Rationale and design of the EXAMINATION trial: a randomised comparison between everolimus-eluting stents and cobalt-chromium bare-metal stents in ST-elevation myocardial infarction

Ten-year prognostic impact of target versus non-target vessel failure after STEMI. Insight from the EXAMINATION-EXTEND trial

INTRODUCTION AND OBJECTIVES

After ST-segment myocardial infarction (STEMI), the impact of different adverse events on prognosis remains unknown. We aimed to assess very long-term predictors of patient-oriented composite endpoints (POCE) and investigate whether the occurrence of target vessel failure (TVF) vs a non-TVF event as the first event could potentially influence subsequent outcomes.

METHODS

The EXAMINATION-EXTEND trial randomized STEMI patients to receive either an everolimus-eluting stent or a bare-metal stent. The follow-up period was 10 years. Predictors of POCE (a composite of all-cause death, any myocardial infarction, or any revascularization) were evaluated in the overall study population. The patients were stratified based on the type of first event (TVF-first vs non-TVF-first) and were compared in terms of subsequent POCE. TVF was defined as a composite of cardiac death, TV myocardial infarction, or TV revascularization.

RESULTS

Out of the 1498 enrolled patients, 529 (35.3%) experienced a POCE during the 10-year follow-up. Independent predictors of POCE were age, diabetes mellitus, previous myocardial infarction, peripheral arterial disease, and multivessel coronary disease. The first event was a TVF in 296 patients and was a non-TVF in 233 patients. No significant differences were observed between TVF-first and non-TVF-first patients in terms of subsequent POCE (21.7% vs 39.3%, time ratio 1.79; 95%CI, 0.87-3.67;P=.12) or its individual components.

CONCLUSIONS

At the 10-year follow-up, approximately one-third of STEMI patients had experienced at least 1 POCE. Independent predictors of these events were age, diabetes, and more extensive atherosclerotic disease. The occurrence of a TVF or a non-TVF as the first event did not seem to influence subsequent outcomes.

TRIAL REGISTRATION NUMBER

NCT04462315.

Relationship between stent length and very long-term target lesion failure following percutaneous coronary intervention for ST-elevation myocardial infarction in the drug-eluting stents era: insights from the EXAMINATION-EXTEND study

BACKGROUND

Little data exist on the relationship between total stent length (TSL) and cardiovascular outcomes at very-long follow-up in patients with ST-elevation myocardial infarction (STEMI) in the 2nd generation drug-eluting stents (DES) era.

AIM

To analyze the relationship between TSL and 10-year target-lesion failure (TLF) in STEMI patients treated with percutaneous coronary intervention enrolled in the EXAMINATION-EXTEND.

METHODS

The EXAMINATION-EXTEND was an extended-follow-up study of the EXAMINATION trial, which randomized 1:1 STEMI patients to receive DES or bare metal stent (BMS). The primary endpoint was TLF, defined as a composite of target lesion revascularization (TLR), target vessel myocardial infarction (TVMI), or definite/probable stent thrombosis (ST). Relationship between stent length and TLF was evaluated in the whole study group in a multiple-adjusted Cox regression model with TSL as a quantitative variable. Subgroup analysis was also performed according to stent type, diameter, and overlap.

RESULTS

A total of 1,489 patients with a median TSL of 23 mm (Q1-Q318-35 mm) were included. TSL was associated with TLF at 10 years (adjusted HR per 5 mm increase of 1.07; 95% CI, 1.01-1.14; P = .02). This effect was mainly driven by TLR and was consistent regardless of stent type, diameter, or overlap. There was no significant relationship between TSL and TV-MI or ST.

CONCLUSIONS

In STEMI patients, there is a direct relationship between TSL implanted in the culprit vessel and the risk of TLF at 10 years, mainly driven by TLR. The use of DES did not modify this association.

Impact of Age at the Time of the First ST-Elevation Myocardial Infarction on 10-Year Outcomes (from the EXAMINATION-EXTEND Trial)

The aim of this substudy of the EXAMINATION-EXTEND was to analyze 10-year outcomes according to the patient's age at the time of the first ST-elevation myocardial infarction (STEMI). Of 1,498 patients with STEMI included in the EXAMINATION-EXTEND study, those with a previous history of coronary ischemic even or ischemic stroke were excluded from this analysis. The remaining 1,375 patients were divided into 4 age groups: <55, 55 to 65, 65 to 75, and >75 years. The primary end point was 10-year patient-oriented composite end point (POCE) of all-cause death, any MI, or any revascularization. At 10-year follow-up, patients aged <55 years (adjusted hazard ratio [HR] 0.24, 95% confidence interval [CI] 0.18 to 0.31, p = 0.001), 55 to 65 years (adjusted HR 0.26, 95% CI 0.20 to 0.34, p = 0.001), and 65 to 75 years (adjusted HR 0.38, 95% CI 0.30 to 0.50, p = 0.001) showed lower risk of POCE than those aged >75 years, led by a lower incidence of all-cause death (<55 : 6% vs 55 to 65: 11.9% vs 65 to 75: 25.7% vs >75 years: 61.6%, p = 0.001). Cardiac death was more prevalent in the older group (<55: 3.7% vs 55 to 65: 5.8% vs 65 to 75: 10.9% vs >75 years: 35.5%, p = 0.001). In the landmark analyses, between 5- and 10-year follow-up, young patients exhibited a higher incidence of any revascularization (<55: 7.4% vs 55 to 65: 4.9% vs 65 to 75: 1.8% vs >65 years: 1.6%, p = 0.001). In conclusion, in patients with a first STEMI, advanced age was associated with high rates of POCE at 10-year follow-up due to all-cause and cardiac death. Conversely, younger patients exhibited a high risk of revascularization at long-term follow-up.

