Comprehensive meta-analysis on drug-eluting stents versus bare-metal stents during extended follow-up

Stent Thrombosis After Percutaneous Coronary Intervention: From Bare-Metal to the Last Generation of Drug-Eluting Stents

Since their introduction in clinical practice in 1986, different types of coronary stents have been developed and become available for the treatment of coronary artery disease. Stent thrombosis (ST) is an uncommon but harmful complication after percutaneous coronary implantation, with a high occurrence of acute myocardial infarction and risk of mortality. Among several procedural and clinical predictors, the type of coronary stent is a strong determinant of ST. This article reviews the available evidence on the most used coronary stent types in the modern era and the related risk of ST.

Successful implantation of a novel polymer-free everolimus-eluting stent using nitrogen-doped titanium dioxide film with good patency on follow-up angiography: A case report

RATIONALE

Despite technological advances in interventional cardiology during the last decades, many concerns remain regarding the narrowing and occlusion of the in-stent area. Particularly, polymer materials pose several problems, including chronic arterial inflammation, impaired arterial healing, and stent thrombosis. To avoid these complications, we invented the TIGEREVOLUTION stent with a cobalt-chromium alloy-based stent platform deposited with N-TiO2 film, which has demonstrated good biocompatibility. As this stent is not coated with polymer, it is expected to have decreased risk of stent thrombosis.

PATIENT CONCERNS

A 62-year-old Korean man visited our department because of angina. We commenced coronary angiography (CAG).

DIAGNOSIS

CAG revealed critical stenosis in the mid-portion of the right coronary artery, with a minimum lumen area of 1.08mm2 on optical coherence tomography (OCT).

INTERVENTION

Percutaneous coronary intervention was performed with implantation of a novel 3.5 × 26-mm polymer-free everolimus-eluting stent using nitrogen-doped titanium dioxide film (TIGEREVOLUTION® stent). Post-percutaneous coronary intervention OCT showed good stent expansion and apposition, and the patient was discharged successfully and uneventfully.

OUTCOMES

Eight months later, follow-up coronary angiography demonstrated good stent patency with no definitive evidence of in-stent restenosis, with thin stent strut coverage demonstrated on OCT.

LESSONS

We report the first case of TIGEREVOLUTION stent implantation with follow-up OCT at 8 months.

A First-in-Man Clinical Evaluation of Sirolimus and Ascorbic Acid-Eluting Stent Systems: a Multicenter, Subject-Blinded, Randomized Study

This prospective, multi-center, randomized, comparative, and pivotal clinical study in patients with coronary artery occlusive disease was conducted to evaluate the safety and efficacy of D+Storm™ drug-eluting stent (DES), a sirolimus-eluting stent coated with polylactic acid and ascorbic acid. Our results showed that in-segment late lumen loss of D+Storm™ DES group was non-inferior to BioMatrix Flex™ DES group and the total procedural success rate of D+Storm™ DES group was 100%. In addition, the safety of the D+Storm™ DES group at 36 weeks was also demonstrated in this study.

Background and Objectives

This clinical trial was conducted to evaluate the safety and efficacy of D+Storm™ drug-eluting stent (DES) and BioMatrix Flex™ DES.

Methods

This study was a multicenter, subject-single-blind, randomized, and confirmed comparative clinical trial. According to the inclusion criteria, those diagnosed with stable angina, unstable angina, silent ischemia, or non-ST-segment myocardial infarction were selected among patients with coronary artery stenosis as subjects. Among the subjects with 50% stenosis on coronary angiography, the experiment was performed on those who had a lesion with reference vessel 2.5–4.0 mm in diameter and ≤40 mm in length. The primary endpoint was an in-segment late loss and the secondary endpoints were in-stent late lumen loss, stent malapposition, the incidence of mortality, myocardial infarction, reoperation, and stent thrombosis at 36 weeks.

Results

57 patients in the D+Storm™ DES group and 55 patients in the BioMatrix Flex™ DES group were enrolled in the study. Fifty-seven patients in the D+Storm™ DES group and Fifty-five patients in the BioMatrix Flex™ DES group were enrolled in the study. An average of in-segment late lumen loss was 0.08±0.13 mm in the D+Storm™ DES group and 0.14±0.32 mm in the BioMatrix Flex™ DES group with no significant difference between the 2 groups (p=0.879). In addition, there was no significant difference in adverse events between D+Storm™ DES and BioMatrix Flex™ DES.

Conclusions

This study demonstrated the clinical effectiveness and safety of D+Storm™ DES implantation in patients with coronary artery disease over a 36-week follow-up period.

