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Polymeric coating is one of the most used surface modification techniques on stents to reduce late stent thrombosis and restenosis. Coating process parameters must need to be rigorously controlled in biomedical applications. Spray coating is one of the most promising process used to recover commercial coronary stents, wherein uniform surfaces must be achieved. A novel low-cost spray coating machine was developed constructed using an airbrush with adjustable pressure (30 psi to 45 psi). Additionally, time and distance control systems were adapted for tubular samples, and a motor controlled their rotation. Polylactic acid (PLA) was deposited on 316L stainless steel tubes, using a spray coating technique for coronary stents purposes in order to achieve optimal film characteristics. Scanning electron microscopy was used to analyze the coating homogeneity. Other physical characteristics such as weight and surface roughness were measured to assess the feasibility of the proposed system. [ABSTRACT FROM AUTHOR]

There was no study evaluating the effects of an aspirin-free strategy in patients undergoing complex percutaneous coronary intervention (PCI). The authors aimed to evaluate the efficacy and safety of an aspirin-free strategy in patients undergoing complex PCI. We conducted the prespecified subgroup analysis based on complex PCI in the STOPDAPT-3 (ShorT and OPtimal duration of Dual AntiPlatelet Therapy after everolimus-eluting cobalt-chromium stent-3), which randomly compared low-dose prasugrel (3.75 mg/d) monotherapy to dual antiplatelet therapy (DAPT) with low-dose prasugrel and aspirin in patients with acute coronary syndrome or high bleeding risk. Complex PCI was defined as any of the following 6 criteria: 3 vessels treated, ≥3 stents implanted, ≥3 lesions treated, bifurcation with 2 stents implanted, total stent length >60 mm, or a target of chronic total occlusion. The coprimary endpoints were major bleeding events (Bleeding Academic Research Consortium 3 or 5) and cardiovascular events (a composite of cardiovascular death, myocardial infarction, definite stent thrombosis, or ischemic stroke) at 1 month. Of the 5,966 study patients, there were 1,230 patients (20.6%) with complex PCI. Regardless of complex PCI, the effects of no aspirin relative to DAPT were not significant for the coprimary bleeding (complex PCI: 5.30% vs 3.70%; HR: 1.44; 95% CI: 0.84-2.47; P = 0.18 and noncomplex PCI: 4.26% vs 4.97%; HR: 0.85; 95% CI: 0.65-1.11; P = 0.24; P for interaction = 0.08) and cardiovascular (complex PCI: 5.78% vs 5.93%; HR: 0.98; 95% CI: 0.62-1.55; P = 0.92 and noncomplex PCI: 3.70% vs 3.10%; HR: 1.20; 95% CI: 0.88-1.63; P = 0.25; P for interaction = 0.48) endpoints without significant interactions. The effects of the aspirin-free strategy relative to standard DAPT for the cardiovascular and major bleeding events were not different regardless of complex PCI. (ShorT and OPtimal duration of Dual AntiPlatelet Therapy after everolimus-eluting cobalt-chromium stent-3 [STOPDAPT-3]; NCT04609111) [Display omitted] [ABSTRACT FROM AUTHOR]

It remains unclear whether clopidogrel is better suited than aspirin as the long-term antiplatelet monotherapy following dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI). This study compared clopidogrel monotherapy following 1 month of DAPT (clopidogrel group) with aspirin monotherapy following 12 months of DAPT (aspirin group) after PCI for 5 years. STOPDAPT-2 (Short and Optimal Duration of Dual Antiplatelet Therapy 2) is a multicenter, open-label, adjudicator-blinded, randomized clinical trial conducted in Japan. Patients who underwent PCI with cobalt-chromium everolimus-eluting stents were randomized in a 1-to-1 fashion either to clopidogrel or aspirin groups. The primary endpoint was a composite of cardiovascular outcomes (cardiovascular death, myocardial infarction, stroke, or definite stent thrombosis) or major bleeding (TIMI major or minor bleeding). Among 3,005 study patients (age: 68.6 ± 10.7 years; women: 22.3%; acute coronary syndrome: 38.3%), 2,934 patients (97.6%) completed the 5-year follow-up (adherence to the study drugs at 395 days: 84.7% and 75.9%). The clopidogrel group compared with the aspirin group was noninferior but not superior for the primary endpoint (11.75% and 13.57%, respectively; HR: 0.85; 95% CI: 0.70-1.05; P noninferiority < 0.001; P superiority = 0.13), whereas it was superior for the cardiovascular outcomes (8.61% and 11.05%, respectively; HR: 0.77; 95% CI: 0.61-0.97; P = 0.03) and not superior for major bleeding (4.44% and 4.92%, respectively; HR: 0.89; 95% CI: 0.64-1.25; P = 0.51). By the 1-year landmark analysis, clopidogrel was numerically, but not significantly, superior to aspirin for cardiovascular events (6.79% and 8.68%, respectively; HR: 0.77; 95% CI: 0.59-1.01; P = 0.06) without difference in major bleeding (3.99% and 3.32%, respectively; HR: 1.23; 95% CI: 0.84-1.81; P = 0.31). Clopidogrel might be an attractive alternative to aspirin with a borderline ischemic benefit beyond 1 year after PCI. [Display omitted] [ABSTRACT FROM AUTHOR]

