Biodegradable Polymer Everolimus-eluting Stents Research Articles

Comparison of thrombogenicity in different types of drug-eluting stents during transition from DAPT to SAPT.

During the transition from dual antiplatelet therapy (DAPT) to single antiplatelet therapy (SAPT), previous studies have raised concerns about a rebound effect. We compared platelet and inflammatory cell adhesion on different types of stents in the setting of clopidogrel presence and withdrawal. In Experiment 1, three pigs were administered with DAPT, that is, clopidogrel and acetylsalicylic acid (ASA), for 7 days. Each animal underwent an extracorporeal carotid arteriovenous shunt model implanted with fluoropolymer-coated everolimus-eluting stent (FP-EES), biodegradable-polymer sirolimus-eluting stent (BP-SES), and biodegradable-polymer everolimus-eluting stents (BP-EES). In Experiment 2, two pigs were administered DAPT, clopidogrel was then withdrawn at day 7, and SAPT with ASA was continued for next 21 days. Then flow-loop experiments with the drawn blood from each time point were performed for FP-EES, BioLinx-polymer zotarolimus-eluting stents (BL-ZES), and BP-EES. The rebound effect was defined as the statistical increase of inflammation and platelet adhesion assessed with immunohistochemistry on the stent-strut level basis from baseline to day-14 or 28. Both experiments showed platelet adhesion value was highest in BP-EES, while the least in FP-EES during DAPT therapy. There was no increase in platelet or inflammatory cell adhesion above baseline values (i.e., no therapy) due to the cessation of clopidogrel on the stent-strut level. Monocyte adhesion was the least for FP-EES with the same trend observed for neutrophil adhesion. No evidence of rebound effect was seen after the transition from DAPT to SAPT. FP-EES demonstrated the most favorable antithrombotic and anti-inflammatory profile regardless of the different experimental designs.

Tissue responses to everolimus-eluting stents implanted in severely calcified lesions following atherectomy

Histopathological examination has revealed that stents on severely calcified plaques were associated with delayed vascular healing. Although atherectomy devices can increase the number of malapposed struts, tissue responses to implanted drug eluting stents in atherectomy patients remain largely unknown. This retrospective observational study included 30 patients who underwent atherectomy and everolimus-eluting stent (EES) deployment for severely calcified coronary lesions (biodegradable polymer EES (BP-EES), n = 15; durable polymer EES (DP-EES), n = 15). Optical coherence tomography was carried out at baseline and follow-up, and struts with acute stent malapposition (ASM) were categorized as struts on modified calcium (mod-Ca), non-modified calcium (non-mod-Ca), or non-calcium (non-Ca). Adequate vascular healing, defined as ASM resolution with neointimal coverage, was compared between the BP-EES and DP-EES groups. Multivariate linear regression analysis using a generalized estimated equation revealed that BP-EES use was associated with significantly better adequate vascular healing compared with DP-EES (odds ratio [OR]: 3.691, 95% confidence interval [CI] 1.175–11.592, P = 0.025). adequate vascular healing was associated with the underlying plaque morphology (mod-Ca vs non-mod-Ca: OR 2.833, 95% CI 1.491–5.384, P = 0.001; non-Ca vs non-mod-Ca: OR 1.248, 95% CI 0.440–3.543, P = 0.677). This study demonstrates that drug-eluting stent selection and calcium modification are possible factors affecting vascular healing of malapposed struts in severely calcified lesions.Graphical

Comparison of 6-Month and Prolonged Dual Antiplatelet Therapy after Percutaneous Coronary Intervention with Biodegradable Polymer Everolimus-Eluting Stent.