Stent Thrombosis After Percutaneous Coronary Intervention: From Bare-Metal to the Last Generation of Drug-Eluting Stents

Since their introduction in clinical practice in 1986, different types of coronary stents have been developed and become available for the treatment of coronary artery disease. Stent thrombosis (ST) is an uncommon but harmful complication after percutaneous coronary implantation, with a high occurrence of acute myocardial infarction and risk of mortality. Among several procedural and clinical predictors, the type of coronary stent is a strong determinant of ST. This article reviews the available evidence on the most used coronary stent types in the modern era and the related risk of ST.

Palliative treatment of coronary "atherosclerotic cancer" by drug-eluting or bare-metal stents: From oculo-stenotic reflex period to age of precision medicine

Medications and treatments are said to have a palliative effect if they relieve symptoms without having a curative effect on the underlying disease such as atherosclerosis or cancer. Some authors speculated that atherosclerotic coronary artery disease (CAD) could be considered a "cancer of the coronary arterial wall". Although the percutaneous coronary intervention (PCI) has proven to be effective in decreasing mortality rates among patients with acute coronary syndromes, the previous meta-analyses of PCI versus optimal medical therapy for stable CAD have not been able to demonstrate a reduction in major adverse cardiac outcomes. However, few cardiologists discussed the evidence-based benefits of angiogram and PCI for stable CAD, and some implicitly or explicitly overstated the benefits. Recently, the precision medicine is defined as an evidence-based approach that uses innovative tools and biological and data science to customize disease prevention, detection, and treatment, and improve the effectiveness and quality of patient care. Providing patients with accurate and complete information appears to be an effective way to combat the reliance on the oculostenotic reflex. The foundation of precision medicine is the ability to tailor therapy based upon the expected risks and benefits of treatment for each individual patient. As said by Doctor William Osler, "The good physician treats the disease; the great physician treats the patient who has the disease."

Drug-eluting stents versus bare-metal stents for acute coronary syndrome

BACKGROUND

Approximately 3.7 million people died from acute coronary syndrome worldwide in 2012. Acute coronary syndrome, also known as myocardial infarction or unstable angina pectoris, is caused by a sudden blockage of the blood supplied to the heart muscle. Percutaneous coronary intervention is often used for acute coronary syndrome, but previous systematic reviews on the effects of drug-eluting stents compared with bare-metal stents have shown conflicting results with regard to myocardial infarction; have not fully taken account of the risk of random and systematic errors; and have not included all relevant randomised clinical trials.

OBJECTIVES

To assess the benefits and harms of drug-eluting stents versus bare-metal stents in people with acute coronary syndrome.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, LILACS, SCI-EXPANDED, and BIOSIS from their inception to January 2017. We also searched two clinical trials registers, the European Medicines Agency and the US Food and Drug Administration databases, and pharmaceutical company websites. In addition, we searched the reference lists of review articles and relevant trials.

SELECTION CRITERIA

Randomised clinical trials assessing the effects of drug-eluting stents versus bare-metal stents for acute coronary syndrome. We included trials irrespective of publication type, status, date, or language.

DATA COLLECTION AND ANALYSIS

We followed our published protocol and the methodological recommendations of Cochrane. Two review authors independently extracted data. We assessed the risks of systematic error by bias domains. We conducted Trial Sequential Analyses to control the risks of random errors. Our primary outcomes were all-cause mortality, major cardiovascular events, serious adverse events, and quality of life. Our secondary outcomes were angina, cardiovascular mortality, and myocardial infarction. Our primary assessment time point was at maximum follow-up. We assessed the quality of the evidence by the GRADE approach.

MAIN RESULTS

We included 25 trials randomising a total of 12,503 participants. All trials were at high risk of bias, and the quality of evidence according to GRADE was low to very low. We included 22 trials where the participants presented with ST-elevation myocardial infarction, 1 trial where participants presented with non-ST-elevation myocardial infarction, and 2 trials where participants presented with a mix of acute coronary syndromes.Meta-analyses at maximum follow-up showed no evidence of a difference when comparing drug-eluting stents with bare-metal stents on the risk of all-cause mortality or major cardiovascular events. The absolute risk of death was 6.97% in the drug-eluting stents group compared with 7.74% in the bare-metal stents group based on the risk ratio (RR) of 0.90 (95% confidence interval (CI) 0.78 to 1.03, 11,250 participants, 21 trials/22 comparisons, low-quality evidence). The absolute risk of a major cardiovascular event was 6.36% in the drug-eluting stents group compared with 6.63% in the bare-metal stents group based on the RR of 0.96 (95% CI 0.83 to 1.11, 10,939 participants, 19 trials/20 comparisons, very low-quality evidence). The results of Trial Sequential Analysis showed that we did not have sufficient information to confirm or reject our anticipated risk ratio reduction of 10% on either all-cause mortality or major cardiovascular events at maximum follow-up.Meta-analyses at maximum follow-up showed evidence of a benefit when comparing drug-eluting stents with bare-metal stents on the risk of a serious adverse event. The absolute risk of a serious adverse event was 18.04% in the drug-eluting stents group compared with 23.01% in the bare-metal stents group based on the RR of 0.80 (95% CI 0.74 to 0.86, 11,724 participants, 22 trials/23 comparisons, low-quality evidence), and Trial Sequential Analysis confirmed this result. When assessing each specific type of adverse event included in the serious adverse event outcome separately, the majority of the events were target vessel revascularisation. When target vessel revascularisation was analysed separately, meta-analysis showed evidence of a benefit of drug-eluting stents, and Trial Sequential Analysis confirmed this result.Meta-analyses at maximum follow-up showed no evidence of a difference when comparing drug-eluting stents with bare-metal stents on the risk of cardiovascular mortality (RR 0.91, 95% CI 0.76 to 1.09, 9248 participants, 14 trials/15 comparisons, very low-quality evidence) or myocardial infarction (RR 0.98, 95% CI 0.82 to 1.18, 10,217 participants, 18 trials/19 comparisons, very low-quality evidence). The results of the Trial Sequential Analysis showed that we had insufficient information to confirm or reject our anticipated risk ratio reduction of 10% on cardiovascular mortality and myocardial infarction.No trials reported results on quality of life or angina.

