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

Long-term safety of bioresorbable scaffolds: insights from a network meta-analysis including 91 trials

AIMS

The aim of this study was to investigate the long-term safety and efficacy of biodegradable scaffolds and metallic stents.

METHODS AND RESULTS

We analysed a total of 91 randomised controlled trials with a mean follow-up of 3.7 years in 105,842 patients which compared two or more coronary metallic stents or biodegradable scaffolds and reported the long-term clinical outcomes (≥2 years). Network meta-analysis showed that patients treated with the Absorb bioresorbable vascular scaffold (BVS) had a significantly higher risk of definite or probable scaffold thrombosis (ScT) compared to those treated with metallic DES. The risk of very late ScT was highest with the Absorb BVS among comparators. Pairwise conventional meta-analysis demonstrated that the elevated risk of ScT with Absorb BVS compared to cobalt-chromium everolimus-eluting stents was consistent across the time points of ≤30 days (early), 31 days - 1 year (late) and >1 year (very late) ScT. In addition, target lesion failure rates were significantly higher in the Absorb BVS cohort, driven by both increased risk of target vessel myocardial infarction and ischaemia-driven target lesion revascularisation.

CONCLUSIONS

Absorb BVS implantation was associated with increased risk of long-term and very late ScT compared to current-generation metallic DES. The risk of ScT occurred with a rising trend beyond one year.

Coronary Stents in Diabetic Patients: State of the Knowledge

PURPOSE OF REVIEW

This review article aims to summarize the findings of the most relevant research that compared the use of paclitaxel vs. "limus" based drug eluting stent (DES) in diabetic patients and to define the current state of knowledge with new stent technologies in this patient population.

RECENT FINDINGS

Since drug eluting stents (DES) were introduced, it has been of great interest to establish whether paclitaxel or sirolimus eluting stents have the same safety and efficacy features for patients with coronary artery disease. The answer to this question is particularly relevant for diabetic patients. Several randomized trials, registry-based studies, and meta-analyses have assessed the performance of these different DES in diabetic patients. The most recently published data favors limus over paclitaxel DES in diabetic patients, but most of these studies compared first vs. second generation DES with the inherent caveats of comparing different platforms, alloys, and drug delivery vehicles. In this literature review, we found that there is robust evidence favoring the use of DES over bare metal stents in diabetic patients with coronary artery disease. We also found that the current state of knowledge is that the everolimus eluting stents have better safety and efficacy than paclitaxel eluting stents in diabetic patients and hence should be the preferred choice. New revascularization strategies including bio-absorbable scaffolds, polymer free stents, and bio-degradable polymers are being studied in diabetic patients with encouraging results.

Drug-coated balloons for the treatment of in-stent restenosis in diabetic patients: A review of currently available scientific data

After the introduction of drug eluting stent (DES) the rate of in-stent restenosis (ISR) has decreased if compared to the BMS era; however, treatment of patients with ISR remained a major issue for the interventional cardiologist. DES has been largely used with good results also as second layer for the treatment of ISR, but the overall percentage of patients suffering from restenosis still remains high, especially in some subgroups of patients as ones with diabetes mellitus (DM). In this clinical scenario, drug coated balloon (DCB) has been gaining an important role for the treatment of ISR. In fact, it allows to release an antiproliferative drug, namely paclitaxel, without the addition of a second metallic strut, which can lead to a persistent inflammatory stimulus and further narrow the vessel. This could be an advantage in patients with an already increased systemic inflammatory burden and stiffer vessels as those with DM. Despite differences in terms of efficacy and safety between DES and DCB have already been evaluated in different clinical trials, just few of these focused on diabetic patients. The aim of this paper is to review the available data for treatment of ISR both with DES, DCB, and a comparison between these two devices, in patients affected by DM. © 2017 Wiley Periodicals, Inc.

Stent thrombosis and adverse cardiovascular outcomes observed between six months and five years with sirolimus-eluting stents and other drug-eluting stents in patients with Type 2 diabetes mellitus complicated by coronary artery disease: A systematic review and meta-analysis

