Analysis of 14 trials comparing sirolimus-eluting stents with bare-metal stents

In-Stent Re-Endothelialization Strategies: Cells, Extracellular Matrix, and Extracellular Vesicles

Arterial stenosis caused by atherosclerosis often requires stent implantation to increase the patency of target artery. However, such external devices often lead to in-stent restenosis due to inadequate re-endothelialization and subsequent inflammatory responses. Therefore, re-endothelialization strategies after stent implantation have been developed to enhance endothelial cell recruitment or to capture circulating endothelial progenitor cells. Notably, recent research indicates that coating stent surfaces with biogenic materials enhances the long-term safety of implantation, markedly diminishing the risk of in-stent restenosis. In this review, we begin by describing the pathophysiology of coronary artery disease and in-stent restenosis. Then, we review the characteristics and materials of existing stents used in clinical practice. Lastly, we explore biogenic materials aimed at accelerating re-endothelialization, including extracellular matrix, cells, and extracellular vesicles. This review helps overcome the limitations of current stents for cardiovascular disease and outlines the next phase of research and development.

Incidence and pattern of urgent revascularization in acute coronary syndromes treated with ticagrelor or prasugrel

BACKGROUND

The ISAR-REACT 5 trial compared the efficacy and safety of ticagrelor and prasugrel in patients with ACS managed invasively. The present study sought to investigate the impact of ticagrelor and prasugrel on the incidence and pattern of urgent revascularization in acute coronary syndromes (ACS) patients undergoing percutaneous coronary intervention (PCI).

METHODS AND RESULTS

This post-hoc analysis of the ISAR-REACT 5 trial included all ACS patients who underwent PCI. The primary endpoint for this analysis was the incidence of urgent revascularization at 12-month follow-up. Secondary outcome was the pattern of urgent revascularization procedures (namely, urgent target vessel/non-target vessel revascularization - TVR/NTVR). Among 3,377 ACS patients who underwent PCI, 1,676 were assigned to ticagrelor and 1,701 to prasugrel before PCI. After 12 months, the incidence of urgent revascularization was higher among patients assigned to ticagrelor as compared to prasugrel (6.8% vs. 5.2%; hazard ratio [HR] = 1.32, 95% confidence interval [CI] 1.00-1.75; p = 0.051), mostly attributable to significantly more urgent NTVR in the ticagrelor group (3.8% vs. 2.4%; HR = 1.62 [1.09-2.41]; p = 0.017). The risk of urgent TVR did not differ between treatment groups (3.3% vs. 3.0%; HR = 1.13 [0.77-1.65]; p = 0.546).

CONCLUSIONS

In ACS patients treated with PCI, the cumulative rate of urgent revascularizations after 12 months is higher with ticagrelor compared to prasugrel, due to a significant increase in urgent revascularizations involving remote coronary vessels.

Paclitaxel-Coated Balloon vs Uncoated Balloon for Coronary In-Stent Restenosis: The AGENT IDE Randomized Clinical Trial

Importance

Drug-coated balloons offer a potentially beneficial treatment strategy for the management of coronary in-stent restenosis. However, none have been previously evaluated or approved for use in coronary circulation in the United States.

Objective

To evaluate whether a paclitaxel-coated balloon is superior to an uncoated balloon in patients with in-stent restenosis undergoing percutaneous coronary intervention.

Design, Setting, and Participants

AGENT IDE, a multicenter randomized clinical trial, enrolled 600 patients with in-stent restenosis (lesion length <26 mm and reference vessel diameter >2.0 mm to ≤4.0 mm) at 40 centers across the United States between May 2021 and August 2022. One-year clinical follow-up was completed on October 2, 2023.

Interventions

Participants were randomized in a 2:1 allocation to undergo treatment with a paclitaxel-coated (n = 406) or an uncoated (n = 194) balloon.

Main Outcomes and Measures

The primary end point of 1-year target lesion failure-defined as the composite of ischemia-driven target lesion revascularization, target vessel-related myocardial infarction, or cardiac death-was tested for superiority.

Results

Among 600 randomized patients (mean age, 68 years; 157 females [26.2%]; 42 Black [7%], 35 Hispanic [6%] individuals), 574 (95.7%) completed 1-year follow-up. The primary end point at 1 year occurred in 17.9% in the paclitaxel-coated balloon group vs 28.6% in the uncoated balloon group, meeting the criteria for superiority (hazard ratio [HR], 0.59 [95% CI, 0.42-0.84]; 2-sided P = .003). Target lesion revascularization (13.0% vs 24.7%; HR, 0.50 [95% CI, 0.34-0.74]; P = .001) and target vessel-related myocardial infarction (5.8% vs 11.1%; HR, 0.51 [95% CI, 0.28-0.92]; P = .02) occurred less frequently among patients treated with paclitaxel-coated balloon. The rate of cardiac death was 2.9% vs 1.6% (HR, 1.75 [95% CI, 0.49-6.28]; P = .38) in the coated vs uncoated balloon groups, respectively.

Conclusions and Relevance

Among patients undergoing coronary angioplasty for in-stent restenosis, a paclitaxel-coated balloon was superior to an uncoated balloon with respect to the composite end point of target lesion failure. Paclitaxel-coated balloons are an effective treatment option for patients with coronary in-stent restenosis.

Trial Registration

ClinicalTrials.gov Identifier: NCT04647253.

Intrastent Restenosis: A Comprehensive Review

The primary objective of this paper is to delineate and elucidate the contemporary advancements, developments, and prevailing trajectories concerning intrastent restenosis (ISR). We aim to provide a thorough overview of the most recent developments in this area, covering various aspects such as pathophysiological insights, therapeutic approaches, and new strategies for tackling the complex challenges of ISR in modern clinical settings. The authors have undertaken a study to address a relatively new medical challenge, recognizing its significant impact on the morbidity and mortality of individuals with cardiovascular diseases. This effort is driven by the need to fully understand, analyze, and possibly improve the outcomes of this emerging medical issue within the cardiovascular disease field. We acknowledge its considerable clinical implications and the necessity for innovative methods to mitigate its effects on patient outcomes. Therefore, our emphasis was directed towards elucidating the principal facets of the condition's prevalence, expounding upon the foundational mechanisms underscoring conspicuous restenosis, and delineating the risk factors relevant in shaping the contemporary landscape of diagnostic and therapeutic modalities. This thorough examination aims to provide a comprehensive understanding of the various dimensions of the condition, including epidemiological data, pathophysiological complexities, and clinical considerations critical for evaluating and enhancing current diagnostic and treatment approaches.

High on-aspirin treatment platelet reactivity and restenosis after percutaneous coronary intervention: results of the Intracoronary Stenting and Antithrombotic Regimen-ASpirin and Platelet Inhibition (ISAR-ASPI) Registry

OBJECTIVE

The aim of this study was to assess the association between high on-aspirin treatment platelet reactivity (HAPR) and the subsequent risk of restenosis after percutaneous coronary intervention (PCI) with predominantly drug-eluting stents.

BACKGROUND

The association between HAPR and subsequent risk of restenosis after PCI is unclear.