AUTHORS' CONCLUSIONS

The current evidence suggests that drug-eluting stents may lead to fewer serious adverse events compared with bare-metal stents without increasing the risk of all-cause mortality or major cardiovascular events. However, our Trial Sequential Analysis showed that there currently was not enough information to assess a risk ratio reduction of 10% for all-cause mortality, major cardiovascular events, cardiovascular mortality, or myocardial infarction, and there were no data on quality of life or angina. The evidence in this review was of low to very low quality, and the true result may depart substantially from the results presented in this review.More randomised clinical trials with low risk of bias and low risks of random errors are needed if the benefits and harms of drug-eluting stents for acute coronary syndrome are to be assessed properly. More data are needed on the outcomes all-cause mortality, major cardiovascular events, quality of life, and angina to reduce the risk of random error.

Comparison of Bare-Metal Stent and Drug-Eluting Stent for the Treatment of Patients Undergoing Percutaneous Coronary Intervention for Unprotected Left Main Coronary Artery Disease - Long-Term Result from a Single Center Experience

BACKGROUND

Percutaneous coronary intervention (PCI) has become an alternative treatment for left main (LM) coronary artery disease. The aim of our study was to compare long-term clinical outcomes of patients undergoing unprotected LM PCI with bare-metal stent (BMS) or drug-eluting stent (DES) in a high-risk population.

METHODS AND RESULTS

We enrolled 223 consecutive patients with unprotected LM coronary artery disease undergoing PCI (mean age: 71.1 ± 11.2 years, 187 male), including 94 patients receiving BMS and 129 patients receiving DES. The patients receiving DES had a significantly higher SYNTAX score (p = 0.05). During the mean follow-up period of 2.5 years, there were 31 cardiovascular deaths (BMS: 21 cases, DES: 10 cases, p = 0.04 by log-rank test), 56 major adverse cardiovascular events (MACE, including cardiovascular death, non-fatal myocardial infarction (MI) and clinical-driven target lesion revascularization; BMS: 33 cases, DES: 23 cases, p = 0.03 by log-rank test) and 6 cases with definite/probable stent thrombosis (BMS: 5 cases, DES: 1 cases, p = 0.09). In multivariate Cox analysis, the use of DES was identified as an independent protective factor against cardiovascular death [hazard ratio (HR) = 0.34, 95% confidence interval (Cl) = 0.15-0.79, p = 0.01] and MACE (HR = 0.50, 95% CI = 0.28-0.88, p = 0.02). The clinical outcome analyses in propensity-score matched the cohort (87 matched pair of patients receiving BMS and DES) and yielded similar results.

CONCLUSIONS

In the general practice among a high-risk population undergoing unprotected LM PCI, the use of DES appeared to be beneficial in reducing the risk of long-term cardiovascular death and MACE.

KEY WORDS

Bare-mental stent; Drug-eluting stent; Left main coronary artery disease; Percutaneous coronary intervention.

Bioresorbable scaffold - A magic bullet for the treatment of coronary artery disease?

Today, drug-eluting metal stents are considered the gold standard for interventional treatment of coronary artery disease. While providing inhibition of neointimal hyperplasia, drug-eluting metal stents have many limitations such as the risk of late and very late stent thrombosis, restriction of vascular vasomotion and chronic local inflammatory reaction due to permanent implantation of a 'metallic cage', recognized as a foreign body. Bioresorbable scaffold stents (BRS) are a new solution, which is trying to overcome the limitation of the 'metallic cage'. This structure provides short-term scaffolding of the vessel and then disappears, leaving nothing behind. The purpose of this review is to present the theoretical rationale for the use of BRS and to outline the clinical outcomes associated with their use in terms of data obtained from RCTs, clinical trials, registries and real life use. We have also tried to answer all questions on this intervention based on available data, with a focus on ABSORB BVS (Abbott Vascular, Santa Clara, USA). We consider that this new technology can be the "magic bullet" to treat coronary artery disease.

