percutaneous coronary intervention ( pci ) has become the most widely used method to treat patients with coronary artery disease . the introduction of drug - eluting stents ( dess ) led the interventional cardiology to a new era , in which the pci became an alternative to coronary artery bypass surgery even in complex lesions . paclitaxel , sirolimus , and its derivatives were the most widely used anti - proliferative drugs of des and their efficacy in inhibiting smooth muscle cell proliferation had been verified in several clinical trials . however , several studies found that both sirolimus and paclitaxel lead to delayed arterial healing and endothelial dysfunction , which could be the major reason of the increasing late and very late stent thrombosis ( vlst ) events . a new des platform combining the approved 316l stainless stent platform with a novel anti - proliferative agent , arsenic trioxide , and a biodegradable poly - l - lactic acid ( plla ) polymer has been developed . arsenic trioxide , a chemotherapy drug that has been widely used in the treatment of acute promyelocytic leukemia ( apl ) , was proved to inhibit cell growth and induce cell apoptosis . our previous study had proved this stent system significantly suppressed in - stent restenosis by reducing proliferation and inducing apoptosis of vascular smooth muscle cells ( vsmcs ) compared to uncoated stents in a rabbit iliac artery injury model . in addition , it also inhibits local inflammatory reactions , which suppresses the endothelial healing . the purpose of this study was to investigate whether the aes ( amsinomed medical company , beijing , china ) is effective and safe as an alternative to current des in human . the firebird ses ( microport corporation , shanghai , china ) , a widely used des in china , is selected as the comparison . the trial was a multicenter , perspective , randomized controlled trial designed to compare clinical and angiographic outcomes between arsenic trioxide - eluting stents ( aess ) and sirolimus - eluting stents ( ses ) [ figure 1 ] . the study protocol was approved by the ethics committee at each participating center and was conducted according to the principles of the declaration of helsinki regarding investigations in humans . patient flow chart . aes : arsenic trioxide - eluting stent(s ) ; ses : sirolimus - eluting stent(s ) ; tvf : target vessel failure ; lll : late luminal loss . patients 18 and < 80 years of age were eligible for enrollment if they showed symptoms of angina pectoris and/or signs of ischemia or angina and met the main inclusion criteria of coronary angiography : ( 1 ) lesion length 37 mm ; ( 2 ) reference vessel diameter ( rvd ) 2.04.0 mm ; ( 3 ) a diameter stenosis 70% or total occlusion lesion . no restriction was applied to the total number of treated lesions , treated vessels , or number of stents implanted . exclusion criteria included cardiac shock , congenital heart disease , severe valvular disease , left ventricular ejection fraction < 30% , allergy to antiplatelet drugs , heparin , stainless steel , contrast agents , surgery in 6 weeks , acute myocardial infarction ( mi ) within 2 weeks , transient ischemic attack or stroke within 7 days , wbc < 4.0  10/l , pbc < 100  10/l , 1.5 times higher than normal value of alanine aminotransferases , aspartate aminotransferase , or alkaline phosphate , using thrombolytic agents or gpiib / iiia antagonists in 1 week , gastrointestinal and fundus bleeding within 6 months , true bifurcation lesion with side branch diameter > 2.00 mm , life expectancy < 1 year , stented target lesion , inability or unwillingness to comply with all protocol - required procedure , and a positive pregnancy test within 24 h before enrollment . patients were assigned a number from a randomization sequence generated by sas 9.1 ( sas institute , north carolina , usa ) and maintained by a statistician who was blinded to the treatments . aes were available in diameters of 2.0 , 2.5 , 2.75 , 3.0 , 3.5 , and 4.0 mm and in lengths of 8 , 13 , 17 , 22 , 27 , 33 , and 37 mm . both the aes and ses were expanded to achieve < 20% residual stenosis by visual estimate in the treated segment , with a combination of the stent deployment balloon and at the