METHODS

This study included 4839 patients undergoing PCI (02/2007-12/2011) in the setting of the Intracoronary Stenting and Antithrombotic Regimen-ASpirin and Platelet Inhibition (ISAR-ASPI) registry. Platelet function was assessed with impedance aggregometry using the multi-plate analyzer immediately before PCI and after intravenous administration of aspirin (500 mg). The primary outcome was clinical restenosis, defined as target lesion revascularization at 1 year. Secondary outcomes included binary angiographic restenosis and late lumen loss at 6- to 8-month angiography.

RESULTS

The upper quintile cut-off of platelet reactivity measurements (191 AU × min) was used to categorize patients into a group with HAPR (platelet reactivity > 191 AU × min; n = 952) and a group without HAPR (platelet reactivity ≤ 191 AU × min; n = 3887). The primary outcome occurred in 94 patients in the HAPR group and 405 patients without HAPR (cumulative incidence, 9.9% and 10.4%; HR = 0.96, 95% CI 0.77-1.19; P = 0.70). Follow-up angiography was performed in 73.2% of patients. There was no difference in binary restenosis (15.2% vs. 14.9%; P = 0.79) or late lumen loss (0.32 ± 0.57 vs. 0.32 ± 0.59 mm; P = 0.93) between patients with HAPR versus those without HAPR.

CONCLUSIONS

This study did not find an association between HAPR, measured at the time of PCI, and clinical restenosis at 1 year after PCI.

Prevalence, Management and Outcomes of Percutaneous Coronary Intervention for Coronary In-Stent Restenosis: Insights From the France PCI Registry

BACKGROUND

Despite the evolution of stent technology, there is a non-negligible risk of in-stent restenosis (ISR) after Percutaneous coronary intervention (PCI). Large-scale registry data on the prevalence and clinical management of ISR is lacking.

METHODS

The aim was to describe the epidemiology and management of patients with ≥1 ISR lesions treated with PCI (ISR PCI). Data on characteristics, management and clinical outcomes were analyzed for patients undergoing ISR PCI in the France-PCI all-comers registry.

RESULTS

Between January 2014 and December 2018, 31,892 lesions were treated in 22,592 patients, 7.3 % of whom underwent ISR PCI. Patients undergoing ISR PCI were older (68.5 vs 67.8; p < 0.001), and more likely to have diabetes (32.7 % vs 25.4 %, p < 0.001), chronic coronary syndrome or multivessel disease. ISR PCI concerned drug eluting stents (DES) ISR in 48.8 % of cases. Patients with ISR lesions were more frequently treated with DES than drug eluting balloon or balloon angioplasty (74.2 %, 11.6 % and 12.9 %, respectively). Intravascular imaging was rarely used. At 1 year, patients with ISR had higher target lesion revascularization rates (4.3 % vs. 1.6 %; HR 2.24 [1.64-3.06]; p < 0.001).

CONCLUSIONS

In a large all-comers registry, ISR PCI was not infrequent and associated with worse prognosis than non-ISR PCI. Further studies and technical improvements are warranted to improve the outcomes of ISR PCI.

Empagliflozin inhibits neointimal hyperplasia through attenuating endothelial-to-mesenchymal transition via TAK-1/NF-κB pathway

OBJECTIVE

To investigate whether empagliflozin could prevent injury-induced vascular neointimal hyperplasia and to further explore its mechanism.

METHODS

Male C57BL/6J mice were divided into two groups with or without the empagliflozin treatment, and carotid ligation injury was performed to induce neointimal hyperplasia. The injured carotid arteries were collected for Western blotting (WB), histology and immunofluorescence analysis after four weeks. The inflammatory responses were analyzed by qRT-PCR to detect the inflammatory gene mRNA expression. To further explore its mechanism, HUVECs were treated with TGFβ-1 to induce EndMT followed by empagliflozin or vehicle treatment in vitro. A23187 (Calcimycin), an agonist of NF-κB signaling was used in the experiment.

RESULTS

The wall thickness and the neointima area was significantly reduced in the empagliflozin treatment group on day 28 after artery ligation. The Ki-67 positive cells were 28.33 ± 12.66% and 48.83 ± 10.41% in the empagliflozin-treated group and control group, respectively (P < 0.05). The mRNA expression levels of the inflammatory genes and inflammatory cells were decreased in the empagliflozin treatment group, as well as the MMP2 and MMP9. Meanwhile, empagliflozin can significantly reduce the migratory ability of inflammatory-treated HUVECs. The CD31 was increased in the TGFβ1+empagliflozin group, whereas the FSP-1, phosphorylation of TAK-1 (p-TAK-1) and phosphorylation of NF-κB (p- NF-κB) expression level were decreased, compared to the control group without empagliflozin treatment. However, the expression level of FSP-1 and p-NF-κB were reversed after co-treatment with A23187, whereas the (p-TAK-1 expression level was without any significant difference.

CONCLUSION

Empagliflozin inhibits the inflammation-induced EndMT via the TAK-1/NF-κB signaling pathway.

Ten-year patterns of stent thrombosis after percutaneous coronary intervention with new- versus early-generation drug-eluting stents: insights from the DECADE cooperation

INTRODUCTION AND OBJECTIVES

The DECADE cooperation is a pooled analysis of individual patient data from drug-eluting stent (DES) trials with a 10-year follow-up. This analysis reports the risk of definite stent thrombosis (ST) through to 10 years after percutaneous coronary intervention (PCI) in patients treated with early- and new-generation DES.

METHODS

Individual patient data from 5 DES trials with a 10-year follow-up were pooled. The primary endpoint was definite ST up to 10 years after PCI. Patients were divided into 2 groups as per the generation of DES implanted (early and new DES). Individual participant data were analyzed using a 1-stage approach.

RESULTS

We included 9700 patients, 6866 in the new DES group and 2834 in the early DES group. Through to 10 years, definite ST occurred in 69 of 6866 patients treated with new DES and in 91 of 2834 patients treated with early DES (1.0% vs 3.5%, adjusted hazard ratio, 0.32; 95%CI, 0.23-0.45). The rate of definite ST was lower in the new DES group than in the early DES group from 1 to 5 years (rate ratio, 0.14; 95%CI, 0.08-0.26) and from 5 to 10 years (rate ratio, 0.23; 95%CI, 0.08-0.61) after PCI.

CONCLUSIONS

The incidence of definite ST through to 10 years after PCI with new-generation DES was 1%. New-generation DES are associated with a lower 10-year incidence of definite ST than early-generation DES, particularly beyond 1 year after PCI.

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.

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

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

Long-Term Outcomes With Drug-Eluting Balloon for the Treatment of In-Stent Restenosis and De Novo Lesions: The Novara-Biella-Trento (NOBITRE) Registry

Drug-coated balloons (DCBs) have emerged for percutaneous coronary interventions (PCI) of in-stent restenosis or particular anatomical subsets. We provide a real-world analysis of the prognostic determinants and long-term outcomes of patients treated with DCB for any lesion in a comprehensive multicenter registry. The primary study endpoint was the occurrence of major cardiovascular events (MACE: composite of all-cause death, myocardial infarction, and target vessel revascularization) at the longest available follow-up. We included 267 patients (196 treated for in-stent restenosis and 71 for de novo lesions), with a median follow-up of 616 [368–1025] days. MACE occurred in 70 (26.2%) of the patients and related with higher rates of in-stent restenosis (P = .04), longer and more type C lesions ( P = .05 and P = .04). At multivariate Cox-regression, type C lesions emerged as the only independent predictor of MACE (adjusted OR [95% CI] = 1.83[1.13–2.97], P = .014), mainly driven by target vessel revascularization (adjusted OR[95% CI] = 1.78[1.05–2.95], P = .03) not conditioning survival. In-stent restenosis emerged as major determinant of TLF (adjusted OR[95% CI] = 2.59[1.17–5.75], P = .02). DCBs represent a treatment option for any lesion; however, type C and restenotic lesions are associated with an increased risk of MACE and target lesion failure, where the optimal strategies for patients’ selection and lesion preparation are still undefined.