This study aimed to compare 6 months to 5 years stent thrombosis (ST) and adverse cardiovascular outcomes associated with sirolimus-eluting stents (SES) and other drug-eluting stents (DES) in patients with type 2 diabetes mellitus (T2DM).Electronic databases were searched for studies comparing SES with other DES in patients with T2DM. Total ST, definite ST, probable ST, and other adverse cardiovascular outcomes reported between 6 months and 5 years were considered as the clinical end points in this study. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for categorical variables and the pooled analyses were performed with RevMan 5.3 software.Twenty-nine studies involving a total number of 25,729 patients with diabetes were included in this meta-analysis. SES were not associated with significantly higher total, definite, and probable STs with OR: 0.95, 95% CI: 0.77-1.17, P = 0.62; OR: 0.94, 95% CI: 0.65-1.37, P = 0.76; and OR: 1.05, 95% CI: 0.77-1.45, P = 0.74, respectively. SES were also noninferior to the other non-sirolimus eluting drug eluting stents (non-SE DES) in terms of all-cause mortality, cardiac death, myocardial infarction, and stroke with OR: 0.92, 95% CI: 0.82-1.03, P = 0.16; OR: 1.09, 95% CI: 0.88-1.35, P = 0.44; OR: 0.92, 95% CI: 0.80-1.06, P = 0.26; and OR: 0.79, 95% CI: 0.49-1.28, P = 0.43, respectively. Target vessel revascularization, target lesion revascularization, and major adverse cardiac events were also similarly reported between SES and non-SE DES with OR: 1.04, 95% CI: 0.83-1.31, P = 0.72; OR: 1.25, 95% CI: 0.95-1.64, P = 0.11; and OR: 1.06, 95% CI: 0.90-1.25, P = 0.49, respectively.During this particular follow-up period, SES were not associated with any increase in ST among these patients with T2DM. Mortality and other adverse cardiovascular outcomes were also not significantly different between these 2 groups. Hence, SES should be considered neither superior nor inferior to other DES. They are expected to be equally effective and safe to use in patients with T2DM.

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.

Drug-eluting stents and acute myocardial infarction: A lethal combination or friends?

Primary percutaneous coronary intervention is the preferred reperfusion strategy for patients presenting with ST-segment elevation myocardial infarction (STEMI). First generation drug-eluting stents (DES), (sirolimus drug-eluting stents and paclitaxel drug-eluting stents), reduce the risk of restenosis and target vessel revascularization compared to bare metal stents. However, stent thrombosis emerged as a major safety concern with first generation DES. In response to these safety issues, second generation DES were developed with different drugs, improved stent platforms and more biocompatible durable or bioabsorbable polymeric coating. This article presents an overview of safety and efficacy of the first and second generation DES in STEMI.

Intimal hyperplasia and vascular remodeling after everolimus-eluting and sirolimus-eluting stent implantation in diabetic patients: the randomized Diabetes and Drug-Eluting Stent (DiabeDES) IV Intravascular Ultrasound trial

OBJECTIVE

To evaluate the effects of the everolimus-eluting Xience™/Promus™ stent (EES) and the sirolimus-eluting Cypher™ stent (SES) on intimal hyperplasia (IH) in diabetic patients.

BACKGROUND

Patients with diabetes mellitus have increased risk of in-stent restenosis after coronary stent implantation due to intimal hyperplasia (IH).

METHODS

In a sub study of the Randomized Comparison of Everolimus-Eluting and Sirolimus-Eluting Stents in Patients Treated with Percutaneous Coronary Intervention (SORT OUT IV trial), serial intravascular ultrasound (IVUS) 10-month follow-up data were available in 88 patients, including 48 EES and 40 SES treated patients. IVUS endpoints included IH volume, in-stent % volume obstruction and changes in external elastic membrane (EEM) volume.

RESULTS

Compared with the SES group, IH volume was increased in the EES group [median (interquartile range): 2.8 mm(3) (0.0-12.6) vs. 0.0 mm(3) (0.0-1.1), P = 0.001]. In-stent % volume obstruction was increased in EES compared to SES [median (interquartile range): 1.6% (0.0-8.2) vs. 0.0% (0.0-1.0), P = 0.001]. Peri-stent external elastic membrane (EEM) volume: (post procedure vs. follow-up EES [300 mm(3) (219-491) vs. 307 mm(3) (223-482), P = 0.73] and SES [316 mm(3) (235-399) vs. 323 mm(3) (246-404), P = 0.05]) and peri-stent plaque volume: EES [163 mm(3) (103-273) vs. 184 mm(3) (115-291), P = 0.18] and SES [186 mm(3) (139-248) vs. 175 mm(3) (153-243), P = 0.26]) were unchanged in both groups. In the proximal reference segment a significant increase in plaque area was seen in the EES group only, without vascular remodeling.

CONCLUSION

In diabetic patients, EES stent implantation was associated with increased IH volume obstruction without involvement of vascular remodeling.

Clinical impact of second-generation everolimus-eluting stent compared with first-generation drug-eluting stents in diabetes mellitus patients: insights from a nationwide coronary intervention register

OBJECTIVES

This study sought to study the second-generation everolimus-eluting stent (EES) as compared with first-generation sirolimus-eluting (SES) and paclitaxel-eluting stents (PES) in diabetes mellitus (DM) patients.

