A prospective randomized comparison between paclitaxel and sirolimus stents in the real world of interventional cardiology

The evolution of coronary stents

INTRODUCTION

Percutaneous coronary intervention (PCI) is 40 years old this year. From its humble beginnings of experimental work, PCI has transitioned over years with coronary artery stenting now a standard medical procedure performed throughout the world. Areas covered: The conversion from plain old balloon angioplasty (POBA) to the present era of drug eluting stents (DES) has been driven by many technological advances and large bodies of clinical trial evidence. The journey to present day practice has seen many setbacks, such as acute vessel closure with POBA; rates of instant restenosis with bare metal stents (BMS) and more recently, high rates of stent thrombosis with bioabsorbable platforms. This work discusses POBA, why there was a need for BMS, the use of inhibiting drugs to create 1^st generation DES, the change of components to 2^nd generation DES, the use of absorbable drug reservoirs and platforms, and possible future directions with Prohealing Endothelial Progenitor Cell Capture Stents. Expert commentary: This paper reviews the evolution from the original pioneering work to modern day practice, highlighting landmark trials that changed practice. Modern day contemporary practice is now very safe based on the latest drug eluting stents and supported by large datasets.

Is There Any Significant Difference in Stent Thrombosis Between Sirolimus and Paclitaxel Eluting Stents?: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Several meta-analyses have shown no significant difference in stent thrombosis (ST) between sirolimus eluting stents (SES) and paclitaxel eluting stents (PES). However, other meta-analyses have found SES to be superior to PES. Therefore, to solve this issue, we aim to compare the clinical outcomes between SES and PES during a follow-up period of about 1 or more years.We have searched Medline and EMBASE for randomized controlled trials (RCTs) comparing SES with PES. These RCTs have been carefully analyzed and then different types of ST including ST defined by the Academic Research Consortium (ARC), acute ST, late and very late ST have all been considered as the clinical endpoints in this study. A follow-up period of about 1 year, between 1 and 2 years as well as a longer follow-up period between 1 and 5 years have been considered. Data were retrieved and combined by means of a fixed-effect model because of a lower heterogeneity observed among the results. Odd ratios (OR) and 95% confidence intervals (CIs) were calculated and the pooled analyses were performed with RevMan 5.3 software.Twenty-nine studies from 19 RCTs comprising of 16,724 patients (8115 patients in the SES group and 8609 patients in the PES group) satisfied the inclusion criteria and were included in this meta-analysis. No significant differences in ST have been observed between SES and PES. Results were as follow: definite ST with OR: 0.87; 95% CI: 0.64-1.18, P = 0.36; probable ST with OR:0.72; 95% CI: 0.42-1.21, P = 0.21; definite, probable and/or possible ST with OR: 0.94; 95% CI: 0.75-1.17, P = 0.57; acute ST with OR: 0.99; 95% CI: 0.38-2.56, P = 0.98; subacute ST with OR: 0.72; 95% CI: 0.41-1.25, P = 0.25; early ST with OR: 0.81; 95% CI: 0.53-1.25, P = 0.34; late ST with OR: 0.72; 95% CI: 0.39-1.34, P = 0.30; very late ST with OR: 1.02; 95% CI: 0.72-1.44, P = 0.92; and any ST with OR: 0.86; 95% CI: 0.69-1.07, P = 0.18. Long-term ST between 1 and 5 years with OR: 0.93; 95% CI: 0.71-1.22, P = 0.60 was also not significantly different.No significant difference in ST has been observed between patients treated with either SES or PES. Hence SES and PES can both be considered almost equally effective.

Assessment of vascular response after drug-eluting stents implantation in patients with diabetes mellitus: an optical coherence tomography sub-study of the J-DESsERT

Even in the drug-eluting stent era, diabetes mellitus (DM) patients have high incidences of restenosis and repeat revascularization after percutaneous coronary intervention. The aim of this study was to compare vascular response after stent implantation between sirolimus-eluting stent (SES) and paclitaxel-eluting stent (PES) by using optical coherence tomography (OCT) in DM patients as well as in non-DM patients. In the Japan-Drug Eluting Stents Evaluation; a Randomized Trial (J-DESsERT), the OCT sub-study enrolled 75 patients who underwent 8 months follow-up imaging after SES or PES implantation. Mean neointimal hyperplasia (NIH) thickness was significantly thinner in SES than PES in the DM group (77 ± 47 vs. 201 ± 114 μm, p < 0.001) and in the non-DM group (84 ± 37 vs. 212 ± 128 μm, p < 0.001). Unevenness of NIH thickness in longitudinal axis was significantly smaller in SES than PES in the DM group (348 ± 191 vs. 726 ± 385 μm, p < 0.001) and in the non-DM group (344 ± 174 vs. 679 ± 314 μm, p < 0.001). The percentage of uncovered struts was significantly greater in SES than PES in the DM group (24 ± 4 vs. 9 ± 14 %, p < 0.001) and in the non-DM group (16 ± 16 vs. 3 ± 4 %, p = 0.002). Compared with PES, SES showed more potent NIH inhibition in DM patients as well as in non-DM patients.

Update on drug-eluting coronary stents

The introduction of drug-eluting stents (DES) to interventional cardiology practice has resulted in a significant improvement in the long-term efficacy of percutaneous coronary interventions. DES successfully combine mechanical benefits of bare-metal stents and stabilizing the lumen, with direct delivery and the controlled elution of a pharmacologic agent to the injured vessel wall to suppress further neointimal proliferation. The dramatic reduction in restenosis has resulted in the implementation of DES in clinical practice, and has rapidly expanded the whole spectrum of successfully treatable coronary conditions, particularly in high-risk patients and complex lesions. In this review the authors present current data on DES. Currently, two types of DES are available in the USA: sirolimus-eluting stents (SES) CYPHER (Cordis Corp., FL, USA) and paclitaxel-eluting stents (PES) TAXUS (Boston Scientific, MA, USA), and many more are on the way to approval. In addition to sirolimus and paclitaxel, several other drugs have been successfully used in DES. Everolimus and ABT-578 are both analogs of sirolimus that also have immunosuppressive and antiproliferative properties. Another approach in the development of DES is to use drugs that can accelerate re-endothelialization and restore normal endothelial function following vascular injury. Recent advances in vascular gene transfer have also demonstrated potential new treatment modalities for cardiovascular disease, particularly in the treatment of vascular restenosis.

Safety and efficacy outcomes of first and second generation durable polymer drug eluting stents and biodegradable polymer biolimus eluting stents in clinical practice: comprehensive network meta-analysis

OBJECTIVES

To investigate the safety and efficacy of durable polymer drug eluting stents (DES) and biodegradable polymer biolimus eluting stents (biolimus-ES).

DESIGN

Network meta-analysis of randomised controlled trials.