Glycaemic Control in Patients Undergoing Percutaneous Coronary Intervention: What Is the Role for the Novel Antidiabetic Agents? A Comprehensive Review of Basic Science and Clinical Data

Coronary artery disease (CAD) remains one of the most important causes of morbidity and mortality worldwide, and revascularization through percutaneous coronary interventions (PCI) significantly improves survival. In this setting, poor glycaemic control, regardless of diabetes, has been associated with increased incidence of peri-procedural and long-term complications and worse prognosis. Novel antidiabetic agents have represented a paradigm shift in managing patients with diabetes and cardiovascular diseases. However, limited data are reported so far in patients undergoing coronary stenting. This review intends to provide an overview of the biological mechanisms underlying hyperglycaemia-induced vascular damage and the contrasting actions of new antidiabetic drugs. We summarize existing evidence on the effects of these drugs in the setting of PCI, addressing pre-clinical and clinical studies and drug-drug interactions with antiplatelet agents, thus highlighting new opportunities for optimal long-term management of these patients.

Appropriate Surrogate Endpoint in Drug-Coated Balloon Trials for Coronary Artery Diseases

Background

The appropriateness of using late lumen loss (LLL) as a surrogate endpoint was established in drug-eluting stent (DES) studies, but it was less supportive for drug-coated balloon (DCB) trials.

Methods

Studies published until 23 June 2021 were searched from PubMed, EMBASE, Cochrane Library, and ClinicalTrials.gov. The correlation between LLL, MLD (minimal lumen diameter), and %DS (percentage diameter stenosis) and clinical endpoints was evaluated by linear regression. Standardized effect size and its 95% CIs were used to illustrate the difference among LLL, MLD, and %DS.

Results

A total of 24 clinical trials were eligible [16 DCB vs. DES, 7 DCB vs. plain old balloon angioplasty (POBA), and 1 DCB vs. DES vs. POBA]. Thirteen (54.2%) trials used LLL as the primary endpoint. LLL, MLD, and %DS all had significant associations with clinical endpoints. For DCB vs. DES trials, the number of studies that reported inconsistent results between LLL and MLD was 12/16 (75.0%) and between LLL and %DS was 10/15 (66.7%), while in MLD and %DS, it was 1/16 (6.3%). The difference of standardized effect size between LLL and MLD was −0.47 (95% CI, −0.69 to −0.25, p < 0.001) and LLL and %DS was−0.31 (95%CI,−0.43 to−0.20, p < 0.001) while in MLD and %DS, there was no difference, 0.1 (95%CI,−0.02 to 0.22, p = 0.084).

Conclusions

For DCB trials, an appropriate surrogate is associated with the control device. The traditional LLL could be used in the DCB vs. POBA trials. However, MLD/%DS should be considered a more suitable surrogate endpoint when comparing DCB with DES.

Management of in-stent restenosis

In-stent restenosis (ISR) remains the most common cause of stent failure after percutaneous coronary intervention (PCI). Recent data suggest that ISR-PCI accounts for 5-10% of all PCI procedures performed in current clinical practice. This State-of-the-Art review will primarily focus on the management of ISR but will begin by briefly discussing diagnosis and classification. We then move on to detail the evidence base underpinning the various therapeutic strategies for ISR before finishing with a proposed ISR management algorithm based on current scientific data.

＜Editors' Choice＞ Very long-term clinical outcomes after percutaneous coronary intervention for complex vs non-complex lesions: 10-year outcomes following sirolimus-eluting stent implantation

Few studies have reported the long-term outcomes (>10 years) following first-generation drug-eluting stent implantation. In this single-center retrospective study, we investigated the very long-term clinical outcomes after first-generation sirolimus-eluting stent (SES) implantation in patients with complex lesions. The study included 383 consecutive patients who underwent initial SES implantation between July 2004 and January 2006; 84 and 299 of these patients reported a history of percutaneous coronary intervention (PCI) for complex and noncomplex lesions, respectively. Complex PCI was defined as having at least one of the following features: left main trunk PCI, implantation of ≥3 stents, bifurcation lesions with implantation of 2 stents, total stent length >60 mm, or chronic total occlusion. The target lesion revascularization (TLR) rate was significantly higher in the complex PCI than in the noncomplex PCI group (29.4% vs 13.0%, P=0.001), and we observed a significant intergroup difference in the late TLR (>1 year) rates (21.6% vs 9.5%, P=0.008). Late TLR continued over 10 years at a rate of 2.4%/year in the complex PCI and 1.1%/year in the noncomplex PCI group. Cox regression analysis revealed that complex PCI was related to TLR both over 10 years (hazard ratio 2.29, P=0.003) and beyond 1 year (hazard ratio 2.32, P=0.01). Cardiac death was more common in the complex PCI than in the noncomplex PCI group, particularly 4 years after PCI (15.8% vs 7.5%, P=0.031). Sudden death was the major cause of cardiac death beyond 4 years in the complex PCI group. These data indicate that long-term careful follow-up is essential for patients implanted with SES, especially those treated for complex lesions.

Angiogenic factor AGGF1 Blocks Neointimal Formation after Vascular Injury via Interaction with Integrin α7 on Vascular Smooth Muscle Cells

Angiogenic factor AGGF1 (AngioGenic factor with G-patch and FHA (Forkhead-Associated) domain 1) blocks neointimal formation (formation of a new or thickened layer of arterial intima) after vascular injury by regulating phenotypic switching of vascular smooth muscle cells (VSMCs). However, the AGGF1 receptor on VSMCs and the underlying molecular mechanisms of its action are unknown. In this study, we used functional analysis of serial AGGF1 deletions to reveal the critical AGGF1 domain involved in VSMC phenotypic switching. This domain was required for VSMC phenotypic switching, proliferation, cell cycle regulation, and migration, as well as the regulation of cell cycle inhibitors cyclin D, p27, and p21. This domain also contains an RDDAPAS motif via which AGGF1 interacts with integrin α7 (ITGA7), but not α8. In addition, we show that AGGF1 enhanced the expression of contractile markers MYH11, α-SMA, and SM22 and inhibited MEK1/2, ERK1/2, and ELK phosphorylation in VSMCs, and that these effects were inhibited by knockdown of ITGA7, but not by knockdown of ITGA8. In vivo, deletion of the VSMC phenotypic switching domain in mice with vascular injury inhibited the functions of AGGF1 in upregulating α-SMA and SM22, inhibiting MEK1/2, ERK1/2, and ELK phosphorylation, in VSMC proliferation, and in blocking neointimal formation. Finally, we show the inhibitory effect of AGGF1 on neointimal formation was blocked by lentivirus-delivered shRNA targeting ITGA7. Our data demonstrate that AGGF1 interacts with its receptor integrin α7 on VSMCs, and this interaction is required for AGGF1 signaling in VSMCs and for attenuation of neointimal formation after vascular injury.