operators discretion , subsequent postdilatation balloons . patients who were not on long - term antiplatelet or aspirin therapy were required to receive a loading dose of aspirin ( 300 mg / d ) and clopidogrel bisulfate ( 300 mg ) at least 24 h before the procedure , followed by 75 mg / d of clopidogrel after procedure . at discharge , patients were maintained on at least 100 mg / d of aspirin and 75 mg / d of clopidogrel for at least 6 months . heparin was administered throughout the procedure to maintain an activated clotting time 230 s. all patients were scheduled to undergo a repeated angiography at 9 months . clinical follow - up was performed at 1 , 3 , 6 , 9 , 18 , 24 months by telephone . at follow - up , patients were specifically questioned regarding any adverse events or angina symptoms or other interventional therapy . the primary end point was target vessel failure ( tvf ) , a composite of cardiac death , target vessel mi , clinically driven target vessel revascularization ( defined as a repeated revascularization due to either a > 50% restenosis in the treated lesion with symptoms of ischemia or for a > 70% restenosis with or without symptoms within the entire major coronary vessel proximal and distal to a target lesion , including upstream and downstream branches and the target lesion itself ) . the secondary endpoints included late luminal loss ( lll ) , procedure success rate , in - stent restenosis rate , target lesion revascularization ( tlr ) , all - cause death , cardiac death or mi . the lll was defined as the difference between postprocedural and 9-month angiography follow - up minimal lumen diameter . the quantitative coronary angiography measurements were obtained for both the stented segment (  in - stent  ) and a segment covering the stented length as well as 5-mm distal and proximal margins (  in - segment  ) . tlr was defined as any ischemia - driven repeat pci of the target lesion or bypass surgery of the target vessel . cardiac death was defined as death due to any of the following : acute mi ; cardiac perforation / pericardial tamponade ; arrhythmia or conduction abnormality . the trial was designed to test the efficacy of aes compared with ses with respect to the primary endpoint of tvf . all primary and secondary endpoints were adjudicated by the independent and blinded clinical event committee . the objective of the study was to assess efficacy of aes compared with the ses with regard to the primary endpoint , tvf . based on the previous studies , we expect a mean in - stent lll of 0.40 mm firebird ses . the standard deviation ( sd ) for lll was presumed to be 0.45 mm , so the noninferiority margin was set at 0.15 mm ( equaling 35% of 0.45 mm ) . based on these assumptions , 102 patients per treatment group needed to be analyzed to provide a statistical power of 0.80 at an alpha level of 0.05 . continuous variables are presented as mean  sd , and categorical variables are presented as counts and percentages . categorical variables were compared using chi - square and fisher 's exact tests while continuous variables were compared using student 's t - test . survival and event - free status were assessed using the methods of kaplan  meier . all statistical analyses were performed by a physician with the use of r version 3.0.2 ( http://www.r-project.org ) . all reported p values were two - sided , and p < 0.05 were regarded as statistically significant . the trial was a multicenter , perspective , randomized controlled trial designed to compare clinical and angiographic outcomes between arsenic trioxide - eluting stents ( aess ) and sirolimus - eluting stents ( ses ) [ figure 1 ] . the study protocol was approved by the ethics committee at each participating center and was conducted according to the principles of the declaration of helsinki regarding investigations in humans . patient flow chart . aes : arsenic trioxide - eluting stent(s ) ; ses : sirolimus - eluting stent(s ) ; tvf : target vessel failure ; lll : late luminal loss . patients 18 and < 80 years of age were eligible for enrollment if they showed symptoms of angina pectoris and/or signs of ischemia or angina and met the main inclusion criteria of coronary angiography : ( 1 ) lesion length 37 