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The use of chemically modified nanocomposites for atherosclerotic plaques can open up new opportunities for studying their effect on changing the structure of the plaque itself. It was shown on the model of the greater omentum of two groups of experimental animals (rats n = 30), which were implanted with Fe@C NPs nanocomposites of 10–30 Nm size into the omentum area. Group 1 (n = 15) consisted of animals that were implanted with chemically modified Fe@C NPs nanocomposites and control group 2 (n = 15) was with non-modified Fe@C NPs nanocomposites. After 1, 2 and 3 weeks we conducted the morphological study of changes in the structure of the omentum using two dyes (Nile Blue and Sudan III), which are specific for adipose tissue. Chemically modified nanocomposites have demonstrated, in contrast to non-modified nanoparticles, to cause morphological changes in the structure of the greater omentum accompanied by the probable release of a similar antiatherogenic factor. The model of the greater omentum of rats showed that chemically modified nanocomposites cause intravital changes in its structure. Considering that the omentum itself in its qualitative composition is as close as possible to the human atherosclerotic plaque, these morphological changes were described as a "fringing phenomenon", which manifests itself in the omental tissues directly adjacent to the modified nanocomposites. The option of applied use of nanocomposites for the manufacture of a new generation of coronary stents is being considered. [Display omitted] [ABSTRACT FROM AUTHOR]

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Perioperative cell count–associated predictors, including the neutrophil/lymphocyte ratio (N/LR) and platelet/lymphocyte ratio (P/LR), are associated with poor clinical outcomes including myocardial injury. Study investigators aimed to examine the association among the perioperative N/LR, P/LR, and postoperative major adverse cardiovascular and cerebral events (MACCE) after noncardiac surgery in patients with drug-eluting stent (DES) insertion. Retrospective and observational. Single university hospital. The study comprised 965 patients who underwent noncardiac surgery within 6 months after DES implantation. None. Baseline perioperative clinical parameters, including N/LR and P/LR measured before surgery, immediately after surgery, and on postoperative day (POD) 1, were obtained. MACCE was defined as a composite of nonfatal myocardial infarction, coronary revascularization, nonhemorrhagic stroke, and pulmonary embolism within 1 month after surgery. Multivariate logistic regression analysis and propensity score matching were used to identify predictors of MACCE after surgery. MACCE occurred in 67 patients (6.9%) and was more common in patients with N/LR on POD 1 >4.3 (multivariable-adjusted odds ratio [OR] 2.03, 95% confidence interval [CI] 1.12-2.79; p = 0.040 and as a continuous N/LR [OR 1.17, 95% CI 1.08-1.27; p < 0.001]). This association was consistent after propensity score matching and was stronger when the antiplatelet agent was stopped before surgery (OR 3.02, 95% CI 2.14-4.48; p = 0.006 for stopping dual antiplatelet therapy). In patients undergoing noncardiac surgery within 6 months after DES implantation, elevated N/LR on POD 1 is independently associated with postoperative MACCE. Elevated postoperative N/LR as a marker of systemic inflammation may help to predict the development of MACCE in these high-risk patients. [ABSTRACT FROM AUTHOR]