Diabetes and restenosis

Restenosis, defined as the re-narrowing of an arterial lumen after revascularization, represents an increasingly important issue in clinical practice. Indeed, as the number of stent placements has risen to an estimate that exceeds 3 million annually worldwide, revascularization procedures have become much more common. Several investigators have demonstrated that vessels in patients with diabetes mellitus have an increased risk restenosis. Here we present a systematic overview of the effects of diabetes on in-stent restenosis. Current classification and updated epidemiology of restenosis are discussed, alongside the main mechanisms underlying the pathophysiology of this event. Then, we summarize the clinical presentation of restenosis, emphasizing the importance of glycemic control in diabetic patients. Indeed, in diabetic patients who underwent revascularization procedures a proper glycemic control remains imperative.

Therapeutic MK2 inhibition blocks pathological vascular smooth muscle cell phenotype switch

Vascular procedures, such as stenting, angioplasty, and bypass grafting, often fail due to intimal hyperplasia (IH), wherein contractile vascular smooth muscle cells (VSMCs) dedifferentiate to synthetic VSMCs, which are highly proliferative, migratory, and fibrotic. Previous studies suggest MAPK-activated protein kinase 2 (MK2) inhibition may limit VSMC proliferation and IH, although the molecular mechanism underlying the observation remains unclear. We demonstrated here that MK2 inhibition blocked the molecular program of contractile to synthetic dedifferentiation and mitigated IH development. Molecular markers of the VSMC contractile phenotype were sustained over time in culture in rat primary VSMCs treated with potent, long-lasting MK2 inhibitory peptide nanopolyplexes (MK2i-NPs), a result supported in human saphenous vein specimens cultured ex vivo. RNA-Seq of MK2i-NP-treated primary human VSMCs revealed programmatic switching toward a contractile VSMC gene expression profile, increasing expression of antiinflammatory and contractile-associated genes while lowering expression of proinflammatory, promigratory, and synthetic phenotype-associated genes. Finally, these results were confirmed using an in vivo rabbit vein graft model where brief, intraoperative treatment with MK2i-NPs decreased IH and synthetic phenotype markers while preserving contractile proteins. These results support further development of MK2i-NPs as a therapy for blocking VSMC phenotype switch and IH associated with cardiovascular procedures.

A randomised comparison of coronary stents according to short or prolonged durations of dual antiplatelet therapy in patients with acute coronary syndromes: a pre-specified analysis of the SMART-DATE trial

BACKGROUND

Data on direct comparison between various drug-eluting stents with short duration dual antiplatelet therapy (DAPT) are limited, especially in patients with acute coronary syndrome (ACS).

AIMS

We sought to compare biodegradable polymer biolimus-eluting stents (BP-BES) with durable polymer everolimus-eluting (DP-EES) and zotarolimus-eluting stents (DP-ZES) in patients with ACS according to different durations of DAPT.

METHODS

In the SMART-DATE trial, 2,712 patients with ACS underwent randomisation for allocation of DAPT (6 months [n=1,357] or 12 months or longer [n=1,355]) and type of stent (BP-BES [n=901]), DP-EES [n=904], or DP-ZES [n=907]). The primary endpoint was a composite of cardiac death, myocardial infarction, or stent thrombosis.

RESULTS

At 18 months, the primary endpoint was attained by 2.6% with BP-BES, 2.0% with DP-EES, and 2.1% with DP-ZES (HR 1.29, 95% CI: 0.70-2.39, p=0.42 for BP-BES vs DP-EES and HR 1.23, 95% CI: 0.67-2.26, p=0.50 for BP-BES vs DP-ZES). The treatment effect of BP-BES for the primary endpoint was consistent among patients receiving 6-month DAPT as well as those receiving 12-month or longer DAPT (BP-BES vs. DP-EES, pinteraction=0.48 and BP-BES vs DP-ZES, pinteraction=0.87). After excluding 179 patients (101 in the BP-BES group) who did not receive allocated DES, the per-protocol analysis showed similar results.

CONCLUSIONS

The risk of a composite of cardiac death, myocardial infarction, or stent thrombosis was not significantly different between patients receiving BP-BES versus DP-EES or DP-ZES across a short or prolonged duration of DAPT after ACS.

Thin- versus thick-strut polymer-free biolimus-eluting stents: the BioFreedom QCA randomised trial

BACKGROUND

The BioFreedom drug-coated stent with a stainless steel platform (BF-SS) has been demonstrated to be efficacious in patients at high bleeding risk and receiv-ing only one-month dual antiplatelet therapy.

AIMS

The aim of this study was to evaluate the efficacy of the new BioFreedom Ultra drug-coated stent with a thin-strut cobalt-chromium platform (BF-CoCr) compared to the BF-SS in an all-comers population undergoing percutaneous coronary intervention (PCI).

METHODS

This was a prospective, multicentre, non-inferiority trial. The primary endpoint was in-stent late lumen loss (LLL) as determined by quantitative coronary angiography at nine-month follow-up. Clinical evaluation was performed at one year.

RESULTS

A total of 200 patients were randomised (1:1) to either the BF-CoCr or the BF-SS stent at eight centres in Spain and Denmark. Baseline clinical and lesion characteristics were similar between the groups. Mean age was 66 years and 23% were female. The mean number of stents implanted per patient was 1.5. At nine-month follow-up, mean in-stent LLL was 0.34±0.49 mm in the BF-CoCr group versus 0.29±0.37 mm in the BF-SS group, p=0.005 for non-inferiority. At one year, target lesion failure was similar between the groups (7.3% in BF-CoCr vs 9.3% in the BF-SS group; p=0.60).

CONCLUSIONS

The BF-CoCr was non-inferior to the BF-SS in terms of in-stent LLL at nine months. Larger studies powered for clinical endpoints are warranted to compare the efficacy of this new platform with currently available DES.

Pathological findings after third- and second-generation everolimus-eluting stent implantations in coronary arteries from autopsy cases and an atherosclerotic porcine model

Pathological changes after third-generation drug-eluting stent implantation remain unclear. We compared the tissue responses of coronary arteries after the implantation of third-generation abluminal biodegradable-polymer everolimus-eluting stent (3rd EES) and second-generation durable-polymer EES (2nd EES) using autopsy specimens and an atherosclerotic porcine model. We compared the histology of stented coronary arteries obtained by autopsy performed 1–10 months after 3rd EES (n (number of cases) = 4, stent-implanted period of 3–7 months) and 2nd EES (n (number of cases) = 9, stent-implanted period of 1–10 months) implantations. The ratio of covered stent struts was higher with 3rd EESs than with 2nd EESs (3rd; 0.824 ± 0.032 vs. 2nd; 0.736 ± 0.022, p = 0.035). Low-density lipoprotein receptor knockout minipigs were stented with 3rd or 2nd EES in the coronary arteries and the stented regions were investigated. The fibrin deposition around the 2nd EES was more prominent. Additionally, higher density of smooth muscle cells was confirmed after the 3rd EES implantation. Pathological examination after the 3rd EES demonstrated a combination of less fibrin deposition and more rapid acquisition of well-developed neointima as compared to the 2nd EES at autopsy and the atherosclerotic porcine model.

