Stent thrombosis late after implantation of first-generation drug-eluting stents: a cause for concern

Drug-coated balloons for coronary artery disease: An updated review with future perspectives

Since the advent of coronary stents, two of the most common long-term complications after percutaneous coronary intervention (PCI) are in-stent restenosis (ISR) and stent thrombosis (ST). Although the rates of ST have been nearly abolished and ISR rates have declined with the current gold-standard second-generation drug-eluting stents (DES), late ISR of DES remains a valid concern in the field of interventional cardiology. The drug-coated balloon (DCB) is a non-stent technology that relies on the concept of targeted homogeneous drug delivery from an inflated balloon to restore luminal vascularity, treat atherosclerosis, and overcome some limitations of PCI, including ISR and prolonged dual antiplatelet therapy to prevent ST by leaving nothing behind. Most clinical evidence on coronary DCBs predominantly comes from small, randomized data and registries using paclitaxel DCBs for ISR and de novo lesions in the coronary space. Since 2014, outside the United States, DCBs have been approved for the treatment of ISR, with a class I recommendation by the European Society of Cardiology. The Food and Drug Administration very recently approved the Agent DCB to treat ISR in patients with coronary artery disease in the US. Additionally, recent randomized clinical data also showed DCB's safety and efficacy for the treatment of de novo small-vessel disease and high-bleeding-risk patients, while their role for other clinical situations including acute coronary syndrome, large-vessel disease, bifurcation lesions, and long-diffuse distal lesions is currently under investigation. Herein, we review the evidence-based role of DCBs in the treatment of coronary lesions and offer future perspectives.

Coronary stent failure: role of a blended approach with drug-coated balloons for complex lesions

The management of coronary artery disease by means of percutaneous approach have been focused initially to overcome the recoil and acute occlusion after vessel ballooning; therefore, to develop and improve metallic stent platforms, and later drug-eluting technologies. Contemporarily, the necessity emerged to optimize interventional procedures using functional physiologic tests and intravascular imaging guidance, but still stent failures, especially in the complex lesion setting, continue to be not negligible. This comprehensive review is focused on the technology of drug-coated balloons as a tool to treat coronary artery disease without the need for metal implantation but still eluting antirestenotic drugs such as paclitaxel or sirolimus. We delve into these technologies, the drugs, the technical aspects of the deployment and the most updated evidence also proposing a dedicated interventional algorithm. There is solid data to support the use of drug-coated balloons in patients with in-stent restenosis and de-novo small coronary artery disease but also new evidence with promising results from recent studies indicate the feasibility of this approach in complex coronary interventions, bifurcation lesions and larger coronary vessels. In this state-of-the-art review, we also propose a blended approach based on the combination of drug-eluting stents and drug-coated balloons, keeping in mind the necessity to reduce the total stent length in order to reduce the long-term risk of complications.

Revolutionizing Cardiovascular Frontiers: A Dive Into Cutting-Edge Innovations in Coronary Stent Technology

Plain balloon angioplasty was the initial method used to enlarge the intracoronary lumen size. However, it was linked to acute coronary closure due to early vessel recoil. This led to the invention of coronary stents, which offer mechanical support to open and maintain the vascular lumen. Nevertheless, the metallic scaffold introduced other issues, such as thrombosis and restenosis caused by neointimal proliferation. To address these concerns, polymers were employed to cover the scaffold, acting as drug reservoirs and regulators for controlled drug release. The use of polymers prevents direct contact between blood and metallic scaffolds. Drugs within the stent were incorporated to inhibit proliferation and expedite endothelialization in the healing process. Despite these advancements, adverse effects still arise due to the inflammatory reaction caused by the polymer material. Consequently, resorbable polymers and scaffolds were later discovered, but they have limitations and are not universally applicable. Various scaffold designs, thicknesses, materials, polymer components, and drugs have their own advantages and complications. Each stent generation has been designed to address the shortcomings of the preceding generation, yet new challenges continue to emerge. Conflicting data regarding the long-term safety and efficacy of coronary stents, especially in the extended follow-up, further complicates the assessment.

Non-invasive recanalization of first-generation sirolimus-eluting stent thrombosis due to stent fracture and coronary artery aneurysm after clopidogrel treatment 15 years after implantation

In 2020, a 48-year-old male patient was admitted to our hospital due to unstable angina. In 2005, three first-generation sirolimus-eluting stents (1st-SESs) had been deployed to his right coronary artery (RCA). Over the past 10 years or so, the patient has been treated with single antiplatelet therapy using aspirin. Coronary angiography (CAG) revealed severe stenosis in the left circumflex artery (LCx) and total occlusion at the proximal portion of the stented RCA. Furthermore, fluoroscopy showed multiple 1st-SES fractures. After ad hoc percutaneous coronary intervention of the LCx, dual antiplatelet therapy (DAPT) was resumed by adding the P2Y12 inhibitor clopidogrel to aspirin. Two months later, CAG revealed complete recanalization and multiple peri-stent coronary artery aneurysms (CAAs) in the RCA. Intravascular ultrasound revealed late-acquired stent malapposition (LSM) and formation of true aneurysms. Coronary angioscopy showed the uncovered struts of the 1st-SES and mural red thrombus. DAPT was continued thereafter, and 8 months later, follow-up CAG showed no significant RCA restenosis. To date, the patient remains free from cardiovascular events. This report documents a rare case of thrombotic occlusion of a 1st-SES with LSM, CAA, and stent fractures followed by non-invasive recanalization after clopidogrel treatment 15 years after 1st-SES implantation.

Learning objective

Stent thrombosis due to stent fracture and coronary aneurysm can occur even years after first-generation sirolimus-eluting stent (1st-SES) implantation. Risk assessment using coronary imaging should be made and long-term dual antiplatelet therapy (DAPT) should be recommended in patients with a high risk of stent thrombosis after 1st-SES implantation. In cases of stent thrombosis of the 1st-SES, resuming DAPT, including P2Y12 receptor inhibitors, may be a useful non-invasive treatment option.

Endovascular Drug Delivery

Drug-eluting stents (DES) and balloons revolutionize atherosclerosis treatment by targeting hyperplastic tissue responses through effective local drug delivery strategies. This review examines approved and emerging endovascular devices, discussing drug release mechanisms and their impacts on arterial drug distribution. It emphasizes the crucial role of drug delivery in modern cardiovascular care and highlights how device technologies influence vascular behavior based on lesion morphology. The future holds promise for lesion-specific treatments, particularly in the superficial femoral artery, with recent CE-marked devices showing encouraging results. Exciting strategies and new patents focus on local drug delivery to prevent restenosis, shaping the future of interventional outcomes. In summary, as we navigate the ever-evolving landscape of cardiovascular intervention, it becomes increasingly evident that the future lies in tailoring treatments to the specific characteristics of each lesion. By leveraging cutting-edge technologies and harnessing the potential of localized drug delivery, we stand poised to usher in a new era of precision medicine in vascular intervention.

