Benefit Of Drug-eluting Stents Research Articles

Abstract 11557: Rates of Early Target Vessel Revascularization and Target Lesion Revascularization Amongst Third Generation Drug-Eluting Stents

Background: While the benefits of drug-eluting stents (DES) during percutaneous coronary intervention (PCI) are well established, the frequency and timing of repeat revascularization events, particularly early events, is not well described in contemporary clinical practice. Methods: Patients undergoing PCI at two large tertiary centers in a single health system from April 2014 to December 2019 were prospectively enrolled into the NCDR CathPCI Registry. Target vessel revascularization (TVR) and target lesion revascularization (TLR) were defined as a repeat intervention to the index vessel or lesion respectively and determined by linking to subsequent PCI events and CABG admissions in the EMR. Early TVR and TLR rates were identified at 30 days, 90 days, six months, and one year. Logistic regression was used to estimate the association between stent type and TVR/TLR at the pre-specified time points. Generalized estimating equations with nested modeling were used to account for patients with multiple vessels and lesions. Results: Overall, 8,221 PCI procedures were identified in 7,128 patients with 9,558 vessel interventions and 12,019 lesion interventions. There were similar rates of TVR for Zotarolimus eluting durable polymer stents (ZES-DP), Everolimus eluting bioabsorbable polymer stents (EES-BAP), and Everolimus eluting durable polymer stents (EES-DP) at 30 days (p=0.61), 90 days (p=0.79), six months (p=0.58), and one year (p= 0.35). There were similarly no differences in TLR between stent types at each time point (p= 0.57, 0.79, 0.16, 0.13 respectively). The total rates of TLR and TVR progressed linearly throughout the year following PCI with nearly half of all repeat revascularization events occurring within 6 months. Table 1. Conclusions: Within a single health system from 2014 to 2019, ZES-DP, EES-BAP, and EES-DP were associated with similar rates of TVR and TLR. These events appear to occur earlier than typically reported in clinical trials.

The Biolimus A9-coated BioFreedom™ stent: from clinical efficacy to real-world evidence.

In this state-of-the-art review, we present the findings and a critical analysis of the Leaders Free trial program, evaluating outcomes of a new stent-generation based on polymer-free technology, in this case the BioFreedom™ (Biosensors Europe, Switzerland), in patients at high bleeding risk (HBR). Polymer-free drug-coated stents were designed to obtain a device with the antirestenotic benefits of drug-eluting stents but without the polymer coating as potential trigger for delayed arterial wall healing and subsequent late ischemic adverse events, causing a prolonged dependence on dual antiplatelet therapy after stenting. This offers therefore the potential of a promising device-based strategy in a complex growing population of patients with combined HBR and high thrombosis risk, due to the possible reduction of antithrombotic duration.

Second-generation drug-eluting stents versus drug-coated balloons for the treatment of coronary in-stent restenosis: A systematic review and meta-analysis.

The benefit of drug-eluting stents (DES) versus drug-coated balloons (DCB) in coronary artery in-stent restenosis (ISR) for the prevention of target lesion revascularization (TLR), stent thrombosis, and mortality remains uncertain. Our aim was to synthesize the available evidence from randomized clinical trials (RCTs) and observational studies that directly compare second-generation drug-eluting stents (SG-DES) and DCB for the treatment of coronary ISR. Medline, Embase, and Cochrane Central were searched for RCTs or observational studies, published up to March 15, 2017. A random effects model meta-analysis investigating clinical and angiographic outcomes was conducted for RCTs and observational studies that compared SG-DES versus DCB for the treatment of ISR. Ten studies and 2,173 patients were included in this meta-analysis. The two treatment strategies were proven equal with regards to TLR, myocardial infarction, stent thrombosis, and cardiac mortality in both randomized and observational studies. No difference was found among RCTs for all-cause mortality, while in observational studies, patients who were treated with SG-DES had a lower mortality compared to DCB (OR: 0.47; 95% CI: 0.27-0.83). In the pooled analysis also (RCTs and observational studies), SG-DES were associated with lower all-cause mortality compared to DCB. Patients treated with SG-DES were also superior in terms of minimal lumen diameter (standardized mean difference: 0.39; 95% CI: 0.12-0.66). The two treatment strategies are equal for the treatment of ISR, while the difference in all-cause mortality might be potentially explained by baseline differences in the two groups among real-world studies.