Gender Differences in 10-Year Outcomes Following STEMI: A Subanalysis From the EXAMINATION-EXTEND Trial

BACKGROUND

Short-term outcomes following ST-segment elevation myocardial infarction (STEMI) in women are worse than in men, with a higher mortality rate. It is unknown whether gender plays a role in very long term outcomes.

OBJECTIVES

The aim of this study was to assess whether very long term outcomes following STEMI treatment are influenced by gender.

METHODS

EXAMINATION-EXTEND (10-Year Follow-Up of the EXAMINATION Trial) was an investigator-driven 10-year follow-up of the EXAMINATION (A Clinical Evaluation of Everolimus Eluting Coronary Stents in the Treatment of Patients With ST-Segment Elevation Myocardial Infarction) trial, which randomly 1:1 assigned 1,498 patients with STEMI to receive either everolimus-eluting stents or bare-metal stents. The present study was a subanalysis according to gender. The primary endpoint was the composite patient-oriented endpoint (all-cause death, any myocardial infarction, or any revascularization) at 10 years. Secondary endpoints were individual components of the primary endpoint. All endpoints were adjusted for age.

RESULTS

Among 1,498 patients with STEMI, 254 (17%) were women. Overall, women were older, with more arterial hypertension and less smoking history than men. At 10 years, no difference was observed between women and men for the patient-oriented composite endpoint (40.6% vs 34.2%; adjusted HR: 1.14; 95% CI: 0.91-1.42; P = 0.259). There was a trend toward higher all-cause death in women vs men (27.6% vs 19.4%; adjusted HR: 1.30; 95% CI: 0.99-1.71; P = 0.063), with no difference in cardiac death or other endpoints.

CONCLUSIONS

At very long term follow-up, there were no differences in the combined patient-oriented endpoint between women and men, with a trend toward higher all-cause death in women not driven by cardiac death. The present findings underline the need for focused personalized medicine in women after percutaneous revascularization aimed at both cardiovascular and gender-specific risk factor control and targeted treatment. (10-Years Follow-Up of the EXAMINATION Trial [EXAMINAT10N]; NCT04462315).

Second generation drug-eluting stents: a focus on safety and efficacy of current devices

Introduction: Percutaneous coronary intervention (PCI) represents the most frequent procedure performed in medicine. Second generation drug eluting stents (DES) have been developed to reduce the rates of late and very late complications of first generation DES.Areas covered: To improve long-term efficacy and safety of patients undergoing PCI, second generation DES have been developed with novel stent platforms, biocompatible durable and biodegradable polymers and newer antiproliferative agents. In this review we provide an overview of second generation DES and their clinical trials, discussing safety and effectiveness of these devices, and outlining clinical indication for use.Expert commentary: Numerous clinical trials have demonstrated the safety and efficacy of second generation DES over the last decade. These devices represent the gold standard treatment in stable and acute coronary syndromes.

10-Year Follow-Up of Patients With Everolimus-Eluting Versus Bare-Metal Stents After ST-Segment Elevation Myocardial Infarction

BACKGROUND

Outcomes data for a durable-polymer everolimus-eluting stent (EES) at extended long-term follow-up in patients with ST-segment elevation myocardial infarction (STEMI) are unknown.

OBJECTIVES

The aim of this study was to assess the 10-year outcomes of patients enrolled in the EXAMINATION (A Clinical Evaluation of Everolimus Eluting Coronary Stents in the Treatment of Patients With ST-Segment Elevation Myocardial Infarction) trial.

METHODS

The EXAMINATION-EXTEND (10-Years Follow-Up of the EXAMINATION Trial) study is an investigator-driven 10-year follow-up of the EXAMINATION trial, which randomly assigned 1,498 patients with STEMI in a 1:1 ratio to receive either EES (n = 751) or bare-metal stents (n = 747). The primary endpoint was a patient-oriented composite endpoint of all-cause death, any myocardial infarction, or any revascularization. Secondary endpoints included a device-oriented composite endpoint of cardiac death, target vessel myocardial infarction, or target lesion revascularization; the individual components of the combined endpoints; and stent thrombosis.

RESULTS

Complete 10-year clinical follow-up was obtained in 94.5% of the EES group and 95.9% of the bare-metal stent group. Rates of the patient-oriented composite endpoint and device-oriented composite endpoint were significantly reduced in the EES group (32.4% vs. 38.0% [hazard ratio: 0.81; 95% confidence interval: 0.68 to 0.96; p = 0.013] and 13.6% vs. 18.4% [hazard ratio: 0.72; 95% confidence interval: 0.55 to 0.93; p = 0.012], respectively), driven mainly by target lesion revascularization (5.7% vs. 8.8%; p = 0.018). The rate of definite stent thrombosis was similar in both groups (2.2% vs. 2.5%; p = 0.590). No differences were found between the groups in terms of target lesion revascularization (1.4% vs. 1.3%; p = 0.963) and definite or probable stent thrombosis (0.6% vs. 0.4%; p = 0.703) between 5 and 10 years.