Background The optimal duration of dual antiplatelet therapy (DAPT) after biodegradable-polymer (BP) everolimus-eluting stent (EES) implantation remains uncertain. Methods This study analyzed 793 patients who underwent percutaneous coronary intervention (PCI) with BP-EES in 10 cardiovascular centers in Korea between July 2016 and January 2018. Using the prescription data at 6 months post-PCI, we divided these patients into two groups, namely, short-DAPT and prolonged-DAPT groups, which underwent DAPT for 6 and > 6 months of PCI, respectively. The primary endpoint, which included mortality, myocardial infarction, or target-vessel revascularization at 2 years, was compared by propensity score (PS) matching between the two groups. Results Out of the 793 patients, 283 matched pairs were identified by PS matching. Out of this matched population, 405 (71.6%) patients had an acute coronary syndrome. The primary endpoint did not differ in 2 years between the short-DAPT and prolonged-DAPT groups (7.5% vs. 8.3%; hazard ratio, 0.87; 95% confidential interval, 0.47–1.60; P = 0.648). Likewise, no difference was found regarding mortality, cardiac mortality, myocardial infarction, target-lesion failure, target-vessel failure, and bleeding events defined by the Bleeding Academic Research Consortium and Thrombolysis In the Myocardial Infarction classification. Meanwhile, one patient in the short-DAPT group had definite stent thrombosis at 364 days post-PCI. Subgroup analysis showed that several anatomical and procedural factors were not significantly related to DAPT duration. Most patients (77.4%) in both groups were prescribed clopidogrel at discharge. Conclusions In real-world patients undergoing PCI with BP-EES, the ischemic and bleeding endpoints demonstrated no difference between 6-month and prolonged (>6 months) DAPT.

Acute thrombogenicity of fluoropolymer coated stents versus competitive drug-eluting stents under single antiplatelet therapy

BackgroundRecent clinical studies have suggested the feasibility of 1-month dual antiplatelet therapy (DAPT) for patients receiving drug-eluting stent (DES). Although our previous ex-vivo swine arteriovenous (AV) shunt studies under low dose heparin treatment suggested superior thromboresistance of fluoropolymer-coated everolimus-eluting stent (FP-EES) when compared to other polymer-based DESs, the relative thromboresistance of different DESs under single antiplatelet therapy (SAPT) has never been examined. This study aimed to evaluate platelet adhesion under SAPT in competitive DESs in the in vitro flow loop model and ex vivo swine AV shunt model. MethodsThe thrombogenicity of FP-EES, BioLinx polymer zotarolimus-eluting stent (BL-ZES), and biodegradable polymer everolimus-eluting stent (BP-EES) was assessed acutely using the swine AV shunt model under aspirin or clopidogrel SAPT. Stents were immunostained using antibodies against platelets and inflammatory markers and evaluated by confocal microscopy. Also, the adhesion of platelet and albumin on the three DESs was assessed by an in-vitro flow loop model using human platelets under aspirin SAPT and fluorescent albumin, respectively. ResultsIn the shunt model, FP-EES showed significantly less platelet and inflammatory cell adhesion than BL-ZES and BP-EES. In the flow loop model, FP-EES showed significantly less platelet coverage and more albumin adsorption than BL-ZES and BP-EES. ConclusionsThese results suggest FP-EES may have particular advantage for short-term DAPT compared to other DESs.

Pathological findings after third- and second-generation everolimus-eluting stent implantations in coronary arteries from autopsy cases and an atherosclerotic porcine model

Pathological changes after third-generation drug-eluting stent implantation remain unclear. We compared the tissue responses of coronary arteries after the implantation of third-generation abluminal biodegradable-polymer everolimus-eluting stent (3rd EES) and second-generation durable-polymer EES (2nd EES) using autopsy specimens and an atherosclerotic porcine model. We compared the histology of stented coronary arteries obtained by autopsy performed 1–10 months after 3rd EES (n (number of cases) = 4, stent-implanted period of 3–7 months) and 2nd EES (n (number of cases) = 9, stent-implanted period of 1–10 months) implantations. The ratio of covered stent struts was higher with 3rd EESs than with 2nd EESs (3rd; 0.824 ± 0.032 vs. 2nd; 0.736 ± 0.022, p = 0.035). Low-density lipoprotein receptor knockout minipigs were stented with 3rd or 2nd EES in the coronary arteries and the stented regions were investigated. The fibrin deposition around the 2nd EES was more prominent. Additionally, higher density of smooth muscle cells was confirmed after the 3rd EES implantation. Pathological examination after the 3rd EES demonstrated a combination of less fibrin deposition and more rapid acquisition of well-developed neointima as compared to the 2nd EES at autopsy and the atherosclerotic porcine model.