Comparison of Clinical Outcomes Among Various Percutaneous Coronary Intervention Strategies for Small Coronary Artery Disease

It remains unclear which percutaneous coronary intervention (PCI) strategy is the most preferable in patients with small-vessel coronary artery disease (CAD). We sought to evaluate the clinical efficacy of various PCI strategies for patients with small-vessel CAD through a network meta-analysis of randomized controlled trials (RCTs). We searched multiple databases for RCTs investigating the efficacy of the following PCI strategies for small-vessel CAD (<3 mm in diameter): drug-coated balloons (DCB), early-generation paclitaxel-eluting stents and sirolimus-eluting stents (SES), newer-generation drug-eluting stents (DES), bare-metal stents (BMS), cutting balloon angioplasty, and balloon angioplasty (BA). The primary outcome was the trial-defined major adverse cardiovascular events (MACE), mostly defined as a composite of death, myocardial infarction, and revascularization. The secondary outcomes included each component of MACE and angiographic binary restenosis. We performed a sensitivity analysis for RCTs without BMS or first-generation DES. Our search identified 29 eligible RCTs, including 8,074 patients among the 8 PCI strategies. SES significantly reduced MACE compared with BA (hazard ratio 0.23, 95% confidence interval 0.10 to 0.54) with significant heterogeneity (I2 = 55.9%), and the rankogram analysis showed that SES was the best. There were no significant differences between DCB and newer-generation DES in any clinical outcomes, which was consistent in the sensitivity analysis. BMS and BA were ranked as the worst 2 for most clinical outcomes. In conclusion, SES was ranked as the best for reducing MACE. There were no significant differences in clinical outcomes between DCB and newer-generation DES. BMS and BA were regarded as the worst strategies for small-vessel CAD.

Sex-based differences in ischemic cardiovascular and bleeding outcomes following implantation of drug-eluting stent in patients at high bleeding risk

BACKGROUND

Patients with high bleeding risk (HBR) may exhibit uncertain adherence to dual antiplatelet therapy (DAPT) following drug-eluting stent (DES) implantation. The current population-based cohort study aimed to investigate the sex-based differences in adverse outcomes among the HBR population by analyzing the National Health Insurance Research Database in Taiwan.

METHODS

Patients who had HBR features defined by the Academic Research Consortium (ARC) and received DES implantation between January 1, 2007, and December 31, 2017, were enrolled. Propensity score matching was adopted to select 3,981 pairs with similar clinical cardiovascular risks but different sexes. A competing risk model was performed to evaluate the risk of adverse ischemic events (cardiac death, nonfatal myocardial infarction, and ischemic stroke) and any bleeding events in both sexes. Noncardiac death was considered a competing risk.

RESULTS

Within a 5-year follow-up, the incidence rates (per 1,000 person-year (95% confidence interval (CI)) of composite ischemic events and any bleeding events in males were respectively 44.09 (40.25-48.30) and 42.55 (38.79-46.68), while those in females were respectively 40.18 (36.51-44.23) and 42.35 (38.57-46.51). After adjustment for clinical variables, male patients had a marginally increased risk in the composite ischemic events (adjusted subdistribution hazard ratio (SHR) = 1.15 (1.00-1.31), p = 0.045) and a similar risk of any bleeding events (adjusted SHR = 1.00 (0.88-1.15), p = 0.946) compared with female patients.

CONCLUSIONS

Of the HBR population, males had an increased risk of ischemic outcomes but a similar risk of bleeding compared with females following DES implantation.

Shortened Duration of Dual Antiplatelet Therapy Following Percutaneous Coronary Intervention: A Contemporary Clinical Review

Percutaneous coronary intervention with stent implantation is an integral aspect of minimally interventional cardiac procedures. The technology and techniques behind stent design and implantation have evolved rapidly over several decades. However, continued discourse remains around optimal peri- and post-interventional management with dual antiplatelet therapy to minimise both major cardiovascular or cerebrovascular events and iatrogenic bleeding risk. Standard guidelines around dual antiplatelet therapy historically recommended long-term dual antiplatelet therapy for 12 months (with consideration for >12 months in certain patients); however, emerging data and generational improvements in the safety of drug-eluting stents have ushered in a new era of short-term therapy to reduce the incidence of major bleeding events. This case review will provide an overview of the current state of guidelines around duration of dual antiplatelet therapy and examine recent updates and continued gaps in existing research.

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

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

Personalized Approaches to Antiplatelet Treatment for Cardiovascular Diseases: An Umbrella Review

Antiplatelet therapy is the cornerstone of antithrombotic prevention in patients with established atherosclerosis, since it has been proven to reduce coronary, cerebrovascular, and peripheral thrombotic events. However, the protective effect of antiplatelet agents is counterbalanced by an increase of bleeding events that impacts on patients' mortality and morbidity. Over the last years, great efforts have been made toward personalized antithrombotic strategies according to the individual bleeding and ischemic risk profile, aiming to maximizing the net clinical benefit. The development of risk scores, consensus definitions, and the new promising artificial intelligence tools, as well as the assessment of platelet responsiveness using platelet function and genetic testing, are now part of an integrated approach to tailored antithrombotic management. Moreover, novel strategies are available including dual antiplatelet therapy intensity and length modulation in patients undergoing myocardial revascularization, the use of P2Y12 inhibitor monotherapy for long-term secondary prevention, the implementation of parenteral antiplatelet agents in high-ischemic risk clinical settings, and combination of antiplatelet agents with low-dose factor Xa inhibitors (dual pathway inhibition) in patients suffering from polyvascular disease. This review summarizes the currently available evidence and provides an overview of the principal risk-stratification tools and antiplatelet strategies to inform treatment decisions in patients with cardiovascular disease.

Phase-transited lysozyme nanofilm with co-immobilized copper ion and heparin as cardiovascular stent multifunctional coating

Cardiovascular metal stents have shown potential in the treatment of coronary artery disease using percutaneous coronary intervention. However, thrombosis, endothelialization, and new atherosclerosis after stent implantation remain unsolved problems. Herein, a multifunctional coating material based on phase-transited lysozyme was developed to promote stent endothelialization and simultaneously reduce thrombus events by embedding moieties of heparin and co-immobilized copper ions for in-situ catalyzing nitric oxide (NO) generation. The lysozyme-based biomimetic coating is compatible with blood and enables facile loading and sustainable release of copper ions to produce NO with donors via catalytic reaction. The novel coating strategy displayed several bio-effects of anti-thrombosis; it synergistically promoted endothelial cell growth and inhibited smooth muscle cell growth. Thus, this systemic in vitro study will provide a foundation for developing multifunctional cardiovascular stents in clinical settings.