mm ; ( 2 ) reference vessel diameter ( rvd ) 2.04.0 mm ; ( 3 ) a diameter stenosis 70% or total occlusion lesion . no restriction was applied to the total number of treated lesions , treated vessels , or number of stents implanted . exclusion criteria included cardiac shock , congenital heart disease , severe valvular disease , left ventricular ejection fraction < 30% , allergy to antiplatelet drugs , heparin , stainless steel , contrast agents , surgery in 6 weeks , acute myocardial infarction ( mi ) within 2 weeks , transient ischemic attack or stroke within 7 days , wbc < 4.0  10/l , pbc < 100  10/l , 1.5 times higher than normal value of alanine aminotransferases , aspartate aminotransferase , or alkaline phosphate , using thrombolytic agents or gpiib / iiia antagonists in 1 week , gastrointestinal and fundus bleeding within 6 months , true bifurcation lesion with side branch diameter > 2.00 mm , life expectancy < 1 year , stented target lesion , inability or unwillingness to comply with all protocol - required procedure , and a positive pregnancy test within 24 h before enrollment . patients were assigned a number from a randomization sequence generated by sas 9.1 ( sas institute , north carolina , usa ) and maintained by a statistician who was blinded to the treatments . aes were available in diameters of 2.0 , 2.5 , 2.75 , 3.0 , 3.5 , and 4.0 mm and in lengths of 8 , 13 , 17 , 22 , 27 , 33 , and 37 mm . both the aes and ses were expanded to achieve < 20% residual stenosis by visual estimate in the treated segment , with a combination of the stent deployment balloon and at the operators discretion , subsequent postdilatation balloons . patients who were not on long - term antiplatelet or aspirin therapy were required to receive a loading dose of aspirin ( 300 mg / d ) and clopidogrel bisulfate ( 300 mg ) at least 24 h before the procedure , followed by 75 mg / d of clopidogrel after procedure . at discharge , patients were maintained on at least 100 mg / d of aspirin and 75 mg / d of clopidogrel for at least 6 months . clinical follow - up was performed at 1 , 3 , 6 , 9 , 18 , 24 months by telephone . at follow - up , patients were specifically questioned regarding any adverse events or angina symptoms or other interventional therapy . the primary end point was target vessel failure ( tvf ) , a composite of cardiac death , target vessel mi , clinically driven target vessel revascularization ( defined as a repeated revascularization due to either a > 50% restenosis in the treated lesion with symptoms of ischemia or for a > 70% restenosis with or without symptoms within the entire major coronary vessel proximal and distal to a target lesion , including upstream and downstream branches and the target lesion itself ) . the secondary endpoints included late luminal loss ( lll ) , procedure success rate , in - stent restenosis rate , target lesion revascularization ( tlr ) , all - cause death , cardiac death or mi . the lll was defined as the difference between postprocedural and 9-month angiography follow - up minimal lumen diameter . the quantitative coronary angiography measurements were obtained for both the stented segment (  in - stent  ) and a segment covering the stented length as well as 5-mm distal and proximal margins (  in - segment  ) . tlr was defined as any ischemia - driven repeat pci of the target lesion or bypass surgery of the target vessel . cardiac death was defined as death due to any of the following : acute mi ; cardiac perforation / pericardial tamponade ; arrhythmia or conduction abnormality . the trial was designed to test the efficacy of aes compared with ses with respect to the primary endpoint of tvf . all primary and secondary endpoints were adjudicated by the independent and blinded clinical event committee . the objective of the study was to assess efficacy of aes compared with the ses with regard to the primary endpoint , tvf . based on the previous studies , we expect a mean in - stent lll of 0.40 mm firebird ses . the standard deviation ( sd ) for lll was presumed to be 0.45 mm , so the noninferiority margin was set at 0.15 mm ( equaling 35% of 0.45 mm ) . based on these assumptions , 102 patients per treatment group needed to be analyzed to provide a