BACKGROUND

There are limited data available comparing clinical outcomes in this setting with EES and SES, whereas studies comparing EES with PES are not powered for low-frequency endpoints.

METHODS

All DM patients treated with EES, PES, or SES from January 18, 2007, to July 29, 2011, from the SCAAR (Swedish Coronary Angiography and Angioplasty Registery) were included. The EES was compared with SES or PES for the primary composite endpoint of clinically driven detected restenosis, definite stent thrombosis (ST), and all-cause mortality.

RESULTS

In 4,751 percutaneous coronary intervention-treated DM patients, 8,134 stents were implanted (EES = 3,928, PES = 2,836, SES = 1,370). The EES was associated with significantly lower event rates compared with SES (SES vs. EES hazard ratio [HR]: 1.99; 95% confidence interval (CI): 1.19 to 3.08). The same was observed when compared with PES (PES vs. EES HR: 1.33; 95% CI: 0.93 to 1.91) but did not reach statistical significance. These results were mainly driven by lower incidence of ST (SES vs. EES HR: 2.87; 95% CI: 1.08 to 7.61; PES vs. EES HR: 1.74, 95% CI: 0.82 to 3.71) and mortality (SES vs. EES HR: 2.02; 95% CI: 1.03 to 3.98; PES vs. EES HR: 1.69; 95% CI: 1.06 to 2.72). No significant differences in restenosis rates were observed between EES and SES or PES (SES vs. EES HR: 1.26; 95% CI: 0.77 to 2.08; PES vs. EES HR: 1.05; 95% CI: 0.71 to 1.55).

CONCLUSIONS

In all-comer DM patients the use of EES was associated with improved outcomes compared with SES and PES mainly driven by lower rates of ST and mortality. These results suggest better safety rather than efficacy with EES when compared with SES or PES.

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.

The impact of preprocedural hemoglobin A1c on the efficacy of sirolimus-eluting and paclitaxel-eluting stents

Several reports have shown contrary results regarding the efficacy of sirolimus-eluting stents (SES) and paclitaxel-eluting stents (PES) in diabetic patients. The association between hemoglobin A1c (A1c) before coronary intervention and the midterm clinical outcomes of patients treated with these stents is unclear. The enrolled population was 415 patients with diabetes or impaired glucose tolerance (IGT) who underwent follow-up angiography after being implanted with a SES (n = 282) or PES (n = 133). The enrolled population was classified into the optimal glycemic control group (n = 213) and suboptimal glycemic control group (n = 202), and the predictors of restenosis were examined in each group. In the optimal glycemic control group, the use of PES was an independent predictor of restenosis [odds ratio (OR) 9.98, 95% confidence interval (CI) 3.08-38.9, p < 0.0001]; on the other hand, the use of SES was a positive independent predictor of restenosis prevention (OR 0.10, 95% CI 0.03-0.32, p < 0.0001). In the suboptimal glycemic control group, neither stent was predictive of restenosis. In a subanalysis, preprocedural A1c (≥7.0%) was found to be an independent predictor of restenosis in the SES group (OR 3.61, 95% CI 1.14-12.8, p = 0.03), but not the PES group. Postprocedural A1c (≥7.0%) was not an independent predictor of restenosis in either stent group. This study showed that the superiority of SES compared to PES was attenuated in the suboptimal glycemic control group. Preprocedural A1c (≥7.0%) was found to be an independent predictor of restenosis in the SES group, but not in the PES group.

Differences in drug-eluting stents used in coronary artery disease

The introduction of drug-eluting stents (DES) has improved the efficacy of percutaneous coronary intervention by addressing the issue of neointimal proliferation, a pathology contributing to restenosis. First-generation stents eluting sirolimus or paclitaxel were joined by second-generation stents, such as the everolimus- and the zotarolimus-eluting stents, promising increased safety and efficacy. As a result, there is a plethora of drug-eluting stents available, with differences in the stent platform, the polymer coating and the eluted drug, which translate into differences in biological markers of efficacy, such as late loss. However, it remains controversial whether these discrepancies have an impact on clinical markers of safety and efficacy, or if the improved efficacy of DES is a class effect. This article reviews the differences between DES by looking into the biological differences and into trials and registries of DES.