Impact of Mild-to-Moderate Chronic Kidney Disease on One Year Outcomes after Percutaneous Coronary Intervention

Background/Aim: Patients with severe chronic kidney disease (CKD) have a higher risk of adverse events after percutaneous coronary intervention (PCI). There is conflicting evidence regarding the benefit of drug-eluting stents (DES) in patients with CKD. This study is aimed at assessing the effect of mild-to-moderate CKD on PCI outcomes, and determining if DES reduce adverse events amongst these patients. Method: We used our PCI database to determine demographic, procedural and outcome variables for 1960 consecutive patients (October 2009-October 2012). Kidney function was measured by the estimated glomerular filtration rate (eGFR - CKD-Epidemiology Collaboration creatinine based). Multivariate analysis was performed to determine independent variables associated with mortality and major adverse cardiovascular events (MACE). Results: The independent variables, predictive of 12-month mortality in PCI patients, were: age >64 years (hazard ratio [HR] 3.10 [95% CI 1.73-5.55], p < 0.001), 3-vessel disease (HR 1.72 [95% CI 1.10-2.68], p = 0.016) and CKD stage. Compared to stage 1 CKD (eGFR >89), HR of death increased in a progressive pattern below eGFR <75: eGFR 60-74, HR 2.40 (95% CI 1.2-4.78), p = 0.013, eGFR 45-59, HR 3.27 (95% CI 1.55-6.9), p = 0.002, eGFR 30-44, HR 4.10 (95% CI 1.82-9.24), p = 0.001, eGFR <30, HR 7.97 (95% CI 3.65-17.40), p < 0.001. In patients with eGFR <75, multivariate analysis demonstrated that DES use was an independent predictor of lower MACE (HR BMS vs. DES 1.8, p = 0.0044). Conclusion: Age, severity of CKD and 3-vessel disease were independent predictors of mortality following PCI. The mortality risk in CKD patients increased progressively with eGFR <75. The use of DES was associated with a lower rate of MACE in CKD patients with eGFR <75.

Safety and efficacy of drug eluting stents in patients with spontaneous coronary artery dissection

AimsGiven the different pathogenesis, use of drug eluting stent (DES) in patients with Spontaneous Coronary Artery Dissection SCAD may delay the healing of the dissected vessel. Aim of our study was to compare the safety and the efficacy of DES vs. bare metal stent (BMS) in a cohort of patients who underwent stenting for SCAD. Methods and resultsConsecutive patients with SCAD between January 1995 and August 2014 were retrospectively identified in 12 centers and included. Major Adverse Cardiac Events (MACE) was the primary end point. A total of 238 SCAD patients were identified: of them 108 patients underwent PCI with DES or BMS. Overall 24 patients (22.2%) suffered an intra-procedural complication without any differences between the 2 groups. At median follow-up of 1201days (Inter Quartile Range 541–2760), incidence of the primary endpoint showed a trend towards less events in the DES-treated patients (38.7% vs. 25.9% p=0.14) mainly driven by the benefit of DES in terms of TVR (17.6% vs. 4%, p=0.08), mortality (16.8% vs. 9.3%, p=0.4), and MI rate (16% vs. 8.4%, p=0.33). STEMI at presentation (HR 6.4, CI 95% 1.29–31.9, p=0.02) but not kind of stent (HR 0.97, CI 95% 0.2–4.7, p=0.9) emerged as independently related to prognosis at multivariable analysis. ConclusionsIn SCAD patients use of DES seems to be as safe as BMS with trend of better efficacy in the long term.

Impact of smoking on health-related quality of Life after percutaneous coronary intervention treated with drug-eluting stents: a longitudinal observational study

