Ultrathin, bioresorbable polymer sirolimus-eluting stents versus thin, durable polymer everolimus-eluting stents in patients undergoing coronary revascularisation (BIOFLOW V): a randomised trial

Defining high bleeding risk in patients undergoing percutaneous coronary intervention: a consensus document from the Academic Research Consortium for High Bleeding Risk

Identification and management of patients at high bleeding risk undergoing percutaneous coronary intervention are of major importance, but a lack of standardization in defining this population limits trial design, data interpretation, and clinical decision-making. The Academic Research Consortium for High Bleeding Risk (ARC-HBR) is a collaboration among leading research organizations, regulatory authorities, and physician-scientists from the United States, Asia, and Europe focusing on percutaneous coronary intervention-related bleeding. Two meetings of the 31-member consortium were held in Washington, DC, in April 2018 and in Paris, France, in October 2018. These meetings were organized by the Cardiovascular European Research Center on behalf of the ARC-HBR group and included representatives of the US Food and Drug Administration and the Japanese Pharmaceuticals and Medical Devices Agency, as well as observers from the pharmaceutical and medical device industries. A consensus definition of patients at high bleeding risk was developed that was based on review of the available evidence. The definition is intended to provide consistency in defining this population for clinical trials and to complement clinical decision-making and regulatory review. The proposed ARC-HBR consensus document represents the first pragmatic approach to a consistent definition of high bleeding risk in clinical trials evaluating the safety and effectiveness of devices and drug regimens for patients undergoing percutaneous coronary intervention.

Two-year clinical outcome of all-comers treated with three highly dissimilar contemporary coronary drug-eluting stents in the randomised BIO-RESORT trial

AIMS

The aim of the study was to evaluate the two-year clinical outcome of all-comer trial participants who were treated with two very different thin-strut biodegradable polymer versus thin-strut durable polymer drug-eluting stents (DES). Prolonged clinical outcome after discontinuation of dual antiplatelet therapy is of particular interest, given the highly dissimilar polymer types, amount, distribution, and degradation speed of both biodegradable polymer DES.

METHODS AND RESULTS

The BIO-RESORT trial (NCT01674803) randomly assigned 3,514 patients to treatment with biodegradable polymer SYNERGY everolimus-eluting stents (EES) or Orsiro sirolimus-eluting stents (SES), or durable polymer Resolute Integrity zotarolimus-eluting stents (ZES). At two-year follow-up (available in 98.8%), the rate of the primary composite endpoint target vessel failure (TVF) was 8.3% in ZES versus 6.8% in EES (p=0.19) and 6.6% in SES (p=0.12). Landmark analyses at one year revealed differences between SES and ZES in the rates of target lesion revascularisation and target lesion failure (0.6% vs. 1.5%, p=0.04, and 1.1% vs. 2.4%, p=0.02, respectively) as well as other composite secondary endpoints that reached statistical significance.

CONCLUSIONS

At two-year follow-up, there was no significant between-DES difference in the rates of the primary endpoint. Landmark analyses provided a signal that the use of SES versus ZES might reduce the risk of repeat revascularisation after one-year follow-up.

Safety and efficacy of polymer-free biolimus-eluting stents versus ultrathin stents in unprotected left main or coronary bifurcation: A propensity score analysis from the RAIN and CHANCE registries

OBJECTIVES

Evaluate safety and efficacy of polymer-free biolimus-eluting stents (PF-BESs) versus ultrathin stents in unprotected left main (ULM) or bifurcation.

BACKGROUND

PF-BESs due to reduced length of dual antiplatelet therapy (DAPT) are increasingly used. However, there are limited data about safety and efficacy for ULM or bifurcation.

METHODS

We selected all-patients treated for ULM or bifurcation from two multicenter real life registries (RAIN [NCT03544294] evaluating ultrathin stents, CHANCE [NCT03622203] appraising PF-BES). After propensity score with matching, the primary endpoint was major adverse cardiac events (MACE; a composite of all-cause death, myocardial infarction, target lesion revascularization [TLR], and stent thrombosis [ST]), while its components along with target vessel revascularization (TVR) secondary endpoints.

RESULTS

Three thousand and three patients treated with ultrathin stents and 446 with PF-BESs, resulting respectively in 562 and 281 after propensity score with matching (33 and 22%, respectively, with ULM disease). After 12 (8-20) months, rates of MACE were similar (9 vs. 8%, p = 0.56) without difference in TLR and ST (3.0 vs. 1.7%, p = .19 and 1.8 vs. 1.1%, p = .42). These results were consistent for ULM group (3 vs. 1.7% and 1.8 vs. 1.1%, p = .49 and .76), for non-ULM group (2.1 vs. 3.4%, p = .56 and 1.2 vs. 1.7%, p = .78) and for two-stent strategy (8.7 vs. 4.5% and 4.3 vs. 3.2%, p = .75 and .91). Among patients treated with 1 month of DAPT in both groups, those with ultrathin stents experienced higher rates of MACE related to all-cause death (22 vs. 12%, p = .04) with higher although not significant rates of ST (3 vs. 0%, p = .45).

CONCLUSIONS

PF-BES implanted on ULM or BiF offered freedom from TLR and ST comparable to ultrathin stents. PF-BESs patients assuming DAPT for 1 month experienced a lower despite not significant incidence of ST.