This work focuses on fluid–structure interaction (FSI) between a curved (tortuous) coronary artery with an implanted stent, pulsatile blood flow, and heart contractions. The goal is to understand which geometric distribution of stent struts, given by four different, commercially available stent geometries, is least likely to be associated with parameters correlated with pathobiologic responses leading to restenosis, in the case of curved coronary arteries, whose curvature changes significantly with each heart contraction. The stent geometries considered in this study correspond to a Palmaz-like stent, an Express-like stent, a Cypher-like stent, and a Xience-like stent. The biomechanical environment induced by each implanted stent is evaluated in terms of displacement magnitude, Von Mises stress, normal stress experienced by the intimal layer with implanted stent, and wall shear stress. Arterial walls are modeled as multi-layered structures: the intimal layer with the internal elastic laminae is modeled as a nonlinearly elastic membrane, while the media–adventitia complex is modeled as a 3D linearly elastic material. The Navier–Stokes equations for an incompressible, viscous fluid, are used to model the blood flow. Full, two-way coupling between the fluid and the structure, and between the thin and thick structure, is considered. To include the effects of the force exerted by the pericardium and heart muscle contractions, external force is applied to the coronary artery walls. Pulsatile boundary conditions were imposed at the inlet and outlet of the coronary segment, approximating measured diastolic coronary flow. The presence of an implanted stent was modeled by its impact on the mass and elasticity properties of the intimal layer where the stent is located. The stent material is modeled as a 316L stainless steel. A novel, loosely coupled partitioned scheme combined with an ALE approach was used to solve this nonlinear FSI problem. It was found that the Cypher-like stent geometry outperforms the other three stent geometries. The ranking from best to worst is as follows: Cypher-like stent, Express-like stent, Xience-like stent, Palmaz-like stent. It is conjectured that the sinusoidal horizontal stent struts and large cells associated with open-cell design, give rise to a stent geometry that conforms best to the native curved coronary artery, with smallest deviations in Von Mises stress and displacement from the nonstented curved coronary artery both during systole and diastole. To the best of our knowledge, this is the first computational study in which the behavior of different stent geometries implanted in curved coronary arteries is studied using full FSI capturing the behavior of multi-layered, curved, stented coronary arteries contracting on a beating heart. • Four stents contracting with the heart are considered. • A novel multi-layered arterial wall model is used. • A second-order accurate ALE-based FSI scheme is used. • The biomechanical environment induced by each stent is evaluated. [ABSTRACT FROM AUTHOR]

Poly(l -lactide) (PLLA) is an important candidate raw material of the next-generation biodegradable stent for percutaneous coronary intervention, yet how to make a polyester stent with sufficient mechanical strength and relatively fast biodegradation gets to be a dilemma. Herein, we put forward a hybrid interpenetrating network (H-IPN) strategy to resolve this dilemma. As such, we synthesize a multi-functional biodegradable macromer of star-like poly(d , l -lactide- co -ɛ-caprolactone) with six acrylate end groups, and photoinitiate it, after mixing with linear PLLA homopolymer, to trigger the free radical polymerization. The resultant crosslinked polymer blend is different from the classic semi-interpenetrating network, and partial chemical crosslinking occurs between the linear polymer and the macromer network. Combined with the tube blow molding and the postprocessing laser cutting, we fabricate a semi-crosslinked-polyester biodegradable coronary stent composed of H-IPN, which includes a physical network of polyester spherulites and a chemical crosslinking network of copolyester macromers and a part of homopolymers. Compared with the currently main-stream PLLA stent in research, this H-IPN stent realizes a higher and more appropriate biodegradation rate while maintaining sufficient radial strength. A series of polymer chemistry, polymer physics, polymer processing, and in vitro and in vivo biological assessments of medical devices have been made to examine the H-IPN material. The interventional implanting of the H-IPN stent into aorta abdominalis of rabbits and the follow-ups to 12 months have confirmed the safety and effectiveness. [ABSTRACT FROM AUTHOR]

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Dual antiplatelet therapy (DAPT) with a P2Y 12 receptor antagonist in addition to aspirin is the antiplatelet treatment of choice in patients undergoing percutaneous coronary intervention. Despite DAPT being one of the most widely investigated treatment strategies in the cardiology field, its optimal duration after coronary stenting remains controversial. The balance between the possible benefit of preventing a thrombotic event and the risk of suffering a bleeding complication due to maintenance of therapy is of critical relevance to determine the duration of DAPT in a given patient. Indeed, extended DAPT is associated with a reduction in non-fatal ischemic outcomes, at the cost of increasing the risk of bleeding events. Of note, several factors related to the patient, the procedure, or the device implanted may influence the ischemic and/or bleeding risk profiles of a given patient. Therefore, it is reasonable to recommend that the decision on DAPT duration should be individualized on a case-to-case basis. This review aims to provide a comprehensive overview of the current status of knowledge on duration of DAPT after coronary stenting, focusing on the evidence provided mainly by randomized clinical trials, as well as to discuss the factors that may influence the individual ischemic and bleeding risk profiles for a given patient, and whether the use of risk scores may inform the decision-making process for determining DAPT duration. [ABSTRACT FROM AUTHOR]