CONCLUSIONS

At 10-year follow-up, EES demonstrated confirmed superiority in combined patient- and device-oriented composite endpoints compared with bare-metal stents in patients with STEMI requiring primary percutaneous coronary intervention. Between 5- and 10-year follow-up, a low incidence of adverse cardiovascular events related to device failure was found in both groups. (10-Years Follow-Up of the EXAMINATION Trial; NCT04462315).

Durable polymer everolimus-eluting stents: history, current status and future prospects

INTRODUCTION

Coronary percutaneous interventions have evolved from plain old balloon angioplasty (POBA) to stent implantation, which itself evolved from bare-metal stents (BMS) to the new biodegradable stents which try to restore endothelial function. Currently, the most commonly used stent is the everolimus-eluting stent.

AREAS COVERED

This review will cover the current status of durable polymer everolimus-eluting stent, its history, and future perspectives. Nowadays, the everolimus-eluting stent is the most used device in the acute and chronic settings due to its safety and efficacy.

EXPERT OPINION

Durable polymer everolimus-eluting stent, supported by much evidence, has demonstrated its efficacy and safety, not only in de novo artery lesions, but in multiples scenarios, such as the acute setting and diabetic population, becoming one of the most polyvalent stents available. Nowadays, research is focused on the reduction of antiplatelet treatment duration. Similar rates of stent thrombosis with short dual antiplatelet treatment regimens of 1 to 3 months compared to pronged treatment have been observed. However, specific studies should be performed to evaluate this possibility.

Long-term impact of diabetes in patients with ST-segment elevation myocardial infarction: Insights from the EXAMINATION randomized trial

BACKGROUND

Long-term outcomes of diabetic patients suffering from ST-segment elevation myocardial infarction (STEMI) and treated with second-generation drug-eluting stent have been scarcely evaluated. The aim of this posthoc subanalysis of the EXAMINATION trial was to compare 5-year outcomes according to the presence of diabetes mellitus.

METHODS

From a total of 1,497 patients included in the trial, 258 were diabetics (n = 137, received everolimus-eluting stent (EES) and n = 121 bare-metal stent (BMS); whereas 1,239 were nondiabetics (n = 613 treated with EES and n = 626 with BMS). Patient-oriented combined endpoint (POCE) defined as all-cause death, any MI or any revascularization, and other clinical parameters were collected up to 5-years. All results were adjusted for various potential confounders.

RESULTS

At 5-years, patients with diabetes showed similar rates of POCE between diabetics treated with EES and those treated with BMS (32.8% vs. 32.2%; p = 0.88). However, rates of TLR were significantly lower in the EES group (4.4% vs. 9.9%; HR 0.52 (0.29-0.94); P = 0.03). In non-diabetics, the use of EES was associated with a significant improvement in all-clinical parameters except for MI rate: POCE: [10.0% vs. 12.6%; HR 0.78(0.62-0.98); P = 0.038], all cause death: [7.0% vs. 12.1%; HR 0.62(0.42-0.90); P = 0.014], and [TLR: 4.2 vs. 6.7; HR 0.60 (0.37-0.98); P = 0.04]. Overall, diabetics showed higher rate of POCE at 5-years (32.6% vs. 21.5% in nondiabetics HR1.45[1.03-2.04];p = 0.03) driven by increased rates of MI and the need for revascularization that occurred in coronary segments remote from target lesions [2.7% vs. 1.1%; HR: 2.27 (1.12-5.23); P = 0.02 and 14% vs. 6.2%; HR: 2.11 (1.38-3.22); P = 0.001, respectively].

CONCLUSIONS

Diabetics had worse clinical outcomes than nondiabetics after STEMI mainly due to atherosclerosis progression. At 5-years, the treatment with EES did not reduce the rate of POCE in diabetics but reduced the need for revascularization compared with BMS.

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.

Cost-effectiveness of everolimus-eluting versus bare-metal stents in ST-segment elevation myocardial infarction: An analysis from the EXAMINATION randomized controlled trial

Background

Use of everolimus-eluting stents (EES) has proven to be clinically effective and safe in patients with ST-segment elevation myocardial infarction but it remains unclear whether it is cost-effective compared to bare-metal stents (BMS) in the long-term. We sought to assess the cost-effectiveness of EES versus BMS based on the 5-year results of the EXAMINATION trial, from a Spanish health service perspective.

Methods

Decision analysis of the use of EES versus BMS was based on the patient-level clinical outcome data of the EXAMINATION trial. The analysis adopted a lifelong time horizon, assuming that long-term survival was independent of the initial treatment strategy after the end of follow-up. Life-expectancy, health-state utility scores and unit costs were extracted from published literature and publicly available sources. Non-parametric bootstrapping was combined with probabilistic sensitivity analysis to co-assess the impact of patient-level variation and parameter uncertainty. The main outcomes were total costs and quality-adjusted life-years. The incremental cost-effectiveness ratio was expressed as cost per quality-adjusted life-years gained. Costs and effects were discounted at 3%.

Results

The model predicted an average survival time in patients receiving EES and BMS of 10.52 and 10.38 undiscounted years, respectively. Over the life-long time horizon, the EES strategy was €430 more costly than BMS (€8,305 vs. €7,874), but went along with incremental gains of 0.10 quality-adjusted life-years. This resulted in an average incremental cost-effectiveness ratio over all simulations of €3,948 per quality-adjusted life-years gained and was below a willingness-to-pay threshold of €25,000 per quality-adjusted life-years gained in 86.9% of simulation runs.