Long-Term Effect of Ultrathin-Strut Versus Thin-Strut Drug-Eluting Stents in Patients With Small Vessel Coronary Artery Disease Undergoing Percutaneous Coronary Intervention

Background:

Randomized trials evaluating the Orsiro biodegradable polymer sirolimus-eluting stent (BP-SES; 60 and 80 μm strut thickness for stent diameters ≤3 and >3 mm, respectively) did not stratify according to vessel size and failed to specify the impact of ultrathin-strut thickness on long-term clinical outcomes compared with durable polymer everolimus-eluting stents (DP-EES). We sought to assess the long-term effect of ultrathin-strut (60 μm) BP-SES versus thin-strut (81 μm) DP-EES on long-term outcomes in patients undergoing percutaneous coronary revascularization for small vessel disease.

Methods:

In a subgroup analysis of the randomized, multicenter, noninferiority BIOSCIENCE trial, patients with stable coronary artery disease or acute coronary syndrome randomly assigned to treatment with BP-SES or DP-EES were stratified according to vessel size (≤3 mm versus >3 mm) as a surrogate to compare patients treated with ultrathin-strut versus thin-strut drug-eluting stent. The primary end point was target lesion failure, a composite of cardiac death, target vessel myocardial infarction, and clinically indicated target lesion revascularization, within 5 years.

Results:

Among 2109 patients, 1234 (59%) were treated for small vessel disease. At 5 years, target lesion failure occurred in 124 patients (cumulative incidence, 22.3%) treated with ultrathin-strut BP-SES and 109 patients (18.3%) treated with thin-strut DP-EES (rate ratio, 1.22; 95% CI, 0.94–1.58; P =0.13). Cumulative incidences of cardiac death, target vessel myocardial infarction, and clinically indicated target lesion revascularization and definite stent thrombosis at 5 years were similar in patients treated with ultrathin-strut BP-SES and thin-strut DP-EES. After adjustment for potential confounders, there was no significant interaction between vessel size and treatment effect of BP-SES versus DP-EES.

Conclusions:

We found no significant difference in clinical outcomes throughout 5 years between patients with small vessel disease treated with ultrathin-strut BP-SES versus thin-strut DP-EES.

Clinical Trial Registration:

URL: https://www.clinicaltrials.gov . Unique identifier: NCT01443104.

Outcomes of patients treated with ultrathin-strut biodegradable polymer sirolimus-eluting stents versus fluoropolymer-based everolimus-eluting stents: a meta-analysis of randomised trials

AIMS

The ultrathin-strut biodegradable polymer sirolimus-eluting stent (SES) is a new-generation drug-eluting stent (DES) developed to improve the percutaneous treatment of patients with coronary artery disease. Here, we sought to investigate whether the performance of the ultrathin-strut biodegradable polymer SES is superior to that of the benchmark thin-strut fluoropolymer-based everolimus-eluting stent (EES).

METHODS AND RESULTS

We undertook a study-level meta-analysis of trials in which patients receiving percutaneous coronary intervention (PCI) were randomly assigned to either SES or EES. Primary efficacy and safety outcomes were target lesion revascularisation (TLR) and definite/probable stent thrombosis (ST), respectively. Secondary outcomes were myocardial infarction (MI), death, target lesion failure (TLF) and target vessel failure (TVF). A total of 4,853 patients received a PCI with either SES (n=2,816) or EES (n=2,037) in six trials. After a weighted median follow-up of 12 months, patients treated with SES had a risk of TLR (odds ratio [95% confidence interval]: 1.24 [0.83-1.85], p=0.30), definite/probable ST (0.84 [0.53-1.33], p=0.45) and MI related to the target vessel (0.77 [0.55-1.07], p=0.12) comparable to that of patients treated with EES. We found no significant difference with regard to other secondary outcomes.

CONCLUSIONS

At one-year follow-up, the ultrathin-strut biodegradable polymer sirolimus-eluting stent displays a performance comparable to that of the fluoropolymer-based everolimus-eluting stent.

Defining High Bleeding Risk in Patients Undergoing Percutaneous Coronary Intervention

Identification and management of patients at high bleeding risk undergoing percutaneous coronary intervention are of major importance, but a lack of standardization in defining this population limits trial design, data interpretation, and clinical decision-making. The Academic Research Consortium for High Bleeding Risk (ARC-HBR) is a collaboration among leading research organizations, regulatory authorities, and physician-scientists from the United States, Asia, and Europe focusing on percutaneous coronary intervention-related bleeding. Two meetings of the 31-member consortium were held in Washington, DC, in April 2018 and in Paris, France, in October 2018. These meetings were organized by the Cardiovascular European Research Center on behalf of the ARC-HBR group and included representatives of the US Food and Drug Administration and the Japanese Pharmaceuticals and Medical Devices Agency, as well as observers from the pharmaceutical and medical device industries. A consensus definition of patients at high bleeding risk was developed that was based on review of the available evidence. The definition is intended to provide consistency in defining this population for clinical trials and to complement clinical decision-making and regulatory review. The proposed ARC-HBR consensus document represents the first pragmatic approach to a consistent definition of high bleeding risk in clinical trials evaluating the safety and effectiveness of devices and drug regimens for patients undergoing percutaneous coronary intervention.

