Stent Thrombosis With Drug-Eluting Stents and Bioresorbable Scaffolds

Long-Term Percutaneous Coronary Intervention Outcomes in Chronic Versus Acute Coronary Syndromes (TARGET All Comers Trial)

In the Targeted therapy with a localised abluminal coated, low-dose sirolimus-eluting, biodegreadable polymer coronary stent (TARGET; NCT02520180) All Comers trial the biodegradable polymer (BP) sirolimus-eluting FIREHAWK stent was noninferior to the durable polymer (DP) everolimus-eluting XIENCE stent with respect to target lesion failure (TLF) at 1 and 5 years; however, the long-term safety and efficacy in the setting of acute coronary syndromes (ACS) are not known. We sought to assess the long-term outcomes in ACS versus chronic coronary syndromes (CCS) with BP sirolimus-eluting stent (SES) versus DP everolimus-eluting stent (EES). The TARGET AC study was a multicenter, open-label, noninferiority trial of all comer patients randomly allocated 1:1 to BP SES or DP EES (stratified by ST-elevation myocardial infarction and study site). In this predefined substudy, the outcomes were compared based on clinical presentation (ACS vs CCS) and treatment allocation. A total of 1,653 patients were enrolled (728 with ACS and 922 with CCS), with 94% completing the 5-year follow-up. The baseline characteristics were well-matched between the 2 stent types; however, co-morbidities were more prevalent in the CCS than in the ACS population. TLF (15.5% vs 17.7%, p = 0.24), patient-oriented outcomes (32.0% vs 34.4%, p = 0.31), and stent thrombosis (4.1% vs 3.3%, p = 0.40) were similar between patients with ACS and patients with CCS. In the ACS cohort, the outcomes at 5 years for BP SES versus DP EES were similar for TLF (16.0% vs 14.9%, p = 0.70), ischemia-driven target lesion revascularization (5.6% vs 8.3%, p = 0.17), and definite/probable stent thrombosis (2.7% vs 4.6%, p = 0.18). The same was true for the CCS cohort, with 5-year outcomes for BP SES versus DP EES for TLF (18.0% vs 17.4%, p = 0.82), ischemia-driven target lesion revascularization (6.4% vs 5.0%, p = 0.37), and definite/probable stent thrombosis (3.0% vs 1.8%, p = 0.26). In conclusion, in the TARGET AC trial, 1 in 3 patients had a major adverse event at 5 years, irrespective of CCS or ACS presentation. Long-term, the BP sirolimus-eluting FIREHAWK stent was as safe and effective as the DP everolimus-eluting XIENCE stent across the spectrum of clinical presentations.

A bio-inspired nanoparticle coating for vascular healing and immunomodulatory by cGMP-PKG and NF-kappa B signaling pathways

Drug-eluting stents (DESs) implantation is an effective method to tackle in-stent restenosis (ISR), which has been considered as an efficient treatment for coronary atherosclerosis. Although fruitful results have been achieved in treating coronary artery diseases (CAD), concern has arisen regarding the long-term safety and efficacy of DESs, primarily due to adverse events such as delayed re-endothelialization, persistent inflammatory response, and late stent thrombosis (LST). Taking inspiration from the immunomodulatory functions of camouflage strategies, this study designed a bio-inspired nanoparticle-coated stent. Briefly, the platelet membrane-coated poly (lactic-co-glycolic acid)/Rapamycin nanoparticles (PNP) were sprayed onto stents, forming a homogenous nanoparticle coating. The bilayer of poly (lactic-co-glycolic acid) (PLGA) and platelet membrane works synergistically to promote the sustained-release effect of rapamycin. In vitro studies revealed that the PNP-coated surfaces promoted the competitive adhesion of endothelia cells while inhibiting smooth muscle cells. Subsequent in vivo studies demonstrated that these surfaces expedite re-endothelialization and elicit immunomodulatory effects by regulating the cGMP-PKG and NF-kappa B signaling pathways, influencing the biosynthesis cofactors and immune system signaling. The study successfully deviced a novel and biomimetic drug-eluting stent system, unraveling its detailed functions and molecular mechanism of action for enhanced vascular healing.

The Usefulness of Intracoronary Imaging in Patients with ST-Segment Elevation Myocardial Infarction

Intracoronary imaging (ICI) modalities, namely intravascular ultrasound (IVUS) and optical coherence tomography (OCT), have shown to be able to reduce major adverse cardiovascular events in patients undergoing percutaneous coronary intervention (PCI). Nevertheless, patients with ST-segment elevation myocardial infarction (STEMI) have been practically excluded from contemporary large randomized controlled trials. The available data are limited and derive mostly from observational studies. Nevertheless, contemporary studies are in favor of ICI utilization in patients who undergo primary PCI. Regarding technical aspects of PCI, ICI has been associated with the implantation of larger stent diameters, higher balloon inflations and lower residual in-stent stenosis post-PCI. OCT, although used significantly less often than IVUS, is a useful tool in the context of myocardial infarction without obstructive coronary artery disease since, due to its high spatial resolution, it can identify the underlying mechanism of STEMI, and, thus, guide therapy. Stent thrombosis (ST) is a rare, albeit a potential lethal, complication that is expressed clinically as STEMI in the vast majority of cases. Use of ICI is encouraged with current guidelines in order to discriminate the mechanism of ST among stent malapposition, underexpansion, uncovered stent struts, edge dissections, ruptured neoatherosclerotic lesions and coronary evaginations. Finally, ICI has been proposed as a tool to facilitate stent deferring during primary PCI based on culprit lesion characteristics.

Benchtop proof of concept and comparison of iron- and magnesium-based bioresorbable flow diverters

OBJECTIVE

Bioresorbable flow diverters (BRFDs) could significantly improve the performance of next-generation flow diverter technology. In the current work, magnesium and iron alloy BRFDs were prototyped and compared in terms of porosity/pore density, radial strength, flow diversion functionality, and resorption kinetics to offer insights into selecting the best available bioresorbable metal candidate for the BRFD application.

METHODS

BRFDs were constructed with braided wires made from alloys of magnesium (MgBRFD) or iron (FeBRFD). Pore density and crush resistance force were measured using established methods. BRFDs were deployed in silicone aneurysm models attached to flow loops to investigate flow diversion functionality and resorption kinetics in a simulated physiological environment.

RESULTS

The FeBRFD exhibited higher pore density (9.9 vs 4.3 pores/mm2) and crush resistance force (0.69 ± 0.05 vs 0.53 ± 0.05 N/cm, p = 0.0765, n = 3 per group) than the MgBRFD, although both crush resistances were within the range previously reported for FDA-approved flow diverters. The FeBRFD demonstrated greater flow diversion functionality than the MgBRFD, with significantly higher values of established flow diversion metrics (mean transit time 159.6 ± 11.9 vs 110.9 ± 1.6, p = 0.015; inverse washout slope 192.5 ± 9.0 vs 116.5 ± 1.5, p = 0.001; n = 3 per group; both metrics expressed as a percentage of the control condition). Last, the FeBRFD was able to maintain its braided structure for > 12 weeks, whereas the MgBRFD was almost completely resorbed after 5 weeks.

CONCLUSIONS

The results of this study demonstrated the ability to manufacture BRFDs with magnesium and iron alloys. The data suggest that the iron alloy is the superior material candidate for the BRFD application due to its higher mechanical strength and lower resorption rate relative to the magnesium alloy.

Antiplatelet Therapy Aims and Strategies in Asian Patients with Acute Coronary Syndrome or Stable Coronary Artery Disease

Dual antiplatelet therapy (DAPT) has been the mainstay treatment to reduce ischemic events, such as myocardial infarction or stroke, in patients with coronary artery disease (CAD). The development of potent P2Y₁₂ inhibitors (ticagrelor and prasugrel) has helped to further reduce ischemic events, particularly among high-risk patients. Meanwhile, the evolution of newer generations of drug-eluting stents are also improving outcomes of percutaneous coronary intervention. Research studies on antiplatelet therapy in recent years have focused on balancing ischemic and bleeding risks through different strategies, which include P2Y₁₂ inhibitor monotherapy, escalation and de-escalation, and extended DAPT. Because results from the large number of clinical studies may sometimes appear conflicting, this review aims to summarize recent advances, and demonstrate that they are aligned by a general principle, namely, strategies may be adopted based on treatment aims for specific patients at several time points. Another aim of this review is to outline the important considerations for using antiplatelet therapy in Asian patients, in whom there is a greater prevalence of CYP2C19 loss-of-function mutations, and a common increased risk of bleeding, despite high platelet reactivity (the so-called "East Asian Paradox").