Comparison of neointimal coverage between biodegradable-polymer everolimus-eluting stent and durable-polymer everolimus-eluting stent using angioscopy for the patients with acute coronary syndrome

Abstract Background New-generation biodegradable-polymer platinum chromium everolimus-eluting stent (BP-PtCr-EES) is available, which has different polymer and alloy compare to more established stent design, a durable-polymer cobalt-chromium everolimus-eluting stent (DP-CoCr-EES). Purpose To compare neointimal coverage (NIC) between BP-PtCr-EES and DP-CoCr-EES by using coronary angioscopy (CAS). Methods A total of 36 patients (44 stents) with BP-PtCr-EES or DP-CoCr-EES who underwent CAS at 1 year after stenting were investigated. We compared angioscopic findings assessed by angioscopy between BP-PtCr-EES (n=18) and DP-CoCr-EES (n=26). NIC grade and yellow plaque grade (YPG) was adopted from earlier reports from grade 0 to 3. We determined maximum (max-) and minimum (min-) NIC grade and heterogeneity score (HGS = max NIC grade minus min NIC grade). We also assessed YPG and the presence of thrombus (TH). Results Six lesions (33.3%) in BP-PtCr-EES group and 7 (26.9%) lesions in DP-CoCr-EES group were culprit lesions of acute coronary syndrome, which did not statistically differ between the two groups (p=0.74). And there were no significant differences in stent diameter (BP-PtCr-EES: 2.97±0.39 mm vs DP-CoCr-EES: 3.14±0.45 mm, p=0.22) and length (BP-PtCr-EES: 26.9±7.9 mm vs DP-CoCr-EES: 28.4±8.0 mm, p=0.54). In terms of CAS findings, BP-PtCr-EES group has better neointimal coverage than DP-CoCr-EES group (max NIC grade: 2.6±0.7 vs 2.0±0.9, p=0.01. min NIC grade: 1.1±0.8 vs 0.5±0.5, p<0.01), but HGS was almost same (1.6±0.7 vs 1.5±0.9, p=0.70). YPG of BP-PtCr-EES group showed significantly lower than DP-CoCr-EES group (1.0±1.0 vs 1.7±1.0, p=0.02). The rate of TH was significantly lower in BP-PtCr-EES group than DP-CoCr-EES group (25%, n=6, vs 75%, n=18, p=0.03). There were no clinical events such as stent thrombosis or restenosis during the observation period in both stent groups. Conclusion Superior neointimal coverage and less YPG or TH were observed by CAS in the BP-PtCr-EES group at 1 year after stenting. Clinical significance was still unknown because of no clinical events in both groups. Prospective and large populations studies may be required. Funding Acknowledgement Type of funding source: None

Titanium-Nitride-Oxide–Coated Versus Everolimus-Eluting Stents in Acute Coronary Syndrome: The Randomized TIDES-ACS Trial

ObjectivesThis study sought to compare next-generation cobalt-chromium–based titanium-nitride-oxide (TiNO)–coated stents with a platinum-chromium–based biodegradable polymer everolimus-eluting stent (EES) in patients with acute coronary syndrome (ACS). BackgroundPrevious generation TiNO-coated stents showed acceptable performance in patients with ACS. MethodsIn a multicenter, randomized trial, we randomly assigned 1,491 ACS patients (2:1) to receive either a TiNO-coated stent (n = 989) or EES (n = 502). The primary endpoint was the rate of a composite of cardiac death, myocardial infarction (MI), or ischemia-driven target lesion revascularization at 12-month follow-up. The co-primary endpoint was a composite of cardiac death, MI, or major bleeding at 18 months. ResultsA primary endpoint event occurred in 6.3% of patients in the TiNO-coated stent group versus in 7.0% in the EES group (hazard ratio: 0.93; 95% confidence interval: 0.71 to 1.22; p = 0.66 for superiority; p < 0.001 for noninferiority). A co-primary endpoint event occurred in 3.7% of the patients in the TiNO group and in 7.8% in the EES group (hazard ratio: 0.64; 95% confidence interval: 0.51 to 0.80; p = 0.001). TiNO-coated stents were associated with lower rates of cardiac death (0.6% vs. 2.6%; p = 0.002) and MI (2.2% vs. 5.0%; p = 0.007) at 18 months of follow-up. Rates of target lesion revascularization were not significantly different at 18 months (5.8% vs. 4.4%; p = 0.27). ConclusionsIn patients with ACS, cobalt-chromium–based TiNO-coated stents were noninferior to platinum-chromium–based biodegradable polymer EES for major cardiac events at 12 months, and were superior for the co-primary endpoint of cardiac death, MI, and bleeding at 18 months. (Comparison of Titanium-Nitride-Oxide-Coated Bio-Active-Stent (Optimax™) to the Drug (Everolimus) -Eluting Stent (Synergy™) in Acute Coronary Syndrome [TIDES-ACS]; NCT02049229)