Direct oral anticoagulant (DOAC) use is growing as monotherapy and combined with platelet inhibitors. The safety of such combination therapy, especially in comparison to regimens including warfarin, in real world populations remains uncertain. We investigated hemorrhage associated with DOAC and antiplatelet combination therapy in a cohort of elderly coronary artery stent recipients. We employed Medicare data 2010–2013 for a 40% random sample of beneficiaries enrolled in inpatient, outpatient and prescription benefits. We used Cox proportional hazards models to examine the association of the combination anticoagulant (DOAC or warfarin) plus antiplatelets with major hemorrhage events (upper gastrointestinal or intracranial) in the 12 months following stent placement. We identified 70,900 stent recipients. 14.4% had atrial fibrillation (AF) diagnosis preoperatively. Among the 24.5 million observation days, exposure distribution was: 73.8% antiplatelets only, 4.7% antiplatelets plus warfarin, 0.6% antiplatelets plus DOAC, 2.2% warfarin only, 0.3% DOAC only and 18.4% no observed antiplatelets or anticoagulant. Overall, 8,029 patients (11.3%) experienced major hemorrhage. Among AF patients, compared to antiplatelets only, DOAC plus antiplatelets was associated with increased hemorrhage risk (HR, 1.94; 95%CI, 1.48–2.54); warfarin plus antiplatelets conferred comparable bleed risk (HR, 1.69; 95%CI, 1.47–1.94). In the non-AF group, compared to antiplatelets alone, combination DOAC plus antiplatelets (HR, 3.09; 95%CI, 2.15–4.46), and warfarin plus antiplatelets (HR, 2.21; 95%CI, 1.97–2.48) conferred greater bleed risk. Among elderly coronary artery stent recipients with AF, the two drug combinations, DOAC plus antiplatelets and warfarin plus antiplatelets, were associated with similarly increased risk of major hemorrhage compared to antiplatelets alone. [ABSTRACT FROM AUTHOR]

In silico studies to perform structural analyses of coronary stenting have attracted the attention of many researchers in the last 25 years. As a consequence, the finite element models used to describe the fundamental elements of stenting simulations, namely the delivery system (consisting of stent and balloon), the diseased artery, and the deployment procedure have had considerable development, paving the way for the application of numerical analyses in both manufacturing and clinical contexts. Indeed, in accordance with the logic of the 3Rs (refine, reduce, and replace), simulations can play a fundamental role in developing new devices and as a support tool for training/education and operational planning activities for clinical personnel. However, the application of such numerical methodologies in the aforementioned contexts of use requires an adequate level of credibility of the models with respect to the risk associated to their use in the decision-making process. Within this framework, this paper proposes a review of the modeling approaches available today for in silico stenting of coronary arteries and a discussion of their actual or potential application areas. In particular, the attention is focused on the different levels of credibility required by the presented contexts of use with respect to the validation activities of numerical models developed up to now. • Structural computational simulations are going to play a fundamental role in coronary stenting. • Advanced modeling techniques for delivery system, artery and procedure are available. • Structural finite element analyses may support new device development and clinical decisions. • Validation and context of use are crucial aspects for credibility assessment of computational models. [ABSTRACT FROM AUTHOR]