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

BACKGROUND

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Comparison of Endothelial Dysfunction in Coronary Arteries with Bare Metal and 2nd-Generation Drug-Eluting Stents

Aims: Previous studies suggested that implantation with a 1st-generation DES was associated with coronary endothelial dysfunction, which was associated with Rho-kinase activation. Second-generation drug-eluting stents (DESs) may preserve coronary endothelial function in stented coronary arteries; however, because of methodological limitations, further study is needed to clarify the association between 2 ^nd -generation DESs and coronary endothelial dysfunction.

Methods: We retrospectively analysed the CuVIC trial database, where we identified 112 patients who underwent coronary stenting in the left coronary arteries with either a bare metal stent (BMS, n =53) or 2 ^nd -generation DES ( n =59). We compared vasomotions of target vessels with stents and non-target vessels without stents. Furthermore, we measured the Rho-kinase activation detected in mononucleocytes from aortic and coronary sinus blood.

Results: ACh-induced vasoconstrictive responses of target vessels were not enhanced with a 2 ^nd -generation DES (45±21% vs. 44±20%, P =0.56, paired t -test), but significantly enhanced in the coronary arteries with a BMS (50±18% vs. 42±20%, P =0.002). Rho-kinase activation did not differ between patients with a BMS and 2 ^nd -generation DES. In the target vessels with a BMS, large late lumen loss and acute coronary syndrome (ACS) at the index percutaneous coronary intervention (PCI) were associated with ACh-induced enhanced coronary vasoconstrictive responses.

Conclusions: Evaluation of ACh-induced vasomotion of target vessels comparing with non-target vessels revealed that 2 ^nd -generation DESs were not associated with coronary endothelial dysfunction in target vessels, nor activation of Rho-kinase in the coronary sinus blood 6-8 months after stenting.

In vivo evaluation of a pro-healing polydopamine coated stent through an in-stent restenosis rat model

Drug-eluting stents have demonstrated efficiency in in-stent restenosis (ISR) but induced a risk of late acute thrombosis by delaying strut re-endothelialization. Polydopamine (PDA), a biocompatible polymer inspired from adhesive proteins of mussels, has been reported to promote endothelial cell (EC) proliferation while limiting SMC proliferation in vitro, thus suggesting the pro-healing potential. This study aimed at evaluating in vivo the impact of the pro-healing PDA-coated stent on ISR and on the quality of the strut re-endothelialization in a rat model. PDA-coated stents demonstrated a significant reduction in ISR in vivo compared to bare metal stents (ratio neointima/media = 0.48 (±0.26) versus 0.83 (±0.42), p < 0.001). Western blot analyses identified a trend towards an increased activation of p38 MAPK phosphorylation and its anti-proliferative effects on vascular SMC that could explain the results observed in morphological analyses. This bioinspired and biocompatible polydopamine layer could intrinsically limit ISR. In addition, according to its latent reactivity, PDA offers the possibility to immobilize some relevant drugs on the PDA-functionalized stent to provide potential synergistic effects.

Impact of Neointimal Condition and Platelet Reactivity on Intrastent Thrombus at Long-Term Follow-up After 2nd- and 3rd-Generation Drug-Eluting Stent Implantation - Insights From a Coronary Angioscopy and Pharmacodynamic Study

BACKGROUND

Although the incidence of very late stent failure (VLSF) is reduced with newer generation drug-eluting stent (DES), the mechanism of VLSF has not been fully explored.Methods and Results:This study evaluated both local vascular healing using coronary angioscopy and systemic factors determined by platelet reactivity at long-term follow-up after 2nd- and 3rd-generation DES implantation in patients with acute coronary syndrome. Coronary angioscopy was performed to assess neointimal coverage (NIC), yellow color (YC) grade and presence of thrombus. The obtained findings were compared with 2nd- and 3rd-DES. Platelet aggregation was assessed by light transmittance aggregometry. 100 consecutive patients were prospectively enrolled: 2nd- (n=50) and 3rd-DES (n=50). 3rd-DES patients had significantly higher NIC grade and lower YC grade compared with 2nd-DES. The presence of thrombus was tended to be lower with 3rd-DES than with 2nd-DES (8% vs. 18%, P=0.11). Patients with thrombus had significantly higher maximum platelet aggregation and higher prevalence of high on-treatment platelet reactivity (HPR) than those without thrombus. Multivariable analysis showed stent strut exposure and HPR as independent predictors of thrombus.

CONCLUSIONS

Newer generation DES contribute to better vascular healing depending on the degree of neointimal coverage. In addition to local factors at the stented lesion, systemic factors such as degree of platelet reactivity might also contribute to VLSF.

The birth, decline, and contemporary re-emergence of endovascular brachytherapy for prevention of in-stent restenosis

Despite the advent of drug-eluting stents and dual antiplatelet therapy in the interventional management of cardiovascular disease, restenosis rates remain high with significant sequelae. Endovascular brachytherapy-popular in the 1990s and early 2000s-has recently resurfaced as a cost-effective treatment option. In this work, we outline the history of endovascular brachytherapy starting with its earliest promise in the 1990s. We discuss the development of drug-eluting stents and dual antiplatelet strategies and their impact on the perceived benefit of endovascular brachytherapy. For the contemporary era, we propose novel roles for endovascular brachytherapy in complex coronary artery disease and in high-risk patients managed with drug-eluting stents. We discuss the impetus for reducing the requirement and duration of dual antiplatelet therapy using endovascular brachytherapy. We also review innovative opportunities for endovascular brachytherapy after bare-metal stent placement in both coronary and noncoronary territories and offer economic arguments in favor of endovascular brachytherapy. Trials of endovascular brachytherapy in these regimes are merited.

Safety and performance of everolimus-eluting stents comprising of biodegradable polymers with ultrathin stent platforms

BACKGROUND

The registry investigated clinical outcomes after 12 months of implantation of ultra-thin strut (60 µm) biodegradable polymer-coated Tetrilimus everolimus-eluting stents (EES; Sahajanand Medical Technologies Pvt. Ltd., Surat, India) in patients with atherosclerotic coronary lesions. Additionally, sub-group analysis was performed to evaluate outcomes of ultra-long (44/48 mm) Tetrilimus EES in patients with long lesions.

METHODS

This was an observational, single-center, single-arm and investigator-initiated retrospective registry. In this all-comers registry, patients who underwent implantation of Tetrilimus EES for treatment of coronary artery disease during routine clinical practice between February-2016 and August-2016 at tertiary care center of India were included. Primary endpoint was occurrence of any major adverse cardiac event (MACE) up to 12 months' follow-up. MACE was a composite of cardiac death, myocardial infarction (MI), and target lesion revascularization (TLR). Similar endpoints were observed in sub-group patients.

RESULTS

Total 766 stents were implanted to treat 695 lesions in 558 patients. Of treated lesions, 11.4% lesions were type B2 and 78.3% were type C lesions. In sub-group analysis of 143 patients, a total of 155 long coronary lesions were intervened successfully with only one stent been implanted per lesion. At 12 months' follow-up, four (0.7%) cases of cardiac death, eight (1.4%) of MI, and two (0.4%) of TLR were reported, resulting in a 2.5% rate of MACE. The MACE rate was 2.8% in sub-group patients.