DATA SOURCES AND STUDY SELECTION

Medline, Google Scholar, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) database search for randomised controlled trials comparing at least two of durable polymer sirolimus eluting stents (sirolimus-ES) and paclitaxel eluting stents (paclitaxel-ES), newer durable polymer everolimus eluting stents (everolimus-ES), Endeavor and Resolute zotarolimus eluting stents (zotarolimus-ES), and biodegradable polymer biolimus-ES.

PRIMARY OUTCOMES

Safety (death, myocardial infarction, definite or probable stent thrombosis) and efficacy (target lesion and target vessel revascularisation) assessed at up to one year and beyond.

RESULTS

60 randomised controlled trials were compared involving 63,242 patients with stable coronary artery disease or acute coronary syndrome treated with a DES. At one year, there were no differences in mortality among devices. Resolute and Endeavor zotarolimus-ES, everolimus-ES, and sirolimus-ES, but not biodegradable polymer biolimus-ES, were associated with significantly reduced odds of myocardial infarction (by 29-34%) compared with paclitaxel-ES. Compared with everolimus-ES, biodegradable polymer biolimus-ES were associated with significantly increased odds of myocardial infarction (by 29%), while Endeavor zotarolimus-ES and paclitaxel-ES were associated with significantly increased odds of stent thrombosis. All investigated DES were similar with regards to efficacy endpoints, except for Endeavor zotarolimus-ES and paclitaxel-ES, which were associated with significantly increased the odds of target lesion and target vessel revascularisations compared with other devices. Direction of results beyond one year did not diverge from the findings for up to one year follow-up. Bayesian probability curves showed a gradient in the magnitude of effect, with everolimus-ES and Resolute zotarolimus-ES offering the highest safety profiles.

CONCLUSIONS

The newer durable polymer everolimus-ES and Resolute zotarolimus-ES and the biodegradable polymer biolimus-ES maintain the efficacy of sirolimus-ES; however, for safety endpoints, differences become apparent, with everolimus-ES and Resolute zotarolimus-ES emerging as the safest stents to date.

Differences in clinical and angiographic outcomes with different drug-eluting stents in Japanese patients with and without diabetes mellitus

BACKGROUND

Although percutaneous coronary intervention (PCI) in patients with diabetes mellitus (DM) is associated with worse clinical outcomes, the efficacy of drug-eluting stents (DES) in Japanese patients and differences in effectiveness between different DES types remain unknown.

METHODS AND SUBJECTS

Five-hundred and sixty-two consecutive patients (183 with DM, 379 without DM) with 676 lesions were treated with sirolimus-eluting stents (SES, n=531; 160 DM group, 371 non-DM group) or paclitaxel-eluting stents (PES, n=145; 64 and 81, respectively). We assessed the initial and 8-month follow-up clinical and angiographic outcomes.

RESULTS

There were no significant differences in clinical and lesion characteristics, although the pre-minimum luminal diameter was smaller in the DM group (p=0.016). The risk of major adverse cardiac events (MACE), defined as cardiac death, non-fatal myocardial infarction, congestive heart failure, or recurrent angina pectoris, was higher in the DM group compared with the non-DM group (17.4% vs 9.5%, p=0.007). Among diabetic patients, although SES reduced late loss by 0.45 mm (p<0.001) and the binary restenosis rate by 66.4% (7.4% vs 22.0%, p<0.001) compared with PES at 8 months, it did not reduce target lesion revascularization or MACE, as in the non-DM group.

CONCLUSIONS

Diabetic patients have worse mid-term prognosis than non-diabetic patients undergoing PCI with DES. Although the superiority of SES in terms of late loss or restenosis may not play a clinically meaningful role in the treatment of diabetic patients, this phenomenon was independent of the presence of diabetes.

Outcomes with various drug eluting or bare metal stents in patients with diabetes mellitus: mixed treatment comparison analysis of 22,844 patient years of follow-up from randomised trials

OBJECTIVES

To evaluate the efficacy and safety of currently used drug eluting stents compared with each other and compared with bare metal stents in patients with diabetes.

DESIGN

Mixed treatment comparison meta-analysis.

DATA SOURCES AND STUDY SELECTION

PubMed, Embase, and CENTRAL were searched for randomised clinical trials, until April 2012, of four durable polymer drug eluting stents (sirolimus eluting stents, paclitaxel eluting stents, everolimus eluting stents, and zotarolimus eluting stents) compared with each other or with bare metal stents for the treatment of de novo coronary lesions and enrolling at least 50 patients with diabetes.

PRIMARY OUTCOMES

Efficacy (target vessel revascularisation) and safety (death, myocardial infarction, stent thrombosis).

RESULTS

From 42 trials with 22,844 patient years of follow-up, when compared with bare metal stents (reference rate ratio 1) all of the currently used drug eluting stents were associated with a significant reduction in target vessel revascularisation (37% to 69%), though the efficacy varied with the type of stent (everolimus eluting stents~sirolimus eluting stents>paclitaxel eluting stents~zotarolimus eluting stent>bare metal stents). There was about an 87% probability that everolimus eluting stents were the most efficacious compared with all others, though there were limited usable data for the zotarolimus eluting Resolute stent in patients with diabetes. Moreover, there was no increased risk of any safety outcome (including very late stent thrombosis) with any drug eluting stents compared with bare metal stents. There was about a 62% probability that the everolimus eluting stent was the safest stent for the outcome of "any" stent thrombosis.

CONCLUSIONS

Among patients with diabetes treated with coronary stents all currently available drug eluting stents were efficacious without compromising safety compared with bare metal stents. There were relative differences among the drug eluting stents, such that the everolimus eluting stent was the most efficacious and safe.

Short- and long-term outcomes with drug-eluting and bare-metal coronary stents: a mixed-treatment comparison analysis of 117 762 patient-years of follow-up from randomized trials

BACKGROUND

Drug-eluting stents (DES) have been in clinical use for nearly a decade; however, the relative short- and long-term efficacy and safety of DES compared with bare-metal stents (BMS) and among the DES types are less well defined.