Management of Complications

Percutaneous coronary intervention (PCI) has matured rapidly to tackle increasingly complex coronary disease. Operators must be aware of the incidence of the basic risks involved with coronary angiography and PCI to appropriately inform patients and obtain procedural consent. Even before a wire enters a coronary artery, specific risks, including vascular access complications, renal injury, allergic reaction, and radiation injury, are constantly present. With initiation of PCI, new risks to the coronary circulation arise. A fundamental knowledge of the presentation of these complications and expert ability to emergently manage them are of the utmost importance to the successful completion of PCI.

Treatment variation in stent choice in patients with stable or unstable coronary artery disease

AIM

Variations in treatment are the result of differences in demographic and clinical factors (e.g. anatomy), but physician and hospital factors may also contribute to treatment variation. The choice of treatment is considered important since it could lead to differences in long-term outcomes. This study explores the associations with stent choice: i.e. drug-eluting stent (DES) versus bare-metal stents (BMS) for Dutch patients diagnosed with stable or unstable coronary artery disease (CAD).

METHODS & RESULTS

Associations with treatment decisions were based on a prospective cohort of 692 patients with stable or unstable CAD. Of those patients, 442 patients were treated with BMS or DES. Multiple logistic regression analyses were performed to identify variables associated with stent choice. Bivariate analyses showed that NYHA class, number of diseased vessels, previous percutaneous coronary intervention, smoking, diabetes, and the treating hospital were associated with stent type. After correcting for other associations the treating hospital remained significantly associated with stent type in the stable CAD population.

CONCLUSIONS

This study showed that several factors were associated with stent choice. While patients generally appear to receive the most optimal stent given their clinical characteristics, stent choice seems partially determined by the treating hospital, which may lead to differences in long-term outcomes.

STENTING STRATEGY AND FOLLOW-UP RESULTS OF MULTI-CENTER REGISTRY IN FUKUSHIMA CITY FOR LEFT MAIN CORONARY ARTERY DISEASE: BARE METAL STENT VERSUS DRUG-ELUTING STENT

An appropriate treatment strategy for left main trunk (LMT) lesions is still controversial in the drug-eluting stent (DES) era. Consecutive LMT stenting cases (n = 155) between January 2008 and January 2013 in 4 hospitals in Fukushima city were retrospectively analyzed. We excluded the patients suffering from cardiogenic shock before the stenting procedure. Among those cases, 60 patients had acute coronary syndrome, and remaining 95 had stable angina pectoris. Out of 155 cases, 45 patients were treated with bare metal stents (BMSs) and 110 patients were treated with DESs. All cases were succeeded in the initial procedure. Mean stent size of BMS was 3.85 ± 0.34 mm while that of DES was 3.46 ± 0.17 mm (P<0.001). At the follow up coronary angiography (255-day on average), % stenosis of BMS group was 26.6 ± 15.0% and that of DES group was 20.4 ± 12.6% (P = 0.006). The mean observation period for clinical events was 738.8 ± 480.3 days. Major adverse cardiac events-free rates for each group were compared and no significant differences were evident between the 2 groups (11.1% vs. 19.1%, ns). The present study demonstrated that use of BMSs would be a viable option in the treatment of LMT lesions when it is possible to use a large-sized stent (>3.5 mm).

Progress in interventional cardiology: challenges for the future

Cardiovascular disease is the leading cause of death in the western and developing countries. Percutaneous transluminal coronary interventions have become the most prevalent treatment option for coronary artery disease; however, due to serious complications, such as stent thrombosis and in-stent restenosis (ISR), the efficacy and safety of the procedure remain important issues to address. Strategies to overcome these aspects are under extensive investigation. In this review, we summarise relevant milestones during the time to overcome these limitations of coronary stents, such as the development of polymer-free drug-eluting stents (DES) to avoid pro-inflammatory response due to the polymer coating or the developement of stents with cell-directing drugs to, simultaneously, improve re-endothelialisation and inhibit ISR amongst other techniques most recently developed, which have not fully entered the clinical stage. Also the novel concept of fully biodegradable DES featured by the lack of a permanent foreign body promises to be a beneficial and applicable tool to restore a natural vessel with maintained vasomotion and to enable optional subsequent surgical revascularisation.