Clinical outcomes of percutaneous coronary intervention for de novo lesions in small coronary arteries: A systematic review and network meta-analysis

Background

Percutaneous coronary intervention (PCI) has a well-established role in revascularization for coronary artery disease. We performed network meta-analysis to provide evidence on optimal intervention strategies for de novo lesions in small coronary arteries.

Materials and methods

Enrolled studies were randomized clinical trials that compared different intervention strategies [balloon angioplasty (BA), biolimus-coated balloon (BCB), bare-metal stent (BMS), new-generation drug-eluting stent (New-DES), older generation sirolimus-eluting stent (Old-SES), paclitaxel-coated balloon (PCB), and paclitaxel-eluting stent (PES)] for de novo lesions in small coronary arteries. The primary outcome was major adverse cardiac events (MACE).

Results

A total of 23 randomized clinical trials comparing seven intervention devices were analyzed. In terms of the primary outcome, New-DES was the intervention device with the best efficacy [surface under the cumulative ranking curve (SUCRA), 89.1%; mean rank, 1.7], and the Old-SES [risk ratio (RR), 1.09; 95% confidence interval (CI), 0.45–2.64] and PCB (RR, 1.40; 95% CI, 0.72–2.74) secondary to New-DES, but there was no statistically significant difference between these three intervention devices. All DES and PCB were superior to BMS and BA for MACE in both primary and sensitivity analysis. For secondary outcomes, there was no association between all-cause mortality and myocardial infarction (MI) with any intervention strategy, and additionally, the findings of target lesion revascularization (TLR) were similar to the primary outcomes.

Conclusion

Paclitaxel-coated balloon yielded similar outcomes to New-DES for de novo lesions in small coronary arteries. Therefore, this network meta-analysis may provide potential support for PCB as a feasible, effective, and safe alternative intervention strategy for the revascularization of small coronary arteries.

Systematic review registration

[https://www.crd.york.ac.uk/PROSPERO/#recordDetails], identifier [CRD42022338433].

Coronary Stenting: Reflections on a 35-Year Journey

Stenting was introduced as a therapy for coronary artery disease 35 years ago, and is currently the most commonly performed minimally invasive procedure globally. Percutaneous coronary revascularization, initially with plain old balloon angioplasty and later with stenting, has dramatically affected the outcomes of acute myocardial infarction and acute coronary syndromes. Coronary stenting is probably the most intensively studied therapy in medicine on the basis of the number of randomized clinical trials for a broad range of indications. Continuous improvements in stent materials, design, and coatings concurrent with procedural innovations have truly been awe-inspiring. The story of stenting is replete with high points and some low points, such as the initial experience with stent thrombosis and restenosis, and the more recent disappointment with bioabsorbable scaffolds. History has shown rapid growth of stent use with expansion of indications followed by contraction of some uses in response to clinical trial evidence in support of bypass surgery or medical therapy. In this review we trace the constantly evolving story of the coronary stent from the earliest experience until the present time. Undoubtedly, future iterations of stent design and materials will continue to move the stent story forward.

Bioresorbable scaffolds vs. drug-eluting stents on short- and mid-term target lesion outcomes in patients after PCI: A systematic review and meta-analysis

Background

While current concerns about bioresorbable scaffolds (BRS) are centered on late or very late scaffold thrombosis, less attention had been paid to short- and mid-term clinical outcomes. This review aimed to compare the short- and mid-term outcomes between BRS and drug-eluting stents (DES).

Methods

A systematic review of randomized controlled trials (RCTs) that compared BRS vs. DES was conducted by searching PubMed, Cochrane Library, Web of Science, CNKI, WanFang, and VIP databases from inception until 19 April 2022 (language limited to English or Chinese). The primary outcome was target lesion failure (TLF) within 12 months, defined as a composite of target lesion revascularization (TLR), target vessel myocardial infarction (TVMI), and cardiac death. The secondary outcomes were in-stent diameter stenosis (DS%) provided by intraluminal imaging.

Results

A total of 13 studies were eligible and were included in this review (N = 9,702 patients). The follow-up duration ranged from 6 months to 1 year. A significantly higher rate of TLF [RR, 1.22, 95% CI (1.03, 1.44)] driven by the higher rate of TVMI [RR, 1.39, 95% CI (1.09, 1.76)] was observed in the BRS group than in the DES group. The risk of TLR and cardiac death was similar between the groups. Also, compared with the DES group, the BRS group had a significantly higher in-stent DS% within 1 year [MD = 5.23, 95%CI (3.43, 7.04); I² = 97%; p < 0.00001].

Conclusion

Bioresorbable scaffolds were associated with an increased risk of target lesion failure within 1 year as compared with DES, driven by the increased rates of target vessel myocardial infarction. Also, the in-stent DS% seemed to be higher with BRS. Therefore, BRS was inferior to DES in terms of target lesion outcomes at short- or mid-term follow-up.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=327966, PROSPERO (CRD42022327966).

Independent Clinical Impacts of Procedural Complexity on Ischemic and Bleeding Events in Patients with Acute Myocardial Infarction: Long-Term Clinical Study

This study aimed to investigate the relationship between a complex percutaneous coronary intervention (C-PCI) and long-term clinical outcomes in the AMI cohort. A total of 10,329 patients were categorized into the C-PCI and non-C-PCI groups. The primary ischemic endpoint was a composite of major adverse cardiac events (MACEs, cardiac death, myocardial infarction, stent thrombosis and revascularization). The primary bleeding endpoint was the risk of overt bleeding (BARC 2, 3 or 5). The median follow-up duration was 4.9 (2.97, 7.16) years. The risks of MACEs and bleeding were significantly higher in the C-PCI group (hazard ratio (HR): 1.72; 95% confidence interval (CI): 1.60 to 1.85; p < 0.001; and HR: 1.32; 95% CI: 1.17 to 1.50; p < 0.001, respectively). After propensity score matching, compared to the non-C-PCI group, the adjusted MACE rate in C-PCI remained significantly higher (p < 0.001), but no significant interaction (p = 0.273) was observed for bleeding. Significant differences in overt bleeding were observed only within the first three months (p = 0.024). The MACEs were consistently higher in the C-PCI group with or without severe comorbid conditions (p < 0.001 for both). Patients with AMI who undergo C-PCI experience worse long-term ischemic outcomes after successful PCI, regardless of the presence of severe comorbidities.

Effectiveness of Direct Laser Interference Patterning and Peptide Immobilization on Endothelial Cell Migration for Cardio-Vascular Applications: An In Vitro Study

Endothelial coverage of an exposed cardiovascular stent surface leads to the occurrence of restenosis and late-stent thrombosis several months after implantation. To overcome this difficulty, modification of stent surfaces with topographical or biochemical features may be performed to increase endothelial cells’ (ECs) adhesion and/or migration. This work combines both strategies on cobalt-chromium (CoCr) alloy and studies the potential synergistic effect of linear patterned surfaces that are obtained by direct laser interference patterning (DLIP), coupled with the use of Arg-Gly-Asp (RGD) and Tyr-Ile-Gly-Ser-Arg (YIGSR) peptides. An extensive characterization of the modified surfaces was performed by using AFM, XPS, surface charge, electrochemical analysis and fluorescent methods. The biological response was studied in terms of EC adhesion, migration and proliferation assays. CoCr surfaces were successfully patterned with a periodicity of 10 µm and two different depths, D (≈79 and 762 nm). RGD and YIGSR were immobilized on the surfaces by CPTES silanization. Early EC adhesion was increased on the peptide-functionalized surfaces, especially for YIGSR compared to RGD. High-depth patterns generated 80% of ECs’ alignment within the topographical lines and enhanced EC migration. It is noteworthy that the combined use of the two strategies synergistically accelerated the ECs’ migration and proliferation, proving the potential of this strategy to enhance stent endothelialization.

Long-term clinical outcomes of everolimus-eluting bioresorbable scaffolds versus everolimus-eluting stents: final five-year results of the AIDA randomised clinical trial

BACKGROUND

Absorb bioresorbable vascular scaffold (BVS)-related events have been reported between 1 and 3 years - the period of active scaffold bioresorption. Data on the performance of the Absorb BVS in daily clinical practice beyond this time point are scarce.

AIMS

This report aimed to provide the final five-year clinical follow-up of the Absorb BVS in comparison with the XIENCE everolimus-eluting stent (EES). In addition, we evaluated the effect of prolonged dual antiplatelet therapy (DAPT) administration on events in the scaffold group.