P269 Mid-term clinical outcomes of biodegradable polymer everolimus-eluting stents compared with durable polymer everolimus-eluting stents: a propensity-matched study

Abstract Background Introduction: Several studies have reported that durable polymer drug-eluting stents could cause delayed healing and late catch-up. Although biodegradable polymer everolimus-eluting stents (BP-EES) might solve these problems, there is few data about mid-term clinical outcomes of BP-EES compared with durable polymer everolimus-eluting stents (DP-EES). Purpose This study aimed to compare mid-term clinical outcomes between BP-EES and DP-EES. Methods Between January to December 2016, 206 consecutive patients were treated with BP-EES and 177 consecutive patients were treated with DP-EES in our Heart Center. The primary endpoint was 3-year cumulative incidence of target lesion failure (TLF) defined as cardiac death, target vessel-related myocardial infarction and clinical-driven target lesion revascularization. Moreover, clinical-driven target vessel revascularization (TVR) and definite stent thrombosis (ST) were also evaluated. Results After propensity score matching, 160 patients were selected in each group. At 3 years, the cumulative incidences of TLF were 4.1% in BP-EES group vs. 7.9% in DP-EES (p = 0.12). Similarly, those of clinical-driven TVR were not different between the 2 groups (10.9% vs. 8.0%, p = 0.39). The incidence of definite ST in BP-EES tended to be higher than in that of DP-EES (BP-EES vs. DP-EES; 0% vs. 1.8%, p = 0.06). Conclusions There were no significant differences of TLF between BP-EES and DP-EES within 3 years. In this study, BP-EES seems to prevent definite ST and be safer than DP-EES in mid-term. Abstract P269 Figure.

P2796Biodegradable polymer everolimus-eluting stents versus durable polymer everolimus-eluting stents in diabetic patients: a 3-year propensity-matched study

Abstract Background and introduction Diabetic patients are at high risk of adverse cardiovascular events after percutaneous coronary intervention (PCI) even with durable polymer drug-eluting stents. A biodegradable polymer everolimus-eluting stents (BP-EES) might improve clinical outcomes in patients with diabetes mellitus. Purpose This study aimed to compare the mid-term clinical outcomes between BP-EES and durable polymer everolimus-eluting stents (DP-EES) in diabetic patients. Methods We investigated consecutive 383 patients treated with BP-EES or DP-EES at our Heart Center between January and December 2016. Among these patients, 155 (40.5%) patients had diabetes mellitus. The primary endpoint was 3-year cumulative incidence of target lesion failure (TLF) defined as target vessel-related myocardial infarction (MI) and clinical-driven target lesion revascularization (TLR). Moreover, the incidence of definite stent thrombosis (ST) was also evaluated. Results After propensity score matching, 148 patients were divided into 2 groups (BP-EES; N=74, DP-EES; N=74). The 3-year cumulative incidences of TLF were significantly lower in BP-EES group than in DP-EES group (BP-EES vs. DP-EES; 1.4% vs. 11.4%, p=0.01). The incidence of cardiac death, target vessel-related MI, and definite ST were none in the both group. Figure 1 Conclusions In diabetic patients, the incidence of TLR within 3 years was significantly lower in BP-EES than in DP-EES. In PCI for diabetic patients, BP-EES might improve clinical outcomes compared to DP-EES.