A meta-analysis of specifically designed randomized trials of sirolimus-eluting versus paclitaxel-eluting stents in diabetic patients with coronary artery disease

BACKGROUND

There is an ongoing debate on the optimal drug-eluting stent (DES) in diabetic patients with coronary artery disease. We addressed this issue by making a synthesis of the available evidence on the relative long-term efficacy and safety of sirolimus-eluting stent (SES) and paclitaxel-eluting stent (PES) in these patients.

METHODS

Individual patient data were analyzed from 6 randomized trials specifically designed to compare SES with PES in diabetic patients. In total, 1183 patients were followed up for a median of 3.9 years (25th, 75th percentiles 3.4-4.5 years). The primary efficacy end point was target lesion revascularization (TLR). The composite of death and myocardial infarction (MI) was the primary safety end point. Stent thrombosis was a secondary end point. Overall hazard ratios (HRs) with 95% CIs were calculated as summary estimates.

RESULTS

No significant heterogeneity was seen across the 6 randomized trials for all analyzed events. Sirolimus-eluting stent was associated with a significant reduction in the risk of TLR (HR 0.65 [0.47-0.91], P = .01). No significant differences were observed regarding the risk of death or MI (HR 1.04 [0.74-1.45], P = .83) and stent thrombosis (HR 1.00 [0.31-3.30], P = .67). Mortality was also not affected by the type of DES (HR 0.95 [0.65-1.39], P = .79).

CONCLUSIONS

In diabetic patients with coronary artery disease, SES leads to a sustained reduction in the risk of TLR compared with PES. Both these DES types are, however, comparable with respect to the risk of stent thrombosis, MI, or death over long-term follow-up.

Drug-eluting coronary stents - focus on improved patient outcomes

The development of stent has been a major advance in the treatment of obstructive coronary artery disease since the introduction of balloon angioplasty. Subsequently, neointimal hyperplasia within the stent leading to in-stent restenosis emerged as a major obstacle in long-term success of percutaneous coronary intervention. Recent introduction of drug-eluting stents is a major breakthrough to tackle this problem. This review article summarizes stent technology, reviews progress of drug-eluting stents and discusses quality of life, patient satisfaction, and acceptability of percutaneous coronary intervention.

Randomized comparison of a polymer-free sirolimus-eluting stent versus a polymer-based paclitaxel-eluting stent in patients with diabetes mellitus: the LIPSIA Yukon trial

OBJECTIVES

The objective of the study was to assess noninferiority of the polymer-free sirolimus-eluting Yukon Choice stent (Translumina GmbH, Hechingen, Germany) compared with the polymer-based Taxus Liberté stent (Boston Scientific, Natick, Massachusetts) with regard to the primary endpoint, in-stent late lumen loss, at 9 months in patients with diabetes mellitus.

BACKGROUND

The Yukon Choice stent has been evaluated in several randomized controlled trials before, albeit to date, there has been no trial that exclusively enrolled patients with diabetes mellitus.

METHODS

Patients with diabetes mellitus undergoing percutaneous coronary intervention for clinically significant de novo coronary artery stenosis were randomized 1:1 to receive either the polymer-free sirolimus-eluting Yukon Choice stent or the polymer-based paclitaxel-eluting Taxus Liberté stent.

RESULTS

A total of 240 patients were randomized. Quantitative coronary angiography was available for 79% of patients. Mean in-stent late lumen loss was 0.63 ± 0.62 mm for the Yukon Choice stent and 0.45 ± 0.60 mm for the Taxus Liberté stent. Based on the pre-specified margin, the Yukon Choice stent failed to show noninferiority for the primary endpoint. During follow-up, there were no significant differences between groups regarding death, myocardial infarction, stent thrombosis, target lesion revascularization, target vessel revascularization, or nontarget vessel revascularization.

CONCLUSIONS

Compared with the Taxus Liberté stent, the polymer-free sirolimus-eluting Yukon Choice stent failed to show noninferiority with regard to the primary endpoint, in-stent late lumen loss, in patients with diabetes mellitus after 9-month follow-up. Both stents showed comparable clinical efficacy and safety. (Yukon Choice Versus Taxus Liberté in Diabetes Mellitus; NCT00368953).

Randomized comparison of everolimus-eluting stent versus sirolimus-eluting stent implantation for de novo coronary artery disease in patients with diabetes mellitus (ESSENCE-DIABETES): results from the ESSENCE-DIABETES trial

BACKGROUND

Drug-eluting stents significantly improved angiographic and clinical outcomes compared with bare metal stents in diabetic patients. However, a comparison of everolimus-eluting stents and sirolimus-eluting stents in diabetic patients has not been evaluated. Therefore we compared effectiveness of everolimus-eluting stents and sirolimus-eluting stents in patients with diabetes mellitus.

