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

Individualization of Duration of Dual Antiplatelet Therapy after Coronary Stenting: A Comprehensive, Evidence-Based Review

Dual antiplatelet therapy (DAPT), comprising aspirin and a P2Y12 receptor inhibitor, is the cornerstone of post-percutaneous coronary intervention treatment to prevent stent thrombosis and reduce the risk of adverse cardiovascular events. The selection of an optimal DAPT regimen, considering the interplay of various antiplatelet agents, patient profiles, and procedural characteristics, remains an evolving challenge. Traditionally, a standard duration of 12 months has been recommended for DAPT in most patients. While contemporary guidelines provide general frameworks, DAPT modulation with longer or shorter treatment courses followed by aspirin or P2Y12 inhibitor monotherapy are evolving towards an individualized strategy to optimize the balance between efficacy and safety. This review comprehensively examines the current landscape of DAPT strategies after coronary stenting, with a focus on emerging evidence for treatment individualization.

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.

Recurrent intraventricular thrombus six months after ST-elevation myocardial infarction in a diabetic man: a case report

BACKGROUND

Percutaneous coronary intervention with placement of a drug-eluting stent in a diabetic patient with ST-elevation myocardial infarction is a relatively common procedure, and always requires subsequent treatment with dual antiplatelet therapy. It is sometimes necessary to add oral anticoagulation therapy because of individual clinical circumstances, which further increases the risk of bleeding.

CASE PRESENTATION

A 66-year-old hypertensive diabetic man with a history of gastrointestinal bleeding was admitted with an ST-elevation inferior myocardial infarction that had been evolving over 72 h. Electrocardiography showed ST segment elevation in the inferior leads and Q waves in the inferior and anterior leads. He reported a similar episode of chest pain 1 month previously, for which he had not sought medical treatment. Coronary angiography showed chronic occlusion of the mid-left anterior descending coronary artery, and acute occlusion of the mid-right coronary artery. He was treated by percutaneous coronary intervention, with placement of a drug-eluting stent in the right coronary artery. Soon after admission, transthoracic echocardiography showed abnormal left ventricular contractility and a large left intraventricular thrombus. Three weeks after admission, the patient was discharged on dual antiplatelet therapy (clopidogrel and aspirin) and oral anticoagulation therapy (acenocoumarol). Four months after discharge, transthoracic echocardiography showed absence of left ventricular thrombus and resolution of the abnormal contractility in the area supplied by the revascularized right coronary artery. Given the high risk of bleeding, oral anticoagulation therapy was stopped. Six months later, transthoracic echocardiography showed recurrent left ventricular apical thrombus, and an underlying hypercoagulable state was ruled out. Oral anticoagulation therapy was restarted on an indefinite basis, and dual antiplatelet therapy was continued.

CONCLUSIONS

The present case illustrates the need for repeat transthoracic echocardiography following the withdrawal of oral anticoagulation therapy in patients with ST-elevation myocardial infarction, both to monitor thrombus status and to assess left ventricular segmental contraction. In patients who require anticoagulation, avoidance of a drug-eluting stent is strongly preferred and second-generation stents are recommended. The alternative regimen of oral anticoagulation and clopidogrel may be considered in this scenario. In patients with recurrent intraventricular thrombus an underlying hypercoagulable state should be ruled out.

Triple oral antithrombotic therapy in atrial fibrillation and coronary artery stenting

Patients with atrial fibrillation affected by an acute coronary syndrome have indications for oral anticoagulation and dual antiplatelet therapy with aspirin and a P2Y12 adenosine diphosphate receptor inhibitor after coronary artery stenting. The concurrent use of all 3 agents, termed triple oral antithrombotic therapy, significantly increases the risk of bleeding. To date, there is a lack of evidence on the proper combination and duration of anticoagulant and antiplatelet agents in patients with indications for both therapies. As such, care has been guided by expert opinion, and there is wide variation in clinician practice. In this review, the latest evidence on the risks and benefits of triple oral antithrombotic therapy in patients with atrial fibrillation after coronary artery stenting is summarized. We discuss the clinical risk scores useful in guiding the prediction of stroke, bleeding, and stent thrombosis. Additionally, we highlight where additional evidence is needed to determine the proper balance of anticoagulant and antiplatelet agents in this patient population.

Safety and efficacy of everolimus- versus sirolimus-eluting stents: a systematic review and meta-analysis of 11 randomized trials

BACKGROUND

While EES have proven superior to paclitaxel-eluting stents, it remains uncertain whether EES improve clinical outcomes compared to SES, which are the most efficacious among the first-generation drug-eluting stents. We performed a meta-analysis of randomized trials comparing the efficacy and safety of everolimus-eluting stents (EES) versus sirolimus-eluting stents (SES) in patients undergoing percutaneous coronary intervention.