P3385Difference of vascular healing after percutaneous coronary intervention between 4 kinds of new generation drug-eluting stents: an optical coherence tomography analysis

Abstract Background New generation drug eluting stents (DES) have improved target vessel failure as compared with early generation DES and bare metal stent. Contemporary several new generation DES are different each other regarding strut thickness and drug and polymer type. A little is known about which stent induces a more favorable vascular healing at follow up. Purpose In this study, we compared the vascular healing at 8-month follow up by optical coherence tomography (OCT) between 4 different kinds of new generation DES. Methods We enrolled 112 consecutive patients (121 lesions) who underwent PCI using 4 kinds of new generation DES including biodegradable-polymer everolimus-eluting stents (BP-EES), biodegradable-polymer sirolimus-eluting stents (BP-SES), durable-polymer everolimus-eluting stents (DP-EES) and durable-polymer zotarolimus-eluting stents (DP-ZES) and who underwent 8-month follow up angiogram and OCT between July 2016 and April 2018. We compared the OCT parameters including percentage of covered struts, uncovered struts, well-apposed and uncovered struts, malapposed strut and mean neointimal hyperplasia (NIH) thickness between them. Results BP-EES consisted of 29 lesions, BP-SES consisted of 25 lesions, DP-EES consisted of 38 lesions and DP-ZES consisted of 29 lesions. A total of 734 frames with 5163 struts in BP-EES, 481 frames with 4214 struts in BP-SES, 783 frames with 6119 struts in DP-EES and 583 frames with 4708 struts in DP-ZES were analyzed. As shown in a table, mean NIH thickness was significantly higher in BP-EES and BP-SES. Thus, we compared the OCT parameters between durable-polymer (DP) group including DP-ZES and DP-EES and biodegradable-polymer (BP) group including BP-EES and BP-SES. The percentage of uncovered struts was significantly lower and mean NIH thickness was significantly higher in BP group than DP group. Results of OCT parameters BP-EES (n=29) BP-SES (n=25) DP-EES (n=38) DP-ZES (n=29) P value BP group (n=54) DP group (n=67) P value Covered struts (%) 89.5±13.6 92.4±8.6 85.5±17.5 85.0±17.7 0.29 90.9±11.6 85.3±17.4 0.08 Uncovered struts (%) 8.8±10.8 7.1±8.7 14.5±17.5 15.0±17.7 0.14 8.0±9.9 14.7±17.4 0.03 Well-apposed and uncovered struts (%) 7.9±9.9 5.9±7.7 11.7±13.1 12.3±14.0 0.15 7.0±8.9 11.9±13.4 0.04 Malapposed struts (%) 0.8±1.6 1.3±2.2 2.7±5.8 2.7±4.7 0.33 1.0±1.9 2.7±5.3 0.07 Mean NIH thickness (μm) 102±57 121±48 78±28 88±33 &lt;0.01 111±53 82±31 &lt;0.01 Conclusion The present OCT study demonstrated that delayed neointimal healing characterized by the presence of uncovered struts and lower mean NIH thickness was less common in BP group than DP gruop. Biodegradable-polymer may be more favorable than durable-polymer from the point of view of vascular healing.

TCT-638 Diabetes Mellitus Confers Worse Clinical Outcomes at 1 Year Compared to Non–Diabetes Mellitus in an All-Comer Population Implanted With Biodegradable Polymer Everolimus-Eluting Stents

TCT-638 Diabetes Mellitus Confers Worse Clinical Outcomes at 1 Year Compared to Non–Diabetes Mellitus in an All-Comer Population Implanted With Biodegradable Polymer Everolimus-Eluting Stents

Everolimus-Eluting Biodegradable Polymer Versus Everolimus-Eluting Durable Polymer Stent for Coronary Revascularization in Routine Clinical Practice