Impact of stent strut design in metallic stents and biodegradable scaffolds

Advances in the understanding of healing mechanisms after stent implantation have led to the recognition of stent strut thickness as an essential factor affecting re-endothelialization and overall long term vessel healing response after Percutaneous Coronary Interventions (PCI). Emergence of Drug-eluting stents (DESs) with anti-proliferative coating has contributed to reducing the incidence of restenosis and Target Lesion Revascularization (TVR), while progress and innovations in stent materials have in the meantime facilitated the design of newer platforms with more conformability and thinner struts, producing lesser injury and improving integration into the vessel wall. Recent advances in biodegradable metal and polymer materials now also allow for the design of fully biodegradable platforms, which are aimed at scaffolding the vessel only temporarily to prevent recoil and constrictive remodeling of the vessel during the initial period required, and are then progressively resorbed thereby avoiding the drawback of leaving an unnecessary implant permanently in the vessel. The aim of this article is to review recent evolution in stent material and stent strut design while understanding their impact on PCI outcomes. The article describes the different metallic alloys and biodegradable material properties and how these have impacted the evolution of stent strut thickness and ultimately outcomes in patients.

Efficacy and safety of drug-eluting stents in the real world: 8-year follow-up

Background:

Drug-eluting stents have been used in daily practice since 2002, with the clear advantages of reducing the risk of target vessel revascularization and an impressive reduction in restenosis rate by 50%-70%. However, the occurrence of a late thrombosis can compromise long-term results, particularly if the risks of this event were sustained. In this context, a registry of clinical cases gains special value.

Objective:

To evaluate the efficacy and safety of drug-eluting stents in the real world.

Methods:

We report on the clinical findings and 8-year follow-up parameters of all patients that underwent percutaneous coronary intervention with a drug-eluting stent from January 2002 to April 2007. Drug-eluting stents were used in accordance with the clinical and interventional cardiologist decision and availability of the stent.

Results:

A total of 611 patients were included, and clinical follow-up of up to 8 years was obtained for 96.2% of the patients. Total mortality was 8.7% and nonfatal infarctions occurred in 4.3% of the cases. Target vessel revascularization occurred in 12.4% of the cases, and target lesion revascularization occurred in 8% of the cases. The rate of stent thrombosis was 2.1%. There were no new episodes of stent thrombosis after the fifth year of follow-up. Comparative subanalysis showed no outcome differences between the different types of stents used, including Cypher®, Taxus®, and Endeavor®.

Conclusion:

These findings indicate that drug-eluting stents remain safe and effective at very long-term follow-up. Patients in the "real world" may benefit from drug-eluting stenting with excellent, long-term results.

Association between low serum magnesium level and major adverse cardiac events in patients treated with drug-eluting stents for acute myocardial infarction

Objectives

We investigated the association of serum magnesium (Mg) levels and major adverse cardiac events (MACEs) after drug-eluting stent (DES) implantation.

Background

Mg depletion plays a key role in the pathphysiologic features of diabetes mellitus, hypertension, thrombosis, arrhythmias and coronary artery disease. Whether the depletion is related to the long-term prognosis of DES implantation is not known.

Methods

From 2008 to 2011, we enrolled 414 consecutive patients <50 years old who underwent DES implantation for acute coronary syndrome. Serum Mg level was analyzed and patients were followed up for a median of 24 months (interquartile range 14–32 months) for the occurrence of MACEs defined as death, myocardial infarction, stroke, and any revascularization.

Results

For patients with unstable angina, no significant association between serum Mg level and MACEs was found in the multivariate model. For patients with myocardial infarction, after adjusting for age, positive family history, smoking status, hypertension, hypercholesterolemia, and diabetes at baseline, the risk was 8.11-fold higher for patients with quartile 1 than 4 Mg level (95% confidence interval 1.7–38.75; P<0.01). In addition, when tested as a continuous variable, serum magnesium was a significant predictor for MACEs of acute myocardial infarction (HR [per 0.1 mM increase], 0.35 [95% CI, 0.19–0.63], p< 0.01), after adjustment for other confounders.

Conclusions

Low serum level of Mg may be an important predictor of MACEs with DES implantation for acute myocardial infarction. Further research into the effectiveness of Mg supplementation for these patients is warranted.

The effects of novel, bioresorbable scaffolds on coronary vascular pathophysiology

Percutaneous coronary intervention (PCI) has rapidly evolved over the past 30 years as technology has sought to improve clinical outcomes by addressing pathophysiologic complications arising from the intervention. Stents were designed to resolve the drawbacks of balloon angioplasty by providing radial support to prevent vessel recoil, by sealing coronary dissections, and by preventing abrupt vessel closure. The conceptualization of an ideal drug-eluting fully bioresorbable scaffold (BRS), whether metallic or polymeric, would theoretically address the adverse aspects of permanent metallic stents. In this review of the literature, we will discuss the impact these novel fully BRS platforms have on vascular pathophysiology following PCI.