METHODS

AIDA was a multicentre, investigator-initiated, non-inferiority trial, in which 1,845 unselected patients with coronary artery disease were randomly assigned to either the Absorb BVS (n=924) or the XIENCE EES (n=921). Target vessel failure (TVF), a composite of cardiac death, target vessel myocardial infarction or target vessel revascularisation, was the primary endpoint. Scaffold thrombosis cases were matched with controls and tested for the effect of prolonged DAPT.

RESULTS

Up to five-year follow-up, there was no difference in TVF between the Absorb BVS (17.7%) and the XIENCE EES (16.1%) (hazard ratio [HR] 1.31, 95% confidence interval [CI]: 0.90-1.41; p=0.302). Definite or probable device thrombosis (DT) occurred in 43 patients (4.8%) in the scaffold group compared to 13 patients (1.5%) in the stent group (HR 3.32, 95% CI: 1.78-6.17; p<0.001). DT between 3 and 4 years occurred six times in the Absorb arm versus three times in the XIENCE arm. Between 4 and 5 years, the incidence was three versus two, respectively. Of those three DT in the scaffold group, two occurred in XIENCE EES-treated lesions. The odds ratio of scaffold thrombosis in patients on DAPT compared to off DAPT throughout five-year follow-up was 0.36 (95% CI: 0.15-0.86).

CONCLUSIONS

The excess risk of the Absorb BVS on late adverse events, in particular device thrombosis, in routine PCI continues up to 4 years and seems to plateau afterwards. Clinical Trial Registration ClinicalTrials.gov: NCT01858077.

The Mechanisms of Restenosis and Relevance to Next Generation Stent Design

Stents are lifesaving mechanical devices that re-establish essential blood flow to the coronary circulation after significant vessel occlusion due to coronary vessel disease or thrombolytic blockade. Improvements in stent surface engineering over the last 20 years have seen significant reductions in complications arising due to restenosis and thrombosis. However, under certain conditions such as diabetes mellitus (DM), the incidence of stent-mediated complications remains 2–4-fold higher than seen in non-diabetic patients. The stents with the largest market share are designed to target the mechanisms behind neointimal hyperplasia (NIH) through anti-proliferative drugs that prevent the formation of a neointima by halting the cell cycle of vascular smooth muscle cells (VSMCs). Thrombosis is treated through dual anti-platelet therapy (DAPT), which is the continual use of aspirin and a P2Y₁₂ inhibitor for 6–12 months. While the most common stents currently in use are reasonably effective at treating these complications, there is still significant room for improvement. Recently, inflammation and redox stress have been identified as major contributing factors that increase the risk of stent-related complications following percutaneous coronary intervention (PCI). The aim of this review is to examine the mechanisms behind inflammation and redox stress through the lens of PCI and its complications and to establish whether tailored targeting of these key mechanistic pathways offers improved outcomes for patients, particularly those where stent placement remains vulnerable to complications. In summary, our review highlights the most recent and promising research being undertaken in understanding the mechanisms of redox biology and inflammation in the context of stent design. We emphasize the benefits of a targeted mechanistic approach to decrease all-cause mortality, even in patients with diabetes.

Safety and Efficacy of Bioresorbable Vascular Scaffolds in Coronary Bifurcation Lesions: A Systematic Review and Meta-Analysis

INTRODUCTION

Coronary bifurcation lesions (CBL) are one fifth of all coronary lesions and they do not have an optimal strategy for stenting yet. Bioresorbable scaffolds (BRS) are novel inventions proposed to be the optimal solution. The aim of this systematic review was to assess the role of BRS in treating CBL by comparing it to dedicated bifurcation stents (DBS).

METHODS

A systematic review was conducted following the PRISMA guidelines, searching databases such as ScienceDirect, EMBASE, MEDLINE, NIH, TRIP, PUBMED, and ClinicalTrials. gov. The risk of bias was assessed by MINORS and modified Cowley's criteria. Q statistic was used for heterogeneity testing and a meta-analysis was conducted using the "meta" package in the R software application.

RESULTS

Fourteen studies were included with an average follow-up period of twelve months. Almost 80% of the participants were male (p-value= 0.148) and around two-thirds were smokers. Meta-analysis was performed for myocardial infarction (MI), target lesion revascularisation (TLR), major adverse cardiac events (MACE), and stent thrombosis (ST). These showed statistically nonsignificant differences, with a slight trend favouring BRS except with stent thrombosis.

CONCLUSION

There is a lack of randomised trials on the topic, which may be an area for further research. But the results showed favourable yet statistically insignificant outcomes for BRS except for ST, an issue that can be addressed with technological advancement.

Overcoming challenges in refining the current generation of coronary stents

INTRODUCTION

Late stent thrombosis caused by delayed vascular healing and prolonged local inflammation were major drawbacks of 1^st generation drug-eluting stents (DES). Strut design, biocompatibility of polymer, and drug-release profiles were improved in 2^nd and 3rdgeneration DES. Accordingly, the indications for percutaneous coronary intervention with DES have been expanded to more complex patients and lesions. Despite these improvements, significant barriers such as greater flexibility in the duration of dual-antiplatelet therapy (DAPT) as well as reducing long-term stent-related events remain. To achieve ideal short- and long-term results, these existing limitations need to be overcome.

AREAS COVERED

We will discuss the current limitations of coronary DES and how they might be overcome from pathological and clinical viewpoints.

EXPERT OPINION

Optimizing DAPT duration after stent implantation and prevention of in-stent neoatherosclerosis are two major issues in current DES. Overcoming these drawbacks is a prerequisite toward achieving better short- and long-term clinical outcomes. New technologies including platform design, polymer types, and anti-proliferative agent itself might lead to further improvements. Although the initial experience with bioresorbable scaffold/stents (BRS) was disappointing, positive results of clinical studies regarding novel BRS are raising expectations. Overall, further device innovation is desired for overcoming the limitations of current DES.

Challenges to the development of the next generation of self-reporting cardiovascular implantable medical devices

Cardiovascular disease (CVD) is a group of heart and vasculature conditions which are the leading form of mortality worldwide. Blood vessels can become narrowed, restricting blood flow, and drive the majority of hearts attacks and strokes. Surgical interventions are frequently required; including percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG). Despite successful opening of vessels and restoration of blood flow, often in-stent restenosis (ISR) and graft failure can still occur, resulting in subsequent patient morbidity and mortality. A new generation of cardiovascular implants that have sensors and real-time monitoring capabilities are being developed to combat ISR and graft failure. Self-reporting stent/graft technology could enable precision medicine-based healthcare by detecting the earliest features of disease, even before symptoms occur. Bringing an implantable medical device with wireless electronic sensing capabilities to market is complex and often obstructive undertaking. This critical review analyses the obstacles that need to be overcome for self-reporting stents/grafts to be developed and provide a precision-medicine based healthcare for cardiovascular patients. Here we assess the latest research and technological advancement in the field, the current devices and the market potential for their end-user implementation.

Physiological assessment after percutaneous coronary intervention: the hard truth

Physiologically guided revascularization, using Fractional Flow Reserve (FFR) or instantaneous wave free ratio (iFR) has been demonstrated to be associated with better long-term outcomes compared to an angiographically-guided strategy, mainly avoiding inappropriate coronary stenting and its associated adverse events. On the contrary, the role of invasive physiological assessment after percutaneous coronary intervention (PCI) is much less well established. However, a large body of evidence suggests that a relevant proportion of patients undergoing PCI with a satisfying angiographic result show instead a suboptimal functional product with a potentially negative prognostic impact. For this reason, many efforts have been focused to identify interventional strategies to physiologically optimize PCI. Measuring the functional result after as PCI, especially when performed after a physiological assessment, implies that the operator is ready to accept the hard truth of an unsatisfactory physiological result despite angiographically optimal and, consequently, to optimize the product with some additional effort. The aim of this review is to bridge this gap in knowledge by better defining the paradigm shift of invasive physiological assessment from a simple tool for deciding whether an epicardial stenosis has to be treated to a thoroughly physiological approach to PCI with the suggestion of a practical flow chart.

Clinical outcomes three-year after revascularization with biodegradable polymer stents: ultrathin-strut sirolimus-eluting stent versus biolimus-eluting stent: from the Scandinavian organization for randomized trials with clinical outcome VII trial

BACKGROUND

Drug-eluting stents with biodegradable polymers have been designed to improve safety and efficacy. However, drug-eluting stents with biodegradable polymers may not be a class effect, as stent strut thickness, polymer coating, and drug resorption differ between these groups of stents. Twelve months results of Scandinavian Organization for Randomized Trials With Clinical Outcome VII showed that ultrathin-strut sirolimus-eluting Orsiro stent was noninferior to the biolimus-eluting Nobori stent. The sirolimus-eluting Orsiro stent was associated with a reduced risk of definite stent thrombosis.