CONCLUSIONS

Twelve months' clinical data demonstrated favorable safety and excellent performance of Tetrilimus EES in high-risk patients and complex coronary lesions in routine clinical practice and also in patients with ultra-long lesions.

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

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

Long-term clinical outcomes after a percutaneous coronary intervention with a drug-eluting stent in patients with unprotected left main coronary artery disease excluded from clinical trials

BACKGROUND

Major randomized clinical trials assessing clinical outcomes in patients who underwent a percutaneous coronary intervention (PCI) for left main coronary artery disease excluded some high-risk subsets. Whether the effectiveness and safety of a percutaneous approach in this group of patients are comparable with those observed in clinical trials is unclear. We aimed to explore the long-term outcomes of contemporary drug-eluting stent (DES)-based revascularization for left main coronary artery disease in patients presenting with one or more clinical or angiographic characteristics who would have precluded inclusion in randomized trials.

PATIENTS AND METHODS

Between April 2003 and December 2011, 340 consecutive patients with unprotected left main coronary artery stenosis of at least 50% who underwent successful PCI with DES at Sejong General Hospital (Bucheon, Republic of Korea) were included in this retrospective study. Patients were classified into the exclusion group (group E; n=120) and the inclusion group (group I; n=220) according to the prespecified inclusion and exclusion criteria utilized in clinical trials.

RESULTS

During the median follow-up of 86 (52-114) months, major adverse cardiac or cerebrovascular events occurred in 69 (31.4%) patients in group I and 46 (38.3%) patients in group E (P=0.155). In the propensity score-matched population, group E was not associated with a higher incidence of major adverse cardiac or cerebrovascular events (hazard ratio: 1.42, 95% confidence interval: 0.76-2.65, P=0.758). Definite or probable stent thrombosis occurred in five patients of group I, with no cases in group E.

CONCLUSION

In our real-world registry, about a third of patients who underwent PCI for unprotected left main coronary artery stenosis had one or more high-risk characteristics or comorbid conditions that represent exclusion criteria of previous randomized trials. PCI using DES is feasible in these patients.

Elderly Medication Adherence Intervention Using the My Interventional Drug-Eluting Stent Educational App: Multisite Randomized Feasibility Trial

BACKGROUND

A lifesaving treatment for myocardial infarction is the placement of a stent in a closed or obstructed coronary artery. The largest modifiable risk factor after receiving a stent is medication adherence to Dual AntiPlatelet Therapy, a combination of P2Y12 inhibitors and aspirin.

OBJECTIVE

This study aimed to determine the acceptability of a protocol and an intervention using the My Interventional Drug-Eluting Stent Educational App (MyIDEA) and to evaluate medication adherence using the proportion of days covered (PDC) and platelet activation tests in a multisite randomized controlled trial.

METHODS

Potential participants who received a post percutaneous coronary intervention (PCI) procedure with a drug-eluting stent were approached. All patients older than 50 years and who spoke English were recruited. Participants were recruited, baseline demographics were collected, and the Hospital Anxiety and Depression Scale (HADS), Rapid Estimate of Adult Literacy in Medicine-Short Form, Burden-Benefit questionnaire, 36-Item Short Form Health Survey, and PCI knowledge questionnaire were administered. Block randomization was used to randomize participants to either usual care or MyIDEA supplementation. MyIDEA is a personalized educational intervention based on the Kolb experiential learning theory using patient narratives for education. During the visits, participants' blood was collected to measure platelet suppression from medication. During the second and third encounters, the Morisky medication adherence score and cardiology outcomes were measured. The study was conducted at the University of Illinois Hospital and John H Stroger Jr Cook County Hospital with appropriate ethical approvals. Platelet suppression was measured through aspirin reactive units and P2Y12 reactive units. Medication adherence was measured using the PDC. The analysis team was blinded to the participants' group membership. The primary outcome was a feasibility analysis of recruitment and retention.

RESULTS

The mean age of participants was 60.4 years (SD 7.1); the majority of patients were black and non-Hispanic. The majority of patients' reading levels were seventh grade or above, and they were not very familiar with other electronic devices for information and communication. The number of control subjects was 21, and the number of participants in the interventional arm was 24. The interventional group was able to use MyIDEA in both the hospital and outpatient setting. However, there was no significant difference in platelet suppression or medication adherence between groups. There were also differences between the groups in terms of depression and anxiety, initially, as measured by HADS. No documented adverse event associated with the intervention was found.

CONCLUSIONS

Elderly patients are willing to use tablet devices to be educated about health conditions. Additional studies are required to measure the effectiveness and determine the most suitable timing and location for patient education.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04439864; https://clinicaltrials.gov/ct2/show/NCT04439864.

Antithrombotic Therapy in Patients With Atrial Fibrillation and Coronary Artery Disease Undergoing Percutaneous Coronary Intervention

AIM

The objective of this article is to review the contemporary literature on the use of antithrombotic therapy in patients with atrial fibrillation (AF) and coronary artery disease after undergoing percutaneous coronary intervention (PCI). Special consideration was given to the type and duration of therapy, treatment strategies for the elderly (≥65 years of age), and strategies to reduce bleeding.

METHODS

Relevant studies were searched through MEDLINE/PubMed, Web of Science, Cochrane Library, ClinicalTrials.gov, and Google Scholar. Of the 236 publications retrieved, 76 were considered relevant including 35 randomized controlled trials, 17 meta-analyses, 16 observational studies, and 8 published major guidelines.

RESULTS

Most trials, meta-analyses, and guidelines support 1 month of triple therapy (TT) with an oral anticoagulant (OAC), dual antiplatelet agents (DAPT) with aspirin (ASA)/clopidogrel, and, afterward, dual therapy (DT) with OAC and single antiplatelet agent for an additional 11 months, or alternatively DT alone for 12 months after PCI. Individual consideration is given to the risk and impact of stent thrombosis (ST), thromboembolism, and bleeding. Several trials and meta-analyses have also suggested that shorter DAPT duration (≤6 months) may be safer than longer therapy (≥6 months) when weighing the risk of bleeding with ischemic outcomes, especially with newer generation drug-eluting stents. The selective use of proton-pump inhibitors in patients prone to gastrointestinal bleeding who are subjected to prolonged exposure with TT or DT may be beneficial. In the elderly, the risk of bleeding from TT, compared with DT, outweighs the benefit of reducing ischemic events.

CONCLUSIONS

In conclusion, tailoring therapy to the individual patient is recommended considering the ischemic and bleeding risk as well as the risk of thromboembolism. For most patients with AF, 1 month of TT and subsequently DT for additional 11 months are recommended.

Factors Associated With the Use of Bare Metal Stents in Patients With ST Elevation Myocardial Infarction

BACKGROUND

Drug eluting stents (DES) are used in the majority of patients undergoing percutaneous coronary intervention (PCI). Factors associated with the use of bare metal stents (BMS) for patients undergoing primary PCI for ST elevation myocardial infarction (STEMI) have not been adequately explored. The objective of this study was to evaluate factors associated with BMS use in STEMI patients undergoing primary PCI.