BackgroundSmoking has been shown to reduce health-related quality of life (HRQOL) in patients with coronary artery disease (CAD) undergoing percutanous coronary intervention (PCI) either by means of balloon angioplasty or with the use of bare-metal stents (BMS). Drug-eluting stents (DES) have now been widely used and are related to substantial reduction of restenosis and significantly improved HRQOL compared with BMS. This study aimed to evaluate the effects of smoking on HRQOL in patients after PCI in DES era.MethodsA cohort of 649 patients admitted for CAD and treated with drug-eluting stents were included in this prospective, observational study. Patients were classified as non-smokers (n = 351, 54.1%), quitters (n = 126, 19,4%), or persistent smokers (n = 172, 26.5%) according to their smoking status at the time they first admitted to hospital and during the first year of follow-up. Each patient was prospectively interviewed at baseline, 6 months and 1 year following PCI. HRQOL was assessed with the use of Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36).ResultsFor the overall population, HRQOL scores at 1-year follow-up were significantly higher than baseline for all 8 domains. At 1-year follow-up, the HRQOL scores in persistent smokers were still lower than that in non-smokers in 6 domains except for bodily pain and mental health, and than that in quitters in 5 domains except for bodily pain, role emotional and mental health. There were no significant differences with regard to the scores between non-smokers and quitters except role emotional for which non-smokers had higher scores. After adjustment, persistent smokers demonstrated significantly less improvements in HRQOL than non-smokers in 6 domains except for bodily pain and social functioning and significantly less improvement than quitters for general health. Improvements of quitters were comparable to that of non-smokers in all domains. Multivariate linear regression analyses showed persistent smoking was an independent risk factor for PCS and MCS improvements.ConclusionsPersistent smoking substantially diminishes the potential quality-of-life benefits of DES. Efforts should be made to promote smoking cessation after DES implantation which could greatly improve the health quality outcomes.

Drug-Eluting vs. Bare-Metal Stents: Is it a Matter of Vessel Size?

Background: Although drug-eluting stents (DES) for percutaneous coronary intervention have dramatically reduced the incidence of in-stent restenosis, their deployment for large-size coronary lesions is still controversial because of problems such as prolonged dual antiplatelet therapy, late in-stent thrombosis and costs. Aim: This study sought to evaluate the safety and effectiveness of drug-eluting stents (DES) compared to baremetal stents (BMS) for patients with large coronary vessels ≥ 3.5 mm. Methods: This is a retrospective case-control comparative study conducted in the cardiology A department of the university hospital Fattouma Bourguiba in Monastir. A total of 77 consecutive patients (80 lesions) who underwent, between October 2003 and March 2014, successfully DES implantation were compared to 73 consecutive patients (84 lesions) who were treated with BMS in large coronary vessels ≥ 3.5 mm. Results: The average age in our population was 59.7 ± 11.3 years with a male majority without any significant difference between the two groups. The DES group contained significantly more patients with diabetes (67.5% vs. 38.1%; p<0.0001) and a history of coronary heart disease (40% vs. 16.7%; p=0.001). The BMS group had significantly more procedures in the aftermath of MI (18.8% vs. 40.5%; p=0.002) including more primary angioplasty (6.7% against 47.1%; p=0.006). About two-thirds of the study patients had multi-vessel disease with equal distribution in both groups. The average duration of dual antiplatelet therapy was significantly prolonged in the DES group: 13.01 ± 8.31 months vs. 7.59 ± 8.19 months; p<0.0001. A mean follow of 27.87 ± 14.82 months was obtained. At 12 months, DES led to a significant reduction in the combined rate of major cardiac events by about 70% (OR=0.32; 95% CI: 0.119 to 0.858; p=0.019) without allowing a significant reduction in the rates of in-stent restenosis, in-stent thrombosis, target vessel revascularization or non-combined major cardiac events. During longterm follow-up, the benefit of DES in terms of MACE was maintained by allowing a 60% reduction in the combined rate of major cardiac events (OR=0.406; 95% CI: 0.172 to 0.955; p=0.035). Multivariate analysis identified the BMS as an independent predictor of major cardiac events and death. However, the type of stent does not appear as a factor influencing the ISR and target lesion revascularization rates. Conclusion: The results of our study demonstrate a clear clinical benefit of drug-eluting stents during angioplasty of large coronary arteries in reducing major cardiac events and death without having any effect on in-stent restenosis, in-stent thrombosis nor target lesion revascularization.