METHODS AND RESULTS

PubMed, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) were searched for randomized clinical trials, until March 2012, that compared any of the Food and Drug Administration-approved durable stent and polymer DES (sirolimus-eluting stent [SES], paclitaxel-eluting stent [PES], everolimus-eluting stent [EES], zotarolimus-eluting stent [ZES], and ZES-Resolute [ZES-R]) with each other or against BMS for de novo coronary lesions, enrolling at least 100 patients and with follow-up of at least 6 months. Short-term (≤ 1 year) and long-term efficacy (target-vessel revascularization, target-lesion revascularization) and safety (death, myocardial infarction, stent thrombosis) outcomes were evaluated and trial-level data pooled by both mixed-treatment comparison and direct comparison analyses. From 76 randomized clinical trials with 117 762 patient-years of follow-up, compared with BMS, each DES reduced long-term target-vessel revascularization (39%-61%), but the magnitude varied by DES type (EES~SES~ZES-R>PES~ZES>BMS), with a >42% probability that EES had the lowest target-vessel revascularization rate. There was no increase in the risk of any long-term safety outcomes, including stent thrombosis, with any DES (versus BMS). In addition, there was reduction in myocardial infarction (all DES except PES versus BMS) and stent thrombosis (with EES versus BMS: Rate ratio, 0.51; 95% credibility interval, 0.35-0.73). The safest DES appeared to be EES (>86% probability), with reduction in myocardial infarction and stent thrombosis compared with BMS. Short-term outcomes were similar to long-term outcomes, with SES, ZES-R, and everolimus-eluting stent being the most efficacious and EES being the safest stent.

CONCLUSIONS

DES are highly efficacious at reducing the risk of target-vessel revascularization without an increase in any safety outcomes, including stent thrombosis. However, among the DES types, there were considerable differences, such that EES, SES, and ZES-R were the most efficacious and EES was the safest stent.

Intra-individual head-to-head comparison of Sirolimus®- and Paclitaxel®-eluting stents for coronary revascularization. A randomized, multi-center trial

BACKGROUND

Despite the known effects of drug-eluting stents (DES), other cofactors attributed to patient characteristics affect their success. Interest focused on designing a study minimizing these factors to answer continuing concerns on the heterogeneity of response to different DESs. The study's aim was to investigate the feasibility and impact of an intra-individual comparison design in patients (pts) with two coronary artery stenosis treated with a Sirolimus- (SES) and a Paclitaxel- (PES) eluting stent.

METHODS AND RESULTS

The study was conducted as a prospective, randomized, multi-center trial in 112 pts who consented to treatment with a SES and a PES. Pts were eligible if they suffered from the presence of two single primary target lesions in two different native coronary arteries. Lesions were randomized to either SES or PES treatment. The primary endpoint was in-stent luminal late loss (LLL), as determined by quantitative angiography at 8 months; clinical follow up was obtained at 1, 8, and 12 months additionally. The LLL (0.13 ± 0.28 mm SES vs. 0.26 ± 0.35 mm PES, p=0.011) showed less neointima in SES. With a predefined cut-off criterion of 0.2mm difference in LLL, 53/87 pts SES and PES were similar effective. 34/87 pts had a divergent result, 26 pts had greater benefit from SES while 8 pts had greater benefit from PES. Overall, MACE (MI, TLR, and death) occurred in 19 (17%) pts. Based on lesion analysis of 108 lesions treated with SES and 110 lesions treated with PES, 5 (4.6%) lesions with SES and 3 (2.7%) lesions with PES required repeated TLR.

CONCLUSION

An intra-individual comparison design to assess differences in efficacy of different DESs is feasible, safe and achieves similar results to inter-individual studies. This study is among the first to show that failure of one DES does not necessarily implicate failure of another DES and vice versa.

Everolimus-eluting versus sirolimus-eluting stents in patients undergoing percutaneous coronary intervention: the EXCELLENT (Efficacy of Xience/Promus Versus Cypher to Reduce Late Loss After Stenting) randomized trial

OBJECTIVES

The goal of this study was to compare the angiographic outcomes of everolimus-eluting stents (EES) and sirolimus-eluting stents (SES) in a head-to-head manner.

BACKGROUND

EES have been shown to be superior to paclitaxel-eluting stents in inhibiting late loss (LL) and clinical outcome. Whether EES may provide similar angiographic and clinical outcomes compared with SES is undetermined.

METHODS

This was a prospective, randomized, open-label, multicenter trial to demonstrate the noninferiority of EES compared with SES in preventing LL at 9 months. A total of 1,443 patients undergoing percutaneous coronary intervention were randomized 3:1 to receive EES or SES. Routine follow-up angiography was recommended at 9 months. The primary endpoint was in-segment LL at 9 months, and major secondary endpoints included in-stent LL at 9 months, target lesion failure, cardiac death, nonfatal myocardial infarction, target lesion revascularization, and stent thrombosis at 12 months. Data were managed by an independent management center, and clinical events were adjudicated by an independent adjudication committee.

RESULTS

Clinical follow-up was available in 1,428 patients and angiographic follow-up in 924 patients (1,215 lesions). The primary endpoint of the study (in-segment LL at 9 months) was 0.11 ± 0.38 mm and 0.06 ± 0.36 mm for EES and SES, respectively (p for noninferiority = 0.0382). The in-stent LL was also noninferior (EES 0.19 ± 0.35 mm; SES 0.15 ± 0.34 mm; p for noninferiority = 0.0121). The incidence of clinical endpoints was not statistically different between the 2 groups, including target lesion failure (3.75% vs. 3.05%; p = 0.53) and stent thrombosis (0.37% vs. 0.83%; p = 0.38).

CONCLUSIONS

EES were noninferior to SES in inhibition of LL after stenting, which was corroborated by similar rates of clinical outcomes. (Efficacy of Xience/Promus Versus Cypher in Reducing Late Loss After Stenting [EXCELLENT]; NCT00698607).

Drug-eluting stents for coronary artery disease: a review

Over the past decade the introduction of drug-eluting stents (DESs) has revolutionised the treatment of coronary artery disease. However, in recent years concern has arisen over the long-term safety and efficacy of DESs due to the occurrence of late adverse clinical events such as stent thrombosis. With this concern in mind, research and development is currently centred on increasing the long-term safety and efficacy of DESs. The aim of this paper is to provide a thorough review of currently approved and promising investigational DESs. With dozens of companies involved in the development of new and innovative anti-restenotic agents, polymeric coatings and stent platforms, it is intended that this review paper will provide a clear indication of how DESs are currently evolving and prove a valuable reference tool for future research in this area.

Long-term outcomes of sirolimus-eluting stents vs. paclitaxel-eluting stents in unprotected left main coronary artery bifurcation lesions

BACKGROUND

The treatment of unprotected left main coronary artery (uLMCA) bifurcation lesions remains challenging.

HYPOTHESIS

We hypothesized that the type of drug-eluting stent would correlate with clinical outcomes for the treatment of uLMCA bifurcation lesions.

METHODS

One hundred fifteen patients who underwent stent implantation using a provisional T-stenting technique with sirolimus-eluting stents (SES) or paclitaxel-eluting stents (PES) for uLMCA bifurcation lesions were enrolled. A major adverse cardiac event (MACE) was defined as a composite of cardiac death, myocardial infarction, or target lesion revascularization.