statistical power of 0.80 at an alpha level of 0.05 . continuous variables are presented as mean  sd , and categorical variables are presented as counts and percentages . categorical variables were compared using chi - square and fisher 's exact tests while continuous variables were compared using student 's t - test . survival and event - free status were assessed using the methods of kaplan  meier . all statistical analyses were performed by a physician with the use of r version 3.0.2 ( http://www.r-project.org ) . all reported p values were two - sided , and p < 0.05 were regarded as statistically significant . between july 2009 and january 2010 , 212 patients and 265 lesions were enrolled into this randomized study at eight sites across china . at 24 months , clinical follow - up was available for 105 patients in aes group and 103 patients in ses group . baseline , procedural , and lesion characteristics of the two randomized groups of patients were similar . the average age of the patients was 58.6 years , and 69.8% of enrolled patients were male . all of them suffered a history of angina pectoris and presented with an abnormal electrocardiogram and abnormal ultrasonic cardiogram [ table 1 ] . of a total of 265 treated lesions , approximately half of them are type b2/c lesions with mean rvds of 3.01  0.36 mm and lesion lengths of 19.97  8.20 mm ( aes ) and 19.52  8.13 mm ( ses ) . there was no significant difference between the baseline target lesions , but more severe diameter stenosis was observed in aes group ( 87.09  8.86% vs. 83.36  9.00% , p = 0.001 ) [ table 2 ] . baseline patient characteristics ecg : electrocardiogram ; ucg : ultrasound cardiogram ; aes : arsenic trioxide - eluting stent ; ses : sirolimus - eluting stent . lesion and procedure characteristics ds : diameter stenosis ; rvd : reference vessel diameter ; aes : arsenic trioxide - eluting stent ; ses : sirolimus - eluting stent ; acc : american college of cardiology ; aha : american heart association . in both groups , a certain proportion of patients were treated with balloon predilatation ( 62.9% aes vs. 51.4% ses ) and postdilatation ( 25.7% aes vs. 32.7% ses ) [ table 2 ] . average stent diameter ( 3.01  0.35 mm aes vs. 3.00  0.43 mm ses ) and mean stent length ( 21.22  5.77 mm aes vs. 22.12  6.59 mm ses ) have been illustrated in table 3 . stent implantation data aes : arsenic trioxide - eluting stent ; ses : sirolimus - eluting stent . the follow - up rate was more than 80% through the 24-month follow - up . the primary endpoint tvf in aes group was stable ( 6.67% ) , but an increasing trend was observed in ses group ( 1.87%5.83% ) . no significant difference between two groups was concluded . all cause death rate , as well as cardiac death or mi rate ( 0 vs. 3.88% , p = 0.058 ) at 24 months , was lower in aes group compared with ses group ( 0 vs. 4.85% , other adverse events including tlr , cerebral hemorrhage , noncardiac death , stent thrombosis , and angina pectoris were similar in both groups [ table 4 ] . 85 patients with 101 lesions in aes group ( 80.95% ) and 57 patients with 62 lesions in ses group ( 53.27% ) underwent angiographic follow - up at 9 months after stent implantation . in - segment late loss was 0.20  0.22 mm in aes group and 0.10  0.35 mm ses group . in - stent late loss was 0.29  0.52 mm in aes group and 0.10  0.25 mm in ses group . the difference in in - stent late loss between two groups was 0.18 mm ( 95% confidence interval : 0.0770.313 mm ) , which was larger than the noninferiority margin as 0.15 mm . binary in - stent and in - segment restenosis rate were not different between the two groups ; however , diameter stenosis was statistically greater in aes group than ses group for both in - stent ( 21.05%  18.70% vs. 12.01%  16.26% , p = 0.002 ) and in - segment ( 22.86%  11.34% vs. 17.83%  13.59% , p = 0.012 ) [ table 5 ] . clinical outcomes , n ( % ) tvf : target vessel failure ; mi : myocardial infarction ; tlr : target lesion revascularization ; st : stent thrombosis ; aes : arsenic trioxide - eluting stent ; ses : sirolimus - eluting stent . nine - month angiographic follow - up results aes : arsenic trioxide - eluting stent ; ses : sirolimus - eluting stent . between july 2009 and