METHODS

Patients undergoing primary PCI for STEMI between January 2008 and February 2015 were retrospectively identified. Patients who received both a DES and BMS were included in the DES group and patients receiving balloon angioplasty only were excluded. Baseline demographics, angiographic variables, procedure related variables and in-hospital events were collected. Multivariate analysis was performed to identify factors associated with BMS use.

RESULTS

Eight hundred and sixty-five patients underwent primary PCI for STEMI during the study period. Seventy-two patients (8.3%) received balloon angioplasty only and were excluded, yielding 793 patients for the study cohort. Three hundred fifty-two patients (44%) received BMS and 441 patients (56%) received DES. Patients receiving DES had a higher prevalence of diabetes mellitus, prior myocardial infarction, prior PCI, left anterior descending artery culprit location and Medicaid Insurance compared to those receiving BMS. Patients receiving BMS had a higher prevalence of cardiogenic shock and right coronary artery culprit location. Unadjusted in-hospital mortality was significantly higher for patients receiving BMS compared to patients receiving DES, 11.1% vs 3.2%, respectively, p < 0.0001. Multivariate predictors of BMS use were cardiogenic shock (OR 30.3; 95% CI 11.25 to 81.73) and diabetes mellitus (OR 2.99; 95% CI 1.04 to 8.64).

CONCLUSION

In a contemporary series of patients undergoing primary PCI for STEMI, BMS were used in 44% of patients and independent factors associated with BMS use were cardiogenic shock and diabetes mellitus.

Device profile of the Resolute Onyx Zotarolimus eluting coronary stent system for the treatment of coronary artery disease: overview of its safety and efficacy

Introduction: The increasing complexity of patients undergoing percutaneous coronary intervention (PCI) regarding both coronary anatomy and comorbidities requires dedicated devices. The Resolute Onyx (R-Onyx, Medtronic, CA, USA) stent is a novel durable polymer zotarolimus-eluting stent (ZES) promising better deliverability, increased radiopacity and lower thrombogenicity.Areas covered: In this review, we discuss device features, preclinical evidence, and clinical studies including patients treated with R-Onyx. The BIONYX and Onyx ONE studies were two major landmark trials demonstrating non-inferiority of R-Onyx as compared to other latest generation devices. We also elaborate on alternative innovations in drug-eluting stent (DES) technology and how R-Onyx fits into this field.Expert opinion: R-Onyx is designed to address the challenges of contemporary PCI, but evidence on its clinical performance is largely derived from studies on older generation devices from the ZES family. Nonetheless, all clinical studies on R-Onyx consistently show excellent outcomes, with particularly low rates of stent thrombosis, making it a promising candidate for short dual antiplatelet regimens. In addition, R-Onyx is available with a wide range of stent diameters allowing accurate sizing for both very small and very large coronary vessels.

IRF-1 mediates the suppressive effects of mTOR inhibition on arterial endothelium

AIMS

Mammalian target of rapamycin (mTOR) inhibitors used in drug-eluting stents (DES) to control restenosis have been found to delay endothelialization and increase incidence of late-stent thrombosis through mechanisms not completely understood. We revealed that mTOR inhibition (mTORi) upregulated the expression of cell growth suppressor IRF-1 in primary human arterial endothelial cells (HAEC). This study aimed to examine how mTOR-regulated IRF-1 expression contributes to the suppressive effect of mTORi on arterial endothelial proliferation.

METHODS AND RESULTS

Western blotting, quantitative PCR, and a dual-luciferase reporter assay indicated that mTOR inhibitors rapamycin and torin 1 upregulated IRF-1 expression and increased its transcriptional activity. IRF-1 in turn contributed to the suppressive effect of mTORi by mediating HAEC apoptosis and cell cycle arrest in part through upregulation of caspase 1 and downregulation of cyclin D3, as revealed by CCK-8 assay, Annexin V binding assay, measurement of activated caspase 3, BrdU incorporation assay, and matrigel tube formation assay. In a mouse model of femoral artery wire injury, administration of rapamycin inhibited EC recovery, an effect alleviated by EC deficiency of IRF-1. Chromatin immunoprecipitation assay with HAEC and rescue expression of wild type or dominant-negative IRF-1 in EC isolated from Irf1^-/- mice confirmed transcriptional regulation of IRF-1 on the expression of CASP1 and CCND3. Furthermore, mTORi activated multiple PKC members, among which PKCζ was responsible for the growth-inhibitory effect on HAEC. Activated PKCζ increased IRF1 transcription through JAK/STAT-1 and NF-κB signaling. Finally, overexpression of wild type or mutant raptor incapable of binding mTOR indicated that mTOR-free raptor contributed to PKCζ activation in mTOR-inhibited HAEC.

CONCLUSIONS

The study reveals an IRF-1-mediated mechanism that contributes to the suppressive effects of mTORi on HAEC proliferation. Further study may facilitate the development of effective strategies to reduce the side effects of DES used in coronary interventions.

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.

Analysis of Vascular Mechanical Characteristics after Coronary Degradable Stent Implantation

PURPOSE

To explore the effect of vascular stress changes on endothelial function recovery and vascular restenosis inhibition, under the condition of dynamic degradation process of the degradable stent.

METHODS

Fitting the material parameters of the hyperelastic vascular constitutive relationship, the stress distribution of the intima of the blood vessel before the stent was implanted and during the dynamic degradation was calculated by numerical simulation. In vitro culture experiments were carried out, and the stretch ratios of the silicone chamber were set to 0%, 5%, 10%, and 15%, respectively, to simulate the effects of different degradation stages on the growth state of endothelial cells.

RESULTS

After the stent was completely degraded, the circumferential intimal stress (strain) of the vessel was recovered to 0.137 MPa, 5.5%, which was close to the physiological parameters (0.122 MPa, 4.8%) before stent implantation. In vitro experiments showed that the endothelial cell survival rate was the highest under the condition of circumferential stress (strain) of 0.1 MPa, 5%, and all adhesion growth could be achieved.

CONCLUSIONS

With the occurrence of degradation process of the stent, the circumferential stress (strain) of the intima was recovered to a range close to physiological parameters, which promotes the growth of endothelial cells. The recovery of intimal function can effectively inhibit the process of vascular restenosis. The results can provide a theoretical basis and experimental platform for the study of coronary intervention for the treatment of vascular restenosis.

Time Course of Reendothelialization with Polyzene-F Nanocoated Cobra PzF™ Coronary Stent on Rabbit Iliac Arteries

PURPOSE

Evaluation of reendothelialization with a new thin struts cobalt chromium alloy stent coated with a nano-layer of Polyzene™-F (PzF) in a rabbit iliac artery model.

METHODS

Fifteen stented external rabbit iliac arteries were harvested at Day 7 for electron microscopy analysis following Cobra PzF stents implantation to assess reendothelialization and compare to historical data. Ten additional rabbits were used to assess time course of reendothelialization at 3 and 5 days.

RESULTS

At Day 7, almost complete coverage of endothelial cells was observed with a coverage of 99.54 ± 0.25% of the stented area. No thrombus area was noted. At Day 3, more than half of examined pieces was reendothelialized and reached 78.30 ± 3.7% at Day 5 (p < .01 between each group). All stents were well expanded against the arterial wall and no struts were mal-apposed.

CONCLUSIONS

Reendothelialization was rapid and complete at Day 7. This is the fastest reendothelization process after stenting in this model. No stent occlusion was observed.