RESULTS

Ninety-four patients were treated with SES and 21 patients with PES. Baseline characteristics were similar between the 2 groups. Angiographic follow-up was performed in 99 (86%) patients. Late loss in the LMCA to the left anterior descending coronary artery was significantly lower in the SES group than in the PES group (0.28 ± 0.54 mm vs 1.03 ± 0.45 mm, P<0.001). One case of stent thrombosis occurred in the SES group. During follow-up with a median of 712 days, the SES group had a lower MACE compared with the PES group (10.6% vs. 28.6%, P = 0.032). Cox proportional hazards models including age, sex, diabetes, acute coronary syndrome, true bifurcation, stenting strategy, and type of drug-eluting stent used (SES vs. PES) demonstrated that stent type was the only predictor of MACE (hazard ratio of PES vs SES: 3.88, 95% confidence interval: 1.29-11.67, P = 0.016).

CONCLUSIONS

According to the results of the present study, SES may be associated with more favorable outcomes than PES for stenting of uLMCA bifurcation, which should be further studied by larger trials.

How safe and how good are drug-eluting stents?

Percutaneous transluminal coronary angioplasty revolutionized therapy for coronary artery disease. This early promise of a viable alternative to surgical treatment of coronary artery disease was thwarted by the high rates of angiographic restenosis. The advent of stenting reduced the rates of restenosis, although it was hindered by the new problem of in-stent restenosis. It was demonstrated that in-stent restenosis was the result of a new pathology in the form of neointimal hyperplasia, which was a maladaptive healing response to bare-metal stent implantation. Recently, the introduction of drug-eluting stents (DES) technology has offered a new solution to the problem of restenosis. Current evidence suggests that although DES have reduced restenosis rates, important concerns have been raised regarding increased stent thrombosis, myocardial infarction and death. The purpose of this article is to examine the efficacy and safety data of DES as highlighted in recent publications and to further discuss the biomolecular mechanisms of accelerated endothelization and stent thrombosis. In addition, we will examine some of the newer stent technologies available.

Surface grafting of blood compatible zwitterionic poly(ethylene glycol) on diamond-like carbon-coated stent

Blood compatibility is the most important aspect for blood-contacting medical devices including cardiovascular stents. In this study, the surface of nickel-titanium (TiNi) stent was coated with diamond-like carbon (DLC) and then subsequently grafted by using zwitterion (N(+) and SO(3) (-))-linked poly(ethylene glycol) (PEG). We hypothesize that this coupling of zwitterion and PEG may significantly improve blood compatibility of DLC-coated TiNi stent. The surface modified TiNi stents, including PEG-grafted stent (DLC-PEG) and zwitterionic PEG-grafted one (DLC-PEG-N-S) were the main focus on the tests of surface characteristics and blood compatibility. The zwitterionic PEG derivatives were obtained from a series of chemical reactions at room temperature. The results exhibited that as compared to the DLC-PEG, the hydrophilicity was much better with DLC-PEG-N-S and significantly increased atomic percentage of oxygen and nitrogen proved the entity of zwitterions on the surface of DLC-PEG-N-S. Meanwhile, the adsorption of blood proteins such as, human serum albumin (HSA) and fibrinogen was found considerably down-regulated in DLC-PEG-N-S, due mainly to the protein-repellent effect of PEG and zwitterion. Microscopic observation also revealed that as compared with the other substrates without zwitterion, the degree of platelet adhesion was the lowest with DLC-PEG-N-S. In addition, DLC-PEG-N-S retained an extended blood coagulation time as measured by activated partial thromboplastin time (APTT). The present results suggested that surface grafting of zwitterionic PEG derivatives could substantially enhance the blood compatibility of TiNi-DLC stent. In conclusion, anti-fouling properties of PEG and zwitterions are expected to be very useful in advancing overall stent performance.

High soluble Fas and soluble Fas Ligand serum levels before stent implantation are protective against restenosis

Percutaneous coronary intervention (PCI) represents the most important treatment of coronary artery stenosis today. But instent restenosis (ISR) is a limitation for the outcome. Fas and Fas Ligand have been implicated in apoptosis and vessel wall inflammation. Their role in ISR is not known so far. In this prospective study we studied 137 patients with stable coronary artery disease who underwent elective PCI. Blood samples were taken directly before and 24 hours after PCI. Soluble (s)Fas and sFas Ligand serum levels were measured by ELISA. Restenosis was evaluated six to eight months later either by coronary angiography or by exercise testing. During the follow-up period, 18 patients (13%) developed ISR. At baseline, patients with ISR had significantly lower median sFas, as well as sFas Ligand levels compared to patients without ISR (sFAS: ISR 492 pg/ml, no ISR 967 pg/ml, p=0.014; sFAS Ligand: ISR: 26 pg/ml, no ISR: 42 pg/ml, p=0.001). After PCI median sFas levels significantly decreased in patients with ISR compared to patients without ISR [ISR: -152 pg/ml (IQR -36 to -227), no ISR: -38 pg/ml (IQR -173 to +150 pg/ml), p=0.03]. sFas Ligand levels after PCI significantly increased in ISR patients compared to patients without ISR [ISR: 14 pg/ml (IQR -3 to +26 pg/ml), no ISR -6 pg/ml (IQR -22 to +21 pg/ml), p=0.014]. In conclusion, sFas and sFas Ligand seem to be associated with the development of ISR. Determination of serum levels before and after PCI might help identifying patients at higher risk of ISR.

The unrestricted use of sirolimus- and paclitaxel-eluting stents results in better clinical outcomes during 6-year follow-up than bare-metal stents: an analysis of the RESEARCH (Rapamycin-Eluting Stent Evaluated At Rotterdam Cardiology Hospital) and T-SEARCH (Taxus-Stent Evaluated At Rotterdam Cardiology Hospital) registries

OBJECTIVES

The aim of this study was to assess the 6-year clinical outcome after unrestricted use of sirolimus-eluting stents (SES) or paclitaxel-eluting stents (PES) as compared with bare-metal stents (BMS) in consecutive de novo patients undergoing percutaneous coronary intervention (PCI).

BACKGROUND

SES and PES have been shown to significantly decrease target vessel revascularization (TVR) rates compared with BMS in "real-world" registries. However, possible higher rates of very-late stent thrombosis and a restenosis "catch-up" trend might jeopardize the benefit.

METHODS

Three PCI cohorts, each with exclusive use of 1 stent type (BMS = 450; SES = 508; PES = 576), were systematically followed for the occurrence of major adverse cardiac events (MACE).