Conclusions

Despite higher total costs relative to BMS, EES appeared to be a cost-effective therapy for ST-segment elevation myocardial infarction patients due to their incremental effectiveness. Predicted incremental cost-effectiveness ratios were below generally acceptable threshold values.

Role of ST-Segment Resolution in Patients With ST-Segment Elevation Myocardial Infarction Treated With Primary Percutaneous Coronary Intervention (from the 5-Year Outcomes of the EXAMINATION [Evaluation of the Xience-V Stent in Acute Myocardial Infarction] Trial)

In patients with ST-segment elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (pPCI), lack of ST-segment resolution (STR) is associated with poor prognosis at short- and long-term follow-up. The aim of this study was to evaluate the role of STR on very long-term outcomes in patients with STEMI treated with pPCI included in the EXAMINATION (Evaluation of the Xience-V Stent in Acute Myocardial Infarction) trial. Patients were stratified according to the presence of STR < 50% and STR < 70% at the 30-minute post-pPCI electrocardiogram. Primary end point was the patient-oriented composite endpoint (POCE) of all-cause death, any myocardial infarction, or any revascularization at 5-year follow-up. Both baseline and post-PCI 30-minute electrocardiograms were available for STR assessment in 1,351 patients. Of these patients, 228 (16.9%) and 500 (37.0%) exhibited STR < 50% and STR < 70%, respectively. At 5-year follow-up, the POCE was observed more frequently in patients with STR < 50% (hazard ratio [HR] 1.556; 95% confidence interval [CI] 1.194 to 2.027; p <0.001) and in patients with STR < 70% (HR 1.460, 95% CI 1.169 to 1.824, p <0.001) compared with patients with STR > 50% and STR ≥ 70%, respectively. In both cases, this difference was mainly driven by a significant increase in the rate of all-cause death and any revascularization. After multivariable adjustment, STR < 70%, but not STR < 50%, resulted as a 5-year independent predictor of POCE (adjusted HR 1.338, 95% CI 1.008 to 1.778, p = 0.044). In conclusion, in patients with STEMI, the evaluation of 70% STR after pPCI provides independent prognostic information at 5-year follow-up and it can be used to identify patients at high risk of very long-term cardiovascular events.

Impact of Body Mass Index on 5-Year Clinical Outcomes in Patients With ST-Segment Elevation Myocardial Infarction After Everolimus-Eluting or Bare-Metal Stent Implantation

Patients with high body mass index (BMI) seem to have better outcomes after percutaneous coronary intervention than normal-weight patients. However, contrasting results have been reported on the "obesity paradox" in patients presenting with ST-elevation myocardial infarction (STEMI). The aim of our study was to investigate the impact of BMI on mortality in the population enrolled in the Evaluation of the Xience-V stent in Acute Myocardial INfArcTION (EXAMINATION) trial. The EXAMINATION trial randomized 1,498 patients with STEMI to a bare-metal stent or an everolimus-eluting stent. In this substudy patients were stratified into 3 groups according to BMI values: normal (BMI < 25 kg/m²), overweight (BMI = 25 to 29.9 kg/m²), and obese (BMI ≥ 30 kg/m²). The coprimary end points were the all-cause and cardiac deaths among the groups at the 5-year follow-up. BMI was available in 1,421 patients, divided in 401 (28.2%) normal, 702 (49.4%) overweight, and 318 (22.4%) obese. Obese patients were younger (p = 0.012) compared with the other groups, but with a worse cardiovascular risk profile. They were more frequently female (p <0.001) and with a higher rate of obesity-related co-morbidity conditions such as diabetes mellitus (p = 0.005), arterial hypertension (p <0.001), and hyperlipidemia (p = 0.001) compared with the other groups. At the 5-year follow-up, all-cause and cardiac deaths were less frequent in obese patients than in the other groups (p = 0.003 and p = 0.030, respectively). After adjustment for confounding variables, BMI was an independent predictor of all-cause death (hazard ratio 0.765, 95% confidence interval 0.599 to 0.979, p = 0.033), but not of cardiac death, without any interaction with the stent type. In conclusion, in patients with STEMI who underwent primary PCI, the long-term all-cause death rate decreased as BMI increased, confirming the obesity paradox, irrespective of the stent type.

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.

Selective use of contemporary drug-eluting stents in primary angioplasty for ST-elevation myocardial infarction: pooled analysis of COMFORTABLE AMI and EXAMINATION

AIMS

Selective use of DES only in patients at higher risk of MACE is common practice, particularly in healthcare systems with a large premium payable for DES. We aimed to identify subgroups of patients in which the use of BMS in primary percutaneous coronary intervention (PPCI) for STEMI can still be justified.

METHODS AND RESULTS

We performed a patient-level pooled analysis of COMFORTABLE AMI and EXAMINATION comparing contemporary DES with BMS in PPCI. A risk score was applied using three parameters: lesion length >15 mm, vessel size <3 mm, and diabetes mellitus. Individual data were available for 2,655 patients. The incidence of MACE at one year was incrementally higher in patients with risk scores of 1 or 2/3. MACE rates were lower in patients with a risk score 0 or 1 who were treated with DES (p=0.0073 and p=0.008). No difference in death or reinfarction was seen between DES and BMS in any group. There was a significant reduction in TLR with DES in all three groups.