Orsiro: ultrathin bioabsorbable polymer sirolimus-eluting stent

Recent stent developments aimed to reduce and eliminate the long-term inflammatory response include thinner struts, modifications to stent design and the development of bioresorbable polymers (BP). We aimed to summarize the main findings and to discuss the established and the potential benefits of the Orsiro BP sirolimus-eluting stents in everyday clinical use. We have reviewed the available evidence on the clinical performance of the Orsiro BP drug-eluting stents. Orsiro BP sirolimus-eluting stents is clinically proven and showed noninferiority against major drug-eluting stents and provides high safety and efficacy profile at long-term follow-up. Furthermore, it may be the preferred treatment option in specific subgroups as acute coronary syndrome, as shown in the BIOFLOW V trial.

Comparison of the polymer-free biolimus-coated BioFreedom stent with the thin-strut biodegradable polymer sirolimus-eluting Orsiro stent in an all-comers population treated with percutaneous coronary intervention: Rationale and design of the randomized SORT OUT IX trial

BACKGROUND

In patients with increased bleeding risk during dual antiplatelet therapy, the biolimus A9-coated BioFreedom, a stainless steel drug-coated stent devoid of polymer, has shown superiority compared to a bare-metal stent. The aim of this study was to investigate whether the polymer-free biolimus A9-coated BioFreedom is noninferior to a modern thin-strut biodegradable polymer cobalt-chromium sirolimus-eluting Orsiro stent in an all-comers patient population treated with percutaneous coronary intervention.

METHODS

The multicenter SORT OUT IX trial (NCT02623140) randomly assigned all-comers patients to treatment with the BioFreedom drug-coated stent or the biodegradable polymer Orsiro stent in 4 Danish University Hospitals. The primary end point target lesion failure is a composite of cardiac death, myocardial infarction (not related to other than index lesion), or target lesion revascularization within 12 months. Clinically driven event detection based on Danish registries will be used and continue through 5 years. Assuming an event rate of 4.2% in each stent group, 1,563 patients in each treatment arm will provide 90% power to detect noninferiority of the drug-coated BioFreedom stent with a noninferiority margin of 2.1%.

RESULTS

A total of 3,150 patients have been randomized and enrolled in the study.

CONCLUSIONS

The SORT OUT IX trial will determine whether the drug-coated BioFreedom stent is noninferior to a modern biodegradable polymer Orsiro stent.

High Bleeding Risk Patients Treated with Very Thin-Strut Biodegradable Polymer or Thin-Strut Durable Polymer Drug-Eluting Stents in the BIO-RESORT Trial

Purpose

Patients with high bleeding risk (HBR) who undergo percutaneous coronary intervention also have an increased risk of ischemic events and represent an overall high-risk population. The coating of durable polymer drug-eluting stents (DP-DES) may induce inflammation and delay arterial healing, which might be reduced by novel biodegradable polymer DES (BP-DES). We aimed to evaluate the safety and efficacy of treating HBR patients with very thin-strut BP-DES versus thin-strut DP-DES.

Methods

Participants in BIO-RESORT (NCT01674803), an investigator-initiated multicenter, randomized all-comers trial, were treated with very thin-strut BP-DES (Synergy or Orsiro) or thin-strut DP-DES (Resolute Integrity). For the present analysis, patients were classified following HBR criteria based on previous trials. The primary endpoint was target vessel failure: a composite of cardiac death, target vessel-related myocardial infarction, or target vessel revascularization at 1 year.

Results

Of all 3514 patients, 1009 (28.7%) had HBR. HBR patients were older (p < 0.001) and had more co-morbidities than non-HBR patients (p < 0.001). At 1-year follow-up, HBR patients had significantly higher rates of target vessel failure (6.7 vs. 4.2%, p = 0.003), cardiac death (1.9 vs. 0.4%, p < 0.001), and major bleeding (3.3 vs. 1.5%, p = 0.001). Of all 1009 HBR patients, 673 (66.7%) received BP-DES and 336 (33.3%) had DP-DES. The primary endpoint was met by 43/673 (6.5%) patients treated with BP-DES and 24/336 (7.3%) treated with DP-DES (HR 0.88 [95%CI 0.54–1.46], p = 0.63). There were no significant between-group differences in the most global patient-oriented clinical endpoint (9.7 vs. 10.5%, HR 0.92 [95%CI 0.61–1.39], p = 0.69) and other secondary endpoints.

Conclusions

At 1-year follow-up, very thin-strut BP-DES showed similar safety and efficacy for treating HBR patients as thin-strut DP-DES.

Electronic supplementary material

The online version of this article (10.1007/s10557-018-6823-9) contains supplementary material, which is available to authorized users.

[Comparative results of using coronary drug-eluting stents 'NanoMed' and Orsiro]

The purpose of the present study was to compare mid-term results of using drug-eluting stents 'NanoMed' and Orsiro. Within the framework of an ongoing randomized prospective study we carried out an intermediate analysis of clinical and angiographic data of 520 patients after coronary artery stenting. The duration of the follow-up period amounted to 6.8±0.2 months. The patients were randomly assigned to the study and control groups each consisting of 260 patients with implanted stents 'NanoMed' and Orsiro, respectively. The obtained findings demonstrated that the main baseline clinical, demographic, and angiographic parameters had no statistically significant differences. The primary endpoint was achieved in 6.1 and 5.3% of cases in the study and control group, respectively (p=0.7). One case of acute in-stent thrombosis was revealed in each group. Cardiac mortality amounted to 0.7% and 0.3% in the study and control group, respectively (p>0.9). Repeat interventions on the target lesion were performed in 2.7 versus 3.4% of cases in the study and control group, respectively (p=0.6). Hence, the comparative analysis of using 'NanoMed' and Orsiro stents in the mid-term period revealed no statistically significant differences.