Metallic implant drug/device combinations for controlled drug release in orthopaedic applications

The study of metallic drug/device combinations for controlled drug release in orthopaedic applications has gained significant momentum in the past decade, particularly for the prevention and reduction of implant associated infection. Such combinations are commonly based upon a permanent metallic implant (such as stainless steel or titanium) and are then coated with a drug-eluting polymer or ceramic system. Drug elution is also possible from the implant itself by utilising metallic foams, porous architectures and bioresorbable metals. This review will explore the current research into metallic implant drug/device combinations via a critical review of the relevant literature.

Post-operative simultaneous very late two-vessel drug eluting stent thrombosis with sparing of bare metal stent in a Jehovah's witness after clopidogrel withdrawal

Very late stent thrombosis is a feared complication after drug-eluting stent (DES) implantation. Several factors related to the patient, generation and type of the deployed stent, procedure, and premature antiplatelet withdrawal are known to contribute to this complication. Herein, we describe a case of a Jehovah's witness patient who developed simultaneous two-vessel 1st generation DES thrombosis 5.4 and 3.5 years after deployment [with sparing of the bare metal stent (BMS)] in the immediate post-operative period secondary to clopidogrel withdrawal. The case was complicated by ST-segment elevation myocardial infarction, cardiogenic shock, and a ventricular fibrillation cardiac arrest requiring urgent percutaneous coronary intervention. The acute thrombosis of DESs with sparing of the BMS exemplify how they are more prone to this complication due to delayed endothelialization of stent struts and neoinitimal coverage. <Learning objective: Extreme caution should be excercised when attempting to withdraw antiplatelets immediately before surgery in patients with drug eluting stents even if the recomended 12-month period of dual antiplatelet therapy has elapsed because of the risk of very late stent thrombosis.>.

Elutax paclitaxel-eluting balloon followed by bare-metal stent compared with Xience V drug-eluting stent in the treatment of de novo coronary stenosis: a randomized trial

BACKGROUND

Paclitaxel-eluting balloons (PEBs) are a promising alternative to drug-eluting stent (DES) in the treatment of coronary stenoses. The aim of our study was to compare the 9-month restenosis rates of a strategy of predilatation with PEB followed by bare-metal CoCr stent (PEB + BMS group) versus implantation of everolimus DES (DES group).

METHODS

This randomized, single-center study planned to enroll 366 patients with stable angina (183 patients per arm) undergoing percutaneous coronary intervention of a de novo, native coronary artery stenosis ≤ 15 mm in length. Primary end point, in a noninferiority study design, was 9-month binary angiographic restenosis. A frequency-domain optical coherence tomography substudy investigated the percentage of uncovered stent struts per lesion, the percentage of malapposed/uncovered struts per lesion, and the percentage of net volume obstruction at 9-month follow-up among the first consecutive 30 patients enrolled in the PEB + BMS group.

RESULTS

The study was prematurely halted after enrollment of 125 patients, 59 in the PEB + BMS group and 66 in the DES group, because of excess of ischemia-driven target lesion revascularization in the PEB + BMS group. When all the enrolled patients completed their follow-up, IDLTR rates were 14% in the PEB + BMS versus 2% in DES group (P = .001). Binary restenosis, either in-stent or in-segment, was significantly higher in the PEB + BMS compared with DES group (17% vs 3% [P = .01] and 25% vs 4% [P = .009] respectively). Frequency-domain optical coherence tomography demonstrated important neointimal regrowth in the PEB + BMS group, similar to historical BMS data.

CONCLUSION

In the treatment of de novo coronary stenosis, a strategy of predilatation with PEB before BMS implantation was significantly inferior to implantation of an everolimus DES stent in terms of 9-month target lesion revascularization. Frequency-domain optical coherence tomography data confirm the lack of efficacy of this strategy.

Study design and rationale of "a multicenter, open-labeled, randomized controlled trial comparing three 2nd-generation drug-eluting stents in real-world practice" (CHOICE trial)

BACKGROUND

The second-generation drug-eluting stents (DES) have shown superiority in many studies relating to safety and efficacy when compared with the first-generation DES. However, it is unclear whether there are differences in efficacy and safety among the second-generation DES after long-term follow-up.

METHODS

This multicenter, prospective, randomized, open-labeled trial will directly compare the efficacy and safety among the patients treated with either everolimus-eluting stent (EES), zotarolimus-eluting stent with biolinx polymer (ZES-R), or biolimus-eluting stent (BES) with minimal exclusion criteria. The primary end point is a patient-oriented composite consisted of cardiac death, myocardial infarction not clearly attributable to a nontarget vessel and clinically indicated target lesion revascularization at 24-month clinical follow-up post-index procedure. With the hypothesis that "BES is non-inferior to EES" or "BES is non-inferior to ZES-R" in primary end point, approximately 2,600 patients will be assigned to one of the types of stents using a web-based randomization system.

CONCLUSIONS

The CHOICE trial will directly compare the efficacy and safety of EES, ZES-R, and BES in everyday clinical practice for long-term follow-up.