METHODS AND RESULTS

This prospective, multicenter, randomized study compared everolimus-eluting stent (n=149) and sirolimus-eluting stent (n=151) implantation in diabetic patients. The primary end point was noninferiority of angiographic in-segment late loss at 8 months. Clinical events were also monitored for at least 12 months. Everolimus-eluting stents were noninferior to sirolimus-eluting stents for 8-month in-segment late loss (0.23 ± 0.27 versus 0.37 ± 0.52 mm; difference, -0.13 mm; 95% confidence interval, -0.25 to -0.02; upper 1-sided 95% confidence interval, -0.04; P<0.001 for noninferiority), with reductions in in-stent restenosis (0% versus 4.7%; P=0.029) and in-segment restenosis (0.9% versus 6.5%; P=0.035). However, in-stent late loss (0.11 ± 0.26 versus 0.20 ± 0.49 mm; P=0.114) was not statistically different between the 2 groups. At 12 months, ischemia-driven target lesion revascularization (0.7% versus 2.6%; P=0.317), death (1.3% versus 3.3%; P=0.448), and myocardial infarction (0% versus 1.3%; P=0.498) were not statistically different between the 2 groups. Major adverse cardiac events, including death, myocardial infarction, and ischemia-driven target lesion revascularization (2.0% versus 5.3%; P=0.218), were also not statistically different between the 2 groups.

CONCLUSION

Everolimus-eluting stents were noninferior to sirolimus-eluting stents in reducing in-segment late loss and reduced angiographic restenosis at 8 months in patients with diabetes mellitus and coronary artery disease.

Hybrid coronary revascularization: a review

The long-term benefits of a left internal mammary artery bypass graft compared to the left anterior descending artery have been well described. The use of drug-eluting stents has minimized the morbidity of revascularization. Hybrid coronary revascularization is the planned use of minimally invasive surgical techniques for left internal mammary artery-left anterior descending artery grafting and the use of percutaneous coronary intervention for nonleft anterior descending coronary artery target revascularization. The optimal timing and order of revascularization in hybrid coronary revascularization remains unclear.

Cost analysis of four major drug-eluting stents in diabetic populations

AIM

To use an indirect comparisons approach and conduct a cost analysis comparing four drug-eluting stents (DES) from a United States (US) payer (i.e., fixed-fee reimbursement) perspective.

METHODS AND RESULTS

Studies were chosen that randomised two or more DES in diabetic patients. A one-year target lesion revascularisation (TLR) risk for Taxus was first derived. Risk Ratios (RRs) for each DES versus Taxus were calculated through meta-analyses. The RRs were multiplied by the average TLR risk for Taxus to estimate DES TLR risks. Estimates were added to a budget-impact model, along with utilisation and reimbursement rates for diagnosis-related groups. Budgets were calculated, assuming 100% stent use and 200,000 diabetic beneficiaries. One-year TLR risks were estimated to be 3.2%, 7.1%, 6.9% and 7.9% for Cypher, Endeavor, Taxus and Xience respectively. By substituting Cypher for DES with higher TLR, results predicted annual cost-savings greater than $146 million per population ($ 733 per patient). Results were comparable when assuming no difference in TLR risk between Endeavor, Taxus and Xience.

CONCLUSIONS

When outcomes from trials of diabetic populations are analysed and used in a budget-impact model from a US payer perspective, the use of Cypher is associated with lower TLR rates, which translates into large potential cost savings.

Optical coherence tomographic analysis of in-stent neoatherosclerosis after drug-eluting stent implantation

BACKGROUND

We report findings from optical coherence tomography (OCT) of in-stent neoatherosclerosis as a cause of drug-eluting stent (DES) failure.

METHODS AND RESULTS

Optical coherence tomography and grayscale and virtual histology intravascular ultrasound were performed in 50 patients (30 stable, 20 unstable angina) with 50 DES in-stent restenosis lesions and intimal hyperplasia >50% of stent area. Median follow-up time was 32.2 months. Overall, 26 lesions (52%) had at least 1 OCT-defined in-stent thin-cap fibroatheroma (TCFA)-containing neointima and 29 (58%) had at least 1 in-stent neointimal rupture. Patients presenting with unstable angina showed a thinner fibrous cap (55 μm [interquartile range 42 to 105 μm] versus 100 μm [interquartile range 60 to 205 μm], P=0.006) and higher incidence of OCT-defined TCFA-containing neointima (75% versus 37%, P=0.008), intimal rupture (75% versus 47%, P=0.044), thrombi (80% versus 43%, P=0.010), and red thrombi (30% versus 3%, P=0.012) than stable patients. Fibrous cap thickness negatively correlated with follow-up time (r=-0.318, P=0.024). Compared with DES <20 months after implantation (the best cut-off to predict TCFA-containing neointima), DES ≥20 months after implantation had a higher incidence of TCFA-containing neointima (69% versus 33%, P=0.012) and red thrombi (27% versus 0%, P=0.007). Patients with unstable (versus stable) angina had an increasing number of unstable OCT findings including TCFA-containing neointima, neointima rupture, and thrombus (P=0.027). The rate of agreement between grayscale intravascular ultrasound and OCT for detecting intimal rupture was 50% and for detecting thrombus was 44%. The agreement between virtual histology intravascular ultrasound and OCT for identifying TCFA-containing neointima was 78%.