Randomized evaluation of ticagrelor monotherapy after 3-month dual-antiplatelet therapy in patients with acute coronary syndrome treated with new-generation sirolimus-eluting stents: TICO trial rationale and design

BACKGROUND

Ticagrelor monotherapy after short-term dual-antiplatelet therapy (DAPT) may optimize ischemic and bleeding risks, particularly for acute coronary syndrome (ACS) patients, because its strategy is less potent than ticagrelor-based DAPT but more potent than aspirin or clopidogrel monotherapy.

METHODS

The TICO randomized open-label trial will evaluate whether ticagrelor monotherapy following 3-month DAPT is superior to 12-month ticagrelor-based DAPT in terms of net adverse clinical events (NACE) including efficacy and safety in ACS patients treated with ultrathin bioresorbable polymer sirolimus-eluting stents (BP-SES). Patients undergoing BP-SES implantation for ACS treatment will be randomized in a 1:1 fashion to the (1) ticagrelor monotherapy group after 3-month DAPT; or the (2) 12-month DAPT group. The primary endpoint is NACE within 12 months of percutaneous coronary intervention, which includes major adverse cardiac and cerebrovascular events (MACCE) plus major bleeding as defined by Thrombolysis in Myocardial Infarction. MACCE includes the composite of all-cause death, myocardial infarction, stent thrombosis, stroke, and target vessel revascularization. Secondary endpoints included each component of the primary endpoint.

CONCLUSIONS

The TICO trial is an ongoing trial evaluating the efficacy and safety of ticagrelor monotherapy following 3-month DAPT exclusively in ACS patients treated with uniform BP-SES. It may provide novel insights regarding the need for adjusted use of DAPT for rebalancing risk-benefit in current practice and changing from the conventional concept of aspirin maintenance to a ticagrelor-based regimen in the management of ACS.

Two-year safety evaluation of a biodegradable polymer sirolimus-eluting stent with increased drug elution and polymer absorption kinetics in complex patient and lesion cohort

OBJECTIVES

The aim of the present report was to compare 2-year safety outcomes of two biodegradable polymer (BP) sirolimus-eluting stents (SESs) with different drug eluting and polymer absorption kinetics in a subgroup of complex patients and lesions.

BACKGROUND

The previously published PANDA III study showed the BuMA BP SES, with faster drug elution and polymer absorption, was non-inferior to the Excel SES in target lesion failure (TLF).

METHODS

In PANDA III trial, patients who fulfilled one or more of the following criteria were included: Small vessel disease (reference vessel diameter ≤ 2.5 mm); long lesion (lesion length ≥ 20 mm); chronic total occlusion lesion; and diabetic patients.

RESULTS

Among 2,348 patients randomly assigned to treatment with BuMA (n = 1,174) or Excel SES (n = 1,174) in the PANDA III study, 858 in the BuMA group and 855 in the Excel group satisfied the inclusion criteria. At 2-year follow-up, the incidence of definite/probable stent thrombosis (ST) was significantly lower with BuMA SES as compared with Excel SES (0.7% vs. 1.9%, p = 0.03). This difference was mainly caused by decreased subacute stent thrombosis rate (0% vs. 0.6%, p = 0.03). In patients who did not fulfill the complex patient and lesion criteria, there were no between-group difference in ST (0.7% vs. 0%, p = 0.50). Myocardial infarction and TLF rates were similar (5.7% vs. 6.0%, p = 0.79 and 8.8% vs. 7.5%, p = 0.34, respectively), whereas patient-oriented composite endpoint was higher with BuMA SES mainly due to high risk of revascularization (15.6% vs. 11.4%, p = 0.01; 8.4% vs. 4.6%, p < 0.01).

CONCLUSIONS

Two-year subgroup analysis of the all-comer PANDA III trial revealed the increased safety benefit of the BuMA SES is more prominently seen in complex patient and lesion population.

CLINICAL TRIAL

ClinicalTrial.gov, Identifier-NCT02017275.

Most Promising Therapies in Interventional Cardiology

PURPOSE OF REVIEW

The last 40 years of clinical research in interventional cardiology were extraordinarily innovative. This article will review the most promising up and coming interventional cardiovascular therapies, with a primary focus on the treatment of coronary artery disease.

RECENT FINDINGS

From the first stent, to the first transcatheter aortic valve implantation (TAVI), and the left appendage closure technique, percutaneous interventions revolutionized the treatment of multiple diseases and dramatically improved the prognosis of many patients. While these advances have decreased the risk of mortality in some patients (such as ST-elevation myocardial infarction), 15% of acute coronary syndrome (ACS) patients still experience recurrent ischemic events within the first year, challenging us to develop new pharmaceutical targets and new devices. The continued emergence of data supporting inflammation as a risk factor and pharmacologic target as well as data supporting the importance of cholesterol efflux have identified novel therapeutic targets that may play a major role in the improvement of prognosis of patients with coronary artery disease. In addition, novel medical devices are being developed to allow even earlier detection of acute cardiac events and to support high-risk percutaneous coronary interventions. Advances in computing and the ability to analyze large datasets will allow us to use artificial intelligence to augment the clinician patient experience, both in and out of the catheterization laboratory, with live procedural guidance as well as pre- and post-operative prognostication tools.