RESULTS

Very-late stent thrombosis was more common in SES and PES patients than BMS patients (2.4% vs. 0.9% vs. 0.4%, respectively; p = 0.02); however, there were no significant differences between the stent types for all-cause mortality and all-cause mortality/myocardial infarction at 6-year follow-up. Sixty-nine SES patients (Kaplan-Meier estimate 14%) and 72 PES patients (14%) had a TVR, as compared with 79 BMS patients (18%; log-rank p = 0.02), which maintained significance after adjustment for (potential) confounders. Multivariate analysis showed that DES implantation is associated with lower incidence of TVR and MACE than BMS implantation (hazard ratio: 0.65, 95% confidence interval: 0.49 to 0.86; p = 0.003; hazard ratio: 0.79, 95% confidence interval: 0.65 to 0.97; p = 0.02, respectively). Incidence of MACE was also lower in SES and PES patients (30% and 30%, respectively) than in BMS patients (34%); however, significance was borderline.

CONCLUSIONS

The unrestricted use of both DES resulted in a sustained advantage in decreasing TVR and, to a lesser extent, MACE compared with BMS at 6 years. The SES and PES are equally safe and effective in the treatment of coronary lesions.

Four-year clinical outcome of sirolimus- and paclitaxel-eluting stents compared to bare-metal stents for the percutaneous treatment of stable coronary artery disease

BACKGROUND

There are limited data on the long-term safety and efficacy profile of coronary stent implantation in patients with stable coronary artery disease (CAD) undergoing percutaneous coronary intervention (PCI).

OBJECTIVE

We aimed to assess the 4-year clinical outcome in patients who received a bare-metal stent (BMS), sirolimus-eluting stent (SES), or a paclitaxel-eluting stent (PES) for the percutaneous treatment of stable angina in our center during 2000-2005.

METHODS

In the study period, a total of 2,449 consecutive patients (BMS = 1,005; SES = 373; and PES = 1071) underwent a PCI as part of three historical PCI-cohorts for stable angina and were routinely followed for the occurrence of major adverse cardiac events (MACE).

RESULTS

At 4 years follow-up, 264 BMS patients (26.8%) had a MACE, compared to 75 SES patients (20.9%) and 199 PES patients (23.9%). Multivariate analysis showed that SES and PES were superior to BMS with respect to MACE [hazard ratio (HR) = 0.62, 95% confidence interval (CI): 0.47-0.81; HR = 0.67, 95% CI: 0.55-0.82, respectively]. The occurrence of MACE was significantly lower in the SES and PES population, primarily due to less target-vessel revascularization (TVR) procedures (HR = 0.53, 95% CI: 0.37-0.75; HR = 0.71, 95% CI: 0.62-0.81, respectively). The occurrence of early, late, and very late stent thrombosis was equally rare with each stent type. There were no significant differences between SES and PES on death, myocardial infarction, TVR, and MACE.

CONCLUSION

These findings suggest that SES and PES result in decreased TVR procedures and MACE compared to BMS at 4 years follow-up. SES or PES implantation should be the preferred choice over BMS for patients with stable CAD undergoing PCI.

Outcomes after differential use of drug-eluting stents in diabetic patients: 1-year results from the DES.DE (Drug-Eluting Stent.DEutschland) registry

OBJECTIVES

The prospective multicenter German DES.DE registry provides real world data to evaluate the therapeutic principle of two different drug-eluting stents (DES) [Sirolimus- (SES) and Paclitaxel-eluting stent (PES)] in the context of the German Health System.

BACKGROUND

Differential DES have been effective in randomized trials, but their difference in safety and efficacy in diabetic patients has not been well studied.

METHODS

Baseline, predefined procedural as well as clinical in-hospital and follow-up events were recorded for all 1,526 diabetic patients. The composite of death, myocardial infarction (MI), and stroke defined as major adverse cardiac and cerebrovascular events (MACCE) and target vessel revascularization (TVR) were defined as primary endpoints.

RESULTS

Between October 2005 and October 2006, 1,526 diabetic patients, 34.2% of them being insulin-dependent, were enrolled (SES: n = 612; PES: n = 914) at 98 DES.DE sites. Overall, one third of patients were admitted with acute coronary syndrome (ACS) and 70% had multivessel-disease reflecting a real world scenario. With similar baseline clinical and descriptive morphology of coronary artery disease (CAD) in both DES groups, there were no statistical differences in 1-year follow-up with respect to rates of overall mortality (5.8% vs. 5.4%), TVR (12.0% vs. 11.3%), overall stent thrombosis (5.6% vs. 4.6%) and MACCE (11.4% vs. 10.3%) between both DES.

CONCLUSION

The data collected in DES.DE revealed no differences in clinical outcomes within 1 year between SES and PES in diabetic patients in a "real-world" setting.

Recent progress in percutaneous coronary intervention: evolution of the drug-eluting stents, focus on the XIENCE V drug-eluting stent

Although originally the practice of using balloon catheters proved successful in the short term, the long-term prognosis was less promising because of restenosis, which occurred in >or=30% of patients. This prompted the development of new techniques and mechanical adjuncts, or stents, to maintain lumen patency after balloon angioplasty. Bare metal stents (BMS), the first type of stent used in percutaneous coronary intervention, were designed to address the issues met by balloon angioplasty. BMS reduced the angiographic and clinical restenosis rates in de novo lesions compared to percutaneous transluminal coronary angioplasty alone and decreased the need for emergency coronary artery bypass graft surgery. BMS substantially reduced the incidence of abrupt artery closure, but restenosis still occurred after 6 months in about 20% of cases, necessitating repeat procedures. Drug-eluting stents (DES) improved on the principle of BMS by also delivering drugs locally to inhibit neointimal hyperplasia. DES greatly reduced the incidence of restenosis and resulted in a better safety profile as compared to radiation or systemic drug administration. These advantages and a lower cost compared to surgical interventions make DES an attractive option to treat coronary artery disease. Currently, five DES are available in the USA: the CYPHER sirolimus-eluting stent from Cordis (approved by FDA on 24 April 2003), the TAXUS Express(2) and Liberté paclitaxel-eluting stents from Boston Scientific (approved by FDA on 4 March 2004 and 10 October 2008, respectively) (hereafter TAXUS Express is referred to as TAXUS), the ENDEAVOR zotarolimus-eluting stent from Medtronic (approved by FDA on 1 February 2008), and the XIENCE V everolimus-eluting stent from Abbott Vascular (approved by FDA on 2 July 2008). Following the approval of CYPHER and TAXUS, the clinical data suggested a potential small increase in the rate of stent thrombosis (ST) in DES compared with BMS after implantation. To determine the differences in ST and other rare events between different stents, some modifications have been made to DES clinical trial design, and postmarket surveillance programs have been included to further evaluate the safety and efficacy of each DES. In this review, we will discuss the key clinical outcomes of DES clinical trials, design and key features of the current coronary stents, and major clinical development programs. Postmarket trials, designed to establish long-term safety around ST and other rare clinical events, are also discussed. The future of DES design technologies will also be outlined.