Three-year major clinical outcomes of phosphorylcholine polymer- vs biolinx polymer-zotarolimus-eluting stents: A propensity score matching study

There are limited long-term outcome data comparing BioLinx polymer (B)-zotarolimus-eluting stents (ZES) with phosphorylcholine polymer (P)-ZES. The aim of this study was to compare the efficacy and safety of B-ZES with P-ZES in patients who underwent percutaneous coronary intervention (PCI) during a 3-year follow-up period.One thousand two hundred fifty four patients who underwent PCI with P-ZES (Endeavor [ZES-E] or Endeavor sprint [ZES-S], n = 356) or B-ZES (Endeavor resolute [ZES-R] or Resolute Integrity [ZES-I], n = 889) were enrolled. The primary endpoint was major adverse cardiac events (MACE); the composite of total death, non-fatal myocardial infarction (MI), target lesion revascularization (TLR), target vessel revascularization (TVR), non-target vessel revascularization (Non-TVR), and the secondary endpoint was stent thrombosis (ST).After PSM, 2 propensity-matched (PSM) groups (275 pairs, n = 550, C-statistic = 0.730) were generated. During the 3-year follow-up period, the cumulative incidence of MACE (hazard ratio [HR], 1.525; 95% confidence interval [CI], 0.920-2.526; P = .101) and ST (HR, 1.248; 95% CI, 0.335-4.4649; P = .741) were similar between P-ZES and B-ZES after PSM. However, TLR rate was significantly higher in ZES-S than ZES-I (11.3% vs 3.8%, log rank P = .029) and TVR rate was higher in ZES-S than ZES-R (14.1% vs 4.8%, log rank P = .025).In this single-center, all-comer registry, despite different polymers, P-ZES, and B-ZES showed comparable safety and efficacy during a 3-year follow-up period after PCI.

One-Year Follow-Up Results From the Observational, Multicenter, Prospective, and Controlled Registry: The WALTZ All-Comers Study

The aim of this study was to evaluate 1-year follow-up results in an all “comers” population treated with a new cobalt chromium bare-metal stent (BMS) design. Since August 2016 to March 2017, 201 (9.7% of screening population) consecutive patients undergoing coronary stent implantation in 11 centers in Argentina were prospectively included in our registry. The inclusion criteria were multiple-vessel disease and/or unprotected left main disease, acute coronary syndromes (ACS) with at least one severe (⩾70%) stenosis in any of major epicardial vessel. In-stent restenosis, protected left main stenosis, or impossibility to receive dual-antiplatelet therapy was an exclusion criterion. Major adverse cardiac events (MACE) were the primary endpoint and included cardiac death, myocardial infarction (MI), and target lesion revascularization (TLR); also, all components of the primary endpoint were separately analyzed. Completeness of revascularization was analyzed as post hoc data using residual SYNTAX or ERACI risk scores. Demographic characteristics showed that 6.5% of patients were very elderly, 22.5% have diabetes, 47% have multiple-vessel disease, 67% have ACS, and 32% have ST elevation MI. At a mean of 376 ± 18.1 days of follow-up, MACE was observed in 10.4% of patients: death + MI + cardiovascular accident (CVA) in 3% (6 of 201) and cardiac death + MI + CVA in 1.5% (3 of 201). Residual ERACI score ⩽5 was associated with 98% of event-free survival (P < .04). In conclusion, this prospective, multicenter, and observational all-comers registry with this novel BMS design showed a low incidence of adverse events at 1 year mainly due to coronary restenosis.

Comparison between the Outcomes of Using Biodegradable-Polymer Drug-Eluting Stents and Those of Using Durable-Polymer Drug-Eluting Stents in Acute Coronary Syndrome Patients Undergoing Percutaneous Coronary Intervention

BACKGROUND:

Many randomised control studies showed that percutaneous coronary interventions using biodegradable-polymer drug-eluting stents (DES) offer a safe and effective alternative to durable-polymer DES. However, not many studies have discussed its use in the setting of acute coronary syndromes.

AIM:

We aim to compare the biodegradable-polymer DES with durable-polymer DES when it comes to reducing the incidence of non-ST elevation acute coronary syndrome (NSTEACS) associated with adverse events.

METHODS:

We enrolled 205 patients presenting with NSTEACS and a TIMI risk score ≥ 3 in this study and divided them into two groups, group A and group B. Biodegradable-polymer DESs were exclusively used in group A, while durable-polymer DESs were used in group B. Major adverse events were reported in both groups during the hospital stay and patients were followed-up for 1 year.

RESULTS:

In our patients, we intervened on 390 diseased segments in a total of 360 vessels. After intervention, TIMI 0 was achieved in 0.97%, TIMI 1 in 1.46%, TIMI 2 in 2.45%, and TIMI 3 in 95.12% of the treated segments (P-value= 0.677). We implanted 121 biodegradable-polymer DESs and 146 durable-polymer DESs. Clinical success was achieved in 95.12% of our cases. We had 55 patients who needed repeated coronary angiography within 1 year (15 patients treated with biodegradable-polymer DES and 24 patients treated with durable-polymer DES). Eighteen patients experienced angina pains (8 patients treated with biodegradable-polymer DES and 10 patients treated with durable-polymer DES). Only 5 patients needed TLR (2 patients treated with biodegradable-polymer DES and 3 patients treated with durable -polymer DES) (P-value = 0.591), three of them had a myocardial infarction with documented angiographic evidence of significant in-stent restenosis (1 patient treated with biodegradable-polymer DES and 2 patients treated with durable-polymer DESs).

CONCLUSION:

Biodegradable-polymer DES represents a comparable alternative to durable-polymer DES in the setting of acute coronary syndromes.

Disparities In The Use Of Drug-eluting Stents For Diabetic Patients With ST-elevation Acute Myocardial Infarction Assisted In the Public versus Private Network - VICTIM Register

BACKGROUND

Primary angioplasty (PA) with placement of either bare metal or drug-eluting stents (DES) represents the main strategy in the treatment of ST-elevation myocardial infarction (STEMI). Diabetic patients, however, represent a special population in STEMI, with high rates of restenosis and unfavorable clinical outcomes, and with the use of DES, level of evidence A and indication class II, being indicated to reduce these damages.

OBJECTIVES

To evaluate the DES rate of use in patients with STEMI and in the subgroup of diabetics assisted in the public versus private health network in Sergipe.

METHODS

This is a population-based, cross-sectional study with a quantitative approach using the data from the VICTIM Register. These were collected in the only four hospitals with capacity to perform PA in Sergipe, from December 2014 to March 2017.

RESULTS

A total of 707 patients diagnosed with STEMI were evaluated, of which 589 were attended at SUS and 118 at the private network. The use of DES in PA was lower in SUS compared to the private network in both the total sample (10.5% vs 82.4%, p<0.001) and in subgroup diabetic patients (8.7% vs 90.6%, p < 0.001), respectively. In all hypotheses tested, the level of significance was 5% (p < 0.05).

CONCLUSIONS

The study reveals a disparity in the use of DES during the performance of PA between the public and private network, both in the total sample and the subgroup for diabetics, with lower rates for SUS users, demonstrating the challenges that need to be overcome in order to achieve quality improvements of the services provided.