Safety and efficacy of a sirolimus-eluting coronary stent with ultra-thin strut for treatment of atherosclerotic lesions (TALENT): a prospective multicentre randomised controlled trial

BACKGROUND

Supraflex is a sirolimus-eluting stent with a biodegradable polymer coating and ultra-thin struts. We aimed to compare Supraflex with the standard of care, Xience, an everolimus-eluting stent with a durable polymer coating, regarding clinical outcomes with a randomised trial in an all-comer population.

METHODS

We did a prospective, randomised, single-blind, multicentre study (TALENT) across 23 centres in Europe (the Netherlands, Poland, the UK, Spain, Bulgaria, Hungary, and Italy). Eligible participants were aged 18 years or older, had one or more coronary artery stenosis of 50% or greater in a native coronary artery, saphenous venous graft, or arterial bypass conduit, and had a reference vessel diameter of 2·25-4·50 mm. Patients underwent percutaneous coronary intervention in an all-comer manner. We randomly assigned patients (1:1) to implantation of either a sirolimus-eluting stent with a biodegradable polymer coating and ultra-thin struts (Supraflex) or an everolimus-eluting stent with a durable polymer coating (Xience). Randomisation was done by local investigators by use of a web-based software with random blocks according to centre. The primary endpoint was a non-inferiority comparison of a device-oriented composite endpoint-cardiac death, target-vessel myocardial infarction, or clinically indicated target lesion revascularisation-between groups at 12 months after the procedure, assessed in an intention-to-treat population. On assumption of 1-year composite endpoint prevalence of 8·3%, a margin of 4·0% was defined for non-inferiority of the Supraflex group compared with the Xience group. This trial is registered with ClinicalTrials.gov, number NCT02870140.

FINDINGS

Between Oct 21, 2016, and July 3, 2017, 1435 patients with 1046 lesions were randomly assigned to Supraflex, of whom 720 received the index procedure, and 715 patients with 1030 lesions were assigned to Xience, all receiving the index procedure. At 12 months, the primary endpoint had occurred in 35 patients (4·9 %) in the Supraflex group and in 37 patients (5·3%) in the Xience group (absolute difference -0·3% [one-sided 95% upper confidence bound 1·6%], p_{non-inferiority}<0·0001). Definite or probable stent thrombosis prevalence, a safety indicator, was low in both groups and did not differ between them.

INTERPRETATION

The Supraflex stent was non-inferior to the Xience stent for a device-oriented composite clinical endpoint at 12 months in an all-comer population. Supraflex seems a safe and effective alternative drug-eluting stent to other stents in clinical practice.

FUNDING

European Cardiovascular Research Institute.

Newer-generation Metallic Stents: Design, Performance Characteristics, and Outcomes

Several new coronary stents have been, or soon will be, introduced in the United States. These stents incorporate certain characteristics, such as polymer-free drug coatings, ultrathin stent struts, bioresorbable polymers, and composite materials, that address currently unmet clinical needs to enhance acute stent performance, improve longer-term clinical outcomes, and obviate obligatory prolonged dual antiplatelet therapy. This article reviews the key and novel features of these stents.

Biodegradable Zwitterionic Polymer Coatings for Magnesium Alloy Stents

Degradable metallic stents, most commonly composed of Mg-based alloys, are of interest as an alternative to traditional metallic stents for application in cardiac and peripheral vasculature. Two major design challenges with such stents are control of the corrosion rate and acute presentation of a nonthrombogenic surface to passing blood. In this study, several types of sulfobetaine (SB)-bearing biodegradable polyurethanes were developed and assessed as physical, chemical, and combination-type coatings for a model degradable Mg alloy, AZ31. For physical coatings, poly(ester sulfobetaine)urethane ureas, PESBUUs were synthesized using variable monomers that allowed the incorporation of a varying extent of carboxyl groups. Introduction of the carboxyl groups was associated with faster polymer degradation time. Simple physical coating of PESBUUs reduced macro- and microscopic thrombogenic deposition together with good stability of the coating attachment compared to a control coating of polylactic- co-glycolic acid. For PESBUUs incorporating carboxyl groups (PESBUUs-COOH), these groups could be converted to siloxane groups (PESBUUs-Si), thus creating polymers that could be surface reacted with the oxidized or phytic acid treated AZ31 surface. Chemical (silanization) attachment of these polymers reduced underlying alloy corrosion rates, but following the salination reaction with physical coating most reduced corrosion rates and protected the surface better from the consequences of oxidation occurring under the coating, such as blistering. The application of a multilayered coating approach using a sulfobetaine-based biodegradable elastomer thus offers options for degradable metallic stent design where thromboresistance is desired in combination with a means to control both polymeric coating degradation rates and underlying alloy corrosion rates.

Feasibility of a Porcine Arteriovenous Shunt Model for Assessment of Acute Thrombogenicity in Bifurcation Stenting Technique By Optical Coherence Tomography

BACKGROUND

Double kissing (DK) crush stenting has been reported as a superior bifurcation stenting strategy compared to culotte stenting. However, the mechanism associated with the reduction of clinical events by DK crush stenting remains unclear. We therefore investigated the thrombogenicity of DK crush stenting and culotte stenting with both bare-metal stents (BMS) and drug-eluting stents (DES) and the feasibility of a novel porcine arteriovenous shunt model.

METHODS

High-resolution intracoronary imaging with optical coherence tomography (OCT) evaluated the bifurcation stenting models for thrombogenicity.