METHODS

The Scandinavian Organization for Randomized Trials With Clinical Outcome VII trial is a prospective multicenter randomized clinical trial comparing sirolimus-eluting Orsiro stent and biolimus-eluting Nobori stent in all-comers patients. The endpoint target lesion failure was a composite of cardiac death, myocardial infarction (not related to other than index lesion) and target lesion revascularization.

RESULTS

A total of 1261 patients were randomized to treatment with sirolimus-eluting Orsiro stent and 1264 patients to biolimus-eluting Nobori stent and followed for 3 years. At 3-year the target lesion failure was comparable for sirolimus-eluting Orsiro stent (9.0%) and the biolimus-eluting Nobori stent (9.1%), (rate ratio, 0.99; 95% confidence interval, 0.77-1.29). Cardiac death (sirolimus-eluting Orsiro stent 3.0% vs. biolimus-eluting Nobori stent 2.6% [rate ratio, 1.16; 95% confidence interval, 0.73-1.86]), target lesion revascularization (sirolimus-eluting Orsiro stent 5.2% vs. biolimus-eluting Nobori stent 5.9% [rate ratio, 0.90; 95% confidence interval, 0.64-1.25]), myocardial infarction (sirolimus-eluting Orsiro stent 4.7% vs. biolimus-eluting Nobori stent 4.5% [rate ratio, 1.04; 95% confidence interval, 0.72-1.50]), and definite stent thrombosis (sirolimus-eluting Orsiro stent 1.0% vs. biolimus-eluting Nobori stent 1.7% [rate ratio, 0.59; 95% confidence interval, 0.30-1.18]) did not differ significantly between the two groups.

CONCLUSION

At 3-year follow-up, target lesion failure did not differ among ultrathin-strut sirolimus-eluting Orsiro stent and biolimus-eluting Nobori stent with biodegradable polymers.

Efficacy and Safety of Dual Antiplatelet Therapy in Patients Undergoing Coronary Stent Implantation: A Systematic Review and Network Meta-Analysis

Introduction

This network meta-analysis aimed to evaluate the efficacy and safety of different dual antiplatelet therapies (DAPTs) after percutaneous coronary intervention (PCI) with drug-eluting stents (DESs).

Methods

Randomized controlled trials (RCTs) comparing longer-term (>12 months) DAPT (L-DAPT), 12-month DAPT (DAPT 12Mo), 6-month DAPT (DAPT 6Mo), 3-month DAPT followed by aspirin monotherapy (DAPT 3Mo + ASA), 3-month DAPT followed by a P2Y12 receptor inhibitor monotherapy (DAPT 3Mo + P2Y12), or 1-month DAPT with a P2Y12 receptor inhibitor monotherapy (DAPT 1Mo + P2Y12) were searched. Primary endpoints were all-cause mortality, cardiac death, myocardial infarction (MI), major bleeding, any bleeding, definite or probable stent thrombosis (ST), and net adverse clinical events (NACE). This Bayesian network meta-analysis was performed with the random-effects model.

Results

Twenty-four RCTs (n = 81339) were included. In comparison with L-DAPT, DAPT 6Mo (OR: 0.50, 95% CI: 0.29–0.83), DAPT 3Mo + P2Y12 (OR: 0.38, 95% CI: 0.18–0.82), DAPT 3Mo + ASA (OR: 0.44, 95% CI: 0.17–0.98), and DAPT 1Mo + P2Y12 (OR: 0.45, 95% CI: 0.14–0.93) were associated with a lower risk of major bleeding. DAPT 3Mo + P2Y12 (OR: 0.58, 95% CI: 0.38–0.88) reduced the risk of any bleeding when compared with DAPT 12Mo. L-DAPT decreased the risk of MI and definite or probable stent ST when compared with DAPT 6Mo. DAPT 3Mo + P2Y12 decreased the risk of NACE in comparison with DAPT 6Mo and DAPT 12Mo. No significant difference in all-cause mortality and cardiac death was observed. In patients with acute coronary syndrome, DAPT 6Mo was comparable to DAPT 12Mo.

Conclusion

Short-term (1–3 months) DAPT is noninferior to DAPT 6Mo after DESs implantation, while L-DAPT reduces MI and definite or probable ST rates. DAPT 3Mo + P2Y12 might be a reasonable trade-off in patients with high risk of bleeding accompanied by ischemia.

Effects of electret coating technology on coronary stent thrombogenicity

Stent thrombosis (ST) is a catastrophic event and efforts to reduce its incidence by altering blood-stent interactions are longstanding. A new electret coating technology that produces long-lasting negative charge on stent surface could make them intrinsically resistant to thrombosis. We assessed the thrombogenicity of stents using an annular perfusion model with confocal microscopy, and determined the efficacy of electret coating technology to confer thrombo-resistant properties to standard stents. Using an annular perfusion chamber, Bare Metal Stent (BMS), standard uncoated DES (DES), and Electret-coated DES (e-DES) were exposed to human blood under arterial flow conditions. Deposits of fibrinogen and platelets on the stent surface were analyzed using immunofluorescence staining and confocal microscopy. Surface coverage by fibrinogen and platelets and the deposit/aggregate size were quantified using computerized morphometric analysis. The experimental methodology produced consistent, quantifiable results. Area of stent surface covered by fibrinogen and platelets and the average size of the deposits/aggregates were lowest for e-DES and highest on BMS, with DES in the middle. The size of fibrinogen-deposits showed no differences between the stents. The testing methodology used in our study successfully demonstrated that electret coating confers significant antithrombotic property to DES stents. These findings warrant confirmation in a larger study.

Final 5-Year Results in Randomized Japanese Patients Implanted With a Thin-Strut, Bioabsorbable, Polymer-Coated, Everolimus-Eluting SYNERGY Stent (From the EVOLVE II Study)

Background: SYNERGY is a thin-strut, platinum-chromium metal alloy stent with an ultrathin abluminal everolimus-eluting bioabsorbable polymer. EVOLVE II was a global randomized controlled trial that enrolled 1,684 patients treated with either a SYNERGY or durable polymer PROMUS Element Plus (PE+) everolimus-eluting stent, including 155 patients from Japanese sites. This substudy analyzed 5-year clinical outcomes in the Japanese and non-Japanese cohorts.

Methods and Results: Patients aged ≥18 years with ≤3 native coronary artery lesions (reference vessel diameter ≥2.25–≤4.00 mm; length ≤34 mm) in ≤2 major vessels were randomized 1 : 1 to receive either SYNERGY (n=74 patients in Japan) or PE+ (n=81 patients in Japan). Five-year target lesion failure (TLF) was observed in 8.3% SYNERGY- and 11.2% PE+-treated patients (P=0.54). There were no cardiac deaths, and rates of target lesion revascularization and myocardial infarction were comparable between treatment arms. One patient in the SYNERGY arm experienced a very late definite stent thrombosis (ST); no ST occurred in the PE+ arm (P=0.30). Despite differences in baseline clinical and lesion characteristics, the 5-year TLF rates were not significantly different in SYNERGY-treated patients either in (8.3%) or outside (14.8%) Japan (P=0.14).

Conclusions: In Japanese patients with coronary artery disease, SYNERGY showed comparable efficacy to PE+, with low rates of adverse events over 5 years. Similarly, 5-year clinical outcomes were favorable in Japanese vs. non-Japanese patients implanted with SYNERGY.

Bioresorbable Scaffolds: Contemporary Status and Future Directions

Percutaneous coronary intervention, which is safe, effective, and timely, has become an important treatment for coronary artery diseases and has been widely used in clinical practice. However, there are still some problems that urgently need to be solved. Permanent vessel caging through metallic implants not only prevents the process of positive vessel remodeling and the restoration of vascular physiology but also makes the future revascularization of target vessels more difficult. Bioresorbable scaffolds (BRSs) have been developed as a potential solution to avoid the above adverse reactions caused by permanent metallic devices. BRSs provide temporary support to the vessel wall in the short term and then gradually degrade over time to restore the natural state of coronary arteries. Nonetheless, long-term follow-up of large-scale trials has drawn considerable attention to the safety of BRSs, and the significantly increased risk of late scaffold thrombosis (ScT) limits its clinical application. In this review, we summarize the current status and clinical experiences of BRSs to understand the application prospects and limitations of these devices. In addition, we focus on ScT after implantation, as it is currently the primary drawback of BRS. We also analyze the causes of ScT and discuss improvements required to overcome this serious drawback and to move the field forward.