SPIRIT IV trial design: a large-scale randomized comparison of everolimus-eluting stents and paclitaxel-eluting stents in patients with coronary artery disease

BACKGROUND

In the 300-patient SPIRIT II and 1002-patient SPIRIT III randomized trials, the everolimus-eluting stent (EES) compared to the paclitaxel-eluting stent (PES) resulted in reduced angiographic late loss (a primary end point in both trials), noninferior rates of 9-month target vessel failure (a primary end point in SPIRIT III), and reduced rates of target lesion revascularization and major adverse cardiac events (secondary end points). However, neither trial was powered for superiority for clinical end points, and the routine performance of angiographic follow-up may have artificially exaggerated the absolute benefits of EES. The relative efficacy of these 2 stents in patients with diabetes mellitus also remains controversial. We therefore designed a large-scale randomized trial without angiographic follow-up to further assess the differences between these 2 stent platforms.

STUDY DESIGN

SPIRIT IV is an ongoing prospective, active-controlled, single-blinded, multicenter clinical trial in which 3690 patients with native coronary artery disease have been randomized 2:1 to EES versus PES. Patients with up to 3 de novo native coronary artery lesions (maximum 2 lesions per epicardial vessel) with length <or=28 mm and reference vessel diameter >or=2.5 to <or=4.25 mm were enrolled at 66 US clinical sites. Clinical follow-up at 30, 180, and 270 days; 1 year; and then yearly for up to 5 years is underway. The primary end point is the rate of ischemia-driven target lesion failure at 1 year, a composite measure of safety and efficacy consisting of cardiac death, target vessel myocardial infarction, or ischemia-driven target lesion revascularization, with the trial powered for sequential noninferiority and superiority testing.

SUMMARY

SPIRIT IV is the largest randomized comparison of 2 DES with completed enrollment. The absence of routine angiographic follow-up will allow an accurate assessment of the absolute differences in the clinical safety and efficacy profile between these devices. The magnitude of the study will also permit significant insights to be gained into the relative performance of the 2 stents in important subgroups, including patients with diabetes mellitus.

Efficacy of Xience/promus versus Cypher in rEducing Late Loss after stENTing (EXCELLENT) trial: study design and rationale of a Korean multicenter prospective randomized trial

BACKGROUND

The everolimus-eluting stent (EES) is a newly developed drug-eluting stent using the MULTILINK VISION stent platform combined with the drug everolimus contained in a polymer coating. Recently reported randomized trials have shown the noninferiority and subsequent superiority of the EES compared with the paclitaxel-eluting stent regarding in-stent late loss (LL) at 180 days. However, there have been no studies comparing head to head the EES with the sirolimus-eluting stent (SES), which has shown the least amount of LL among the previously released drug-eluting stent (DES). In addition, adjunctive antiplatelet therapy is a critical factor in optimizing long-term DES safety. Despite the recommendation of the American Heart Association/American College of Cardiology to maintain 12 months of dual antiplatelet therapy, there have been no prospective randomized trials comparing the efficacy and safety of different durations.

STUDY DESIGN

In the Efficacy of Xience/promus versus Cypher in rEducing Late Loss after stENTing (EXCELLENT) trial, approximately 1,400 patients are being prospectively and randomly assigned in a 2 x 2 factorial design according to the type of stent (EES vs SES) and the duration of dual antiplatelet therapy (6 vs 12 months). The primary end point is in-segment LL at 9 months for comparison of type of stent, and the coprimary end point is target vessel failure at 12 months for comparison of dual antiplatelet therapy duration.

SUMMARY

The EXCELLENT trial is the largest study yet performed to directly compare the efficacy and safety of the EES versus the SES. In addition, this study will also address the issue of a 6- versus 12-month duration of dual antiplatelet therapy for post-percutaneous coronary intervention management.

One-year outcomes from the TAXUS express stent versus cypher stent

We compared 1-year outcomes in patients treated with paclitaxel-eluting stents (PESs) or sirolimus-eluting stents (SESs) in "real-world" clinical practice. Clinical outcomes were evaluated in 1,558 consecutive, unselected, retrospectively collected patients treated with drug-eluting stents (DESs; PES = 816, SES = 742) at 19 United States centers. The primary end point was 1-year target vessel revascularization (TVR). The study included a prespecified diabetic cohort (PES = 289, SES = 247), for which efficacy comparisons between DESs were analyzed according to vessel diameter and presence of chronic kidney disease. Baseline demographic, angiographic, and procedural characteristics were similar between patients treated with PESs and those treated with SESs. At 1 year, there were no overall statistical differences in death, myocardial infarction, TVR, or stent thrombosis. In the diabetic cohort, however, the cumulative incidence of TVR was significantly lower for patients treated with PESs (3%) compared with SESs (9%, p <0.01), which persisted after adjustment for baseline differences (hazard ratio 0.29, 95% confidence interval 0.12 to 0.67). This decrease in TVR with PES was similar in insulin- and noninsulin-requiring diabetic patients. In multivariate analysis, independent predictors of TVR included diabetes, bifurcation stenting, and overlapping stents; in the diabetic cohort, treatment with SESs was also a multivariate predictor of TVR. In conclusion, in this observational, retrospective analysis of DES-treated patients, PESs and SESs demonstrated similar overall safety and efficacy, but PESs were associated with a significant decrease in 1-year TVR rates in diabetic patients.

Drug-eluting stents: a comprehensive appraisal

Cardiovascular medicine has evolved over the last few decades, with the advent of percutaneous interventional treatments. In particular, balloon angioplasty and, subsequently, coronary stenting has revolutionized our current perspective of stable and unstable coronary artery disease management. However, the long-term results of stent usage have been blighted by the dual problems of in-stent restenosis and stent thrombosis. Whilst stent thrombosis became much less frequent with the introduction of dual-antiplatelet therapy, restenosis remained a significant problem. Intense work on stent development has successfully led to the introduction of drug-eluting stents (DES) in an effort to address this problem. Randomized trials have consistently proven the superior efficacy of DES over bare metal stents, in elective patients, acute coronary syndromes and patients with diabetes mellitus. Nevertheless, the routine use of DES in by-pass venous graft disease remains debatable. The initial DES used sirolimus and paclitaxel are now being joined by newer stents releasing drugs, such as everolimus, zotarolimus and tacrolimus. Ongoing developments with the stent platform and the polymer coating are also gradually improving the performance of these stents in clinical practice. More recently, the idea of antibody-coated stents that would encourage epithelialization of stent struts by endothelial progenitor cells recruitment has gained attraction among interventionists, with a possible beneficial impact on reducing the incidence of restenosis.

Percutaneous coronary implantation of sirolimus-eluting stents in unselected patients and lesions: clinical results and multiple outcome predictors

BACKGROUND

Sirolimus-eluting stents (SES) prevent restenosis and repeat percutaneous coronary intervention (PCI), but safety data in unselected patients are limited, especially for intermediate-term follow-up.