CONCLUSIONS

A score comprising vessel size, lesion length, and diabetes did not identify patients at low risk with equivalent or better results from BMS use. The results suggest that the practice of only selective use of DES in primary PCI should be discouraged.

Clinical outcomes in patients with ST-segment elevation myocardial infarction treated with everolimus-eluting stents versus bare-metal stents (EXAMINATION): 5-year results of a randomised trial

BACKGROUND

Data for the safety and efficacy of new-generation drug-eluting stents at long-term follow-up, and specifically in patients with ST-segment elevation myocardial infarction, are scarce. In the EXAMINATION trial, we compared everolimus-eluting stents (EES) with bare-metal stents (BMS) in an all-comer population with ST-segment elevation myocardial infarction. In this study, we assessed the 5-year outcomes of the population in the EXAMINATION trial.

METHODS

In the multicentre EXAMINATION trial, done in Italy, Spain, and the Netherlands, patients with ST-segment elevation myocardial infarction were randomly assigned in a 1:1 ratio to receive EES or BMS. The random allocation schedule was computer-generated and central randomisation (by telephone) was used to allocate patients in blocks of four or six, stratified by centre. Patients were masked to treatment assignment. At 5 years, we assessed the combined patient-oriented outcome of all-cause death, any myocardial infarction, or any revascularisation. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00828087.

FINDINGS

1498 patients were randomly assigned to receive either EES (n=751) or BMS (n=747). At 5 years, complete clinical follow-up data were obtained for 731 patients treated with EES and 727 treated with BMS (97% of both groups). The patient-oriented endpoint occurred in 159 (21%) patients in the EES group versus 192 (26%) in the BMS group (hazard ratio 0·80, 95% CI 0·65-0·98; p=0·033). This difference was mainly driven by a reduced rate of all-cause mortality (65 [9%] vs 88 [12%]; 0·72, 0·52-0·10; p=0·047).

INTERPRETATION

Our findings should be taken as a point of reference for the assessment of new bioresorbable polymer-based metallic stents or bioresorbable scaffolds in patients with ST-segment elevation myocardial infarction.

FUNDING

Spanish Heart Foundation.

WITHDRAWN: Drug-eluting stents versus bare metal stents for angina or acute coronary syndromes

This review 'topic' has been included in work being carried out as part of a Health Technology Assessment commissioned by the National Institute for Clinical Excellence in England and Wales. Details of this research is available via www.nice.org.uk.

The views and opinions expressed herein are those of the authors and do not necessarily reflect those of the HTA programme, NICE, NIHR, NHS or the Department of Health.

The review has been split into 2 reviews that will be published as "Drug‐eluting stents versus bare‐metal stents for stable ischaemic heart disease" and "Drug‐eluting stents versus bare‐metal stents for acute coronary syndrome".

The editorial group responsible for this previously published document have withdrawn it from publication.

Sex-related Impact on Clinical Outcome of Everolimus-eluting Versus Bare-metal Stents in ST-segment Myocardial Infarction. Insights From the EXAMINATION Trial

INTRODUCTION AND OBJECTIVES

The use of second-generation drug-eluting stents compared with bare-metal stents in patients with ST-segment elevation myocardial infarction reduces the rate of major adverse cardiac events. We aimed to evaluate the impact of sex on the performance of everolimus-eluting stents vs bare-metal stents in ST-segment elevation myocardial infarction at 2-year follow-up.

METHODS

This is a sub-study of the EXAMINATION trial that randomized 1498 patients with ST-segment elevation myocardial infarction undergoing percutaneous coronary intervention to everolimus-eluting or bare-metal stents. Primary end point was combined all-cause death, any recurrent myocardial infarction, and any revascularization. All end points were analyzed according to sex at 2-year follow-up.

RESULTS

Of 1498 patients included in the trial, 254 (17.0%) were women. Women were older and had higher prevalence of hypertension and lower prevalence of smoking compared with men. In contrast with men, stent diameter was smaller in women. After multivariate analysis, the primary end point was similar between women and men (hazard ratio=0.95; 95% confidence interval, 0.66-1.37), and among women, between those treated with bare-metal vs everolimus-eluting stents (hazard ratio=2.48; 95% confidence interval, 0.95-6.46). Women showed a lower rate of repeat revascularization than men (hazard ratio=0.55; 95% confidence interval, 0.32-0.95) despite worse baseline characteristics. This difference was driven by better performance of the everolimus-eluting stent in women.

CONCLUSIONS

Despite poorer baseline clinical characteristics, women with ST-segment elevation myocardial infarction treated with percutaneous coronary intervention showed outcomes similar to men. The use of everolimus-eluting stents may represent an added value in women as it showed a reduced rate of repeated revascularization compared to men.

Everolimus-eluting stent versus bare-metal stent in elderly (≥75 years) versus non-elderly (<75 years) patients with ST-elevation myocardial infarction undergoing primary percutaneous coronary intervention: insights from the examination trial

BACKGROUND

The elderly (≥75years) constitute a high-risk subset of patients who continue to have a poorer prognosis than non-elderly (<75years). Whether the effects of everolimus-eluting stent (EES) in ST-segment elevation myocardial infarction (STEMI) are independent of age has not been reported. We investigated the outcomes following primary PCI (PPCI) with bare-metal stent (BMS) or EES in elderly vs. non-elderly STEMI patients.