Safety and efficacy of overlapping homogenous drug-eluting stents in patients with acute myocardial infarction: results from Korea Acute Myocardial Infarction Registry

The aim of this study was to compare safety and efficacy of 4 homogenous overlapping drug-eluting stents (DES) in acute myocardial infarction (AMI) patients. We selected 1,349 consecutive patients (62.1 ± 14.9 yr, 69.4% male) who received homogenous overlapping DESs in diffuse de novo coronary lesions from Korea Acute Myocardial Infarction Registry from April 2006 through September 2010. They were divided into 4 groups based on type of DES implanted - Paclitaxel (PES), Sirolimus (SES), Zotarolimus (ZES) and Everolimus (EES)-eluting stents. Primary endpoint was 12-month MACE. We also studied EES versus other DESs (PES + SES + ZES). Mean stent length was 26.2 ± 7.5 mm and mean stent diameter was 3.1 ± 0.4 mm. Average number of stents used per vessel was 2.2 ± 0.5. Incidence of major adverse cardiac events (MACE) in PES, SES, ZES, and EES groups were 9.5%, 9.2%, 7.5%, and 3.8%, respectively (P = 0.013). In EES group, overall MACE and repeat revascularization were lowest, and no incidence of stent thrombosis was observed. Non-fatal MI was highest in PES, almost similar in SES and EES with no incidence in ZES group (P = 0.044). Cox proportional hazard analysis revealed no differences in the incidence of primary endpoint (P = 0.409). This study shows no significant differences in 12-month MACE among 4 groups.

Comparison between sirolimus- and paclitaxel-eluting stents for the treatment of older patients affected by coronary artery disease: results from a single-center allcomers registry

The treatment of elderly patients with coronary artery disease (CAD) is challenging because this population is complex and greatly expanding. Drug-eluting stents (DES) generally improve the outcome in high-risk cases. We evaluated the clinical impact of different first-generation DES, i.e., sirolimus-eluting stents (SES) and paclitaxel-eluting stents (PES), in this context. A prospective, nonrandomized, single-center, allcomers registry consecutively enrolling all patients aged ≥75 years eligible for percutaneous coronary intervention (PCI) with DES was carried out. Only one type of DES was implanted per protocol for each patient. Two groups were identified according to the type of implanted stent, i.e., SES and PES. The primary end point encompassed major adverse cardiac events (MACE), including death, myocardial infarction, and target lesion revascularization (TLR). The secondary end point encompassed the rate of definite/probable stent thrombosis and target vessel revascularization (TVR). From June 2004 to May 2008, 151 patients were enrolled. Among them, 112 (74.2%) received SES and 39 (25.8%) received PES. Baseline clinical characteristics were similar, while few angiographic features (ostial location, stent diameter, proximal reference vessel diameter) showed minor differences. At the median follow-up of 22.6 months, primary and secondary end points did not significantly differ in terms of MACE (SES 12.5% vs PES 20.5%, P = 0.3), death (SES 5.4% vs PES 7.7%, P = 0.7), myocardial infarction (SES 4.5% vs PES 10.3%, P = 0.2), TLR (SES 2.7% vs PES 2.6%, P = 1.0), stent thrombosis (SES 1.8% vs PES 5.1%, P = 0.3), and TVR (SES 1.8% vs PES 0%, P = 0.6). In this real-world population of elderly patients treated by DES-PCI for CAD, the overall efficacy and safety have been excellent in both DES, and the choice between SES and PES did not influence the clinical outcome.

Long-term effectiveness and safety of sirolimus drug-eluting stents

The root cause of coronary artery disease is atherosclerosis, ie, intraluminal narrowing (stenosis) of the arteries that supply blood to tissues of the heart. The introduction of the drug-eluting stent over the past decade has revolutionized the field of interventional cardiology. It is used extensively in clinical practice for the treatment of coronary artery disease. The first drug-eluting stent to receive US Food and Drug Administration approval was the sirolimus-eluting stent. Recently, two other stent analogs of sirolimus were approved, ie, the zotarolimus-eluting stent and the everolimus-eluting stent. However, concern has arisen in recent years about the long-term safety and efficacy of drug-eluting stents, due to the occurrence of late adverse clinical events, such as stent thrombosis. This review focuses on clinical studies that have been performed with the sirolimus-eluting stent or its analogs. We discuss the pharmacology, safety, and various therapeutic options that exist when choosing stents for coronary artery disease. Our aim is to provide a thorough review of the long-term efficacy and safety of sirolimus drug-eluting stents, and also to discuss currently approved and promising investigational drug-eluting stents, in an effort to provide insight into how these stents are currently evolving and generate further investigation in this area.