Randomized comparison between bare-metal stent plus colchicine versus drug-eluting stent alone in prevention of clinical adverse events after percutaneous coronary intervention

The use of colchicine is associated with a significant reduction of cardiac adverse events in patients with coronary artery disease. Past small randomized trials with oral immunosuppressive or anti-inflammatory therapies have demonstrated a reduction of adverse clinical events after bare metal stent implantation. The potential role of adjunctive colchicine after bare-metal stent implantation, compared with drug-eluting stent alone, is unknown. The primary end point of the study will be to compare cost-effectiveness at 1 year of follow-up of coronary intervention with bare-metal stent implantation plus 1 mg of colchicine during 3 months versus percutaneous coronary intervention with drug-eluting stent implantation alone. ClinicalTrials.gov identifier: NCT04382443.

Final report of the 5-year clinical outcomes of the XINSORB bioresorbable sirolimus-eluting scaffold in the treatment of single de novo coronary lesions in a first-in-human study

Background

We aimed to report the 5-year outcomes of XINSORB bioresorbable sirolimus-eluting scaffolds in the treatment of single de novo coronary lesions in a first-in-human (FIM) study. This is the final report of the long-term clinical outcomes of the study. Recent studies have shown that bioresorbable scaffolds (BRSs) increase the risks of late target lesion failure (TLF) and thrombosis.

Methods

In this prospective, single-arm study, eligible patients with single de novo coronary lesions were enrolled and treated with XINSORB scaffolds. The scaffolds measured 3.0 mm in diameter and 12, 15, and 18 mm in length. The clinical endpoints included TLF [cardiac death, target vessel-related myocardial infarction (TV-MI), or ischaemia-driven target lesion revascularization (ID-TLR)], its components, major adverse cardiac events (MACE), and scaffold thrombosis.

Results

From September 2013 to January 2014, 30 patients were enrolled and treated with XINSORB scaffolds. The procedure had a 100% success rate. None of the patients died during the 5 years of follow-up. The primary endpoint of TLF occurred in 4 patients (13.3%). Six patients were recanalized by intervention, including 4 by ID-TLR. The rate of MACE was 16.7% (5/30). One very late case of scaffold thrombosis was recorded, which led to TV-MI. No more cases of thrombosis were recorded beyond 2 years of follow-up. The rates of clinical endpoints remained steady with no changes after 3 years of follow-up.

Conclusions

Considering that this FIM study was launched at an early stage of the BRS era and without optimal implantation techniques, the clinical outcomes of TLF during the 5-year follow-up were acceptable. The rate of thrombosis was relatively low.

Three-year outcomes of bioresorbable vascular scaffolds versus second-generation drug-eluting stents: Meta-analysis of randomized trials

BACKGROUND

Bioresorbable vascular scaffolds (BVS) completely resorb within 3 years after placement into the coronary artery. The safety and effectiveness of bioabsorbable scaffolds are of critical importance during this 3-year period.

OBJECTIVE

We performed a meta-analysis to compare the safety and efficacy of BVS and second-generation drug-eluting stents (DES) at 3 years after implantation.

METHODS

Published randomized trials comparing BVS to second-generation DES for the treatment of coronary artery disease were identified within PubMed, EMBASE, Cochrane Library, Web of Science, and relevant Web sites with publication dates through June 2019. The primary efficacy endpoint was target lesion failure. The primary safety endpoint was definite/probable stent/scaffold thrombosis. Secondary outcomes were cardiac death, target vessel myocardial infarction, ischemia-driven target lesion revascularization, and a patient-oriented composite end point.

RESULTS

Six randomized controlled trials, with a total of 5,412 patients (BVS n = 3,177; DES n = 2,235), were included. At 3 years, BVS was associated with higher rates of target lesion failure (OR = 1.33, 95%CI: 1.10-1.60, P = 0.003) and definite/probable stent/scaffold thrombosis (OR = 3.75, 95% CI: 2.22-6.35, P < .00001)compared with DES. The incidence of target vessel myocardial infarction (OR = 1.68, 95% CI: 1.30-2.17, P < .0001), ischemia-driven target lesion revascularization (OR = 1.46, 95% CI: 1.14-1.86, P = .003), and the patient-oriented composite end point(OR = 1.20, 95% CI: 1.04-1.39, P = .01) were higher for those treated with BVS compared with DES. However, there was no significant difference in risk of cardiac death (OR = 0.94, 95%CI: 0.61-1.45, P = .79) between treatment groups.

CONCLUSIONS

At the 3-year follow-up, BVS was inferior to second-generation DES in both safety and efficacy.

Hybrid intervention approach to coronary artery and valvular heart disease

Coronary angiography is used to assess the burden of coronary artery disease prior to surgical valve repair/replacement and often leads to concomitant bypass and valve surgery. We sought to evaluate outcomes of an alternative, hybrid approach involving percutaneous coronary intervention (PCI) and valve surgery, assessing the rate of stent thrombosis as a primary outcome. We reviewed charts of consecutive patients who underwent planned PCI prior to surgical valve repair/replacement by a single surgeon from January 2008 to December 2016. We calculated rates of surgical complication, duration of dual antiplatelet therapy (DAPT) prior to surgery, and rates of stent thrombosis and in-stent restenosis. Twenty-four patients were included in this study. Surgery was performed a median of 52.5 days following PCI. DAPT was withheld an average of 8 days before and resumed an average of 4 days after surgery. Ninety-two percent of surgeries were minimally invasive. There were no bleeding complications, stent thromboses, or restenosis events. All patients survived the 1-year follow-up. For patients with mixed coronary and valvular heart disease, a heart team approach involving preoperative PCI followed by staged minimally invasive valvular surgery appears to be safe and warrants further exploration.

The optimal duration of dual antiplatelet therapy in East Asian patients undergoing percutaneous coronary intervention with drug-eluting stents: a meta-analysis of randomized trials

OBJECTIVE

The optimal duration of dual antiplatelet therapy (DAPT) is still controversial among East Asians. This meta-analysis was designed to evaluate the efficacy and safety of short-term (≤6 months) vs. long-term (≥12 months) DAPT in East Asians undergoing percutaneous coronary intervention (PCI) with drug-eluting stent (DES).

METHODS

PubMed, Embase, Web of Science and the Cochrane Library were searched for articles published up to 30 March 2020. Then meta-analysis was performed using RevMan 5.3 software.

RESULTS

Nine studies with a total of 20 177 East Asian patients were included in this meta-analysis. In East Asian patients, short-term DAPT was associated with a lower incidence of major bleeding [odds ratio (OR) = 0.70, 95% confidence interval (CI) (0.49, 0.99), P = 0.04]. In the newer-generation DES subgroup, short-term DAPT was no less effective than long-term DAPT and resulted in a lower incidence of major bleeding [OR = 0.69, 95% CI (0.49, 0.98), P = 0.04]. In the subgroup of patients with acute coronary syndrome, there was no significant difference in the incidence of cardiac death, net adverse clinical and cerebral events (NACCE) and major bleeding between short-term and long-term DAPT. It was worth noting that in the subgroup of patients with diabetes mellitus, short-term DAPT was associated with a higher incidence of myocardial infarction [OR = 2.64, 95% CI (1.19, 5.88), P = 0.02] and NACCE [OR = 1.92, 95% CI (1.07, 3.43), P = 0.03].

CONCLUSION

The short-term DAPT (≤6 months) might be a better choice for East Asian patients undergoing PCI with DES, especially the newer-generation DES. However, for high-risk patients such as diabetes, the analysis supported the longer DAPT.