RESULTS

All porcine models retained continuous circulation without blood leakage. Thrombus was macroscopically demonstrated around the bifurcation in all settings. The volume of thrombus (mm³) with BMS using DK crush/culotte and DES using DK crush/culotte were 1.38/1.19 and 0.09/0.15, respectively. Culotte stenting had more thrombus in the proximal main branch, and DK crush stenting had more at the bifurcation. Unlike DK crush stenting, culotte stenting showed malapposition in the proximal main branch and bifurcation segments.

CONCLUSION

The feasibility of a porcine arteriovenous shunt model to assess thrombogenicity by OCT in bifurcation stenting technique was confirmed. OCT detected less thrombogenicity in DES when used in the bifurcation model when compared to BMS.

Cost-effectiveness analysis of short-duration dual antiplatelet therapy with newer drug-eluting stent platforms versus longer-duration dual antiplatelet therapy with a second-generation drug-eluting stent in elective percutaneous coronary intervention

BACKGROUND

The cost-effectiveness of newer drug-eluting stents (DES) such as biodegradable-polymer or polymer-free stents with shorter dual antiplatelet therapy (DAPT) duration is unknown. We evaluated the cost-effectiveness of treatment with newer DES that may allow for shorter DAPT duration.

PATIENTS AND METHODS

We performed a cost-effectiveness analysis of treatment with newer DES platforms followed by 1 or 3 months of DAPT compared with standard second-generation DES followed by 6 or 12 months of DAPT in patients with stable coronary disease. A Markov model simulated distinct health states over a lifetime. Probabilistic sensitivity analysis and one-way sensitivity analyses were performed. A high-risk bleeding scenario was also evaluated.

RESULTS

Among patients with typical bleeding risk, second-generation DES and 6 months of DAPT was less expensive and resulted in marginally higher quality-adjusted life years compared with other strategies. A newer DES platform and 3 months of DAPT was preferred when the risk of fatal bleeding was two times greater than baseline, or when bleeding increased long-term mortality by a factor of 1.5. In a probabilistic sensitivity analysis, second-generation DES and 6 months of DAPT was preferred in 58% of iterations, whereas in a high-risk bleeding patient scenario, a newer DES and 3 months of DAPT was preferred in 52% of iterations.

CONCLUSION

A DES that allows 3 months of DAPT without increasing stent-related events is likely to be cost-effective among patients at elevated risk of bleeding, but not in patients with average bleeding risk.

Thin and crush: The new mantra in left main stenting?

Complex bifurcations have been suggested to be better approached by a planned double stent technique; however, recent randomized trials have shown better outcomes of provisional compared to planned two-stent strategy, in terms of both short-term efficacy and safety. In left main (LM) bifurcations, double kissing (DK)-Crush has demonstrated its superiority over Culotte and provisional-T in terms of restenosis and stent thrombosis, gaining respect as one of the most performant techniques for bifurcations stenting. On the other hand, the Nano-Crush technique has recently become part of the repertoire of double stenting techniques, providing evidence that the use of ultrathin strut stents and very minimal crush would be beneficial for both the physiological and rheological properties of the complex bifurcations, even in LM scenario, leading to a lower rate of thrombosis and restenosis at both side branch and true carina. Finally, the newest generation of ultrathin strut stents are gaining a reputation for its safe and effective use in LM treatment thanks to improved design with increased expansion rate capable of LM treatment up to 5-6 mm diameter. The modern crush techniques, such as DK-Crush and Nano-Crush, are providing excellent results on mid and long-term follow up, suggesting that minimal crushing obtained using ultra-thin stents is a good way to obtain surgical-like outcomes in the treatment of complex LM bifurcation disease.

Biodegradable polymer versus second-generation durable polymer drug-eluting stents in patients with coronary artery disease: A meta-analysis

AIMS

Biodegradable polymer drug-eluting stents (BP-DES) were developed in hopes of reducing the risk of stent thrombosis. The comparison of this new stent platform with second-generation durable polymer drug-eluting stents (DP-DES) has not been well described. We, therefore, performed a meta-analysis to evaluate the safety and efficacy profiles of BP-DES versus second-generation DP-DES in patients with coronary artery disease.

METHODS AND RESULTS

Electronic database searches were conducted, from their dates of inception to June 2018, to identify randomized controlled trials (RCTs) comparing patients with either BP-DES or second-generation DP-DES. Risk estimates were expressed as risk ratios (RRs) with 95% confidence intervals (CIs). We also performed a landmark analysis beyond 1 year and sensitivity analyses based on different variables. A total of 24,406 patients from 19 RCTs were included in the present meta-analysis. There were no significant differences between BP-DES and second-generation DP-DES for the risks of definite or probable stent thrombosis (RR 0.88; 95% CI, 0.69-1.12; P = 0.29), myocardial infarction (RR 0.97; 95% CI, 0.86-1.09; P = 0.59), cardiac death (RR 1.08; 95% CI, 0.92-1.28; P = 0.34), all-cause death (RR 1.02; 95% CI, 0.91-1.13; P = 0.77), target lesion revascularization (RR 1.05; 95% CI, 0.94-1.17; P = 0.38), and target vessel revascularization (RR 1.05; 95% CI, 0.95-1.16; P = 0.36). Similar outcomes were observed regardless of anti-proliferative drug and duration of dual antiplatelet therapy (all P > 0.05).

CONCLUSION

Our findings demonstrate similar safety and efficacy profiles between BP-DES and second-generation BP-DES, with comparable rates of stent thrombosis.