Liquid Metal-Based Flexible Bioelectrodes for Management of In-Stent-Restenosis: Potential Application

Although vascular stents have been widely used in clinical practice, there is still a risk of in-stent restenosis after their implantation. Combining conventional vascular stents with liquid metal-based electrodes with impedance detection, irreversible electroporation, and blood pressure detection provides a new direction to completely solve the restenosis problem. Compared with conventional rigid electrodes, liquid metal-based electrodes combine high conductivity and stretchability, and are more compliant with the implantation process of vascular stents and remain in the vasculature for a long period of time. This perspective reviews the types and development of conventional vascular stents and proposes a novel stent that integrates liquid metal-based electrodes on conventional vascular stents. This vascular stent has three major functions of prediction, detection and treatment, and is expected to be a new generation of cardiovascular implant with intelligent sensing and real-time monitoring.

Novel usage of everolimus-eluting coronary stent for intracranial atherosclerotic disease: a technical report and case series

Objectives

This report describes the use of an Everolimus-eluting stent (Xience Skypoint stent) for the treatment of medically-refractory ICAD.

Design

Retrospective, case-series.

Setting

In-hospital patients.

Participants

All patients in this report had a history of stroke secondary to ICAD. All patients failed aggressive medical treatments and had recurrence of symptoms despite anticoagulation or dual-antiplatelet therapy plus a statin. Diagnostic angiogram in each case showed severe vessel stenosis, therefore patients were recommended for intracranial artery stenting.

Main outcome measures

Technical feasibility of deploying Xience Skypoint stent for treatmet of ICAD.

Results

The Xience Skypoint stent was safely and effectively deployed in the vertebral artery (x1) and the internal carotid artery (x2) using trans-ulnar (x1), trans-radial (x1), and trans-femoral (x1) approaches without the use of an intermediate catheter.

Conclusion

Second-generation EES such as Xience Skypoint may be utilized for treatment of medically-refractory ICAD. This technical report serves as a proof of concept for further studies analysing long-term safety and efficacy of such stents for treatment of ICAD.

Long-term Outcomes for Drug-eluting Balloons versus Drug-eluting Stents in the Treatment of Small Vessel Coronary Artery Disease: A Systematic Review and Meta-analysis

Background: This systematic review and meta-analysis compares long-term outcomes follow-up data comparing drug-eluting balloons (DEBs) and drug-eluting stents (DESs) in interventional treatment of small coronary artery disease (<3 mm). Methods: A systematic review was undertaken along with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The primary outcome was 1-3-year performance of DEB versus DES in major adverse cardiac events. Secondary outcomes include all-cause mortality, MI, cardiac death, vessel thrombosis, major bleeding, target vessel revascularisation and target lesion revascularisation. Two independent reviewers extracted data. All outcomes used the Mantel-Haenszel and random effects models. ORs are presented with a 95% CI. Results: Of 4,661 articles, four randomised control trials were included (1,414 patients). DEBs demonstrated reduced rates of non-fatal MI at 1 year (OR 0.44; 95% CI [0.2-0.94]), and BASKET-SMALL 2 reported a significant reduction in 2-year bleeding rates (OR 0.3; 95% CI [0.1-0.91]). There was no significant difference in all other outcomes. Conclusion: Long-term follow-up of DEB and DES use in small coronary arteries demonstrates DEBs be comparable with DESs in all outcomes at 1, 2 and 3 years of follow-up. A significant reduction was found in rates of non-fatal MI at 1 year in the DEB arm, and a reduction in major bleeding episodes at 2 years in the BASKET-SMALL 2 trial. These data highlight the potential long-term utility of novel DEBs in small coronary artery disease revascularisation.

High Non-Cardiac Death Incidence Should Be a Limitation of Drug-Eluting Stents Implantation? Insights from Recent Randomized Data

Despite the introduction of drug-eluting stents (DES) significantly improved the efficacy and safety of percutaneous coronary interventions (PCI), particularly in a high-risk group of patients, the gap between PCI with his competitor’s coronary artery bypass surgery (CABG) and/or optimal medical treatment alone was not reduced. In this revision, we highlighted the fact that in recent years landmark randomized studies reported at mid and long-term follow-ups a high incidence of non-cardiac death, cancer incidence, or both in the DES group of patients. The overall incidence of non-cardiac death was significantly higher in the DES vs. the comparator arm: 5.5% and 3.8%, respectively, p = 0.000018, and non-cardiac death appears to be more divergent between DES vs. the comparator at the extended follow-up to expenses of the last one. One of these trials reported five times greater cancer incidence in the DES arm at late follow-up, 5% vs. 0.7% p < 0.0018. We review the potential reason for these unexpected findings, although we can discard that DES biology could be involved in it. Until all these issues are resolved, we propose that DES implantation should be tailored accorded patient age, life expectancy, and lesion complexity.

Stent Thrombosis and Restenosis with Contemporary Drug-Eluting Stents: Predictors and Current Evidence

Iterations in stent technologies, advances in pharmacotherapy, and awareness of the implications of implantation techniques have markedly reduced the risk of stent failure, both in the form of stent thrombosis (ST) and in-stent restenosis (ISR). However, given the number of percutaneous coronary interventions (PCI) performed worldwide every year, ST and ISR, albeit occurring at a fairly low rate, represent a public health problem even with contemporary DES platforms. The understanding of mechanisms and risk factors for these two PCI complications has been of fundamental importance for the parallel evolution of stent technologies. Risk factors associated with ST and ISR are usually divided into patient-, lesion-, device- and procedure-related. A number of studies have shown how certain risk factors are related to early (1 month) versus late/very late ST (between 1 month and 1 year and >1 year, respectively). However, more research is required to conclusively show the role of time-dependence of risk factors also in the incidence of ISR (early [1 year] or late [>1 year]). A thorough risk assessment is required due to the complex etiology of ST and ISR. The most effective strategy to treat ST and ISR is still to prevent them; hence, it is crucial to identify patient-, lesion-, device- and procedure-related predictors.