Combination of Oral Anticoagulants and Single Antiplatelets versus Triple Therapy in Nonvalvular Atrial Fibrillation and Acute Coronary Syndrome: Stroke Prevention among Asians

Atrial fibrillation (AF), the most prevalent arrhythmic disease, tends to foster thrombus formation due to hemodynamic disturbances, leading to severe disabling and even fatal thromboembolic diseases. Meanwhile, patients with AF may also present with acute coronary syndrome (ACS) and coronary artery disease (CAD) requiring stenting, which creates a clinical dilemma considering that majority of such patients will likely receive oral anticoagulants (OACs) for stroke prevention and require additional double antiplatelet treatment (DAPT) to reduce recurrent cardiac events and in-stent thrombosis. In such cases, the gentle balance between bleeding risk and atherothromboembolic events needs to be carefully considered. Studies have shown that congestive heart failure, hypertension, age ≥ 75 years (doubled), diabetes mellitus, and previous stroke or transient ischemic attack (TIA; doubled)-vascular disease, age 65 to 74 years, sex category (female; CHA ₂ DS ₂ -VASc) scores outperform other scoring systems in Asian populations and that the hypertension, abnormal renal/liver function (1 point each), stroke, bleeding history or predisposition, labile international normalized ratio (INR), elderly (>65 years), drugs/alcohol concomitantly (1 point each; HAS-BLED) score, a simple clinical score that predicts bleeding risk in patients with AF, particularly among Asians, performs better than other bleeding scores. A high HAS-BLED score should not be used to rule out OAC treatment but should instead prompt clinicians to address correctable risk factors. Therefore, the current review attempted to analyze available data from patients with nonvalvular AF who underwent stenting for ACS or CAD and elaborate on the direct-acting oral anticoagulant (DOAC) and antiplatelet management among such patients. For majority of the patients, "triple therapy" comprising OAC, aspirin, and clopidogrel should be considered for 1 to 6 months following ACS. However, the optimal duration for "triple therapy" would depend on the patient's ischemic and bleeding risks, with DOACs being obviously safer than vitamin-K antagonists.

Long versus short dual antiplatelet therapy in acute coronary syndrome patients treated with prasugrel or ticagrelor and coronary revascularization: Insights from the RENAMI registry

Introduction

The benefits of short versus long-term dual antiplatelet therapy (DAPT) based on the third generation P2Y12 antagonists prasugrel or ticagrelor, in patients with acute coronary syndromes treated with percutaneous coronary intervention remain to be clearly defined due to current evidences limited to patients treated with clopidogrel.

Methods

All acute coronary syndrome patients from the REgistry of New Antiplatelets in patients with Myocardial Infarction (RENAMI) undergoing percutaneous coronary intervention and treated with aspirin, prasugrel or ticagrelor were stratified according to DAPT duration, that is, shorter than 12 months (D1 group), 12 months (D2 group) and longer than 12 months (D3 group). The three groups were compared before and after propensity score matching. Net adverse clinical events (NACEs), defined as a combination of major adverse cardiac events (MACEs) and major bleedings (including therefore all cause death, myocardial infarction and Bleeding Academic Research Consortium (BARC) 3–5 bleeding), were the primary end points, MACEs (a composite of all cause death and myocardial infarction) the secondary one. Single components of NACEs were co-secondary end points, along with BARC 2–5 bleeding, cardiovascular death and stent thrombosis.

Results

A total of 4424 patients from the RENAMI registry with available data on DAPT duration were included in the model. After propensity score matching, 628 patients from each group were selected. After 20 months of follow up, DAPT for 12 months and DAPT for longer than 12 months significantly reduced the risk of NACE (D1 11.6% vs. D2 6.7% vs. D3 7.2%, p = 0.003) and MACE (10% vs. 6.2% vs. 2.4%, p < 0.001) compared with DAPT for less than 12 months. These differences were driven by a reduced risk of all cause death (7.8% vs. 1.3% vs. 1.6%, p < 0.001), cardiovascular death (5.1% vs. 1.0% vs. 1.2%, p < 0.0001) and recurrent myocardial infarction (8.3% vs. 5.2% vs. 3.5%, p = 0.002). NACEs were lower with longer DAPT despite a higher risk of BARC 2–5 bleedings (4.6% vs. 5.7% vs. 6.2%, p = 0.04) and a trend towards a higher risk of BARC 3–5 bleedings (2.4% vs. 3.3% vs. 3.9%, p = 0.06). These results were not consistent for female patients and those older than 75 years old, due to an increased risk of bleedings which exceeded the reduction in myocardial infarction.

Conclusion

In unselected real world acute coronary syndrome patients treated with percutaneous coronary intervention, DAPT with prasugrel or ticagrelor prolonged beyond 12 months markedly reduces fatal and non-fatal ischaemic events, offsetting the increased risk deriving from the higher bleeding risk. On the contrary, patients >75 years old and female ones showed a less favourable risk–benefit ratio for longer DAPT due to excess of bleedings.

Long-Term Safety and Efficacy of Durable Polymer Cobalt-Chromium Everolimus-Eluting Stents in Patients at High Bleeding Risk

Background:

Long-term outcomes in patients at high bleeding risk (HBR) undergoing percutaneous coronary intervention with a drug-eluting stent are unclear. Therefore, we aimed to evaluate long-term adverse events in HBR patients undergoing percutaneous coronary intervention with cobalt-chromium everolimus-eluting stent implantation.

Methods:

We analyzed stratified data from 4 all-comers postapproval registries. Patients with at least 1 of the following criteria were categorized as HBR: age ≥75 years, history of major bleeding (MB), history of stroke, chronic oral anticoagulant use, chronic kidney disease, anemia, or thrombocytopenia. Additionally, in a separate analysis, patients were categorized according to the recently published Academic Research Consortium HBR criteria. The Kaplan-Meier method was used for time-to-event analyses. Coronary thrombotic events (CTE) included myocardial infarction or definite/probable stent thrombosis. MB was defined according to the TIMI (Thrombolysis in Myocardial Infarction) or GUSTO (Global Use of Strategies to Open Occluded Coronary Arteries) scales. Impact of CTE and MB on subsequent risk of mortality was assessed using multivariable Cox regression with MB and CTE included as time-updated covariates.

Results:

Of the total 10 502 patients included, 3507 (33%) were identified as HBR. Compared with non-HBR patients, those at HBR had more comorbidities, higher lesion complexity, and a higher risk of 4-year mortality (Hazard Ratio [HR] 4.38 [95% CI, 3.76–5.11]). Results were qualitatively similar when using Academic Research Consortium criteria to define HBR. Risk of mortality was increased after CTE (HR 5.02 [95% CI, 3.93–6.41]), as well as after MB (HR 4.92 [95% CI, 3.82–6.35]). Of note, this effect was consistent across the spectrum of bleeding risk ( P -interaction test 0.97 and 0.06, respectively).

Conclusions:

Compared with the non-HBR population, HBR patients experienced worse 4-year outcomes after percutaneous coronary intervention with cobalt-chromium everolimus-eluting stent. Both CTE and MB had a significant impact on subsequent risk of mortality irrespective of bleeding risk.

Three-year follow up of biodegradable polymer cobalt-chromium sirolimus-eluting stent (EXCROSSAL) in treating de novo coronary artery disease: Pooled analysis of CREDIT II and CREDIT III trials

OBJECTIVES

To analyze the 3-year outcomes of the biodegradable polymer cobalt-chromium sirolimus-eluting stent (EXCROSSAL) in CREDIT II AND III TRIALS.

BACKGROUND

Though approved by CFDA, the long-term safety and efficacy of EXCROSSAL is still unknown.

METHODS

CREDIT II was a randomized trial comparing the EXCROSSAL versus EXCEL stents in patients with up to two de novo coronary lesions, and CREDIT III was a prospective, single-arm study evaluating the efficacy and safety of EXCROSSAL in broad types of de novo coronary artery lesions. We pooled the 3-year follow-up data of the EXCROSSAL arm of the CREDIT II and CREDIT III Trials. The primary outcome was 3-year target lesion failure (TLF), a composite of cardiac death, target vessel myocardial infarction (TV-MI), and clinically indicated target lesion revascularization (CI-TLR). The patient-oriented composite endpoint (PoCE) (all-cause death, all MI, or any revascularization) and stent thrombosis (ST) were also analyzed.

RESULTS

A total of 833 patients were included in this study. The incidence of TLF and PoCE in the 3-year follow-up were 7.6% and 12.5%, respectively. ST occurred in 0.6% of patients. In the subgroup analyses, TLF was significantly higher in small target vessels, multi-lesion PCI, and multi-vessel disease.

CONCLUSIONS

The 3-year follow-up analysis confirmed low rates of TLF and ST in EXCROSSAL, which is similar to the most widely used new generation durable polymer drug-eluting stent.

Augmented re-endothelialization and anti-inflammation of coronary drug-eluting stent by abluminal coating with magnesium hydroxide

Drug-eluting stents (DESs) have been widely used as a treatment approach for coronary artery diseases. Generally, conventional DESs were fully covered with drugs and biodegradable polymers on both abluminal and luminal layers (i.e., conformal coating). However, uncontrolled drug release from the luminal drug-coating layer of the stent is known to inhibit re-endothelialization. Furthermore, the acidification of the surrounding tissue by the decomposed coating polymer causes inflammation, resulting in restenosis and late thrombosis. To overcome these limitations, here we demonstrated a functional DES coated with poly(lactic-co-glycolic acid) (PLGA), sirolimus (SRL), and magnesium hydroxide (Mg(OH)2, MH) precisely only on the abluminal layer. The acidic neutralization effect of MH was elucidated by measuring the pH change of the fabricated film in PBS solution. In an in vitro cell study, the stent coated with MH exhibited higher compatibility with human coronary artery endothelial cells (ECs) and a lower inflammation score as compared to the control stent. Finally, in an in vivo large porcine model, the abluminal coated DES with SRL and MH showed excellent re-endothelialization and anti-inflammatory and anti-thrombotic effects. In conclusion, it is believed that this approach has great potential for the development of functional DES for the treatment of cardiovascular diseases.