CONCLUSIONS

In-stent neoatherosclerosis may be an important mechanism of DES failure, especially late after implantation.

Efficacy and safety of abciximab in diabetic patients who underwent percutaneous coronary intervention with thienopyridines loading: a meta-analysis

BACKGROUND

It has been controversial whether abciximab offered additional benefits for diabetic patients who underwent percutaneous coronary intervention (PCI) with thienopyridines loading.

METHODS

MEDLINE, EMBASE, the Cochrane library clinical trials registry, ISI Science Citation Index, ISI Web of Knowledge and China National Knowledge Infrastructure (CNKI) were searched, supplemented with manual-screening for relevant publications. Quantitative meta-analyses were performed to assess differences between abciximab groups and controls with respect to post-PCI risk of major cardiac events (MACEs), angiographic restenosis and bleeding complications.

RESULTS

9 trials were identified, involving 2,607 diabetic patients receiving PCI for coronary artery diseases. Among those patients who underwent elective PCI or primary PCI, pooling results showed that abciximab did not significantly reduce risks of MACEs (for elective-PCI patients: RR(1-month): 0.93, 95% CI: 0.60-1.44; RR(1-year): 0.95, 95% CI: 0.81-1.11; for primary-PCI patients: RR(1-month): 1.05, 95% CI: 0.70-1.57; RR(1-year): 0.98, 95% CI: 0.80-1.21), nor all-cause mortality, re-infarction and angiographic restenosis in either group. The only beneficial effect by abciximab appeared to be a decrease 1-year TLR (target lesion revascularization) risk in elective-PCI patients (RR1-year: 0.83, 95% CI: 0.70-0.99). Moreover, occurrence of minor bleeding complications increased in elective-PCI patients treated with abciximab (RR: 2.94, 95% CI: 1.68-5.13, P<0.001), whereas major bleedings rate was similar (RR: 0.83, 95% CI: 0.27-2.57).

CONCLUSIONS

Concomitant dosing of abciximab and thienopyridines provides no additional benefit among diabetic patients who underwent PCI; this conclusion, though, needs further confirmation in larger studies.

Mechanisms of In-Stent Restenosis After Drug-Eluting Stent Implantation

Background—

We used intravascular ultrasound (IVUS) to (1) clarify the mechanisms of luminal loss after drug-eluting stent (DES) implantation and (2) classify morphological patterns of in-stent restenosis (ISR).

Methods and Results—

On the basis of IVUS-identified luminal narrowing (in-stent minimum lumen area <4 mm 2 ), IVUS-defined ISR was classified as focal (luminal narrowing ≤10 mm in length), multifocal (≥1 focal lesions), and diffuse (luminal narrowing >10 mm in length) with or without stent edge involvement. Significant intimal hyperplasia (IH) was defined as IH area >50% of stent. Overall, 76 lesions had IVUS-defined ISR; 32 (42%) had stent underexpansion (minimal stent area <5 mm 2 ); and 71 (93%) had IH area >50% of stent. Total stent length negatively correlated with minimal stent area ( r =−0.613, P <0.001) as well as with stent area at the minimum lumen site ( r =−0.436, P <0.001) but not with minimum lumen area ( r =−0.084, P =0.472). Underexpansion was present at the minimum lumen site in 15 of 43 (35%) lesions with stent length >28 mm, even though there was significant IH in 34 (79%) lesions; conversely, in 32 of 33 (97%) lesions with stent length ≤28 mm, the minimum lumen site was not associated with stent underexpansion but significant IH. IVUS-defined focal ISR was most common (47%). Compared with focal ISR, normalized vessel, stent, lumen, and plaque volumes were smaller in diffuse and multifocal than focal ISR, with no difference in IH extent.

Conclusions—

In most DES restenosis, IH was the dominant mechanism of ISR. Nevertheless, underexpansion associated with longer stent length remained an important preventable mechanism of ISR.