january 2010 , 212 patients and 265 lesions were enrolled into this randomized study at eight sites across china . at 24 months , clinical follow - up was available for 105 patients in aes group and 103 patients in ses group . baseline , procedural , and lesion characteristics of the two randomized groups of patients were similar . the average age of the patients was 58.6 years , and 69.8% of enrolled patients were male . all of them suffered a history of angina pectoris and presented with an abnormal electrocardiogram and abnormal ultrasonic cardiogram [ table 1 ] . of a total of 265 treated lesions , approximately half of them are type b2/c lesions with mean rvds of 3.01  0.36 mm and lesion lengths of 19.97  8.20 mm ( aes ) and 19.52  8.13 mm ( ses ) . there was no significant difference between the baseline target lesions , but more severe diameter stenosis was observed in aes group ( 87.09  8.86% vs. 83.36  9.00% , p = 0.001 ) [ table 2 ] . baseline patient characteristics ecg : electrocardiogram ; ucg : ultrasound cardiogram ; aes : arsenic trioxide - eluting stent ; ses : sirolimus - eluting stent . lesion and procedure characteristics ds : diameter stenosis ; rvd : reference vessel diameter ; aes : arsenic trioxide - eluting stent ; ses : sirolimus - eluting stent ; acc : american college of cardiology ; aha : american heart association . in both groups , a certain proportion of patients were treated with balloon predilatation ( 62.9% aes vs. 51.4% ses ) and postdilatation ( 25.7% aes vs. 32.7% ses ) [ table 2 ] . average stent diameter ( 3.01  0.35 mm aes vs. 3.00  0.43 mm ses ) and mean stent length ( 21.22  5.77 mm aes vs. 22.12  6.59 mm ses ) have been illustrated in table 3 . stent implantation data aes : arsenic trioxide - eluting stent ; ses : sirolimus - eluting stent . the follow - up rate was more than 80% through the 24-month follow - up . the primary endpoint tvf in aes group was stable ( 6.67% ) , but an increasing trend was observed in ses group ( 1.87%5.83% ) . no significant difference between two groups was concluded . all cause death rate , as well as cardiac death or mi rate ( 0 vs. 3.88% , p = 0.058 ) at 24 months , was lower in aes group compared with ses group ( 0 vs. 4.85% , p = 0.028 ) . other adverse events including tlr , cerebral hemorrhage , noncardiac death , stent thrombosis , and angina pectoris were similar in both groups [ table 4 ] . 85 patients with 101 lesions in aes group ( 80.95% ) and 57 patients with 62 lesions in ses group ( 53.27% ) underwent angiographic follow - up at 9 months after stent implantation . in - segment late loss was 0.20  0.22 mm in aes group and 0.10  0.35 mm ses group . in - stent late loss was 0.29  0.52 mm in aes group and 0.10  0.25 mm in ses group . the difference in in - stent late loss between two groups was 0.18 mm ( 95% confidence interval : 0.0770.313 mm ) , which was larger than the noninferiority margin as 0.15 mm . binary in - stent and in - segment restenosis rate were not different between the two groups ; however , diameter stenosis was statistically greater in aes group than ses group for both in - stent ( 21.05%  18.70% vs. 12.01%  16.26% , p = 0.002 ) and in - segment ( 22.86%  11.34% vs. 17.83%  13.59% , p = 0.012 ) [ table 5 ] . clinical outcomes , n ( % ) tvf : target vessel failure ; mi : myocardial infarction ; tlr : target lesion revascularization ; st : stent thrombosis ; aes : arsenic trioxide - eluting stent ; ses : sirolimus - eluting stent . nine - month angiographic follow - up results aes : arsenic trioxide - eluting stent ; ses : sirolimus - eluting stent . the main findings of the current study were as below : ( 1 ) the efficacy of aes and ses was similar over the follow - up period , with no significant difference observed in the incidence of tvf . ( 2 ) aes group has a significant lower rate of all - cause death than ses group , but not in lll and in - stent restenosis . although both ses and paclitaxel - eluting stents have greatly reduced in - stent restenosis , the first generation of des has led to concern for increased risk of late and vlst due to delayed arterial healing . in spite of the unclear mechanism , both sirolimus and paclitaxel were thought to play an important role on both