P2Y12 Inhibitor Monotherapy versus Conventional Dual Antiplatelet Therapy in Patients with Acute Coronary Syndrome after Percutaneous Coronary Intervention: A Meta-Analysis

P2Y12 inhibitor monotherapy is a feasible alternative treatment for patients after percutaneous coronary intervention (PCI) in the modern era. Clinical trials have shown that it could lower the risk of bleeding complications without increased ischemic events as compared to standard dual antiplatelet therapy (DAPT). However, the efficacy and safety of this novel approach among patients with acute coronary syndrome (ACS) are controversial because they have a much higher risk for recurrent ischemic events. The purpose of this study is to evaluate the efficacy and safety of this novel approach among patients with ACS. We conducted a meta-analysis of randomized controlled trials that compared P2Y12 inhibitor monotherapy with 12-month DAPT in ACS patients who underwent PCI with stent implantation. PubMed, Embase, the Cochrane library database, ClinicalTrials.gov, and other three websites were searched for data from the earliest report to July 2022. The primary efficacy outcome was major adverse cardiovascular and cerebrovascular events (MACCE), a composite of all-cause mortality, myocardial infarction, stent thrombosis, or stroke. The primary safety outcome was major or minor bleeding events. The secondary endpoint was net adverse clinical events (NACE), defined as a composite of major bleeding and adverse cardiac and cerebrovascular events. Five randomized controlled trials with a total of 21,034 patients were included in our meta-analysis. The quantitative analysis showed a significant reduction in major or minor bleeding events in patients treated with P2Y12 inhibitor monotherapy as compared with standard DAPT(OR: 0.59, 95% CI: 0.46-0.75, p < 0.0001) without increasing the risk of MACCE (OR: 0.98, 95% CI: 0.86-1.13, p = 0.82). The NACE was favorable in the patients treated with P2Y12 inhibitor monotherapy (OR: 0.82, 95% CI: 0.73-0.93, p = 0.002). Of note, the overall clinical benefit of P2Y12 inhibitor monotherapy was quite different between ticagrelor and clopidogrel. The incidence of NACE was significantly lower in ticagrelor monotherapy as compared with DAPT (OR: 0.79, 95% CI: 0.68-0.91), but not in clopidogrel monotherapy (OR: 1.14, 95% CI: 0.79-1.63). Both clopidogrel and ticagrelor monotherapy showed a similar reduction in bleeding complications (OR: 0.46, 95% CI: 0.22-0.94; OR: 0.60, 95% CI: 0.44-0.83, respectively). Although statistically insignificant, the incidence of MACCE was numerically higher in clopidogrel monotherapy as compared with standard DAPT (OR: 1.50, 95% CI: 0.99-2.28, p = 0.06). Based on these findings, P2Y12 inhibitor monotherapy with ticagrelor would be a better choice of medical treatment for ACS patients after PCI with stent implantation in the current era.

Evaluation of coronary stents: A review of types, materials, processing techniques, design, and problems

In the world, one of the leading causes of death is coronary artery disease (CAD). There are several ways to treat this disease, and stenting is currently the most appropriate way in many cases. Nowadays, the use of stents has rapidly increased, and they have been introduced in various models, with different geometries and materials. To select the most appropriate stent required, it is necessary to have an analysis of the mechanical behavior of various types of stents. The purpose of this article is to provide a complete overview of advanced research in the field of stents and to discuss and conclude important studies on different topics in the field of stents. In this review, we introduce the types of coronary stents, materials, stent processing technique, stent design, classification of stents based on the mechanism of expansion, and problems and complications of stents. In this article, by reviewing the biomechanical studies conducted in this field and collecting and classifying their results, a useful set of information has been presented to continue research in the direction of designing and manufacturing more efficient stents, although the clinical-engineering field still needs to continue research to optimize the design and construction. The optimum design of stents in the future is possible by simulation and using numerical methods and adequate knowledge of stent and artery biomechanics.

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.

Temporal patterns, characteristics, and predictors of clinical outcomes in patients undergoing percutaneous coronary intervention for stent thrombosis

BACKGROUND

There are limited data on the outcomes of percutaneous coronary intervention (PCI) following stent thrombosis (ST) and differences exist based on timing.

AIMS

Our aim was to study the rates of PCI procedures for an ST indication among all patients admitted for PCI at a national level and to compare their characteristics and procedural outcomes based on ST timing.

METHODS

All PCI procedures in England and Wales (2014-2020) were retrospectively analysed and stratified by the presence of ST into four groups: non-ST, early ST (0-30 days), late ST (>30-360 days), very late ST (>360 days). Multivariable logistic regression models were performed to assess the odds ratios (OR) of in-hospital MACCE (major adverse cardiovascular and cerebrovascular events, a composite of mortality, acute stroke and reinfarction) and mortality.

RESULTS

Overall, 7,923 (1.4%) procedures were for ST indication, most commonly for early ST (n=4,171; 52.6%), followed by very late ST (n=2,801; 35.4%) and late ST (n=951; 12.0%). The rate of PCI for ST declined between 2014 and 2020 (1.7 to 1.4%; p<0.001). Early ST was the only subgroup associated with increased odds of MACCE (OR 1.22, 95% CI: 1.05-1.41), all-cause mortality (OR 1.21, 95% CI: 1.07-1.36) and reinfarction (OR 2.48, 95% CI: 1.48-4.14), compared with non-ST indication. The odds of mortality were significantly reduced in ST patients with the use of intravascular imaging (OR 0.66, 95% CI: 0.48-0.92) and newer P2Y12 inhibitors (ticagrelor: OR 0.69, 95% CI: 0.49-0.95; prasugrel: OR 0.54, 95% CI: 0.30-0.96).

CONCLUSIONS

PCI for ST has declined in frequency over a 7-year period, with most procedures performed for early ST. Among the different times of ST onset, only early ST is associated with worse clinical outcomes after PCI. Routine use of intravascular imaging and newer P2Y12 inhibitors could further improve outcomes in this high-risk procedural group.

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.

Polymer–Metal Composite Healthcare Materials: From Nano to Device Scale

Metals have been investigated as biomaterials for a wide range of medical applications. At nanoscale, some metals, such as gold nanoparticles, exhibit plasmonics, which have motivated researchers’ focus on biosensor development. At the device level, some metals, such as titanium, exhibit good physical properties, which could allow them to act as biomedical implants for physical support. Despite these attractive features, the non-specific delivery of metallic nanoparticles and poor tissue–device compatibility have greatly limited their performance. This review aims to illustrate the interplay between polymers and metals, and to highlight the pivotal role of polymer–metal composite/nanocomposite healthcare materials in different biomedical applications. Here, we revisit the recent plasmonic engineered platforms for biomolecules detection in cell-free samples and highlight updated nanocomposite design for (1) intracellular RNA detection, (2) photothermal therapy, and (3) nanomedicine for neurodegenerative diseases, as selected significant live cell–interactive biomedical applications. At the device scale, the rational design of polymer–metallic medical devices is of importance for dental and cardiovascular implantation to overcome the poor physical load transfer between tissues and devices, as well as implant compatibility under a dynamic fluidic environment, respectively. Finally, we conclude the treatment of these innovative polymer–metal biomedical composite designs and provide a future perspective on the aforementioned research areas.

Frequency, Risk Factors, and Outcome of Definite Stent Thrombosis: A Single-Center Experience

Introduction

Stent thrombosis (ST) is a serious and potentially life-threatening complication of primary or complex high-risk percutaneous coronary intervention (PCI). Multiple factors are said to precipitate ST, related to the patient's clinical comorbidities, lesion characteristics, operative technique, and post-procedural care. The older-generation stents were thought to be involved in early ST. Though the new generation of drug-eluting stents decreases the incidence of early and late ST, patients are still at risk of very late stent thrombosis (VLST).