METHODS

The EXAMINATION trial randomized 1498 STEMI patients to BMS or EES. The primary patient-oriented endpoint (POCE) was the combined of all-cause death, any-recurrent myocardial infarction (MI) and any-revascularization at 1-year. The secondary endpoint included the device-oriented combined (DOCE) of cardiac death, target-vessel MI and target-lesion revascularization. These endpoints and their components were compared between elderly and non-elderly.

RESULTS

Among patients enrolled in the trial, 245 (16.3%) were elderly, allocated to BMS (n=132) or EES (n=113), while the remaining 1253 (83.7%) were non-elderly, allocated to BMS (n=615) or EES (n=638). At 1-year, both the POCE and DOCE were observed more frequently in elderly vs. non-elderly group (24.5% vs. 10.5%, p<0.001 and 15.9% vs. 5.1%, p<0.001). Whereas in non-elderly, both POCE and DOCE were lower in EES vs. BMS (12.4% vs. 8.8%, p=0.03 and 6.7% vs. 3.6%, p=0.01), no differences were found in elderly, with a tendency for interaction between age and stent type for POCE (p=0.05). On multivariate analysis age ≥75 years was an independent predictor of POCE (HR 2.19 [95%CI 1.59-3.01], p<0.0001) and DOCE (HR 2.42 [95%CI 1.60-3.7], p<0.001) at 1-year.

CONCLUSIONS

In STEMI patients undergoing PPCI, advanced age (≥75 years) is associated with worse outcomes. The beneficial effects of EES over BMS tended to be age-dependent.

Impact of the Japan earthquake disaster with massive Tsunami on emergency coronary intervention and in-hospital mortality in patients with acute ST-elevation myocardial infarction

AIMS

The aims of this study were to evaluate reperfusion rate, therapeutic time course and in-hospital mortality pre- and post-Japan earthquake disaster, comparing patients with ST-elevation myocardial infarction (STEMI) treated in the inland area or the Tsunami-stricken area of Iwate prefecture.

METHOD AND RESULTS

Subjects were 386 consecutive STEMI patients admitted to the four percutaneous coronary intervention (PCI) centers in Iwate prefecture in 2010 and 2011. Patients were divided into two groups: those treated in the inland or Tsunami-stricken area. We compared clinical characteristics, time course and in-hospital mortality in both years in the two groups. PCI was performed in 310 patients (80.3%). Door-to-balloon (D2B) time in the Tsunami-stricken area in 2011 was significantly shorter than in 2010 in patients treated with PCI. However, the rate of PCI performed in the Tsunami-stricken area in March-April 2011 was significantly lower than that in March-April 2010 (41.2% vs 85.7%; p=0.03). In-hospital mortality increased three-fold from 7.1% in March-April 2010 to 23.5% in March-April 2011 in the Tsunami-stricken area. Standardized mortality ratio (SMR) in March-April 2011 in the Tsunami-stricken area was significantly higher than the control SMR (SMR 4.72: 95% confidence interval (CI): 1.77-12.6: p=0.007).

CONCLUSIONS

The rate of PCI decreased and in-hospital mortality increased immediately after the Japan earthquake disaster in the Tsunami-stricken area. Disorder in hospitals and in the distribution systems after the disaster impacted the clinical care and outcome of STEMI patients.

The use of drug-eluting stents in acute myocardial infarction - is the battle coming to an end? From despair to acceptance

The large-scale use of drug-eluting stents (DES) in elective percutaneous coronary interventions resulted in a significant reduction of restenosis and the need for repeat revascularization, compared to bare-metal stents (BMS) and balloon angioplasty. The position of DES used during primary percutaneous coronary intervention was not so well established. Based on the trials including the general population of patients, an increased risk of stent thrombosis was indicated, particularly late after implantation, which may be associated with increased mortality. A number of randomized clinical trials have compared first generation DES with BMS in acute ST-segment elevation myocardial infarction (STEMI). In most of them increased mortality after DES implantation was not confirmed, with demonstrated reduction of repeat revascularizations. However, long-term follow-up of these studies and the results from non-randomized “real world” registries are equivocal. A new generation of DES has been present on the market for several years. They have modern designs, are covered with more neutral polymers and release new drugs. The new generation DES have a better safety and efficacy profile, including a population of patients with acute STEMI, than the first generation stents. This paper is a review of randomized controlled trials, meta-analyses and registries, comparing DES with BMS in patients with acute STEMI. Attention was drawn to the current position and the role of new generation DES, which may prove to be a safe and effective choice in this population of patients.

Comparison of newer-generation drug-eluting with bare-metal stents in patients with acute ST-segment elevation myocardial infarction: a pooled analysis of the EXAMINATION (clinical Evaluation of the Xience-V stent in Acute Myocardial INfArcTION) and COMFORTABLE-AMI (Comparison of Biolimus Eluted From an Erodible Stent Coating With Bare Metal Stents in Acute ST-Elevation Myocardial Infarction) trials

OBJECTIVES

This study sought to study the efficacy and safety of newer-generation drug-eluting stents (DES) compared with bare-metal stents (BMS) in an appropriately powered population of patients with ST-segment elevation myocardial infarction (STEMI).