Consensus document: antithrombotic therapy in patients with atrial fibrillation undergoing coronary stenting. A North-American perspective

The optimal regimen of the anticoagulant and antiplatelet therapies in patients with atrial fibrillation who have had a coronary stent is unclear. It is well recognised that "triple therapy" with aspirin, clopidogrel, and warfarin is associated with an increased risk of bleeding. National guidelines have not made specific recommendations given the lack of adequate data. In choosing the best antithrombotic options for a patient, consideration needs to be given to the risks of stroke, stent thrombosis and major bleeding. This document describes these risks, provides specific recommendations concerning vascular access, stent choice, concomitant use of proton-pump inhibitors and the use and duration of triple therapy following stent placement based upon the risk assessment.

Cost-effectiveness of drug-eluting stents versus bare metal stents in clinical practice

BACKGROUND

Drug-eluting stents (DES) reduce the need for repeat target revascularization (TVR) compared with bare metal stents (BMS) but are more costly. The objective was to evaluate the cost-effectiveness of DES versus BMS.

METHODS AND RESULTS

We evaluated clinical outcomes and costs of care over 3 years in 1147 undergoing BMS before the availability of DES and 1247 DES patients at Wake Forest University Baptist Medical Center from 2002 to 2005. Costs for index stenting, TVR, and clopidogrel use were assessed. The 2 groups were well matched for baseline characteristics. Index stenting costs were $1846 higher per patient for DES versus BMS ($1737 more to $1950 more). At 3 years, absolute TVR rates were 15.2 per 100 DES patients and 24.1 per 100 BMS patients, and as a result, cumulative TVR-related costs were $2065 less per patient for DES versus BMS ($3001 less to $1134 less). Including the cost of clopidogrel, the incremental cost-effectiveness ratio per TVR avoided with DES was $4731 through 1 year, $4703 through 2 years, and $6379 through 3 years.

CONCLUSIONS

At 3 years, the higher index cost of DES versus BMS was completely offset by lower TVR-related costs. However, because of extended clopidogrel use for DES, the incremental cost-effectiveness ratio per TVR avoided ranged from $4703 to $6379 over 3 years. These unadjusted observational findings provide support for the continued use of DES in routine practice but highlight the important impact of prolonged dual antiplatelet use on the cost-effectiveness of this technology.

Comparison of the safety between first- and second-generation drug eluting stents: meta-analysis from 19 randomized trials and 16,924 patients

BACKGROUND/OBJECTIVE

Despite the effectiveness of first generation drug eluting stent, DES-1 (Taxus and Cypher) in avoiding restenosis and the need for new revascularizations, a slightly increase in stent thrombosis, ST have been published. Second generation drug eluting stent, DES-2 has been developed to optimize the results of percutaneous coronary intervention in terms of efficacy and safety, for avoiding early and late ST. Our objective was to compare the risk of ST between DES-1 and DES-2.

METHODS

We performed a meta-analysis of 19 randomized trials. Overall 16,924 patients; 7294 were allocated to DES-1 and 9630 were allocated to DES-2. The primary endpoint was to compare the risk of overall ST during the first year. Other clinical outcomes of interest were to compare the incidence of early (<1 month) and late ST (>1 month-<1 year).

RESULTS

The incidence of overall ST was not increased in patients receiving DES-1 (1.13% DES-1 vs 0.75% DES-2, OR 0.79, 95% CI:0.45-1.40, p 0.43). There were no significant differences in the incidence of; early ST (0.85% DES-1 vs 0.53% DES-2, OR 0.68, 95% CI:0.31-1.51, p 0.35) and late ST (0.40% DES-1 vs 0.25% DES-2, OR 0.69, 95% CI:0.39-1.24, p 0.22).

CONCLUSIONS

During the first year after stent implantation, we didn't found differences in ST between DES-1 and DES-2. Most of ST was produced under appropriate anti-platelet therapy so it is possible that many other factors such as; clopidogrel resistance, procedural complications or stent malapposition were implicated. Safety after longer follow-up (>1 year) remains unclear.

[New approaches and indications for the analysis of platelet function in cardiology]

Inhibiting platelet function is a key therapeutic principle in cardiology because platelets play a pivotal role in triggering cardiovascular events. In addition to acetylsalicylic acid, a cyclooxygenase inhibitor, ADP-receptor blockers are frequently used for anti-platelet therapy. This therapy does not abolish platelet activation and aggregation. Platelets may still be activated by alternative routes such as the thrombin receptor-mediated pathway. New, more potent inhibitors of platelet function continue to lower the risk of ischaemic events but several trials and clinical registries have also shown that this advantage was frequently offset by an increased risk of bleeding complications. As a consequence, the individual risk of ischaemia and bleeding of a patient must be taken into consideration to select the platelet inhibitor offering the best benefit-risk ratio. Modern laboratory diagnostics may help to achieve this goal by complementing functional platelet tests with pharmacogenomic analyses consistent with the idea of "personalized medicine".