The benefits of drug-eluting stents in the treatment of coronary artery disease

© 2016 Kiramijyan and Liu. This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/ terms.php and incorporate the Creative Commons Attribution – Non Commercial (unported, v3.0) License (http://creativecommons.org/licenses/by-nc/3.0/). By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms (https://www.dovepress.com/terms.php). Research Reports in Clinical Cardiology 2016:7 9–25 submit your manuscript | www.dovepress.com Dovepress 9

0234: Drug-eluting stents versus bare-metal stent in large coronary arteries

Although drug-eluting stents (DES) have been shown to dramatically reduce restenosis and improve the rate of event-free survival, the benefit of DES appears to be limited to restenosis. In this retrospective, single-center study we aimed to compare the long-term outcomes of DES versus bare-metal stent (BMS) in large coronary arteries (diameter ≥3.5mm). A total of 164 consecutive patients (mean age 60 years) required percutaneous coronary intervention with stents ≥3.5mm in diameter, 84 were BMS and 80 DES. The primary endpoint was major adverse cardiac events (MACE) defined as angiographically defined in-stent restenosis (ISR), stent thrombosis and death from any cause. A mean clinical follow up of 28 months was obtained. The DES group had higher rates of diabetes (63% vs 37%, p=0.001), previous CAD (74% vs 25%, p=0.001) and previous PCI (69% vs 31%, p=<0.04). There was no significant difference between the two groups regarding the rate of hyper-tension, dyslipidemia, smokers and the mean left ventricular ejection fraction. There was a higher average stent length in the DES group (18.7 vs 16.3, p=0.011) as well as a lower average stent diameter (3.54 vs 3.63, p=0.003). There was a significant difference in MACE between the two groups in favour of DES (11.3% DES vs 23.8% BMS group, p=0.04) at 28 months. The rate of in-stent restenosis (ISR) was significantly reduced among patients receiving DES with ISR rates of 15.8% among patients receiving DES compared to 41.7% among those receiving BMS (p=0.025). There were no significant differences in the rate of death or stent thrombosis. In patients requiring stenting of large coronary arteries, there was reduced MACE in patients treated with DES. This benefit was primarily driven by decreased in-stent restenosis rate.

Abstract 11774: Beyond Restenosis - Patients’ Preferences for Drug Eluting versus Bare Metal Stents

Introduction: Drug eluting stents (DES) reduce the need for target vessel revascularization, and are used in ~80% of percutaneous coronary interventions (PCI) in the US. However, DES also necessitate the use of prolonged dual anti-platelet therapy (DAPT), which is associated with increased bleeding/bruises, can complicate future surgeries and can increase patients’ medication costs (DAPT drawbacks). Patients’ preferences regarding the benefits of DES and DAPT drawbacks have not previously been studied or reported. Methods: In a prospective, observational cohort study, consecutive patients undergoing PCI at 2 Kansas City hospitals completed a survey assessing the importance of the following factors related to the decision to receive DES: need for repeat PCI and DAPT drawbacks. Each factor was rated from 1 (not important) to 10 (extremely important). The most important factor, or group of factors, to each patient was then identified. Results: Among 317 PCI patients (66% male, 71% white, 45% DM, 80% HTN, 43% with prior PCI), 21% did not consider the need for repeat PCI as the most important factor (Figure). Only 14% considered the need for repeat PCI the single most important factor and 65% considered at least one DAPT drawback as important as repeat PCI. A third (32.8%) ranked minor bleeding/bruising as the most important factor (alone (5.5%) or with other domains (27.3%)). Conclusions: While the need for repeat PCI is an important factor to patients considering stent options, 85% of PCI patients regard other factors to be at least as important. Eliciting patients’ preferences is important to better tailor stent choices to the goals and values of individual patients undergoing PCI.

Abstract 20395: Racial/Ethnic and Gender Disparities in Use of Drug-Eluting vs. Bare Metal Stents in ST-Elevation Myocardial Infarction Patients, 2006-2012