Objective

To evaluate the frequency, risk factors, and outcomes of definite ST in developing and resource-constrained countries like Pakistan, where PCIs, including primary PCI, complex PCI, and PCI in high-risk populations, are performed routinely.

Methods

This observational cross-sectional study included all patients who underwent primary and complex high PCI between 2012 and 2017 at TABBA Heart Institute (THI), Karachi, Pakistan.

Results

We included a total of 6587 patients in our study, and among the enrolled sample size, 22 (0.33%) had definite ST. Acute stent thrombosis (AST) was found in seven patients, sub-acute stent thrombosis (SAST) in 10, late stent thrombosis (LST) in two, and VLST were observed in three patients. The basic characteristics of our study ST population were as follows: mean age was 58 years, 95.5% were male, 4.5% were female, nine patients (40%) had diabetes mellitus, 15 patients (68%) had hypertension, 11 (50%) had dyslipidemia, and four patients were smokers (18%).

Conclusion

The frequency, risk factors, and rate of mortality of definite ST in the Pakistani population who underwent primary and complex high-risk PCI reflect nearly equal statistics observed in other studies. As seen in other international studies, the incidence rate of VLST was higher in our population.

Evolution of drug-eluting coronary stents: a back-and-forth journey from the bench-to-bedside

Coronary stents have revolutionized the treatment of coronary artery disease. Compared with balloon angioplasty, bare-metal stents effectively prevented abrupt vessel closure but were limited by in-stent restenosis due to smooth muscle cell proliferation and neointimal hyperplasia. The first-generation drug-eluting stent (DES), with its antiproliferative drug coating, offered substantial advantages over bare-metal stents as it mitigated the risk of in-stent restenosis. Nonetheless, they had several design limitations that increased the risk of late stent thrombosis. Significant advances in stent design, including thinner struts, enhanced polymers' formulation, and more potent antiproliferative agents, have led to the introduction of new-generation DES with a superior safety profile. Cardiologists have over 20 different DES types to choose from, each with its unique features and characteristics. This review highlights the evolution of stent design and summarizes the clinical data on the different stent types. We conclude by discussing the clinical implications of stent design in high-risk subsets of patients.

Current Status and Outlook of Temporary Implants (Magnesium/Zinc) in Cardiovascular Applications

Medical application materials must meet multiple requirements, and the designed material must mimic the structure, shape. and support the formation of the replacing tissue. Magnesium (Mg) and Zinc alloys (Zn), as a “smart” biodegradable material and as “the green engineering material in the 21st century”, have become an outstanding implant material due to their natural degradability, smart biocompatibility, and desirable mechanical properties. Magnesium and Zinc are recognized as the next generation of cardiovascular stents and bioresorbable scaffolds. At the same time, improving the properties and corrosion resistance of these alloys is an urgent challenge. particularly to promote the application of magnesium alloys. A relatively fast deterioration rate of magnesium-based materials generally results in premature mechanical integrity compromise and local hydrogen build-up, resulting in restricted applicability. This review article aims to give a comprehensive comparison between Zn-based alloys and Mg-based alloys, focusing primarily on degradation and biocompatibility for cardiovascular applications. The recent clinical trials using these biodegradable metals have also been addressed.

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.

Risk of Heart Failure in Patients with ST-Elevation Myocardial Infarction Receiving Drug-Eluting Stent Implantation and Undefined Duration of Antiplatelets

It remains unknown as to whether the use of new-generation drug-eluting stent (NG-DES) in patients with ST-elevation myocardial infarction (STEMI) who receive an undefined duration of dual antiplatelet therapy (DAPT) reduces the risk of hospitalization for heart failure (HHF). In this population-based retrospective cohort study, we applied propensity score matching to select 6831 pairs of patients with STEMI who had similar baseline characteristics and received either NG-DES or bare-metal stent (BMS) implantation between 1 January 2007 and 31 December 2016. The risk of stent-associated HHF was evaluated, wherein death was considered a competing risk. Rates of cumulative incidence competing risk for HHF at the 1, 2, 3, 4, and 5 year follow-up were lower in the NG-DES group (3.79%, 5.21%, 6.15%, 7.01%, and 8.29%, respectively) than in the BMS group (4.51%, 6.21%, 7.32%, 8.33%, and 9.83%, respectively). NG-DES implantation was associated with a lower risk of HHF than BMS implantation after 5 years, with an adjusted subdistribution hazard ratio of 0.82 (95% confidence interval 0.72−0.92, p = 0.001). These results accord with those of patients who received DAPT for >6 months. Our findings highlight that NG-DESs may reduce HHF risk in patients with STEMI receiving an undefined duration of DAPT.

Antithrombotic Therapy After Acute Coronary Syndromes or Percutaneous Coronary Interventions in East Asian Populations

Because guidelines and recommendations in response to multiple randomized clinical trials (RCTs) of new therapies undergo rapid changes, antithrombotic therapies for patients after acute coronary syndrome, or percutaneous coronary intervention, are becoming more complex in daily clinical practice. The proportion of Asian populations enrolled in landmark RCTs is substantially low, which limits the direct application of trial findings into clinical practice in Asian countries. Moreover, compared with Caucasian patients, East Asian patients are considered to have a different ischemia/bleeding propensity in response to antithrombotic therapy, known as the "East Asian paradox" (ie, more bleeding events but fewer thromboembolic events). Coincident with consecutive RCTs in Western populations to optimize antithrombotic strategies, several such studies have now been conducted in East Asian cohorts. Herein, we provide a comprehensive summary of the key RCTs in this regard and propose future directions and perspectives for optimal antithrombotic therapies in East Asian patients.

Arsenic trioxide activates yes-associated protein by lysophosphatidic acid metabolism to selectively induce apoptosis of vascular smooth muscle cells

Inhibition of vascular smooth muscle cells (VSMCs) proliferation without dysregulating endothelial cells (ECs) may provide an ideal therapy for in-stent restenosis. Due to its anti-proliferation effect on VSMCs and pro-endothelium effect, arsenic trioxide (ATO) has been used in a drug-eluting stent in a recent clinical trial. However, the underlying mechanism by which ATO achieves this effect has not been determined. In the present work, we showed that ATO induced apoptosis in VSMCs but not in ECs. Mechanistically, ATO achieved this through modulation of cellular metabolism to increase lysophosphatidic acid (LPA) in VSMCs, while LPA concentration was stable in ECs. The elevated LPA facilitated the nuclear accumulation and initiated the transcriptional function of Yes-associated protein (YAP) in VSMCs. YAP regulated the transcription of N6-Methyladenosine (m⁶A) modulators (Mettl14 and Wtap) to increase the m⁶A methylation levels of apoptosis-related genes to induce their high expression and exacerbate VSMCs apoptosis. On the other hand, YAP nuclear accumulation in ECs was not observed. Collectively, our data exhibited the molecular process involved in selective apoptosis of VSMCs induced by ATO.