METHODS

From online and offline search until December 2011, we identified 11 randomized trials (total 12,869 patients). The primary endpoint was major adverse cardiac events.

RESULTS

The risk of major adverse cardiac events did not differ significantly between the patients treated with EES versus SES [OR, 0.90 (95% CI, 0.77-1.04); P = .162]. However, we found a significant reduction in the risk of repeat revascularization in the EES arm [OR, 0.85 (95% CI, 0.71-1.00); P = .047]. There were no significant differences regarding the risk of cardiac death [OR, 0.97 (95% CI, 0.74-1.27); P = .834], or myocardial infarction [OR, 0.95 (95% CI, 0.75-1.20), P = .656]. The risk of definite or probable stent thrombosis tended to be lower [OR, 0.68 (95% CI, 0.45-1.02); P = .065], while definite ST was significantly lower [OR, 0.44 (95% CI, 0.25-0.80); P = .007] with EES.

CONCLUSIONS

In a large systematic overview of comparative trials involving percutaneous revascularization with drug-eluting stents, treatment with EES significantly reduced the risk of repeat revascularization and definite ST compared to SES. We found no significant differences in the risk of cardiac death or myocardial infarction.

Six-month versus 12-month dual antiplatelet therapy after implantation of drug-eluting stents: the Efficacy of Xience/Promus Versus Cypher to Reduce Late Loss After Stenting (EXCELLENT) randomized, multicenter study

BACKGROUND

The optimal duration of dual antiplatelet therapy (DAPT) after implantation of drug-eluting coronary stents remains undetermined. We aimed to test whether 6-month DAPT would be noninferior to 12-month DAPT after implantation of drug-eluting stents.

METHODS AND RESULTS

We randomly assigned 1443 patients undergoing implantation of drug-eluting stents to receive 6- or 12-month DAPT (in a 1:1 ratio). The primary end point was a target vessel failure, defined as the composite of cardiac death, myocardial infarction, or ischemia-driven target vessel revascularization at 12 months. Rates of target vessel failure at 12 months were 4.8% in the 6-month DAPT group and 4.3% in the 12-month DAPT group (the upper limit of 1-sided 95% confidence interval, 2.4%; P=0.001 for noninferiority with a predefined noninferiority margin of 4.0%). Although stent thrombosis tended to occur more frequently in the 6-month DAPT group than in the 12-month group (0.9% versus 0.1%; hazard ratio, 6.02; 95% confidence interval, 0.72-49.96; P=0.10), the risk of death or myocardial infarction did not differ in the 2 groups (2.4% versus 1.9%; hazard ratio, 1.21; 95% confidence interval, 0.60-2.47; P=0.58). In the prespecified subgroup analysis, target vessel failure occurred more frequently in the 6-month DAPT group than in the 12-month group (hazard ratio, 3.16; 95% confidence interval, 1.42-7.03; P=0.005) among diabetic patients.

CONCLUSIONS

Six-month DAPT did not increase the risk of target vessel failure at 12 months after implantation of drug-eluting stents compared with 12-month DAPT. However, the noninferiority margin was wide, and the study was underpowered for death or myocardial infarction. Our results need to be confirmed in larger trials.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00698607.

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

OBJECTIVES

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Drug-eluting 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.

Current and future drug-eluting coronary stent technology

Despite the impressive benefits obtained following the introduction of the drug-eluting stent, safety concerns have been raised over their long-term safety with particular regard to stent thrombosis. Various mechanisms such as delayed endothelialization, local hypersensitivity and endothelial dysfunction owing to the durable polymer coating and/or the drug itself have been suggested as possible causes of this phenomenon. Therefore, to address these concerns, a newer-generation of drug-eluting stents has been developed and they are currently undergoing preclinical and clinical evaluation in order to increase both the safety and biocompatibility by optimizing the three major components of drug-eluting stents: the stent platform, the polymer and the drug. This article critically reviews the key clinical trials and the current status of these new coronary devices as well as preventing future perspectives for their continued development.

Everolimus-eluting stents: update on current clinical studies

Everolimus-eluting stents (EES) have become the most commonly implanted coronary stents worldwide. This review describes and analyzes the clinical data supporting the use of EES, focusing primarily on published, randomized, controlled trials. Everolimus-eluting stents have been shown to have less restenosis, stent thrombosis, and periprocedural myocardial infarction compared with earlier generation paclitaxel-eluting stents (PES). Lower rates of adverse events for EES compared with PES were generally seen in all subgroups, with the notable exception of patients with diabetes mellitus. There have been fewer, randomized, clinical trials comparing EES with either sirolimus-eluting stents or zotarolimus-eluting stents, although very good results with EES have been observed in the trials that have been performed. Recent clinical trial data suggest that this excellent safety and efficacy profile is maintained in a next-generation EES designed to have improved mechanical properties and radiopacity.