Undiscovered pathology of transient scaffolding t1remains a driver of failures in clinical trials

AIM

To statistically examine the released clinical trials and meta-analyses of polymeric bioresorbable scaffolds resuming the main accomplishments in the field with a translation to the routine clinical practice.

METHODS

The statistical power in clinical trials such as ABSORB Japan, ABSORB China, EVERBIO II, AIDA, and few meta-analyses by the post hoc odds ratio-based sample size calculation, and the patterns of artery remodeling published in papers from ABSORB A and B trials were evaluated.

RESULTS

The phenomenal admiration from the first ABSORB studies in 2006-2013 was replaced by the tremendous disappointment in 2014-2017 due to reported relatively higher rates of target lesion failure (a mean prevalence of 9.16%) and device thrombosis (2.38%) in randomized controlled trials. Otherwise, bioresorbable vascular scaffold (BVS) performs as well as the metallic drug-eluting stent (DES) with a trend toward some benefits for cardiac mortality [risk ratio (RR), 0.58-0.94, P > 0.05]. The underpowered design was confirmed for some studies such as ABSORB Japan, ABSORB China, EVERBIO II, AIDA trials, and meta-analyses of Polimeni, Collet, and Mahmoud with some unintentional bias (judged by the asymmetrical Funnel plot). Scaffold thrombosis rates with Absorb BRS were comparable with DES performed with a so-called strategy of the BVS implantation with optimized pre-dilation (P), sizing (S) and post-dilation (P) (PSP) implantation (RR, PSP vs no PSP 0.37) achieving 0.35 per 100 patient-years, which is comparable to the RR 0.49 with bare-metal stents and the RR 1.06 with everolimus DES. Both ABSORB II and ABSORB III trials were powered enough for a five-year follow-up, but the results were not entirely conclusive due to the mostly non-significant fashion of data. The powered meta-analyses were built mostly on statistically poor findings.

CONCLUSION

The misunderstanding of the pathology of transient scaffolding drives the failures of the clinical trials. More bench studies of the vascular response are required. Several next-generation BVS including multifunctional electronic scaffold grant cardiology with a huge promise to make BVS technology great again.

Thin composite wire strut, durable polymer-coated (Resolute Onyx) versus ultrathin cobalt-chromium strut, bioresorbable polymer-coated (Orsiro) drug-eluting stents in allcomers with coronary artery disease (BIONYX): an international, single-blind, randomised non-inferiority trial

BACKGROUND

During the past decade, many patients had zotarolimus-eluting stents implanted, which had circular shape cobalt-chromium struts with limited radiographic visibility. The Resolute Onyx stent was developed to improve visibility while reducing strut thickness, which was achieved by using a novel composite wire with a dense platinum-iridium core and an outer cobalt-chromium layer. We did the first randomised clinical trial to assess the safety and efficacy of this often-used stent compared with the Orsiro stent, which consists of ultrathin cobalt-chromium struts.

METHODS

We did an investigator-initiated, assessor-blinded and patient-blinded, randomised non-inferiority trial in an allcomers population at seven independently monitored centres in Belgium, Israel, and the Netherlands. Eligible participants were aged 18 years or older and required percutaneous coronary intervention with drug-eluting stents. After guide wire passage with or without predilation, members of the catheterisation laboratory team used web-based computer-generated allocation sequences to randomly assign patients (1:1) to either the Resolute Onyx or the Orsiro stent. Randomisation was stratified by sex and diabetes status. Patients and assessors were masked to allocated stents, but treating clinicians were not. The primary endpoint was target vessel failure at 1 year, a composite of cardiac death, target-vessel-related myocardial infarction, and target vessel revascularisation, and was assessed by intention to treat (non-inferiority margin 2·5%) on the basis of outcomes adjudicated by an independent event committee. This trial is registered with ClinicalTrials.gov, number NCT02508714.

FINDINGS

Between Oct 7, 2015, and Dec 23, 2016, 2516 patients were enrolled, 2488 of whom were included in the intention-to-treat analysis (28 withdrawals or screening failures). 1243 participants were assigned to the Resolute Onyx group, and 1245 to the Orsiro group. Overall, 1765 (70·9%) participants presented with acute coronary syndromes and 1275 (51·2%) had myocardial infarctions. 1-year follow-up was available for 2478 (99·6%) patients. The primary endpoint was met by 55 (4·5%) patients in the Resolute Onyx group and 58 (4·7%) in the Orsiro group. Non-inferiority of Resolute Onyx to Orsiro was thus established (absolute risk difference -0·2% [95% CI -1·9 to 1·4]; upper limit of the one-sided 95% CI 1·1%; p_{non-inferiority}=0·0005). Definite or probable stent thrombosis occurred in one (0·1%) participant in the Resolute Onyx group and nine (0·7%) in the Orsiro group (hazard ratio 0·11 [95% CI 0·01-0·87]; p=0·0112).

INTERPRETATION

The Resolute Onyx stent was non-inferior to Orsiro for a combined safety and efficacy endpoint at 1-year follow-up in allcomers. The low event rate in both groups suggests that both stents are safe, and the very low rate of stent thrombosis in the Resolute Onyx group warrants further clinical investigation.

FUNDING

Biotronik and Medtronic.

Targeted therapy with a localised abluminal groove, low-dose sirolimus-eluting, biodegradable polymer coronary stent (TARGET All Comers): a multicentre, open-label, randomised non-inferiority trial

BACKGROUND

The FIREHAWK is a drug-eluting stent with a fully biodegradable sirolimus-containing polymer coating localised to recessed abluminal grooves on the stent surface. We investigated clinical outcomes with this targeted, low-dose, biodegradable polymer, sirolimus-eluting stent compared with XIENCE durable polymer, everolimus-eluting stents in an all-comers population.