Treatment of coronary heart disease by percutaneous coronary intervention (PCT) is usually limited to the high restenosis rate after implantation of bare-metal stent. To solve the problem, the coating of PEGylated stereocomplex poly( l -lactide) (PEG−cPLA) was utilized on the surface modification of stainless steel (SS) sheet. Specifically, the 3-aminopropyltriethoxysilane (APTES)-modified methoxy-poly(ethylene glycol)−poly( d -lactide) (mPEG−PDLA) was grafted onto the surface of hydroxylated SS sheet through coupling reaction, and poly( l -lactide)−poly(ethylene glycol)−poly( l -lactide) (PLLA−PEG−PLLA) was coated onto the surface through stereocomplex interaction between DLA and LLA units. The increase of contact angle firstly confirmed the changes of surface composition and hydrophilicity for the PEG−scPLA-modified SS sheet. The decreased fibrinogen adsorption, down-regulated platelet activation, and improved adhesion of human umbilical vein endothelial cells (HUVECs) indicated the excellent biocompatibility of PEG−scPLA-modified SS sheet. In addition, the drug loading capability of SS sheet was greatly upregulated through the formation of scPLA coating on the surface, where fluorescein (FLU) was chosen as a model molecule. Overall, the surface modification of SS sheet with PEG−scPLA could enhance the comprehensive performances, such as biocompatibility and drug loading capability, demonstrating that PEG−scPLA is a promising coating of coronary stent for PCT. [ABSTRACT FROM AUTHOR]

Percutaneous transluminal coronary angioplasty (PTCA) is currently one of the most effective methods for treatment of coronary heart disease (CHD). It is widely accepted due to its micro trauma and high efficiency. However, restenosis will occur in 3–5 years after surgery. The emergence of drug eluting stent has greatly delayed the restenosis cycle. Therefore, it is becoming a hot spot and direction of the research how to effectively carry the anticoagulant drug to the surface of the stent. This paper introduces and summarizes the latest processing technology of micro/nano structure and to enhance its drug-loading ability on the surface of stent, analyzes the advantages and disadvantages of different processing technology. In addition, combined with the latest achievements of our research group, the paper looks forward to the prospect of using laser micro/nano structure processing on the coronary stent surface of drug-loaded. [ABSTRACT FROM AUTHOR]

Incomplete stent apposition (ISA, also known as malapposition) is a complication that affects day-to-day coronary stenting procedures. ISA is more prominent in complex arterial geometries, such as curvature, as a result of the limited conformability of coronary stents. These malapposed struts disturb the otherwise near-wall laminar blood flow and form a micro-recirculation environment. The micro-recirculation environment is often associated with low wall shear stress (WSS) and upsets the delicate balance of vascular biology, providing possible nidus for thrombosis and restenosis. In this study, a three-dimensional (3D) stent model was virtually deployed into an idealised curved coronary artery. Computational fluid dynamics (CFD) simulations were carried out to systematically analyse the haemodynamic effects of increasing maximum ISA distances, ranging from 180 (moderate), 400 (intermediate) to 910 μ m (severe) in an artery with decreasing radius of curvature (ROC). Micro-recirculations around both proximal and distal malapposed struts become more pronounced as compared to fully-apposed struts. The accompanying areas of low temporally-averaged WSS (AL-TAWSS) can increase twofold compared to the fully-apposed condition. Furthermore, substantial regions (∼5.2% and 9.0%) of AL-TAWSS are detached from the distal end of the malapposed struts in both moderate and intermediate cases respectively. Malapposed stents also induce more variation of TAWSS at the inner bend of the artery. At the stent surface, maximum WSS increases threefold from the fully-apposed case to intermediate ISA. High WSS on the strut surface is known to activate platelets which when exposed to the micro-recirculation environment may lead to their deposition and thrombosis. [ABSTRACT FROM AUTHOR]

Atrial fibrillation and coronary artery disease are common comorbidities with increasing incidences worldwide. About 5–15% of atrial fibrillation patients will require coronary stenting at some point in their lives, which necessitates dual antiplatelet therapy with aspirin and a P 2 Y 12 antagonist. Triple therapy refers to the clinical scenario in which a patient is prescribed aspirin, P 2 Y 12 antagonist, and oral anticoagulant, usually in the setting of atrial fibrillation. Current guidelines on atrial fibrillation do not offer strong recommendations on triple therapy management. Furthermore, the optimal duration of dual antiplatelet therapy after percutaneous coronary intervention is evolving based on contemporary research and development of newer generation drug eluting stents, changing the necessary duration of triple therapy in patients with atrial fibrillation. This review will offer an in-depth survey of current guidelines, current evidence, and future studies regarding triple therapy in atrial fibrillation patients undergoing percutaneous coronary intervention. [ABSTRACT FROM AUTHOR]