Background: Recent evidence continues to show the benefit of drug-eluting stents (DES) over bare metal stents (BMS) in patient outcomes following ST-elevation myocardial infarction (STEMI), although the use of DES may be contraindicated in patients with specific comorbidities. In this study, we investigated racial/ethnic and gender disparities in the use of DES, after controlling for the effects of age, insurance status, secular trends, and comorbidities. Methods: The study population included all STEMI patients (n=60,218) who received PCI and at least one stent in any Florida acute-care hospital during 2006-2012. Hospital discharge data were analyzed. Procedure codes identified DES (ICD-9-CM 36.07) and BMS (ICD-9-CM 36.06). We used logistic regression to model the odds of receiving a DES. Potential predictors included in the model were patient age, racial/ethnic-gender group (referent=White men), year, payer (referent=commercial), diabetes, atrial fibrillation (AFIB), chronic kidney disease (CKD), and end-stage renal disease (ESRD). Results: Among all STEMI patients, Hispanic women were most likely to receive a DES (61.2%) and Black men were least likely (46.8%). Furthermore, the % of patients who received no stent also varied from 6.7% among Hispanic men to 12.8% among Black women. Multivariable logistic regression results were highly significant, with included independent variables significantly predictive of the odds of receiving a DES in the expected directions. After adjustment and compared with White men, Hispanic women were 24% more likely to receive a DES (OR 1.24, 95%CI 1.13-1.37), White women were 8% more likely to receive a DES (p=0.001), and Black women were 15% less likely to receive a DES (OR 0.85, 95% CI 0.76-0.95). There were no significant differences in DES usage for Hispanic men or for men or women or “other” race/ethnicity. The strongest disparity was observed for Black men, who were 32% less likely to receive a DES than White men (OR 0.68, 95% CI 0.63-0.74, p&lt;0.0001). Conclusions: In this real-world analysis of unselected and recent STEMI patients, a significant disparity in use of DES for Black men and women was observed. This disparity was not explained by patient age, payer or comorbidities, nor by the secular trend.

TCT-661 Vascular Brachytherapy versus Drug-Eluting Stents in the Treatment of In-Stent Restenosis: a Meta-Analysis of Long Term Outcomes

Clinical trials have shown a short term benefit of drug eluting stents (DES) compared to vascular brachytherapy (VBT) for the treatment of in-stent restenosis (ISR). The long term benefits of DES vs. VBT are conflicting in the literature. This study aimed to do a meta-analysis of long term outcomes

Evolving management of patients treated by drug-eluting stent: Prevention of late events

Drug eluting stents (DES) were introduced in clinical practice to overcome the problem of in-stent restenosis (ISR) that limited the overall efficacy of percutaneous coronary revascularization with bare metal stent (BMS). Long-term outcome data confirm a sustained benefit of DES as compared with BMS. However, this benefit is mainly evident in the first year of follow-up. Indeed, DES-related events may extend over this time, due to late events (late ISR and/or very late stent thrombosis). Prevention of late failure of DES may become a specific therapeutic target.

Abstract 533: Micro RNA-based Strategy to Preserve Endothelial Function After Angioplasty

Coronary artery disease is currently a leading cause of death worldwide. Despite all the benefits of drug-eluting stents (DES), concerns have been raised over their long-term safety, with particular reference to stent thrombosis due to delayed endothelial cell (EC) coverage. Here we describe a method that exploits the endogenous miRNAs to specifically inhibit vascular smooth muscle cell (VSMC) proliferation, the major cause of restenosis, without affecting re-endothelialization. By inserting four target sequences of the EC specific mir-126 into the 3’UTR of p27 expressing adenoviruses (p27-126TS), we were able to specifically inhibit VSMC proliferation and migration while EC were able to proliferate, migrate and form capillary-like networks. Balloon injured rat carotid artery infected with p27-126TS viruses exhibited complete inhibition of restenosis with complete re-endothelialization after two weeks (Fig. A). Moreover, hypercoagulability assessed by measuring plasma levels of D-dimer in the serum of rats treated with the p27-126TS was similar to the non-injured control (Fig. B). Finally, the vasodilatative response to acetylcholine of balloon injured carotid arteries treated with p27-126TS adenovirus were comparable to those of the control-noninjured vessel (Fig. C). This discovery may ultimately lead to a safer therapy than the non-selective DES and may diminish the need for prolonged dual antiplatelet therapy following percutaneous coronary intervention.

Short- and long-term outcomes in octogenarians undergoing percutaneous coronary intervention with stenting