ObjectivesThe aim of this study was to compare the efficacy and safety of a thin-strut, biodegradable-polymer everolimus-eluting stent (BP-EES) (Synergy, Boston Scientific, Marlborough, Massachusetts) and a thin-strut, durable-polymer everolimus-eluting stent (DP-EES) (XIENCE, Abbott Vascular, Abbott Park, Illinois) in an all-comers population. BackgroundBP-EES have been shown to be noninferior to DP-EES in randomized trials in patients at low to moderate risk. MethodsAmong 7,042 consecutive patients who underwent percutaneous coronary intervention between December 2012 and December 2016, 3,870 patients were exclusively treated with BP-EES (n = 1,343) or with DP-EES (n = 2,527). After propensity score matching, the final study population consisted of 1,041 matched patients. The primary endpoint was the device-oriented composite endpoint (cardiac death, target vessel myocardial infarction, and target lesion revascularization) at 12 months. ResultsThe device-oriented composite endpoint did not differ between the 2 groups (7.8% with BP-EES vs. 7.1% with DP-EES; hazard ratio: 1.12; 95% confidence interval: 0.81 to 1.53; p = 0.49). There were no differences in rates of cardiac death (3.0% vs. 3.0%; p = 1.00), target vessel myocardial infarction (3.6% vs. 3.1%; p = 0.53), and target lesion revascularization (3.0% vs. 2.5%; p = 0.41). The rate of acute stent thrombosis was significantly higher in the BP-EES group compared with the DP-EES group (1.2% vs. 0.3%; hazard ratio: 4.00; 95% confidence interval: 1.13 to 14.19; p = 0.032). At 12 months, the frequency of definite stent thrombosis did not differ (1.5% vs. 0.9%; hazard ratio: 1.67; 95% confidence interval: 0.73 to 3.82; p = 0.22). ConclusionsIn this consecutively enrolled percutaneous coronary intervention population reflecting routine clinical practice, no difference in the device-oriented composite endpoint between BP-EES and DP-EES was observed throughout 12 months. There was a higher rate of acute stent thrombosis with the BP-EES, a difference that disappeared at 1 year. (CARDIOBASE Bern PCI Registry; NCT02241291)

Comparison of the biodegradable polymer everolimus-eluting stent with contemporary drug-eluting stents: A systematic review and meta-analysis

AimsDespite similar efficacy and safety profile in pilot studies, bioresorbable polymer drug-eluting stents (BP-DES) could have potential benefit over latest generation durable polymer (DP)-DES by facilitating vessel healing, therefore reducing inflammation and neoatherosclerosis leading to enhanced clinical safety. Therefore, we sought to perform a meta-analysis of randomized clinical trials (RCTs) comparing the safety and efficacy of everolimus-eluting BP-DES (BP-EES) to second-generation DP-DES. Methods and resultsWe conducted a systematic review and meta-analysis to examine the safety and efficacy of BP-EES in patients treated for coronary artery disease. We searched PubMed, Scopus, and the Cochrane Library through February 2018 for RCTs that included outcome data on BP-EES. We identified four eligible studies, which included a total of 4631 patients. Three studies reported a follow-up of one year and one study of five years. The BP-EES group, included 2315 patients and the DP-DES group included 2316 patients (1143 treated with DP-EES and 1173 treated with zotarolimus eluting DP-DES). Patient's characteristics were comparable between the two groups except for higher prevalence of prior MI in the DP-DES group (25.7 vs 22.5%, respectively, p = 0.001). Procedural characteristics were comparable among groups except for slightly longer lesions in the BP-EES group compared to the DP-DES group (mean 15.1 vs 14.9 mm, p = 0.04). No significant differences were observed for cardiac mortality (p = 0.72), occurrence of MI (p = 0.64), any TLR (p = 0.93), ST (p = 0.85) or major adverse cardiac events (p = 0.43). ConclusionOverall, based on the available data BP-EES had similar one-year outcomes to contemporary DP-DES. Whether these devices could enhance clinical safety remains to be evaluated at longer follow-up.