The noninferiority design is used extensively in current clinical research, but its complex features may hamper the appropriate interpretation of such trials. Thus, understanding the pillars of noninferiority design is indispensable. The authors discuss fundamental concepts regarding the design and interpretation of noninferiority trials and then explore some common methodological criticism by analyzing a sample of contemporary coronary stent trials. Finally, the authors give an overall perspective to enhance the design and conduct of future trials. [ABSTRACT FROM AUTHOR]

Thrombosis formation, restenosis, and delayed endothelium regeneration continue to be a challenge for coronary artery stent therapy. To improve the hemocompatibility of cardiovascular implants and to selectively direct vascular cell behavior, a novel heparin/poly- l -lysine microsphere was developed and immobilized on a dopamine-coated surface. We chose medical grade high nitrogen nickel-free austenitic stainless steel as the stent material since it has better biocompatibility. The stability and structural characteristics of the microspheres changed with the heparin: poly- l -lysine concentration ratio. Antithrombin III binding was significantly enhanced. Furthermore, for plasma coagulation tests, the activated partial thromboplastin time and thrombin time were prolonged and depended on the heparinfunction. The modified exhibited excellent stability and anticoagulant activity, and efficiently accelerated endothelialization and anticoagulation. This work has potential application for the design of coronary artery stent surfaces tailored for vascular cell behavior. [ABSTRACT FROM AUTHOR]

Undesirable deformation of the stent can induce a significant amount of injure not only to the blood vessel but also to the plaque. The objective of this study was to reduce/minimize these undesirable deformations by the application of Functionally Graded Materials (FGM). To do this, Finite Element (FE) method was employed to simulate the expansion of a stent and the corresponding displacement of the stenosis plaque. Three hyperelastic plaque types as well as five elastoplastic stents were simulated. Dogboning, foreshortening, maximum stress in the plaque, and the pressure which is needed to fully expand the stent for different stent materials, were acquired. While all FGMs had lower dogboning in comparison to the stents made of the uniform materials, the stent with the lowest heterogeneous index displayed the lowest amount of dogboning. Steel stent showed the lowest foreshortening and fully expansion pressure but the difference was much lower than that the one for dogboning. Therefore, the FGM with the heterogeneous index of 0.5 is expected to exhibit the most suitable results. In addition, the results revealed that the material parameters has crucial effects on the deformation of the stent and, as a result, as a design point of view the FGM parameters can be tailored to achieve the goal of the biomechanical optimization. [ABSTRACT FROM AUTHOR]

Bioresorbable scaffolds (BRS) represent a novel horizon in interventional cardiology for the treatment of coronary artery disease. The technology was introduced to overcome limitations of current metallic drug-eluting stents such as late in-stent restenosis and permanently caging the vessel. The concept of the BRS is to provide temporal support to the vessel during healing before being degraded and resorbed by the body, promoting restoration of the vessel vasomotion. Currently, there are several BRS that are under development or already commercially available. Although several reviews have elegantly covered progress of current clinical programs and newer scaffold technologies, little is available currently to describe the mechanistic differences between biomaterials used in current and newer bioresorbable technologies. This aim of this review is to discuss the status of the different BRS technologies and materials currently under investigation, explore the newer strategies being adopted to improve material mechanical properties and optimize BRS degradation and summarize the performance of BRS in the clinical setting so far. [ABSTRACT FROM AUTHOR]

Objectives This study sought to compare the 2-year outcomes between bioresorbable vascular scaffold (BVS) and everolimus-eluting metallic drug-eluting stent (EES). Background The occurrence of very late stent/scaffold thrombosis (VLST) of BVS beyond 1 year after implantation is an increasing concern. Methods We conducted a meta-analysis of 24 studies (BVS: n = 2,567 and EES: n = 19,806) reporting the 2-year outcomes of BVS and/or EES to compare the risk of BVS versus EES for stent/scaffold thrombosis (ST) and target lesion failure (TLF) in 7 comparative studies (3 randomized and 4 observational), and to estimate the pooled incidence rates of ST and TLF including additional 17 single-arm studies. Results In the 7 comparative studies, the risk for VLST between 1 and 2 years was numerically higher in BVS than in EES (odds ratio [OR]: 2.03 [95% confidence interval (CI): 0.62 to 6.71]). The excess risk of BVS relative to EES for ST through 2 years was significant (OR: 2.08 [95% CI: 1.02 to 4.26]). The risk for TLF was neutral between BVS and EES. In the 24 studies, the pooled estimated incidence rates of VLST, and ST through 2 years were higher in BVS than in EES (0.240 [95% CI: 0.022 to 0.608]% vs. 0.003 [95% CI: 0.000 to 0.028]%, and 1.43 [95% CI: 0.67 to 2.41]% vs. 0.56 [95% CI: 0.43 to 0.70]%, respectively). The corresponding rates for TLF were comparable between BVS and EES (1.88 [95% CI: 1.30 to 2.55]% and 1.78 [95% CI: 1.17 to 2.49]% and 7.90 [95% CI: 6.26 to 9.69]% and 7.49 [95% CI: 5.86 to 9.29]%, respectively). Conclusions In this meta-analysis, BVS as compared with EES was associated with higher risk for VLST between 1 and 2 years and ST through 2 years. [ABSTRACT FROM AUTHOR]