Three-year clinical outcome of biodegradable hybrid polymer Orsiro sirolimus-eluting stent and the durable biocompatible polymer Resolute Integrity zotarolimus-eluting stent: A randomized controlled trial

AIMS

We compared long-term clinical outcomes between patients treated with Orsiro sirolimus-eluting stent (O-SES) and those treated with durable biocompatible polymer Resolute Integrity zotarolimus-eluting stent (R-ZES).

METHODS AND RESULTS

The ORIENT trial was a randomized controlled noninferiority trial to compare angiographic outcomes between O-SES and R-ZES. We performed a post hoc analysis of 3-year clinical outcomes and included 372 patients who were prospectively enrolled and randomly assigned to O-SES (n = 250) and R-ZES (n = 122) groups in a 2:1 ratio. The primary endpoint was target lesion failure defined as a composite of cardiac death, nonfatal myocardial infarction, and target lesion revascularization. At 3 years, target lesion failure occurred in 4.7% and 7.8% of O-SES and R-ZES groups, respectively (hazard ratio, 0.58; 95% confidence intervals, 0.24-1.41; p = .232 by log-rank test). Secondary endpoints including cardiac death, myocardial infarction, and target lesion revascularization showed no significant differences between the groups. Stent thrombosis occurred in two patients in R-ZES group (0.0% vs. 1.6%, p = .040).

CONCLUSION

This study confirms long-term safety and efficacy of the two stents. We found a trend for lower target lesion failure with O-SES compared to R-ZES, although statistically insignificant.

A novel self-expanding primarily bioabsorbable braided flow-diverting stent for aneurysms: initial safety results

INTRODUCTION

The advent of metal flow-diverting stents has provided neurointerventionalists with an option for treating aneurysms without requiring manipulations within the aneurysm sac. The large amount of metal in these stents, however, can lead to early and late thrombotic complications, and thus requires long-term antiplatelet agents. Bioabsorbable stents have been postulated to mitigate the risk of these complications. Here we present early data on the first self-expandable primarily bioabsorbable stent for aneurysms.

METHODS

Braided stents were developed using poly-L-lactic acid fibers with material surface area similar to metal flow diverters. Crush resistance force, hemolysis, and thrombogenicity were determined and compared with existing commercial devices. Stents were deployed in infra-renal rabbit aortas to determine angiographic side branch patency and to study neointima formation for a 1-month follow-up period.

RESULTS

Crush resistance force was determined to be on the order of existing commercial devices. Hemolytic behavior was similar to existing metal devices, and thrombogenicity was lower than metal flow-diverting stents. A smooth neointimal layer was found over the absorbable stent surface and all covered side branches were patent at follow-up.

CONCLUSION

The design of self-expanding primarily bioabsorbable flow-diverting stents is possible, and preliminary safety data is consistent with a favorable profile in terms of mechanical behavior, hemocompatibility, side branch patency, and histological effects. Additional in vitro and long-term in vivo studies are in progress and will help determine aneurysm occlusion rates and absorption characteristics of the stent.

Efficacy and Safety of Ultrathin, Bioresorbable-Polymer Sirolimus-Eluting Stents Versus Thin, Durable-Polymer Everolimus-Eluting Stents for Coronary Revascularization of Patients With Diabetes Mellitus

Patients with diabetes mellitus are prone to increased adverse outcomes after percutaneous coronary intervention, even with contemporary drug-eluting stents. Randomized controlled trials have demonstrated comparable clinical outcomes between an ultrathin bioresorbable-polymer sirolimus-eluting stent (BP-SES) and a thin-strut durable-polymer everolimus-eluting stent (DP-EES) that has specific labeling for patients with diabetes. We aimed to evaluate the safety and efficacy of the BP-SES in patients with diabetes mellitus. To determine the performance of the BP-SES in diabetic patients, patient-level data from the BIOFLOW II, IV, and V randomized controlled trials were pooled. The primary end point was target lesion failure (TLF), defined as the composite of cardiovascular death, target-vessel myocardial infarction, ischemia-driven target lesion revascularization, and definite or probable stent thrombosis, at 1 year. Among 1,553 BP-SES and 791 DP-EES patients, 757 diabetic patients were identified. Of the diabetic patients included in this analysis (494 BP-SES vs 263 DP-EES), the proportion of insulin- and noninsulin-treated patients was similar between groups. The 1-year TLF rate in the diabetic population was 6.3% in the BP-SES group and 8.7% in the DP-EES group (hazard ratio 0.82, 95% confidence interval 0.047 to 1.43, p = 0.493). There were no significant differences, based on stent type or diabetes treatment regimen, in TLF hazards. In a patient-level pooled analysis of the diabetic population from randomized trials, 1-year clinical safety and efficacy outcomes were similar in patients treated with ultrathin BP-SES and thin-strut DP-EES.

Hybrid electrospun rapamycin-loaded small-diameter decellularized vascular grafts effectively inhibit intimal hyperplasia

For the surgical treatment of coronary artery disease, renal artery stenosis and other peripheral vascular diseases, there is significant demand for small diameter (inner diameter <6 mm) vascular grafts. However, autologous grafts are not always available when the substitute vascular grafts are severely diseased. In our previous work, hybrid small-diameter vascular grafts were successfully fabricated by combining electrospun polycaprolactone (PCL) and decellularized rat aorta (DRA). However, histological assessments of these grafts revealed the development of intimal hyperplasia, indicating potential negative impacts on the long-term patency of these grafts. To address this challenge, PCL nanofibers blended with rapamycin (RM) were electrospun outside the decellularized vascular graft to fabricate a RM-loaded hybrid tissue-engineered vascular graft (RM-HTEV), endowing the graft with a drug delivery function to prevent intimal hyperplasia. RM-HTEV possessed superior mechanical properties compared to DRA and exhibited a sustained drug release profile. To evaluate the applicability of RM-HTEV in vivo, abdominal aorta transplantation was performed on rats. Doppler sonography showed that the grafts were functional for up to 8 weeks in vivo. Moreover, histological analysis of explanted grafts 12 weeks postimplantation demonstrated that RM-HTEV significantly decreased neo-intimal hyperplasia compared with HTEV, without impairing reendothelialization and M2 macrophage polarization. Overall, RM-HTEV represents a promising strategy for developing small-diameter vascular grafts with great clinical translational potential. STATEMENT OF SIGNIFICANCE: In this study, a new type of rapamycin-loaded hybrid tissue-engineered vascular graft (RM-HTEV) was fabricated using electrospinning technology. The unique hybrid bi-layer structure endowed the RM-HTEV with multi-functionality: the exterior rapamycin-loaded electrospun PCL nanofibrous layer enhanced the mechanical properties of the graft and possessed drug releasing property; the interior decellularized aorta layer with porous structure could facilitate cell proliferation and migration. In in vivo implantation experiment, RM-HTEV exhibited satisfying long-term patency rate and significantly inhibited intimal hyperplasia without impairing re-endothelialization and M2 macrophage polarization. This strategy is expected to be a promising strategy for developing bioactive small-diameter vascular grafts with great clinical translational potential.

Clinical Outcomes Following Implantation of Thin-Strut, Bioabsorbable Polymer-Coated, Everolimus-Eluting SYNERGY Stents

Background:

The thin-strut SYNERGY stent has an abluminal everolimus-eluting bioabsorbable polymer coating designed to facilitate vascular healing and reduce risk of stent thrombosis. In the multicenter, randomized EVOLVE II trial (The EVOLVE II Clinical Trial to Assess the SYNERGY Stent System for the Treatment of Atherosclerotic Lesion[s]), SYNERGY was noninferior to the durable polymer PROMUS Element Plus everolimus-eluting stent for the primary end point of 1-year target lesion failure. Longer-term clinical follow-up will support the relative efficacy and safety of SYNERGY.