Surface engineering and the application of laser-based processes to stents - A review of the latest development

Late in-stent thrombus and restenosis still represent two major challenges in stents’ design. Surface treatment of stent is attracting attention due to the increasing importance of stenting intervention for coronary artery diseases. Several surface engineering techniques have been utilised to improve the biological response in vivo on a wide range of biomedical devices. As a tailorable, precise, and ultra-fast process, laser surface engineering offers the potential to treat stent materials and fabricate various 3D textures, including grooves, pillars, nanowires, porous and freeform structures, while also modifying surface chemistry through nitridation, oxidation and coatings. Laser-based processes can reduce the biodegradable materials' degradation rate, offering many advantages to improve stents’ performance, such as increased endothelialisation rate, prohibition of SMC proliferation, reduced platelet adhesion and controlled corrosion and degradation. Nowadays, adequate research has been conducted on laser surface texturing and surface chemistry modification. Laser texturing on commercial stents has been also investigated and a promotion of performance of laser-textured stents has been proved.

In this critical review, the influence of surface texture and surface chemistry on stents performance is firstly reviewed to understand the surface characteristics of stents required to facilitate cellular response. This is followed by the explicit illustration of laser surface engineering of stents and/or related materials. Laser induced periodic surface structure (LIPSS) on stent materials is then explored, and finally the application of laser surface modification techniques on latest generation of stent devices is highlighted to provide future trends and research direction on laser surface engineering of stents.

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Compared conventional surface engineering with laser-based methods for biomedical devices.

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Explained the influence of texture geometry and surface chemistry on stents biological response.

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Reviewed state of the art in laser surface engineering of stents for improved biological response.

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Reviewed state of the art in laser surface engineering to control degradation of bioresorbable stents.

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Highlighted novel laser surface engineering designs for improved stents'performance.

Very Long-term Safety and Effectiveness of Drug-Eluting or Bare-Metal Stents for Left Main Coronary Disease

Background

Limited data are available on the long-term outcomes of drug-eluting stents (DES) vs bare-metal stents (BMS) in patients with left main coronary artery (LMCA) disease.

Methods

In this observational cohort of the Revascularization for Unprotected Left Main Coronary Artery Stenosis: Comparison of Percutaneous Coronary Angioplasty vs Surgical Revascularization (MAIN-COMPARE) registry, we evaluated patients with unprotected LMCA stenosis who received DES or BMS between January 2000 and June 2006. The primary outcome was a composite of all-cause death or myocardial infarction (MI) at 10 years. Adjusted outcomes were compared using propensity scores and inverse probability of treatment weighting.

Results

A total of 1102 patients underwent DES (n = 784) or BMS (n = 318) during the study period. At 10 years, the adjusted rate of the primary outcome was significantly lower in DES group than in the BMS group (27.9% vs 37.0%; hazard ratio [HR], 0.71; 95% confidence interval [CI], 0.53-0.94; P = 0.02). The adjusted 10-year mortality rate was significantly lower in DES group than in the BMS group (20.6% vs 29.6%; HR, 0.65; 95% CI, 0.46-0.91; P = 0.01), whereas the 10-year rate of MI was similar between the 2 groups (9.9% vs 11.0%; HR, 0.93; 95% CI, 0.54-1.59; P = 0.78). DES use was associated with a significant reduction in the rate of target-lesion revascularization (10.2% vs 21.8%; HR, 0.41; 95% CI, 0.27-0.61; P < 0.001).

Conclusions

In this 10-year follow-up study in patients with LMCA disease, DES use was associated with a significant reduction in the rate of the composite of death or MI, mortality, and target-lesion revascularization, when compared with BMS.

XIENCE Implantation Followed By Short Dual Antiplatelet Therapy: 'The New Normal'?

The XIENCE family of everolimus-eluting stents ranks among the most used and most widely studied drug-eluting stents worldwide. In patients at high bleeding risk undergoing non-complex percutaneous coronary intervention with these stents, a shortened dual antiplatelet therapy (DAPT) regimen of 1-3 months appears to be associated with a reduced rate of major bleeding, a similar rate of ischaemic events and a very low incidence of stent thrombosis after DAPT discontinuation compared with DAPT up to 12 months.

[stent thrombosis : A won battle ? (data from the France PCI registry)]

GOAL

The aim of the study is to assess the incidence, risk factors and prognosis of definite stent thrombosis (ST) at 1 year in the France PCI multicenter prospective registry.

PATIENTS AND METHODS

Only patients who underwent coronary angioplasty with at least one stent implantation between 1^st January 2014 and 31 December 2019 were included. The population was separated into 2 groups: the "ST" group with stent thrombosis and the "control" group without stent thrombosis.

RESULTS

35,435 patients were included. 256 patients (0.72%) presented a ST at 1 year. The rate of ST decreased significantly in acute coronary syndrome (1.5% in 2014 vs. 0.73% in 2019; p = 0.05) but not in chronic coronary syndrome (0.46% in 2014 vs 0.40%; p = 0.98). The risk factors are young age (65.8 years vs 68.2; p = 0.002), clinical context (35.27% vs 16.68%; p = 0.0001), diabetes (35.2 % vs 26.4%; p = 0.002), renal failure (11.7% vs 8%; p = 0.009) and history of coronary angioplasty (28.63% vs 21.86%; p = 0.009) and peripheral arterial disease (14.5% vs 10.1%; p = 0.021), LV dysfunction (37% vs 27.5%; p = 0.003), mean length (39.6 mm vs 31, 7mm; p <0.0001) and the mean number of stents per procedure (1.9 vs 1.6; p <0.0001), a TIMI flow ≤1 pre procedure (21.5% vs 12.4%; p <0.0001) and an intrastent restenosis (11% vs 6%; p <0.0001). The 1-year mortality of the ST group was significantly higher than that of the control group (19.14% vs 5.82%; p <0.0001).

CONCLUSION

Since 2014, the incidence of ST at 1 year has been decreasing but remains stuck at a floor level of 0.54% in 2019. The battle for ST seems to have been partly won and its risk factors well identified, but its mortality is still high.

Preclinical Evaluation of a Novel Polymer-free Everolimus-eluting Stent in a Mid-term Porcine Coronary Restenosis Model

BACKGROUND

Titanium dioxide films exhibit good biocompatibility and may be effective as drug-binding matrices for drug-eluting stents. We conducted a mid-term evaluation of a novel polymer-free everolimus-eluting stent using nitrogen-doped titanium dioxide film deposition (TIGEREVOLUTION^®) in comparison with a commercial durable polymer everolimus-eluting stent (XIENCE Alpine^®) in a porcine coronary restenosis model.