BACKGROUND

Among patients with STEMI, early generation DES improved efficacy but not safety compared with BMS. Newer-generation DES, everolimus-eluting stents, and biolimus A9-eluting stents, have been shown to improve clinical outcomes compared with early generation DES.

METHODS

Individual patient data for 2,665 STEMI patients enrolled in 2 large-scale randomized clinical trials comparing newer-generation DES with BMS were pooled: 1,326 patients received a newer-generation DES (everolimus-eluting stent or biolimus A9-eluting stent), whereas the remaining 1,329 patients received a BMS. Random-effects models were used to assess differences between the 2 groups for the device-oriented composite endpoint of cardiac death, target-vessel reinfarction, and target-lesion revascularization and the patient-oriented composite endpoint of all-cause death, any infarction, and any revascularization at 1 year.

RESULTS

Newer-generation DES substantially reduce the risk of the device-oriented composite endpoint compared with BMS at 1 year (relative risk [RR]: 0.58; 95% confidence interval [CI]: 0.43 to 0.79; p = 0.0004). Similarly, the risk of the patient-oriented composite endpoint was lower with newer-generation DES than BMS (RR: 0.78; 95% CI: 0.63 to 0.96; p = 0.02). Differences in favor of newer-generation DES were driven by both a lower risk of repeat revascularization of the target lesion (RR: 0.33; 95% CI: 0.20 to 0.52; p < 0.0001) and a lower risk of target-vessel infarction (RR: 0.36; 95% CI: 0.14 to 0.92; p = 0.03). Newer-generation DES also reduced the risk of definite stent thrombosis (RR: 0.35; 95% CI: 0.16 to 0.75; p = 0.006) compared with BMS.

CONCLUSIONS

Among patients with STEMI, newer-generation DES improve safety and efficacy compared with BMS throughout 1 year. It remains to be determined whether the differences in favor of newer-generation DES are sustained during long-term follow-up.

Stent thrombosis with drug-eluting stents: is the paradigm shifting?

First-generation drug-eluting stents (DES), which impart the controlled release of sirolimus or paclitaxel from durable polymers to the vessel wall, have been consistently shown to reduce the risk of restenosis and target vessel revascularization compared with bare metal stents (BMS). However, stent thrombosis (ST) emerged as a major safety concern with first-generation DES early after their adoption in clinical practice, requiring prolonged dual antiplatelet therapy. Pathological studies have shown that first-generation DES are associated with delayed arterial healing and polymer hypersensitivity reactions resulting in chronic inflammation, predisposing to late and very late ST. Second-generation DES have been developed to overcome these issues with improved stent designs and construction and the use of biocompatible and bioabsorbable polymers. Meta-analyses have shown that the thin-strut, fluoropolymer-coated cobalt-chromium everolimus-eluting stent (CoCr-EES) may be associated with lower rates of definite ST than other DES and, unexpectedly, even lower than BMS. The thin-strut structure of the stent platform, the thromboresistant properties of the fluoropolymer, and the reduced polymer and drug load may contribute to the low rate of ST with CoCr-EES. The notion of DES being safer than BMS represents a paradigm shift in the evolution of percutaneous coronary intervention. The relative safety and efficacy of fluoropolymer-coated CoCr-EES, DES with bioabsorbable polymers, and fully bioresorbable scaffolds are the subject of numerous ongoing large-scale trials.

Everolimus-eluting stent versus bare metal stent in proximal left anterior descending ST-elevation myocardial infarction: insights from the EXAMINATION trial

BACKGROUND

ST-elevation myocardial infarctions (STEMI) caused by proximal left-anterior descending (LAD) lesions have more myocardium at risk and worse outcomes than those located in other segments. The aim is to compare outcomes of patients with STEMI and proximal-LAD lesions treated with bare-metal stents (BMS) versus everolimus-eluting stents (EES).

METHODS

The EXAMINATION trial randomized 1498 STEMI patients to BMS versus EES. The primary end point was the patient-oriented combined of all-cause death, any-recurrent myocardial infarction (MI) and any-revascularization. The secondary end point included the device-oriented combined of cardiac death, target-vessel MI and target-lesion revascularization (TLR).

RESULTS

STEMI with a proximal-LAD occlusion was observed in 290 patients (BMS = 132 and EES = 158). Both groups were similar except for diabetes (12.9% vs 24.1%; P = .016). At 1 year, the primary end point was observed in 18.9% and 9.5% of patients treated with BMS and EES, respectively (P = .023). The secondary end point was observed in 11.4% and 5.1%, respectively (P = .053). There were no differences in cardiac death (4.5% vs 3.8%; P = .750) and MI (1.5% vs 0%; P = .121). BMS had higher rate of TLR compared to EES (6.8% vs 1.3%; P = .014). Patients with proximal-LAD STEMI had higher mortality than patients with non proximal-LAD STEMI (5.5% vs 2.9%; P = .027). Proximal-LAD lesions treated with BMS tended to increase the risk of the primary end point compared with other segments (18.9% vs 13.0%; P = .079). However, EES implanted in proximal-LAD had similar outcomes compared with other locations (9.5% vs 12.0%; P = .430). Adjusting for confounders, the interaction between BMS and proximal-LAD location was associated with the primary end point.

CONCLUSION

Patients with STEMI and proximal-LAD lesions treated with EES have better outcomes compared with BMS at 1 year. Although further investigations are required, it seems reasonable to consider EES for proximal-LAD STEMI-lesions.