METHODS

All patients undergoing SES implantation at 4 Italian centers were enrolled into a dedicated database. Baseline, procedural, and outcome data at discharge and at follow-up were abstracted. Outcomes of interest were the occurrence of major adverse cerebrocardiovascular events (MACCE) at 6 months, as well as long-term event-free survival and multivariable event predictors.

RESULTS

One thousand four hundred twenty-four patients were enrolled (2,915 lesions, treated with 3,305 stents). Specifically, 1,074 (75.4%) subjects had multivessel disease, 399 (28.1%) had diabetes, 89 (6.3%) had ST-elevation myocardial infarction, and 44 (3.1%) underwent unprotected left main intervention. At 6 months, MACCE had occurred in 121 (9.0%) patients. After a median of 48.7 months (first-third quartile 41.8-55.3), MACCE-free survival was 69.2%+/-2.6%, with definite stent thrombosis occurring acutely in 6 (0.4%), subacutely in 11 (0.8%), after 30 days in 12 (0.8%), and cumulatively in 28 (2.0%). Major multivariable outcome predictors were diabetes (target lesion revascularization [TLR], MACCE), ejection fraction (TLR, MACCE), and maximal balloon length (TLR).

CONCLUSIONS

This large cohort of unselected patients supports the overall safety of unrestricted percutaneous SES implantation, as shown by the low rates of stent thrombosis. Event attrition remains, however, high at long-term follow-up, driven mainly by target vessel revascularization, with diabetes and ejection fraction as the most important prognostic factors.

Prospective randomized comparison of sirolimus- versus paclitaxel-eluting stents for the treatment of acute ST-elevation myocardial infarction: pROSIT trial

OBJECTIVE

The aim of this study was to compare effectiveness of the Sirolimus- (SES) and Paclitaxel-eluting stent (PES) in primary angioplasty for acute ST-elevation myocardial infarction (STEMI).

BACKGROUND

It has been reported that SES and PES have been more effective than bare-metal stents in reducing restenosis and cardiac events in a broad range of patients with coronary artery disease. However, it is unknown whether there may be differences between these two drug-eluting stents in terms of efficacy in the setting of acute STEMI.

METHODS

Acute STEMI patients (n = 308) undergoing primary angioplasty were randomly assigned to SES (n = 154) or PES (n = 154) deployment. The routine angiographic follow-up was performed at 6 months and clinical follow-up data was obtained at 12 months. The primary end point was major adverse cardiac events (MACE) including death, reinfarction, stent thrombosis, and target lesion revascularization (TLR) at 12 months.

RESULTS

The baseline clinical, angiographic, and procedural characteristics were similar between the 2 groups. Two patients (all from the PES group) experienced stent thrombosis (1 acute and 1 subacute). The SES group revealed lower in-segment restenosis (5.9% vs. 14.8%, P = 0.03) and in-segment late loss (0.09 +/- 0.45 vs. 0.33 +/- 0.68 mm, P = 0.002) than PES group on follow-up angiography. Twelve-month TLR rates (2.6% vs. 6.5%, P = 0.17) were similar between two groups. MACE rates were lower in the SES group than in the PES group, but it did not reach statistical significance (5.8% vs. 11.7%, P = 0.07).

CONCLUSION

In the setting of primary angioplasty for STEMI, there were no statistically significant differences between the SES and the PES in terms of 12-month MACE. However, binary angiographic in-segment restenosis and in-segment late loss were significantly lower in the SES group.

A randomized comparison of sirolimus- versus Paclitaxel-eluting stent implantation in patients with diabetes mellitus

OBJECTIVES

The aim of this study was to compare the effectiveness of sirolimus-eluting stents (SES) and paclitaxel-eluting stents (PES) in patients with diabetes mellitus (DM).

BACKGROUND

Drug-eluting stent implantation significantly improved the angiographic and clinical outcomes compared with bare-metal stent implantation in diabetic patients. However, comparison of SES with PES in diabetic patients has not been sufficiently evaluated.

METHODS

This prospective, multicenter, randomized study compared SES (n = 200) and PES implantation (n = 200) for diabetic patients (n = 400). The primary end point was in-segment restenosis at 6 months according to intention-to-treat principle.

RESULTS

The 2 groups had similar baseline clinical and angiographic characteristics. Six-month in-stent (3.4% vs. 18.2%, p < 0.001) and in-segment restenosis (4.0% vs. 20.8%, p < 0.001) and 9-month target lesion revascularization (2.0% vs. 7.5%, p = 0.017) were significantly lower in the SES versus the PES group. The incidence of death (0% in SES vs. 0.5% in PES, p = 0.999) or myocardial infarction (0.5% in SES vs. 0.5% in PES, p = 0.999) at 9-month follow-up was not statistically different between the 2 groups. Major adverse cardiac events including death, myocardial infarction, and target lesion revascularization at 9 months (2.0% vs. 8.0%, p = 0.010) were lower in the SES versus the PES group.

CONCLUSIONS

Sirolimus-eluting stent implantation is superior in reducing angiographic restenosis and improving 9-month clinical outcomes in patients with DM and coronary artery disease compared with PES implantation.

Coronary in-stent restenosis in diabetic patients after implantation of sirolimus or paclitaxel drug-eluting coronary stents

It is now emerging that, in patients who are at high risk for cardiovascular complications and, in particular, those with diabetes, the occurrence of late restenosis and thrombosis after treatment of coronary artery disease with drug-eluting stents is higher than earlier reports have suggested. Therefore, the aim of this study was to assess the prevalence of in-stent restenosis in a cohort of consecutive patients with diabetes treated for coronary disease in 2005 with drug-eluting stents [either sirolimus (58%) or paclitaxel (42%)]. The duration of follow-up was 9.0+/-3.4 months [mean+/-1 standard deviation (S.D.)]. A total of 154 patients (type 2 diabetes: 91%) were included in the study (age: 66+/-10 years), and the total number of implanted stents was 184. Two subjects died from cardiac causes, while myocardial infarction and (un)stable angina were observed in 3 (2%) and 39 (25%) patients, respectively. In-stent restenosis, appraised by angiography, was observed in 17 individuals (11%) after a mean follow-up of five months. Mean HbA(1c) in patients with restenosis was 7.6+/-1.8%. There was no difference in the rate of restenosis with sirolimus-(n=8) compared with paclitaxel-(n=9) eluting stents. Male gender, oral therapy for diabetes and stent diameter were predictors of in-stent restenosis. In conclusion, even over a medium-term period, in-stent restenosis remains a potential risk for coronary diabetic patients treated with drug-eluting devices.