[Display omitted] Drug-eluting stents (DESs) are drug-coated vascular implants that inhibit smooth muscle cell proliferation and limit in-stent re-stenosis. However, traditional DESs release a single drug into the blood and cannot cope with complex mechanisms in atherosclerosis and body responses. The present study aimed to develop a novel multimodal stent by fabricating asymmetric coating with electrophoretic deposition and electrospinning. Herein, we use heparin-loaded alginate (Hep/Alg) and atorvastatin calcium-loaded polyurethane (AtvCa/PU) coatings on the stent luminal and abluminal surfaces, respectively. Scanning electron microscopy (SEM) micrographs showed that the alginate coatings had uniformity and thin thickness. Meanwhile, the PU fibers were formed without beads, with an acceptable diameter and suitable mechanical properties. PU nanofiber revealed minimal degradation in a 1-month study. The release of AtvCa and Hep continued for 8 days without a significant initial burst release. None of the stent coatings were cytotoxic or hemolytic, and PU nanofibers supported the survival of human umbilical endothelial cells (HUVEC) with high adhesion and flattened morphologies. The results indicate that electrophoretic deposition and electrospinning have significant potential for achieving asymmetric coating on stents and a promising approach for dual drug release for multimodal effects in vascular stent applications. [ABSTRACT FROM AUTHOR]

Corrosion control of bioabsorbable Mg alloy stents is an attractive topic in recent years. Biodegradable polymer modification is a potential anti-corrosion method, but cannot achieve the desired corrosion protection due to the high water permeability of biodegradable polymers. In this study, a strengthened corrosion control strategy is proposed: Graphene oxide (GO) was introduced into a poly(trimethylene carbonate) (PTMC) coating to improve its anti-corrosion performance. GO/PTMC composite coatings with different GO contents were applied to AZ31b Mg alloy surfaces, and the effect of GO content (0, 0.2, 1, 3, 6, and 10 wt%) on surface characteristics, corrosion resistance, and in vitro biosafety was investigated. The results showed that the increase of GO content in the PTMC coating (<6 wt%) could improve its corrosion resistance by prolonging the permeation path of solution. Meanwhile, the addition of GO (<6 wt%) had little negative effects on cytocompatibility and hemocompatibility. However, when the addition of GO exceeded 6 wt%, GO aggregated on the coating surface, resulting in the formation of new defects and a rapid decrease in corrosion resistance. The optimized sample (GO content: 6 wt%) had the highest impedance modulus of 8.9 × 107 Ω·cm2 at 0.1 Hz and good in vitro biocompatibility, which shows great potential for application in vascular stents. [Display omitted] • Biodegradable GO/PTMC composite coatings were prepared on AZ31b Mg alloy. • The introduction of GO can effectively improve the corrosion resistance of samples. • The performance of the coating is related to the content of GO in the coating. • The optimized GO/PTMC sample exhibited good biocompatibility in vitro. [ABSTRACT FROM AUTHOR]