Everolimus-eluting stent versus bare-metal stent in ST-segment elevation myocardial infarction (EXAMINATION): 1 year results of a randomised controlled trial

BACKGROUND

Everolimus-eluting stent (EES) reduces the risk of restenosis in elective percutaneous coronary intervention. However, the use of drug-eluting stent in patients with ST-segment elevation myocardial infarction (STEMI) is still controversial. Data regarding the performance of second-generation EES in this setting are scarce. We report the 1-year result of the EXAMINATION (clinical Evaluation of the Xience-V stent in Acute Myocardial INfArcTION) trial, comparing EES with bare-metal stents (BMS) in patients with STEMI.

METHODS

This multicentre, prospective, randomised, all-comer controlled trial was done in 12 medical centres in three countries. Between Dec 31, 2008, and May 15, 2010, we recruited patients with STEMI up to 48 h after the onset of symptoms requiring emergent percutaneous coronary intervention. Patients were randomly assigned (ratio 1:1) to receive EES or BMS. Randomisation was in blocks of four or six patients, stratified by centre and centralised by telephone. Patients were masked to treatment. The primary endpoint was the patient-oriented combined endpoint of all-cause death, any recurrent myocardial infarction, and any revascularisation at 1 year and was analysed by intention to treat. The secondary endpoints of the study included the device-oriented combined endpoint of cardiac death, target vessel myocardial infarction or target lesion revascularisation, and rates of all cause or cardiac death, recurrent myocardial infarction, target lesion or target vessel revascularisation, stent thrombosis, device and procedure success, and major and minor bleeding. This trial is registered with ClinicalTrials.gov, number NCT00828087.

FINDINGS

Of the 1504 patients randomised, 1498 patients were randomly assigned to receive EES (n=751) or BMS (n=747). The primary endpoint was similar in both groups (89 [11·9%] of 751 patients in the EES group vs 106 [14·2%] of 747 patients in the BMS group; difference -2·34 [95% CI -5·75 to 1·07]; p=0·19). Device-oriented endpoint (44 [5·9%] in the EES group vs 63 [8·4%] in the BMS group; difference -2·57 [95% CI -5·18 to 0·03]; p=0·05) did not differ between groups, although rates of target lesion and vessel revascularisation were significantly lower in the EES group (16 [2·1%] vs 37 [5·0%], p=0·003, and 28 [3·7%] vs 51 [6·8%], p=0·0077, respectively). Rates of all cause (26 [3·5%] for EES vs 26 [3·5%] for BMS, p=1·00) or cardiac death (24 [3·2%] for EES vs 21 [2·8%] for BMS, p=0·76) or myocardial infarction (10 [1·3%] vs 15 [2·0%], p=0·32) did not differ between groups. Stent thrombosis rates were significantly lower in the EES group (4 [0·5%] patients with definite stent thrombosis in the EES group vs 14 [1·9%] in the BMS group and seven [0·9%] patients with definite or probable stent thrombosis in the EES group vs 19 [2·5%] in the BMS group, both p=0·019). Although device success rate was similar between groups, procedure success rate was significantly higher in the EES group (731 [97·5%] vs 705 [94·6%]; p=0·0050). Finally, Bleeding rates at 1 year were comparable between groups (29 [3·9%] patients in the EES group vs 39 [5·2%] in the BMS group; p=0·19).

INTERPRETATION

The use of EES compared with BMS in the setting of STEMI did not lower the patient-oriented endpoint. However, at the stent level both rates of target lesion revascularisation and stent thrombosis were reduced in recipients of EES.

FUNDING

Spanish Heart Foundation.

Comparison of biolimus eluted from an erodible stent coating with bare metal stents in acute ST-elevation myocardial infarction (COMFORTABLE AMI trial): rationale and design

AIMS

Compared with bare metal stents (BMS), early generation drug-eluting stents (DES) reduce the risk of revascularisation in patients with ST-elevation myocardial infarction (STEMI) at the expense of an increased risk of very late stent thrombosis (ST). Durable polymer coatings for controlled drug release have been identified as a potential trigger for these late adverse events and this has led to the development of newer generation DES with durable and biodegradable polymer surface coatings with improved biocompatibility. In a recent all-comers trial, biolimus-eluting stents with a biodegradable polymer surface coating were found to reduce the risk of very late ST by 80% compared with sirolimus-eluting stents with durable polymer, which also translated into a lower risk of cardiac death and myocardial infarction (MI) beyond one year.

METHODS AND RESULTS

The multicentre COMFORTABLE AMI trial (NCT00962416) randomly assigned 1,161 patients to treatment with biolimus-eluting stents with biodegrable polymer and bare metal stents of otherwise identical design at 11 international sites. The primary endpoint is a composite of cardiac death, target-vessel MI and target lesion revascularisation at one year. Assuming a relative risk reduction of 40% in event rates of the primary endpoint in favour of biolimus-eluting stents with biodegradable polymer, 1,064 patients will provide 80% power to demonstrate superiority. Clinical follow-up will be continued through five years.

CONCLUSIONS

The COMFORTABLE AMI trial will determine whether biolimus-eluting stents with biodegradable polymer are superior to bare metal stents of otherwise identical design. This is the first randomised controlled trial (RCT) investigating DES with a biodegradable polymer surface coating for drug release in the treatment of patients with STEMI.