To investigate the incidence of cardiac events in octogenarians who underwent percutaneous coronary intervention (PCI) with stenting, as well as to evaluate the efficacy and safety of drug-eluting stents (DES) in this population. The study included 6,129 consecutive patients who underwent PCI with stenting from 2000 to 2005 in our centre, of whom 291 (4.7%) were octogenarians. After adjusting for confounders, age ≥80 years appeared a significant predictor of high mortality at 30 days (adjusted hazard ratio [aHR] 1.92, 95% CI 1.23-3.01), and four years (aHR 2.25, 95% CI 1.77-2.85). No differences were seen with respect to incident myocardial infarction (MI), but target lesion (63.2 vs. 32.6 per 1,000 person-years at one year and 27.9 vs. 16.6 per 1,000 person-years at four years) and vessel (83.1 vs. 52.9 per 1,000 person-years at one year and 37.7 vs. 25.0 per 1,000 person-years at four years) revascularisation rates were lower in octogenarians. When comparing DES with bare metal stents (BMS) in octogenarians, mortality and MI rates were comparable, but there was a significantly lower incidence of target lesion revascularisation at one- (9.5 vs. 0.6 per 1,000 person-years, aHR 0.07, 95% CI 0.01-0.57) and four-year (3.4 vs. 0.7 per 1,000 person-years, aHR 0.16, 95% CI 0.04-0.59) follow-up in patients who received a DES. Octogenarians undergoing PCI with stenting have an increased mortality risk, whereas the rates of repeat revascularisation in octogenarians are lower. This study suggests that the benefit of DES in reducing revascularisation rates is extended to elderly patients.

Drug-eluting stents versus bare-metal stents in primary percutaneous coronary intervention

While the benefits of drug-eluting stents (DES) in low-risk populations are well established, there is ongoing debate about their role in the higher risk setting of acute ST elevation myocardial infarction. This was in response to early studies, which investigated the first generation of DES, demonstrating increased occurrence of very late stent thrombosis. However, more potent antiplatelet agents, novel antithrombotic agents and evolution of DES design and polymers have reduced the occurrence of very late stent thrombosis. Studies evaluating shorter duration of dual antiplatelet therapy following the use of DES are currently underway. This review examines the relevant literature and analyzes the safety and efficacy of implanting DES in patients with ST elevation myocardial infarction.

TCT-574 Drug-eluting stent with biodegradable polymer in patients with STEMI – short and long term outcomes: data from e-NOBORI and NOBORI 2 trials

With the introduction of drug eluting stents (DES) in this decade, treatment of patients with STEMI with these devices has emerged as a rational PCI alternative. In spite of the unquestionable benefits of DES in terms of reduction of restenosis and TVR, specific concerns have arisen with regard to

Use of Drug-Eluting Stents as a Function of Predicted Benefit

Benefits of drug-eluting stents (DES) in percutaneous coronary intervention (PCI) are greatest in those at the highest risk of target-vessel revascularization (TVR). Drug-eluting stents cost more than bare-metal stents (BMS) and necessitate prolonged dual antiplatelet therapy (DAPT), which increases costs, bleeding risk, and risk of complications if DAPT is prematurely discontinued. Our objective was to assess whether DES are preferentially used in patients with higher predicted TVR risk and to estimate if lower use of DES in low-TVR-risk patients would be more cost-effective than the existing DES use pattern. We analyzed more than 1.5 million PCI procedures in the National Cardiovascular Data Registry (NCDR) CathPCI registry from 2004 through 2010 and estimated 1-year TVR risk with BMS using a validated model. We examined the association between TVR risk and DES use and the cost-effectiveness of lower DES use in low-TVR-risk patients (50% less DES use among patients with <10% TVR risk) compared with existing DES use. There was marked variation in physicians' use of DES (range 2%-100%). Use of DES was high across all predicted TVR risk categories (73.9% in TVR risk <10%; 78.0% in TVR risk 10%-20%; and 83.2% in TVR risk >20%), with a modest relationship between TVR risk and DES use (relative risk, 1.005 per 1% increase in TVR risk [95% CI, 1.005-1.006]). Reducing DES use by 50% in low-TVR-risk patients was projected to lower US health care costs by $205 million per year while increasing the overall TVR event rate by 0.5% (95% CI, 0.49%-0.51%) in absolute terms. Use of DES in the United States varies widely among physicians, with only a modest correlation to patients' risk of restenosis. Less DES use among patients with low risk of restenosis has the potential for significant cost savings for the US health care system while minimally increasing restenosis events.

Stent Selection in Patients with Myocardial Infarction: Drug Eluting, Biodegradable Polymers or Bare Metal Stents?