Very thin strut biodegradable polymer everolimus-eluting and sirolimus-eluting stents versus durable polymer zotarolimus-eluting stents in allcomers with coronary artery disease (BIO-RESORT): a three-arm, randomised, non-inferiority trial

In patients with coronary artery disease, treated with durable polymer-coated drug-eluting stents, the life-long presence of the polymer might delay arterial healing. Novel very thin strut biodegradable polymer stents, which leave only a bare metal stent after polymer resorption, might improve long-term outcome. We investigated in allcomers the safety and efficacy of three stents eluting either everolimus, sirolimus, or zotarolimus, often clinically used but never compared, of which the biodegradable polymer everolimus-eluting stent was never before assessed in allcomers. The large-scale, investigator-initiated, multicentre, assessor and patient blinded, three-arm, randomised, BIO-RESORT non-inferiority trial was done at four clinical sites in the Netherlands. All-comer patients were aged 18 years or older, capable of providing informed consent, and required a percutaneous coronary intervention with drug-eluting stent implantation according to clinical guidelines or the operators' judgment. Exclusion criteria were: participation in another randomised drug or device study before reaching the primary endpoint of that study; planned surgery necessitating interruption of dual antiplatelet therapy within the first 6 months; known intolerance to components of the investigational product or medication required; uncertainty about the adherence to follow-up procedures or an assumed life expectancy of less than 1 year; or known pregnancy. Web-based computer-generated allocation sequences randomly assigned patients (1:1:1) to treatment with very thin strut biodegradable polymer everolimus-eluting or sirolimus-eluting stents (which differ substantially in type, amount, distribution, and resorption speed of their respective coating), or thin strut durable polymer zotarolimus-eluting stents. The primary endpoint was a composite of safety (cardiac death or target vessel-related myocardial infarction) and efficacy (target vessel revascularisation) at 12 months of follow up with a very thin strut biodegradable polymer of either everolimus-eluting or sirolimus-eluting stents, compared with durable polymer zotarolimus-eluting stents, analysed by intention to treat (non-inferiority margin 3·5%). This trial was registered with ClinicalTrials.gov, number NCT01674803. From Dec 21, 2012, to Aug 24, 2015, 3514 patients were enrolled and analysed, of whom 2449 (70%) had acute coronary syndromes, which included 1073 (31%) ST-elevation myocardial infarctions. 12 month follow-up of 3490 (99%) patients (three lost to follow-up; 21 withdrawals) was available. The primary endpoint was met by 55 (5%) of 1172 patients assigned to everolimus-eluting stents, 55 (5%) of 1169 assigned to sirolimus-eluting stents and 63 (5%) of 1173 assigned to zotarolimus-eluting stents. Non-inferiority of the everolimus-eluting stents and sirolimus-eluting stents compared with zotarolimus-eluting stents was confirmed (both -0·7% absolute risk difference, 95% CI -2·4 to 1·1; upper limit of one sided 95% CI 0·8%, pnon-inferiority<0·0001). Definite stent thrombosis (defined by the Academic Research Consortium) occurred in four (0·3%) of 1172 patients who were allocated to everolimus-eluting stents, four (0·3%) of 1169 patients who were allocated to sirolimus-eluting stents, and three (0·3%) of 1173 patients who were allocated to zotarolimus-eluting stents (log-rank p=0·70 for both comparisons with zotarolimus-eluting stents). At 12 month follow-up, both very thin strut drug-eluting stents with dissimilar biodegradable polymer coatings (eluting either everolimus or sirolimus) were non-inferior to the durable polymer stent (eluting zotarolimus) in treating allcomers with a high proportion of patients with acute coronary syndromes. The absence of a loss of 1 year safety and efficacy with the use of these two biodegradable polymer-coated stents is a prerequisite before assessing their potential longer-term benefits. Biotronik, Boston Scientific, and Medtronic.

TCT-462 Efficacy and Safety of Biodegradable Polymer Everolimus-eluting stents versus Durable Polymer Biolimus-eluting stents: A direct comparison meta-analysis of 8,476 patients from randomized trials

There is a paucity of data on long-term efficacy and safety of biodegradable polymer biolimus-eluting stent (BES) compared with durable polymer everolimus-eluting stent (EES) in patients undergoing percutaneous coronary intervention. Randomized controlled trials comparing EES with BES were