Tissue characterization of in-stent neointima using intravascular ultrasound radiofrequency data analysis

Using virtual histology and intravascular ultrasound (VH-IVUS), tissue characterization of restenotic in-stent neointima after drug-eluting stent (DES) and bare metal stent (BMS) implantation was assessed. VH-IVUS was performed in 117 lesions (70 treated with DESs and 47 treated with BMSs) with angiographic in-stent restenosis and intimal hyperplasia (IH) > 50% of the stent area. The region of interest was placed between the luminal border and the inner border of the struts and tissue composition was reported as percentages of IH area (percent fibrous, percent fibrofatty, percent necrotic core, percent dense calcium) at the 2 sites of maximal percent IH and maximal percent necrotic core. Mean follow-up times between stent implantation and VH-IVUS study were 43.5 ± 33.8 months for BMS-treated lesions and 11.1 ± 7.8 months for DES-treated lesions (p < 0.001). The 2 groups had greater percent necrotic core and percent dense calcium at maximal percent IH and maximal percent necrotic core sites, especially in stents that had been implanted for longer periods. In conclusion, this VH-IVUS analysis showed that BMS- and DES-treated lesions develop in-stent necrotic core and dense calcium, suggesting the development of in-stent neoatherosclerosis.

Major adverse cardiac events in patients with hepatitis C infection treated with bare-metal versus drug-eluting stents

BACKGROUND

There are no data comparing the long-term outcome of bare-metal stents (BMS) vs drug-eluting stents (DES) in patients with hepatitis C virus (HCV) infection.

HYPOTHESIS

In patients with HCV infection, the rate of major adverse cardiac events (MACE) would be less, and the mortality rates similar, in patients treated with DES than in patients treated with BMS.

METHODS

The incidence of major adverse cardiac events (MACE) during long-term follow-up, including death, myocardial infarction, and target-vessel revascularization, was investigated in HCV-infected patients who also underwent percutaneous coronary intervention with bare-metal or drug-eluting stents.

RESULTS

Of 78 patients studied, BMS were placed in 41 patients and DES stents in 37 patients. Stepwise Cox regression analyses were performed to identify significant independent risk factors for MACE. At 42 +/- 11-month follow-up, MACE occurred in 9 of 41 patients (22%) in the BMS group (mean age 63 +/- 11 years, 66% men) vs in 7 of 37 patients (19%) in the DES group (mean age 61 +/- 9 years, 65% men). There was no significant difference in MACE in the BMS group vs the DES group. This persisted even after controlling for length of the stent, complexity of lesion, and other comorbidities. All-cause mortality was not significantly different in the BMS group vs the DES group (7% vs 5%).

CONCLUSIONS

At long-term follow-up of HCV-infected patients with stable liver function, the rates of MACE and of all-cause mortality were similar in the BMS and DES groups.

Three-year outcomes following sirolimus- versus paclitaxel-eluting stent implantation in an unselected population with coronary artery disease (from the REWARDS Registry)

The Registry Experience at the Washington Hospital Center with Drug-Eluting Stents (REWARDS) study includes unselected patients with coronary artery disease treated with sirolimus-eluting stents (SESs; n = 2,392) or paclitaxel-eluting stents (PES; n = 1,119). This study aimed to examine the long-term safety profile of the 2 stents in a "real-world" population, especially in relation to stent thrombosis, and to compare differences in the diabetic cohort. Patients were followed for 3 years with regard to major adverse cardiac events (MACEs), including death, Q-wave myocardial infarction, and target lesion revascularization. Rates of stent thrombosis were also studied. Baseline characteristics were similar between stents. Although MACE rates at 3 years were similar (SES 28.1% vs PES 28.9%, p = 0.62), there was a significant difference in unadjusted rates of target lesion revascularization (SES 15.6% vs PES 12.6%, p = 0.03), death (SES 15.7% vs PES 19.0%, p = 0.02), and Q-wave myocardial infarction (SES 0.8% vs PES 2.1%, p = 0.003). After multivariable Cox regression to adjust for confounders, there was no significant difference in overall MACEs. Incidence of stent thrombosis was higher in the SES group (SES 2.2% vs PES 1.6%, p = 0.22), but this was not statistically significant (hazard ratio 1.6, 95% confidence interval 0.8 to 2.9, p = 0.17). Overall, diabetics had a higher MACE rate, but there was no difference between insulin- and noninsulin-dependent diabetics. In conclusion, at 3 years, PES and SES achieved similar results in MACEs and stent thrombosis. This should foster confidence that SES or PES can be compared to second-generation drug-eluting stents without concerns for safety or efficacy.