delayed healing and endothelial dysfunction , which may cause the increasing risk of lst . despite the lower rate of late adverse events and better endothelial function of the second generation des , the anti - proliferative drugs they used , such as zotarolimus , everolimus , and biolimus a9 , were still sirolimus derivatives . all of them are specific inhibitors of the mammalian target of rapamycin ( mtor ) signaling pathway , which controls protein synthesis and has an important role in modulating cell division in response to mitogenic stimuli . the inhibition of mtor pathway could greatly inhibit the proliferation of vsmc , however it could also inhibit the proliferation and migration of endothelial cell ( ec ) , which causes delayed healing and endothelial dysfunction . hence , the attempt to using a novel drug , which has diverse pathways to inhibiting vsmc proliferation , could possibly reduce the damage to ecs , and leads to better clinical outcomes . arsenic trioxide , a natural substance that was used in the treatment of apl , also proved to induce cellular apoptosis in vsmcs through intracellular reactive oxygen species formation and free ca increase in vitro . previous study suggested that the aes could significantly suppress the in - stent restenosis in animal models as well . besides , the dosage of arsenic trioxide in our eluting stent was only 40 g , which was much less than the safe amount administered systemically ( 0.15 mgkgday ) . in our study , no adverse events correlated with arsenic trioxide toxicity occurred . though further observation for long - term safety is needed , aes was safe to use on the basis of current evidence . the primary end point tvf was similar between two groups in 24-month follow - up ( 6.67% vs. 5.83% , p = 0.802 ) . we note that all tvf ( actually all tlr ) events occurred within the 9-month follow - up in aes group , in contrast to the gradually increasing incidence in ses group , which could be explained as  late catch - up  phenomenon . although early observation of tlr showed possible greater neointimal hyperplasia with aes , no events after 12 months indicated the potential advantage of aes in long - term efficacy . notably , all - cause death ( 0 vs. 4.85% , p = 0.028 ) and cardiac death or mi events ( 0 vs. 3.88% , p = 0.058 ) , mostly happening after 1 year , were lower in aes group . among the four cardiac death events , three of them were attributed to definite or probable late or vlst , although there were no significant differences between two groups . possible explanation of this finding may be the comparative lower toxicity of arsenic trioxide to ec and rapid elution of the drug from a biodegradable polymer . although des remarkably reduced restenosis and repeated revascularization , the occurrence of late events , such as lst and vlst , was the major limitation of des . the reduction of cardiac death and mi , which seemed to be mainly driven by a reduction in vlst , could greatly shift the risk / benefit balance in favor of des . hence , the less long - term adverse events could be a potential advantage of aes over ses . in - stent lll at 9-month angiographic follow - up was significantly higher in patients treated with aes as compared those with ses ( 0.29  0.52 mm vs. 0.10  0.25 mm , p = 0.008 ) , as well as in - segment lll ( 0.20  0.22 mm vs. 0.10  0.35 mm , p = 0.026 ) . the reasons for higher lll observed with aes in this trial compared with ses are not completely understood . it might be due to differences in biological activity of arsenic trioxide compared with sirolimus , although in vitro cell culture experiments and animal studies would suggest at least equivalent potencies in suppressing smooth muscle cell proliferation and even additionally inducing cell apoptosis . another potential reason for the difference is the too short elution time of arsenic trioxide from the plla . in previous study , arsenic trioxide could reach a plateau after 8 days in contrast to 14 days of paclitaxel in vitro . more rapid elution time leads to insufficient tissue exposure to the therapeutic agents , resulting inadequate suppression of inflammation and intimal hyperplasia induced by injury responses . the endeavor zotarolimus - eluting