METHODS

Twenty-eight coronary arteries from 14 mini-pigs were randomly allocated to TIGEREVOLUTION^® stent and XIENCE Alpine^® stent groups. The stents were implanted in the coronary artery at a 1.1-1.2:1 stent-to-artery ratio. Eleven stented coronary arteries in each group were finally analyzed using coronary angiography, optical coherence tomography, and histopathologic evaluation 6 months after stenting.

RESULTS

Quantitative coronary analysis showed no significant differences in the pre-procedural, post-procedural, and 6-month lumen diameters between the groups. In the volumetric analysis of optical coherence tomography at 6 months, no significant differences were observed in stent volume, lumen volume, and percent area stenosis between the groups. There were no significant differences in injury score, inflammation score, or fibrin score between the groups, although the fibrin score was zero in the TIGEREVOLUTION^® stent group (0 vs. 0.07 ± 0.11, P = 0.180).

CONCLUSION

Preclinical evaluation, including optical coherence tomographic findings 6 months after stenting, demonstrated that the TIGEREVOLUTION^® stent exhibited efficacy and safety comparable with the XIENCE Alpine^® stent, supporting the need for further clinical studies on the TIGEREVOLUTION^® stent.

The biological responses and mechanisms of endothelial cells to magnesium alloy

Due to its good biocompatibility and degradability, magnesium alloy (Mg alloy) has shown great promise in cardiovascular stent applications. Rapid stent re-endothelialization is derived from migrated and adhered endothelial cells (ECs), which is an effective way to reduce late thrombosis and inhibit hyperplasia. However, fundamental questions regarding Mg alloy affecting migration and adhesion of ECs are not fully understood. Here, we evaluated the effects of Mg alloy on the ECs proliferation, adhesion and migration. A global gene expression profiling of ECs co-culturing with Mg alloy was conducted, and the adhesion- and migration-related genes were examined. We found that Mg alloy had no adverse effects on ECs viability but significantly affected ECs migration and adhesion. Co-cultured with Mg alloy extract, ECs showed contractive adhesion morphology and decreased motility, which was supported by the down-regulation of adhesion-related genes (Paxillin and Vinculin) and migration-related genes (RAC 1, Rho A and CDC 42). Accordingly, the re-endothelialization of Mg alloy stent was inhibited in vivo. Our results may provide new inspiration for improving the broad application of Mg alloy stents.

Comparison of Long-Term Outcomes After Percutaneous Coronary Intervention in Patients With Insulin-Treated Versus Non-Insulin Treated Diabetes Mellitus

There are conflicting data on whether patients with insulin-treated diabetes mellitus (ITDM) have poorer outcomes compared with non-insulin treated diabetic (non-ITDM) patients following percutaneous coronary intervention (PCI). We therefore compared clinical outcomes following PCI in ITDM versus non-ITDM patients. We prospectively collected data on 4,579 patients with diabetes underwent PCI between 2005 and 2014 in a large multicenter registry and dichotomized them as having ITDM (n = 1,111) or non-ITDM (n = 3,468). The non-ITDM group was further divided into diet control only (diet-DM; n = 786) and those taking oral hypoglycemic agents (OHG-DM; n = 2,639), and clinical outcomes were compared with ITDM patients. Median follow-up for long-term mortality was 4.2 years (IQR 2.0 to 6.6 years). ITDM patients were more likely to be female, obese, and have severe renal impairment (all p <0.001). Procedural characteristics were similar other than a greater use of drug-eluting stents in ITDM patients. On multivariable analysis, ITDM was an independent predictor of 12-month major adverse cardiovascular and cerebrovascular events (MACCE; OR 1.26, 95% CI 1.02 to1.55, p = 0.03). Dividing the non-ITDM group further by treatment, a progressively higher rate of 12-month MACCE across the 3 groups was observed (13.5% vs 17.9% vs 21.8%; p <0.001). Long-term mortality was similar in the diet-DM and OHG-DM groups, but significantly higher in the ITDM group on Kaplan-Meier analysis (log-rank p <0.001). In conclusion, there is a clear gradient of adverse outcomes with escalation of therapy from diet control to OHGs to insulin.

Evolution of antithrombotic therapy in patients undergoing percutaneous coronary intervention: a 40-year journey

Since its introduction in 1977, percutaneous coronary intervention has become one of the most commonly performed therapeutic procedures worldwide. Such widespread diffusion, however, would have not been possible without a concomitant evolution of the pharmacotherapies associated with this intervention. Antithrombotic agents are fundamental throughout the management of patients undergoing coronary stent implantation, starting from the procedure itself to the long-term prevention of cardiovascular events. The last 40 years of interventional cardiology have seen remarkable improvements in both drug therapies and device technologies, which largely reflected a progressive understanding of the pathophysiological mechanisms of coronary artery disease, as well as procedure- and device-related adverse events. The purpose of this article is to provide an overview of the important milestones in antithrombotic pharmacology that have shaped clinical practice of today while also providing insights into knowledge gaps and future directions.

Molecular Action of Hydroxytyrosol in Attenuation of Intimal Hyperplasia: A Scoping Review

Objective: Hydroxytyrosol (HT), a polyphenol of olive plant is well known for its antioxidant, anti-inflammatory and anti-atherogenic properties. The aim of this systematic search is to highlight the scientific evidence evaluating molecular efficiency of HT in halting the progression of intimal hyperplasia (IH), which is a clinical condition arises from endothelial inflammation.

Methods: A systematic search was performed through PubMed, Web of Science and Scopus, based on pre-set keywords which are Hydroxytyrosol OR 3,4-dihydroxyphenylethanol, AND Intimal hyperplasia OR Neointimal hyperplasia OR Endothelial OR Smooth muscles. Eighteen in vitro and three in vitro and in vivo studies were selected based on a pre-set inclusion and exclusion criteria.

Results: Based on evidence gathered, HT was found to upregulate PI3K/AKT/mTOR pathways and supresses inflammatory factors and mediators such as IL-1β, IL-6, E-selectin, P-selectin, VCAM-1, and ICAM-1 in endothelial vascularization and functioning. Two studies revealed HT disrupted vascular smooth muscle cells (SMC) cell cycle by dephosphorylating ERK1/2 and AKT pathways. Therefore, HT was proven to promote endothelization and inhibit vascular SMCs migration thus hampering IH development. However, none of these studies described the effect of HT collectively in both vascular endothelial cells (EC) and SMCs in IH ex vivo model.

Conclusions: Evidence from this concise review provides an insight on HT regulation of molecular pathways in reendothelization and inhibition of VSMCs migration. Henceforth, we propose effect of HT on IH prevention could be further elucidated through in vivo and ex vivo model.