Intramural delivery of rapamycin with alphavbeta3-targeted paramagnetic nanoparticles inhibits stenosis after balloon injury

BACKGROUND

Drug eluting stents prevent vascular restenosis but can delay endothelial healing. A rabbit femoral artery model of stenosis formation after vascular injury was used to study the effect of intramural delivery of alpha(v)beta(3)-integrin-targeted rapamycin nanoparticles on vascular stenosis and endothelial healing responses.

METHODS AND RESULTS

Femoral arteries of 48 atherosclerotic rabbits underwent balloon stretch injury and were locally treated with either (1) alpha(v)beta(3)-targeted rapamycin nanoparticles, (2) alpha(v)beta(3)-targeted nanoparticles without rapamycin, (3) nontargeted rapamycin nanoparticles, or (4) saline. Intramural binding of integrin-targeted paramagnetic nanoparticles was confirmed with MR molecular imaging (1.5 T). MR angiograms were indistinguishable between targeted and control arteries at baseline, but 2 weeks later they showed qualitatively less luminal plaque in the targeted rapamycin treated segments compared with contralateral control vessels. In a first cohort of 19 animals (38 vessel segments), microscopic morphometric analysis of the rapamycin-treated segments revealed a 52% decrease in the neointima/media ratio (P<0.05) compared to control. No differences (P>0.05) were observed among balloon injured vessel segments treated with alpha(v)beta(3)-targeted nanoparticles without rapamycin, nontargeted nanoparticles with rapamycin, or saline. In a second cohort of 29 animals, endothelial healing followed a parallel pattern over 4 weeks in the vessels treated with alpha(v)beta(3)-targeted rapamycin nanoparticles and the 3 control groups.

CONCLUSIONS

Local intramural delivery of alpha(v)beta(3)-targeted rapamycin nanoparticles inhibited stenosis without delaying endothelial healing after balloon injury.

Comparative safety and efficacy of a sirolimus-eluting versus paclitaxel-eluting stent: a meta-analysis

BACKGROUND

Drug-eluting stents have emerged as the favored device for percutaneous coronary intervention. It is not clear if there are differences in the currently available drug-eluting stents. We performed a meta-analysis to systematically evaluate currently available data comparing sirolimus-eluting stents (SESs) with paclitaxel-eluting stents (PESs) in patients with coronary artery disease.

METHODS

We searched the MEDLINE, Embase, ISI Web of Knowledge, Current Contents, and International Pharmaceutical Abstracts databases, and the Cochrane Central Register of Controlled Trials, as well as scientific meeting abstracts up to November 30, 2006. All randomized controlled trials comparing SES with PES and providing follow-up data of > or = 6 months were eligible for inclusion in our analysis.

RESULTS

Data from 12 trials (number of patients 7455) were pooled. There was no difference in death (summary odds ratio [OR] 0.88, 95% CI 0.61-1.25, P = .46), myocardial infarction (summary OR 0.92, 95% CI, 0.71-1.19, P = .51), or stent thrombosis (summary OR 0.75, 95% CI 0.40-1.40, P = .37) between SES and PES. The use of SES was associated with a significant reduction in angiographic restenosis (summary OR 0.64, 95% CI 0.52-0.78, P < .001), target vessel revascularization (5.66% vs 7.70%, summary OR 0.72, 95% CI 0.59-0.88, P = .002), or target lesion revascularization (summary OR 0.67, 95% CI 0.53-0.84, P = .001).

CONCLUSIONS

Patients treated with SES appear to have a significantly lower risk of restenosis and need for target vessel revascularization compared with those treated with PES. There is no significant difference between the 2 stents with respect to mortality, myocardial infarction, or early stent thrombosis.

Changes in CCR2 chemokine receptor expression and plasma MCP-1 concentration after the implantation of bare metal stents versus sirolimus-eluting stents in patients with stable angina

BACKGROUND

Although restenosis after successful coronary stenting is associated with changes in adhesion molecules and chemokines, it is unclear whether the differential effects of these molecules between a bare metal stent (BMS) and sirolimus-eluting stent (SES) may help to prevent coronary restenosis. The aim of this clinical study was to compare the expression levels of those molecules after elective placement of either a BMS or SES.

METHODS AND RESULTS

The subjects included 32 consecutive patients with stable angina who had undergone successful coronary stenting and who randomly received either a BMS (n=16) or SES (n=16). Quantitative angiographic analysis 6 months after stenting showed that the minimal lumen diameter was significantly greater in the SES as compared to the BMS group, while the percent diameter stenosis and in-stent lumen loss were significantly lower. Plasma monocyte chemotactic protein-1 (MCP-1) increased significantly after 14 days and 6 months and monocyte CCR2 expression increased 24 hr and 48 hr after stenting in the BMS but not the SES group. Changes in plasma MCP-1 (DeltaMCP-1) within 6 months after stenting correlated significantly with in-stent lumen loss. The DeltaMCP-1 (between 6 months and baseline) was significantly related only to the lumen loss (r=0.443, p=0.023), which suggests that the reduction of MCP-1 is the best contributor to decreased lumen loss.

CONCLUSIONS

These data suggest that reduction in MCP-1 production by SES may be one mechanism to prevent restenosis after coronary stenting.

A Meta-Analysis of 16 Randomized Trials of Sirolimus-Eluting Stents Versus Paclitaxel-Eluting Stents in Patients With Coronary Artery Disease

OBJECTIVES

Our purpose was to make a synthesis of the available evidence on the relative efficacy and safety of 2 drug-eluting stents (DES)--sirolimus-eluting stent (SES) and paclitaxel-eluting stent (PES)--in patients with coronary artery disease.

BACKGROUND

It is not known whether there are differences in late outcomes between the 2 most commonly used DES: SES and PES.

METHODS

Sixteen randomized trials of SES versus PES with a total number of 8,695 patients were included in this meta-analysis. A full set of individual outcome data from 5,562 patients was also available. Mean follow-up period ranged from 9 to 37 months. The primary efficacy end point was the need for reintervention (target lesion revascularization). The primary safety end point was stent thrombosis. Secondary end points were death and recurrent myocardial infarction (MI).

RESULTS

No significant heterogeneity was found across trials. Compared with PES, SES significantly reduced the risk of reintervention (hazard ratio [HR] 0.74; 95% confidence interval [CI] 0.63 to 0.87, p < 0.001) and stent thrombosis (HR 0.66; 95% CI 0.46 to 0.94, p = 0.02) without significantly impacting on the risk of death (HR 0.92; 95% CI 0.74 to 1.13, p = 0.43) or MI (HR 0.84; 95% CI 0.69 to 1.03, p = 0.10).

CONCLUSIONS

Sirolimus-eluting stents are superior to PES in terms of a significant reduction of the risk of reintervention and stent thrombosis. The risk of death was not significantly different between the 2 DES, but there was a trend toward a higher risk of MI with PES, especially after the first year from the procedure.