stent ( e - zes ) , which also has a short release duration , suffered an even higher in - stent lll of around 0.60 mm and higher tlr rate compared to ses . hence , it has reason to believe that the higher lll of the aes group is caused by the quick release of drugs and polymers . third , low rate of angiographic follow - up in ses group ( 53.27% ) may result in an overestimate of the difference between two groups . despite the higher restenosis rate , the lower late events and stable tlr rate let us consider aes as a potential interestingly , in spite of the higher tlr of e - zes compared with des in the 1 year , the rates of cardiac death / mi , tlr , and definite / probable stent thrombosis were significantly lower with e - zes in the 5-year time frame . hence , the long - term efficacy and safety of aes are promising , and the attempt to using novel arsenic trioxide as an alternative to traditional sirolimus derivatives remains bright prospects . first , patients included in this study were selected strictly by angiographic and clinical characteristics , so the study population may not represent the real - world patients with coronary artery diseases , including mi . meanwhile , the history of some risk factors such as diabetes was not included in this study , and it may cause bias of the result . second , the angiographic follow - up rate was unsatisfactory in ses group and may have resulted in an underestimation of the occurrence of angiographic restenosis in a controlled group . in addition , around 20% of patients were lost to clinical follow - up during the 270 days , and it may also affect the final conclusion . third , ivus , oct , and other intracoronary imaging examinations were not used to evaluate the stent - treated lesion . besides that , the trial is a lack of a long - term angiographic endpoint , which can be used to confirm the long - term safety of aes . prospective observational and controlled clinical trials with a larger size may contribute to our understanding of the performance of aes and may provide insight into outcomes of the real - world use of aes . the comparison group used in this study enrolled patients using the first - generation ses , which was in routine clinical use when the study was undertaken while now it is used relatively infrequently in clinical practice . the 2-year follow - up of the randomized controlled trial demonstrates the efficacy and safety of aes compared with ses for the treatment of de novo coronary lesions . despite the higher lll , aes group shows similar tvf rate and significant reduction of all - caused death rate .
background : despite great reduction of in - stent restenosis , first - generation drug - eluting stents ( dess ) have increased the risk of late stent thrombosis due to delayed endothelialization . 
 arsenic trioxide , a natural substance that could inhibit cell proliferation and induce cell apoptosis , seems to be a promising surrogate of sirolimus to improve des performance . 
 this randomized controlled trial was to evaluate the efficacy and safety of a novel arsenic trioxide - eluting stent ( aes ) , compared with traditional sirolimus - eluting stent ( ses).methods : patients with symptoms of angina pectoris were enrolled and randomized to aes or ses group . 
 the primary endpoint was target vessel failure ( tvf ) , and the second endpoint includes rates of all - cause death , cardiac death or myocardial infarction , target lesion revascularization ( tlr ) by telephone visit and late luminal loss ( lll ) at 9-month by angiographic follow-up.results:from july 2007 to 2009 , 212 patients were enrolled and randomized 1:1 to receive either aes or ses . at 2 years of follow - up , 
 tvf rate was similar between aes and ses group ( 6.67% vs. 5.83% , p = 0.980 ) . 
 frequency of all - cause death was significantly lower in aes group ( 0 vs. 4.85% , p = 0.028 ) . 
 there was no significant difference between aes and ses in frequency of tlr and in - stent restenosis , but greater in - stent lll was observed for aes group ( 0.29  0.52 mm vs. 0.10  0.25 mm , p = 0.008).conclusions : after 2 years of follow - up , aes demonstrated comparable efficacy and safety to ses for the treatment of de novo coronary artery lesions .