEMI patients with CKD ( estimated glomerular filtration rate < 60 mL/min/1.73 m2 ) undergoing primary PCI  and divided them into 5 groups based on the type of stent implanted : 1 ) bare metal stent ( BMS ) , 2 ) paclitaxel-eluting stent ( PES ) , 3 ) sirolimus-eluting stent ( SES ) , 4 ) zotarolimus-eluting stent ( ZES ) , or 5 ) everolimus-eluting stent ( EES ) . The study endpoint was the number of major adverse cardiac events ( MACE ) at 12 months . Results There was no significant difference in the incidence of 12-month myocardial infa rct ion , target lesion revascularization , or target vessel revascularization between stent groups ; however , the overall rate of repeat revascularization differed significantly between groups . All-cause death differed significantly among the groups . The incidence of 12-month MACE in BMS , PES , SES , ZES , and EES was 8.3 % , 9.8 % , 8.6 % , 5.5 % , and 2.6 % , respectively ( p<0.001 ) . Kaplan-Meier analysis did not show a significant differences in 12-month MACE-free survival among the groups ( log-rank p=0.076 ) . This finding remained the same after adjusting for multiple confounders ( p=0.147 ) . Conclusion Any of the 5 stents can be used to treat STEMI patients with CKD undergoing primary PCI ; all have similar risk of 12-month MACE . This result is hypothesis-generating and warrants further evaluation with a long-term r and omized study To assess whether moderate‐to‐severe CKD is a treatment modifier for benefit or harm in patients r and omly allocated to 24‐month versus 6‐month DAPT OBJECTIVES This study sought to investigate the impact of  chronic kidney disease ( CKD ) in patients undergoing percutaneous coronary intervention ( PCI ) for ST-segment elevation myocardial infa rct ion ( STEMI ) with different antithrombotic strategies . BACKGROUND CKD is associated with increased risk of adverse ischemic and hemorrhagic events after primary PCI for STEMI . METHODS HORIZONS-AMI ( Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infa rct ion ) trial was a multicenter , international , r and omized trial comparing bivalirudin monotherapy or heparin plus a glycoprotein IIb/IIIa inhibitor ( GPI ) during primary PCI in STEMI . CKD , defined as creatinine clearance < 60 ml/min , was present at baseline in 554 of 3,397 patients ( 16.3 % ) . Patients were followed for 3 years . Net adverse cardiac event ( NACE ) was defined as the composite of death , reinfa rct ion , ischemia-driven target vessel revascularization ( TVR ) , stroke or non-coronary artery bypass grafting (CABG)-related major bleeding . RESULTS Patients with CKD compared with patients without had higher rates of NACE ( 41.4 % vs. 23.8 % , p < 0.0001 ) , death ( 18.7 % vs. 4.4 % , p < 0.0001 ) , and major bleeding ( 19.3 % vs. 6.7 % , p < 0.0001 ) . Multivariable analysis identified baseline creatinine as an independent predictor of death at 3 years ( hazard ratio : 1.51 , 95 % confidence interval : 1.21 to 1.87 , p < 0.001 ) . Patients with CKD r and omized to bivalirudin monotherapy versus heparin plus GPI had no significant difference in major bleeding ( 19.0 % vs. 19.6 % , p = 0.72 ) or death ( 19.0 % vs. 18.4 % , p = 0.88 ) at 3 years . In patients with CKD , there was no difference in the rates of TVR in bare-metal stents ( BMS ) versus drug-eluting stents ( DES ) at 3 years ( 14.1 % vs. 15.1 % , p = 0.8 ) . CONCLUSIONS STEMI patients with CKD have significantly higher rates of death and major bleeding compared with those without CKD . In patients with CKD , there appears to be no benefit of bivalirudin compared with heparin + GPI , or DES versus BMS during primary PCI in improving clinical outcomes Scarce and conflicting evidence exists on whether clopidogrel is effective and whether dual antiplatelet treatment ( DAPT ) is safe in patients with acute coronary syndrome and chronic kidney disease ( CKD ) . To study this , we performed an observational , prospect i ve , multicenter cohort study of 36,001 patients of the SWEDEHEART registry . The exposure was DAPT prolonged after 3 months versus DAPT stopped at 3 months in consecutive patients with acute coronary syndrome and known serum creatinine .  DAPT duration with clopidogrel and aspirin was assessed by dispensed tablets . CKD stages were classified according to estimated glomerular filtration rate ( eGFR ) . Study outcomes were 1 ) the composite of death , myocardial infa rct ion , or ischemic stroke ; 2 ) bleeding ; or 3 ) the aggregate of these two outcomes within day 11 
    Output:
    
We also found a gradient between 1st and 2nd generation DES , through BMS .
Conclusions  DES in CKD patients undergoing PCI were superior to BMS in reducing major adverse clinical events .
This was possibly explained , by a lower risk of stent-related events as ST and TVR or TLR .
Second , compared to 1st generation DES may furtherly reduce clinical events