Percutaneous coronary intervention (PCI) has been increasingly used in the last years during interventional procedures in patients with acute coronary syndromes (ACS) including ST elevation myocardial infarction (STEMI) and non-ST elevation myocardial infarction (NSTEMI). In patients with either STEMI, NSTEMI, high risk ACS with EKG changes or cardiac enzymes rises; PCI with bare metal stent (BMS) implantation has been associated with a significant improvement in clinical outcome. Therefore, BMS implantation during primary PCI in STEMI has become a standard of practice. With the introduction of drug eluting stents (DESs) in this decade, the use of these new devices instead of BMSs in patients with STEMI has emerged as a rational PCI alternative in this particular subgroup of patients. In spite of the unquestionable benefits of DESs in terms of reduction of restenosis and TVR, specific concerns have arisen with regard to their long-term safety. High incidence of very late stent thrombosis has been described with these devices, and special attention should be paid in patients with unstable coronary lesions, in which plaque composition and remodeling may play a main role in their safety and long-term outcome. Intraluminal thrombus caused by plaque rupture is the most frequent mechanism of STEMI, in which the necrotic core and thin fibrous cap play a major role. In this context, the use of first DESs designs may be futile or even unsafe because delayed healing may further contribute to plaque instability. Adjunctive invasive imaging tools can improve stent deployment and safety outcome in these lesions with intravascular findings of plaque instability. Recently, other players such as new dedicated antithrombotic BMS designs, including selfexpanding stents or drug-eluting coated balloons, are exploring their potential indications in patients with ACS and myocardial infarction. This paper reports and discusses new stent devices and adjunctive pharmacologic agents. It also mentions and describes the recent patents of devices invented to use in these complex lesions subsets.

Abstract P271: Mortality Benefit With Drug-Eluting Stents in Observational Studies: Fact or Artifact? Insights From the Prospective, Multicenter EVENT (Evaluation of Drug Eluting Stents and Ischemic Events) Registry

Background: Both randomized trials and observational studies comparing drug-eluting stents (DES) with bare metal stents (BMS) have demonstrated substantial reductions in target lesion revascularization (TLR) with DES use. Data on mortality, however, are strikingly disparate with only observational studies supporting a benefit of DES. We hypothesized that these differences are related predominantly to residual selection biases in non-randomized studies. Methods: We examined the association between stent type (DES vs. BMS) and both TLR and mortality over one year among 9266 unselected pts who underwent PCI at 55 US centers and were enrolled in the prospective EVENT registry from 2004 to 2007. In addition to standard approaches to risk-adjustment (i.e., multivariable regression and propensity matching), we performed an instrumental variable (IV) analysis using the treatment era (2007 vs. 2004-6) as the instrument. Results: Overall 88% pts received DES, and there was a substantial difference by treatment year (93% in 2004-06, 73% in 2007, p&lt;0.001). Unadjusted event rates over one year were significantly lower with DES compared to BMS (Death: 2.5% vs. 5.6%, TLR: 4.2% vs. 6.9%, p for both &lt;0.001). Both multivariable and propensity-matched Cox regression analyses demonstrated a significantly lower risk of death and TLR with DES use (Table). IV analysis showed a strong trend towards lower TLR with DES but no difference in mortality. Conclusion: Among unselected PCI patients in contemporary practice, DES use is associated with a consistent reduction in TLR regardless of risk-adjustment methodology but no effect on mortality using IV analysis. These findings underscore the limitations of conventional multivariable and propensity score analyses to adequately address both known and unknown factors influencing treatment selection in non-randomized studies. Adjusted * risk of post discharge clinical outcomes over one year after PCI with drug-eluting stents (reference: bare metal stents) Death Any TLR Hazard ratio (95% CI) P value Hazard ratio (95% CI) P value Multivariable Cox regression 0.51 (0.37-0.69) &lt;0.001 0.49 (0.37-0.64) &lt;0.001 Propensity-matched Cox regression 0.54 (0.39-0.74) &lt;0.001 0.52 (0.39-0.69) &lt;0.001 Absolute risk difference(%) (95% CI) P value Absolute risk difference (%) (95% CI) P value Instrumental variable analysis (instrument: treatment era) 1.9 (-1.9, 5.7) 0.33 -4.5 (-9.0, 0.3) 0.07 TLR: Target Lesion revascularization; * Adjusted/ matched for: Age, gender, insurance status, hyperlipidemia, hypertension, diabetes, smoking status, medical history (myocardial infarction, peripheral artery disease, stroke, heart failure), history of PCI or bypass surgery, e Glomerular filtration rate, ejection fraction, multivessel disease, attempted lesion location (left main, LAD, SVG), # lesions treated, stent length, # of stents, maximum stent diameter