Late and very late drug-eluting stent malapposition: serial 2-year quantitative IVUS analysis

BACKGROUND

The long-term natural history of acquired malapposition continues to be the subject of debate.

METHODS AND RESULTS

Using volumetric intravascular ultrasound analyses, we evaluated serial (poststenting, 6-month, and 2-year follow-up) changes in drug-eluting stent-treated vascular segments with acquired malapposition. External elastic membrane, stent, lumen, malapposition, and peristent plaque+media (P+M=external elastic membrane -stent- malapposition) areas were measured; and volumes were calculated and divided by stent length (normalized volume). Among 250 lesions in which complete serial intravascular ultrasound data were available, stent malapposition was identified in 19 lesions (7.6%) at 6 months, and an additional 13 malapposition lesions were newly detected at 2 years (5.2%). Because no malapposition sites resolved, the malapposition rate at 2 years was 12.8%. Malapposition areas and volumes were correlated to the increases in external elastic membrane (positive remodeling) throughout the study period, from immediately after stenting to 6 months and from 6 months to 2 years, both in the group that developed malapposition at 6 months and in the group that developed malapposition at 2 years. Clinical follow-up beyond the 2 year intravascular ultrasound study was done in all patients. Overall, there were 2 cardiac deaths and 1 noncardiac death. Two patients presented with acute myocardial infarction associated with very late stent thrombosis (1 definite stent thrombosis, 1 probable stent thrombosis). Three patients underwent repeat revascularization owing to in-stent restenosis developed after the 2-year follow-up.

CONCLUSIONS

Expansive vascular remodeling may play a role in the development and dynamic progression of acquired drug-eluting stent malapposition, not only during the first 6 months after implantation but thereafter.

Current state of integrated "hybrid" coronary revascularization

The long-term benefits of a left internal mammary artery bypass graft to the left anterior descending artery (LAD) have been well described. As the patient population with multivessel coronary artery disease has grown older with greater comorbidities, less invasive approaches to revascularization have been explored. The use of drug-eluting stents has minimized the morbidity of revascularization but has failed to match the durability of coronary artery bypass grafting (CABG). Hybrid coronary revascularization (HCR) is the planned use of minimally invasive surgical techniques for left internal mammary artery-LAD grafting and the use of percutaneous coronary interventions (PCI) for non-LAD target revascularization. The optimal timing and order of revascularization in HCR remains unclear. Novel operating suites with surgical and fluoroscopic capabilities have begun to support the performance of simultaneous minimally invasive CABG and PCI. The role of HCR compared to both PCI and conventional CABG awaits the results of ongoing randomized clinical trials.

Long-term vascular changes after drug-eluting stent implantation assessed by serial volumetric intravascular ultrasound analysis

Using serial volumetric intravascular ultrasonography, we evaluated the predictors of late intimal hyperplasia (IH) increases after drug-eluting stent implantation. All eligible patients who underwent 6-month angiography without visual restenosis were requested to undergo a 2-year follow-up examination. Complete serial (after stenting and early [6-month], and late [2-year] follow-up) angiographic and intravascular ultrasound data were available for 135 patients with 143 lesions: 99 sirolimus-eluting stents and 44 paclitaxel-eluting stents. The external elastic membrane, stent, lumen, and peri-stent plaque volumes (external elastic membrane minus stent) were normalized by stent length. The percentage of IH volume was calculated as IH volume/stent volume x 100. The early reduction in the minimum lumen area was greater than the late reduction in the minimum lumen area (-0.8 +/- 0.8 vs -0.2 +/- 0.5 mm(2), p <0.001). A progressive increase occurred in the percentage of IH volume: 8.1 +/- 7.1% from baseline to 6 months and 2.4 +/- 3.9% from 6 months to 2 years (p <0.001, between the early and late increases in the percentage of IH). The use of paclitaxel-eluting stents was the only independent predictor for the percentage of IH volume at 6 months (beta = 0.419, p <0.001). The use of paclitaxel-eluting stents (beta = 0.365, p <0.001, 95% confidence interval 3.7 to 9.7) and the post-stenting normalized plaque and media volume (beta = 0.195, p = 0.020, 95% confidence interval 0.1 to 1.6) were the only independent predictors for the percentage of IH volume at 2 years. However, when the percentage of IH at 6 months was forced into the model, the percentage of IH at 6 months and the post-stenting normalized plaque and media volume, not paclitaxel-eluting stent use, predicted the 2-year percentage of IH. In conclusion, although IH continued to increase beyond 6 months, the growth rate of intima and luminal loss attenuated with time.