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.

The real world experience of the everolimus-eluting coronary stent system: audit of everolimus-eluting coronary stents

AIMS

To investigate the safety and efficacy of everolimus-eluting stents (EES) in a real world population, including those with high-risk characteristics and complex lesions.

METHODS

In this report, we analyze 2-year outcomes in 500 consecutive unselected patients treated with EES between April 2007 and March 2008. All patients were followed for 2 years for adverse events.

RESULTS

There were 995 EES deployed in 792 lesions. The indication for the coronary procedure was acute coronary syndrome in 94.2% of patients. Bifurcations were involved in 21% of lesions, 3.5% degenerated vein grafts, 2.7% left main stem stenoses, 33% multivessel disease, 4.5% in-stent restenosis, and 79.1% AHA/ACC classification B2/C lesions. The major adverse cardiac event rate (composite of cardiovascular death, acute myocardial infarction, target lesion revascularization) was 10.6%. Target lesion revascularization was required in 4.0% patients, 1.4% for in-stent thrombosis. These event rates are comparable with studies involving lower risk patients and less complex coronary lesions.

CONCLUSION

The use of EES, even in this real world, high-risk population, continues to demonstrate safety and efficacy rates comparable with current studies in more selected patient groups and, therefore, may justify current practice to utilize EES in "off label" situations.

3-year clinical follow-up of the XIENCE V everolimus-eluting coronary stent system in the treatment of patients with de novo coronary artery lesions: the SPIRIT II trial (Clinical Evaluation of the Xience V Everolimus Eluting Coronary Stent System in the Treatment of Patients with de novo Native Coronary Artery Lesions)

OBJECTIVES

This paper reports the 3-year clinical outcomes of the XIENCE V (Abbott Vascular, Santa Clara, California) everolimus-eluting stent (EES) compared with the TAXUS (Boston Scientific, Natick, Massachusetts) paclitaxel-eluting stent (PES) in the randomized SPIRIT II (Clinical Evaluation of the Xience V Everolimus Eluting Coronary Stent System in the Treatment of Patients with de novo Native Coronary Artery Lesions) study.

BACKGROUND

The Xience V EES is a new-generation drug-eluting stent (DES) that might offer advantages over the first-generation DES in terms of improved clinical outcomes and a better safety profile.

METHODS

The SPIRIT II trial was a multicenter, prospective, randomized, single-blind, clinical trial, randomizing 300 patients with de novo coronary artery lesions in a ratio of 3:1 to either EES or PES. The primary end point was in-stent late loss at 180 days.

RESULTS

At 3-year clinical follow-up cardiac death was numerically lower with EES than PES (0.5% vs. 4.3%, p = 0.056). The observed rate of myocardial infarction was 3.6% for EES and 7.2% for PES (p = 0.31). The rate of ischemia-driven target lesion revascularization was 4.6% and 10.1% for EES and PES, respectively (p = 0.14). Overall, there was a trend for lower major adverse cardiovascular events in the EES group compared with PES (7.2% vs. 15.9%, p = 0.053). The rate of stent thrombosis was low and comparable in both groups (EES 1.0% vs. PES 2.9%).

CONCLUSIONS

The present study reports the favorable 3-year clinical outcomes of the EES, which are consistent with the results from other studies of the EES with shorter follow-up.

Update on the everolimus-eluting coronary stent system: results and implications from the SPIRIT clinical trial program

Drug-eluting stents (DES) have had a major impact in interventional cardiology. Compared to bare metal stents, they significantly reduce restenosis and the need for target vessel revascularization. Four DES are available in the US, the first-generation sirolimus-eluting (Cypher^®) and paclitaxel-eluting (Taxus^®) stents and later approved second-generation everolimus-eluting (Xience V^®) and zotarolimus-eluting (Endeavor^®) stents. The Xience V stent was approved on the basis of clinical efficacy and safety data from 3 studies in the SPIRIT clinical trial program. Within this trial series, the Xience V was superior to its bare metal stent counterpart, the Vision® stent, and noninferior to the paclitaxel-eluting stent for target vessel failure at 9 months. This review provides a comprehensive assessment of the data derived from both the pre- and post-approval randomized controlled trials and registry studies of Xience V that comprise the SPIRIT clinical trial program including recently published mid-term outcomes. The implications of the results in terms of interventional practice will be discussed.