Methods:

Patients with ≤3 native coronary lesions (reference vessel diameter ≥2.25–≤4.00 mm; length ≤34 mm) in ≤2 major epicardial vessels were randomized 1:1 to SYNERGY (N=838) or PROMUS Element Plus (N=846). EVOLVE II included a Diabetes substudy which pooled patients with diabetes mellitus from the randomized controlled trial (n=263) and from a sequential, single-arm substudy (N=203).

Results:

The 5-year target lesion failure rate was 14.3% for SYNERGY and 14.2% for PROMUS Element Plus ( P =0.91). Landmark analysis demonstrated similar rates of target lesion failure from discharge to 1-year ( P =0.90) and from 1 to 5 years ( P =0.94). Definite/probable stent thrombosis was infrequent in both arms (SYNERGY 0.7% versus PROMUS Element Plus 0.9%; P =0.75). There were no significant differences in the rates of cardiac death, myocardial infarction, or revascularization. Among patients with diabetes mellitus, the target lesion failure rate to 1-year was noninferior to a prespecified performance goal and to 5 years was 17.0%.

Conclusions:

SYNERGY demonstrated comparable outcomes to PROMUS Element Plus, with low rates of stent thrombosis and adverse events through 5 years of follow-up. Five-year clinical outcomes were favorable in patients with diabetes mellitus. These data support the long-term safety and effectiveness of SYNERGY in a broad range of patients.

Clinical Trial Registration:

URL: https://www.clinicaltrials.gov . Unique identifier: NCT01665053.

Multi-objective optimisation of material properties and strut geometry for poly(L-lactic acid) coronary stents using response surface methodology

Coronary stents for treating atherosclerosis are traditionally manufactured from metallic alloys. However, metal stents permanently reside in the body and may trigger undesirable immunological responses. Bioresorbable polymer stents can provide a temporary scaffold that resorbs once the artery heals but are mechanically inferior, requiring thicker struts for equivalent radial support, which may increase thrombosis risk. This study addresses the challenge of designing mechanically effective but sufficiently thin poly(L-lactic acid) stents through a computational approach that optimises material properties and stent geometry. Forty parametric stent designs were generated: cross-sectional area (post-dilation), foreshortening, stent-to-artery ratio and radial collapse pressure were evaluated computationally using finite element analysis. Response surface methodology was used to identify performance trade-offs by formulating relationships between design parameters and response variables. Multi-objective optimisation was used to identify suitable stent designs from approximated Pareto fronts and an optimal design is proposed that offers comparable performance to designs in clinical practice. In summary, a computational framework has been developed that has potential application in the design of high stiffness, thin strut polymeric stents.

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.

Clinical impact of complex percutaneous coronary intervention in patients with coronary artery disease

For the revascularization of patients with clinical and anatomical complexities, several technical skills are often required. However, the prognostic effect of complex percutaneous coronary intervention (C-PCI) on the clinical outcomes is not well known. The aim of this study was to investigate the relationship between the C-PCI and mid-term clinical outcomes. We assessed 1062 patients who underwent PCI with newer-generation drug-eluting stent and stratified the patients according to whether they had complex PCI (C-PCI, n = 358) or non-complex PCI (non-C-PCI, n = 704). C-PCI was defined as a procedure with at least 1 of the following features: 3 vessels treated, ≥ 3 stents per vessel implanted, ≥ 3 lesions treated, use of a 2-stent technique, the total stent length per vessel > 60 mm, chronic total occlusion, unprotected left main coronary artery stenting, and rotational atherectomy use. All-cause death and major adverse cardiac and cerebrovascular events (MACCE; cardiovascular death, non-fatal myocardial infarction, and non-fatal ischemic stroke) were evaluated. The median follow-up period was 1.9 (0.8-3.0) years. The baseline SYNTAX score was significantly higher in the C-PCI group than in the non-C-PCI group [20 (14-27) vs. 10 (6-17), p < 0.001]. Kaplan-Meier analysis showed that the cumulative incidences of all-cause death (log-rank p = 0.12) and MACCE (log-rank p = 0.64) did not differ between the two groups. On multivariable Cox analysis, C-PCI did not adversely affect the clinical outcomes. Despite a high rate of anatomically complex coronary lesions, the patients who underwent C-PCI had comparable "hard" clinical outcomes with those of non-C-PCI.

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.

Duration of dual antiplatelet therapy after percutaneous coronary intervention with drug-eluting stent: systematic review and network meta-analysis

OBJECTIVE

To evaluate the efficacy and safety of standard term (12 months) or long term (>12 months) dual antiplatelet therapy (DAPT) versus short term (<6 months) DAPT after percutaneous coronary intervention (PCI) with drug-eluting stent (DES).

DESIGN

Systematic review and network meta-analysis.

DATA SOURCES

Relevant studies published between June 1983 and April 2018 from Medline, Embase, Cochrane Library for clinical trials, PubMed, Web of Science, ClinicalTrials.gov, and Clinicaltrialsregister.eu.

REVIEW METHODS

Randomised controlled trials comparing two of the three durations of DAPT (short term, standard term, and long term) after PCI with DES were included. The primary study outcomes were cardiac or non-cardiac death, all cause mortality, myocardial infarction, stent thrombosis, and all bleeding events.

RESULTS

17 studies (n=46 864) were included. Compared with short term DAPT, network meta-analysis showed that long term DAPT resulted in higher rates of major bleeding (odds ratio 1.78, 95% confidence interval 1.27 to 2.49) and non-cardiac death (1.63, 1.03 to 2.59); standard term DAPT was associated with higher rates of any bleeding (1.39, 1.01 to 1.92). No noticeable difference was observed in other primary endpoints. The sensitivity analysis revealed that the risks of non-cardiac death and bleeding were further increased for ≥18 months of DAPT compared with short term or standard term DAPT. In the subgroup analysis, long term DAPT led to higher all cause mortality than short term DAPT in patients implanted with newer-generation DES (1.99, 1.04 to 3.81); short term DAPT presented similar efficacy and safety to standard term DAPT with acute coronary syndrome (ACS) presentation and newer-generation DES placement. The heterogeneity of pooled trials was low, providing more confidence in the interpretation of results.

CONCLUSIONS

In patients with all clinical presentations, compared with short term DAPT (clopidogrel), long term DAPT led to higher rates of major bleeding and non-cardiac death, and standard term DAPT was associated with an increased risk of any bleeding. For patients with ACS, short term DAPT presented similar efficacy and safety with standard term DAPT. For patients implanted with newer-generation DES, long term DAPT resulted in more all cause mortality than short term DAPT. Although the optimal duration of DAPT should take personal ischaemic and bleeding risks into account, this study suggested short term DAPT could be considered for most patients after PCI with DES, combining evidence from both direct and indirect comparisons.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42018099519.

Drug-eluting or bare-metal stents for percutaneous coronary intervention: a systematic review and individual patient data meta-analysis of randomised clinical trials

BACKGROUND

New-generation drug-eluting stents (DES) have mostly been investigated in head-to-head non-inferiority trials against early-generation DES and have typically shown similar efficacy and superior safety. How the safety profile of new-generation DES compares with that of bare-metal stents (BMS) is less clear.

METHODS

We did an individual patient data meta-analysis of randomised clinical trials to compare outcomes after implantation of new-generation DES or BMS among patients undergoing percutaneous coronary intervention. The primary outcome was the composite of cardiac death or myocardial infarction. Data were pooled in a one-stage random-effects meta-analysis and examined at maximum follow-up and a 1-year landmark. Risk estimates are reported as hazard ratios (HRs) with 95% CIs. This study is registered in PROSPERO, number CRD42017060520.

FINDINGS

We obtained individual data for 26 616 patients in 20 randomised trials. Mean follow-up was 3·2 (SD 1·8) years. The risk of the primary outcome was reduced in DES recipients compared with BMS recipients (HR 0·84, 95% CI 0·78-0·90, p<0·001) owing to a reduced risk of myocardial infarction (0·79, 0·71-0·88, p<0·001) and a possible slight but non-significant cardiac mortality benefit (0·89, 0·78-1·01, p=0·075). All-cause death was unaffected (HR with DES 0·96, 95% CI 0·88-1·05, p=0·358), but risk was lowered for definite stent thrombosis (0·63, 0·50-0·80, p<0·001) and target-vessel revascularisation (0·55, 0·50-0·60, p<0·001). We saw a time-dependent treatment effect, with DES being associated with lower risk of the primary outcome than BMS up to 1 year after placement. While the effect was maintained in the longer term, there was no further divergence from BMS after 1 year.

INTERPRETATION

The performance of new-generation DES in the first year after implantation means that BMS should no longer be considered the gold standard for safety. Further development of DES technology should target improvements in clinical outcomes beyond 1 year.

FUNDING

Bern University Hospital.