Vascular Lesion-Specific Drug Delivery Systems: JACC State-of-the-Art Review

Drug delivery is central to modern cardiovascular care, where drug-eluting stents, bioresorbable scaffolds, and drug-coated balloons all aim to restore perfusion while inhibiting exuberant healing. The promise and enthusiasm of these devices has in some cases exceeded demonstration of efficacy and even understanding of driving mechanisms. The authors review the means of drug delivery in each device, outlining how the technologies affect vascular behavior. They focus on how drug retention and response are governed by lesion morphology: lipid displacing drug-specific binding sites, calcium inhibiting diffusion, blocking thrombi or promoting luminal washout, and vascular healing steering hyperplastic developments. In this regard, the authors outline the fundamental impact of vascular structure on drug delivery and review the development of contemporary and future devices for coronary and peripheral intervention. They look toward a future where incorporating information on lesion distribution is central to therapeutic success and envision a transition toward lesion-specific treatment for improved interventional outcomes.

Multimodality Intravascular Imaging of High-Risk Coronary Plaque

The majority of coronary atherothrombotic events presenting as myocardial infarction (MI) occur as a result of plaque rupture or erosion. Understanding the evolution from a stable plaque into a life-threatening, high-risk plaque is required for advancing clinical approaches to predict atherothrombotic events, and better treat coronary atherosclerosis. Unfortunately, none of the coronary imaging approaches used in clinical practice can reliably predict which plaques will cause an MI. Currently used imaging techniques mostly identify morphological features of plaques, but are not capable of detecting essential molecular characteristics known to be important drivers of future risk. To address this challenge, engineers, scientists, and clinicians have been working hand-in-hand to advance a variety of multimodality intravascular imaging techniques, whereby 2 or more complementary modalities are integrated into the same imaging catheter. Some of these have already been tested in early clinical studies, with other next-generation techniques also in development. This review examines these emerging hybrid intracoronary imaging techniques and discusses their strengths, limitations, and potential for clinical translation from both an engineering and clinical perspective.

Meta-analysis of Duration of Continuous Dual Antiplatelet Therapy and Late Stent Thrombosis After Second-Generation Drug Stent Implantation

INTRODUCTION

The aim of the present study was to perform a systematic comparison of the incidence of late and extremely late stent thrombosis (ST) with short-term and long-term dual antiplatelet therapy (DAPT) after a second-generation drug-eluting stent (DES) implantation.

METHODS

Randomized controlled trials using short-term and long-term DAPT and reporting late ST (30 days-1 year) and extremely late ST (longer than 1 year) after a percutaneous coronary intervention (PCI) with DES were searched and compared in the Life Sciences and Biomedical Information Bibliographic Database (MEDLINE), EMBASE, Cochrane Central, and ClinicalTrials.com. ST was used as the primary endpoint of the therapeutic outcome, and the fixed-effects model (I² < 50%) or random-effects model (I² ≥ 50%) was adopted for the combined analysis. The odds ratio (OR) and 95% confidence interval (CIs) were used to represent the results. P < 0.05 in the combined result indicated that the difference was statistically significant.

RESULTS

A total of five randomized controlled trials consisting of 7142 patients were included, with 3556 cases of short-term DAPT (at most 6 months), and 3586 cases of long-term DAPT (at least 12 months). There was no significant difference between late ST and administration duration of DAPT (OR 0.98, 95% CI 0.30-3.18; P = 0.97, I² = 0%). There was also no significant difference between the incidence of extremely late ST and the duration of DAPT application (OR 0.30, 95% CI 0.03-2.95; P = 0.31).

CONCLUSION

The duration of continuous DAPT application had no effect on the occurrence of late and extremely late ST.

Designing Better Cardiovascular Stent Materials - A Learning Curve

Cardiovascular stents are life-saving devices and one of the top 10 medical breakthroughs of the 21st century. Decades of research and clinical trials have taught us about the effects of material (metal or polymer), design (geometry, strut thickness, and the number of connectors), and drug-elution on vasculature mechanics, hemocompatibility, biocompatibility, and patient health. Recently developed novel bioresorbable stents are intended to overcome common issues of chronic inflammation, in-stent restenosis, and stent thrombosis associated with permanent stents, but there is still much to learn. Increased knowledge and advanced methods in material processing have led to new stent formulations aimed at improving the performance of their predecessors but often comes with potential tradeoffs. This review aims to discuss the advantages and disadvantages of stent material interactions with the host within five areas of contrasting characteristics, such as 1) metal or polymer, 2) bioresorbable or permanent, 3) drug elution or no drug elution, 4) bare or surface-modified, and 5) self-expanding or balloon-expanding perspectives, as they relate to pre-clinical and clinical outcomes and concludes with directions for future studies.

Efficacy and Safety of Dual-Drug-Eluting Stents for de Novo Coronary Lesions in South Korea-The Effect Trial

Background: Drug-eluting stents (DESs) are commonly used in percutaneous coronary intervention (PCI) procedures; however, complications including in-stent restenosis and stent thrombosis are significant challenges. The dual-DES is a stent that elutes two drugs to target various stages of the restenosis reaction. This study investigated the safety and efficacy of dual-DES in clinical practice. Methods: This study included 375 patients who underwent PCI with Cilotax^™ or DXR^™ dual-DESs at one of 13 centers in South Korea. The primary endpoint was target lesion failure (TLF) within 1 year. The secondary endpoints were cardiac death, myocardial infarction (MI), target lesion revascularization (TLR), and stent thrombosis. Results: The rates of TLF in dual-DESs (3.7%) were comparable to those reported in conventional DES. In addition, the DXR^™ group had a significantly lower rate of TLF than the Cilotax^™ group. In multivariate analysis, the DXR^™ group had a lower risk of TLF (adjusted hazard ratio (HR) 0.30, 95% CI 0.09–0.92, p = 0.036) and MI (adjusted HR 0.16, 95% CI 0.03–0.82, p = 0.027) than the Cilotax^™ group. Conclusion: Dual-DESs had similar clinical outcomes regarding efficacy and safety as conventional DES. Among the dual-DES, the DXR^™ stent as a new generation dual-DES had more favorable clinical outcomes than the Cilotax^™ stent.

The role of intracoronary imaging in translational research

Atherosclerotic cardiovascular disease is a key public health concern worldwide and leading cause of morbidity, mortality and health economic costs. Understanding atherosclerotic plaque microstructure in relation to molecular mechanisms that underpin its initiation and progression is needed to provide the best chance of combating this disease. Evolving vessel wall-based, endovascular coronary imaging modalities, including intravascular ultrasound (IVUS), optical coherence tomography (OCT) and near-infrared spectroscopy (NIRS), used in isolation or as hybrid modalities, have been advanced to allow comprehensive visualization of the pathological substrate of coronary atherosclerosis and accurately measure temporal changes in both the vessel wall and plaque characteristics. This has helped further our appreciation of the natural history of coronary artery disease (CAD) and the risk for major adverse cardiovascular events (MACE), evaluate the responsiveness to conventional and experimental therapeutic interventions, and assist in guiding percutaneous coronary intervention (PCI). Here we review the use of different imaging modalities for these purposes and the lessons they have provided thus far.