METHODS

The TARGET All Comers study was a prospective, multicentre, open-label randomised non-inferiority trial done at 21 centres in ten European countries. Patients with symptomatic or asymptomatic coronary artery disease and objective evidence of myocardial ischaemia who qualified for percutaneous coronary intervention were randomised 1:1 to undergo implantation of a FIREHAWK or XIENCE. Randomisation was web-based, with random block allocation and stratification by centre and ST elevation myocardial infarction. Outcome assessors were masked to treatment allocation, but treating physicians and patients were not. The primary endpoint was target lesion failure at 12 months, a composite of cardiac death, target vessel myocardial infarction, or ischaemia-driven target lesion revascularisation. The control event rate for XIENCE was assumed to be 7%, the non-inferiority margin was 3.5%, and the primary analysis was in the intention-to-treat population, censoring patients who did not have either an event before 365 days or contact beyond 365 days. Late lumen loss was the primary endpoint of an angiographic substudy designed to investigate the non-inferiority of the FIREHAWK compared with the XIENCE stent. This trial is registered with ClinicalTrials.gov, number NCT02520180.

FINDINGS

From Dec 17, 2015, to Oct 14, 2016, 1653 patients were randomly assigned to implantation of the FIREHAWK (n=823) or XIENCE (n=830). 65 patients in the FIREHAWK group and 66 in the XIENCE group had insufficient follow-up data and were excluded from the analyses. At 12 months, target lesion failure occurred in 46 (6·1%) of 758 patients in the FIREHAWK group and in 45 (5·9%) of 764 patients in the XIENCE group (difference 0·2%, 90% CI -1·9 to 2·2, p_{non-inferiority}=0·004, 95% CI -2·2 to 2·6, p_superiority=0·88). There were no differences in ischaemia-driven revascularisation or stent thrombosis rates at 12 months. 176 patients were included in the angiographic substudy, in which in-stent late lumen loss was 0·17 mm (SD 0·48) in the FIREHAWK group and 0·11 mm (0·52) in the XIENCE group (p=0·48), with an absolute difference of 0·05 mm (95% CI -0·09 to 0·18, p_{non-inferiority}=0·024).

INTERPRETATION

In a broad all-comers population of patients requiring stent implantation for myocardial ischaemia, the FIREHAWK was non-inferior to the XIENCE as assessed with the primary endpoint of target lesion failure at 12 months and in-stent late lumen loss at 13 months. The FIREHAWK is a safe and effective alternative stent to treat patients with ischaemic coronary artery disease in clinical practice.

FUNDING

Shanghai Microport Medical.

Ultrathin-strut, biodegradable-polymer, sirolimus-eluting stents versus thin-strut, durable-polymer, everolimus-eluting stents for percutaneous coronary revascularisation: 5-year outcomes of the BIOSCIENCE randomised trial

BACKGROUND

Drug-eluting stents combining an ultrathin cobalt-chromium stent platform with a biodegradable polymer eluting sirolimus have been shown to be non-inferior or superior to thin-strut, durable-polymer, everolimus-eluting stents in terms of 1 year safety and efficacy outcomes.

METHODS

In the randomised, single-blind, multicentre, non-inferiority BIOSCIENCE trial, we compared biodegradable-polymer sirolimus-eluting stents with durable-polymer everolimus-eluting stents in patients with chronic stable coronary artery disease or acute coronary syndromes. Here, we assess the final 5-year clinical outcomes of BIOSCIENCE with regards to the primary clinical outcome of target lesion failure, which was a composite of cardiac death, target vessel myocardial infarction, and clinically indicated target lesion revascularisation. The primary analysis was done by intention to treat. The BIOSCIENCE trial is registered with ClinicalTrials.gov, number NCT01443104.

FINDINGS

2008 (95%) of 2119 patients recruited between March 1, 2012, and May 31, 2013, completed 5 years of follow-up. Target lesion failure occurred in 198 patients (cumulative incidence 20·2%) treated with biodegradable-polymer sirolimus-eluting stents and in 189 patients (18·8%) treated with durable-polymer everolimus-eluting stents (rate ratio [RR] 1·07, 95% CI 0·88-1·31; p=0·487). All-cause mortality was significantly higher in patients treated with biodegradable-polymer sirolimus-eluting stents than in those treated with durable-polymer everolimus-eluting stents (14·1% vs 10·3%; RR 1·36, 95% CI 1·06-1·75; p=0·017), driven by a difference in non-cardiovascular deaths. We observed no difference between groups in cumulative incidence of definite stent thrombosis at 5 years (1·6% in both groups; 1·02, 0·51-2·05; p=0·950).

INTERPRETATION

5-year risk of target lesion failure among all-comer patients undergoing percutaneous coronary intervention is similar after implantation of ultrathin-strut, biodegradable-polymer, sirolimus-eluting stents or thin-strut, durable-polymer, everolimus-eluting stents. Higher incidences of all-cause and non-cardiovascular mortality in patients treated with biodegradable-polymer stents eluting sirolimus than in those treated with durable-polymer stents eluting everolimus warrant careful observation in ongoing clinical trials.

FUNDING

Clinical Trials Unit of the University of Bern and Biotronik.