Objectives To compare the direct costs of the index hospitalization and 30-day morbidity and mortality incurred during robotic and conventional coronary artery bypass grafting at a single institution based on hospital clinical and financial records. Design Retrospective study, propensity-matched groups with one-to-one nearest neighbor matching. Setting University hospital, a tertiary care center. Participants Two thousand eighty-eight consecutive patients who underwent primary coronary artery bypass grafting (CABG) from January 2007 to March 2012. Interventions One hundred forty-one matched pairs were created and analyzed. Measurements and Main Results Robotic CABG was associated with a decrease in operative time (5.61±1.1 v 6.6±1.15 hours, p<0.001), a lower need for blood transfusion (12.8% v 22.6%, p = 0.04), a shorter length of stay (6 [4-9]) v 7 [5-11] days, p = 0.001), a shorter ICU stay (31 [24-49] hours v 52 [32-96.5] hours, p<0.001) and lower NY state complications composite rate (4.26% v 13.48%, p = 0.01). In spite of that, the cost of robotic procedures was not significantly different from matched conventional cases ($18,717.35 [11,316.1-34,550.6] versus $18,601 [13,137-50,194.75], p = 0.13), except 26 hybrid coronary revascularizations in which angioplasty was performed on the same admission (hybrid 25,311.1 [18,537.1-41,167.85] versus conventional 18,966.13 [13,337.75-56,021.75], p = 0.02). Conclusion Robotically assisted CABG does not increase the cost of the index hospitalization when compared to conventional CABG unless hybrid revascularization is performed on the same admission. [ABSTRACT FROM AUTHOR]

In this study, we aimed to evaluate the mechanical effects of different stent linker designs on in-stent restenosis in porcine coronary arteries. We fabricated stents with an open-cell structure composed of nine main cells and three linker structures in model 1 (I-type), model 2 (S-types) and model 3 (U-types)) as well as Model 4, which is similar to a commercial bare metal stent design. The stent cells were 70 mm thick and wide, with a common symmetrical wave pattern. As the radial force increased, the number of main cells increased and the length of linker decreased. Radial force was higher in model 1, with a linear I-linker, than in models with S- or U-linkers. The flexibility measured by three-point bending showed a force of 1.09 N in model 1, 0.35 N in model 2, 0.19 N in model 3, and 0.31 N in model 4. The recoil results were similar in all models except model 4 and were related to the shape of the main cells. The foreshortening results were related to linker shape, with the lowest foreshortening observed in model 3 (U-linker). Restenosis areas in the porcine restenosis model 4 weeks after implantation were 35.4±8.39% (model 1), 30.4±7.56% (model 2), 40.6±9.87% (model 3) and 45.1±12.33% (model 4). In-stent restenosis rates measured by intravascular ultrasound (IVUS) and micro-computed tomography (micro-CT) showed similar trends as percent area stenosis measured by micro-CT. Model 2, with optimized flexibility and radial force due to its S-linker, showed significantly reduced restenosis in the animal model compared to stents with different linker designs. These results suggest that the optimal stent structure has a minimum radial force for vascular support and maximum flexibility for vascular conformability. The importance of the effects of these differences in stent design and their potential relationship with restenosis remains to be determined. [ABSTRACT FROM AUTHOR]

The duration of dual antiplatelet therapy (DAPT) after coronary stenting has been evaluated in randomized studies with apparently conflicting results. Although longer exposure associates with more bleeding complications, late stent thrombosis (ST) and myocardial infarction are reduced. In addition, as new drug-eluting stents carry a lower risk of ST compared with the first-generation drug-eluting stents and possibly even bare-metal stents, a shift toward better protection from ST may have an effect on the duration and intensity of DAPT. Whether the duration of DAPT should be shorter or longer than the currently recommended 6 to 12 months is analyzed in this review, drawing on lessons from the most recent studies. [ABSTRACT FROM AUTHOR]

Objectives This study examined whether coronary angioscopy-verified in-stent yellow plaque at 1 year after drug-eluting stent (DES) implantation is associated with future event of very late stent failure (VLSF). Background Atherosclerosis detected as yellow plaque by angioscopy has been associated with future events of acute coronary syndrome. Development of in-stent neoatherosclerosis is a probable mechanism of VLSF. Methods This study included 360 consecutive patients who received successful angioscopic examination at 1 year after implantation of a DES. They were clinically followed up for VLSF defined as cardiac death, acute myocardial infarction or unstable angina, or need for revascularization associated with the stent site. Results The follow-up interval was 1,558 ± 890 days (4.3 ± 2.4 years). The incidence of VLSF was significantly higher in the patients with yellow plaque than in those without (8.1% vs. 1.6%; log rank p = 0.02). Multivariable analysis revealed the presence of yellow plaque (hazard ratio [HR]: 5.38; p = 0.02) and absence of statin therapy (HR: 3.25; p = 0.02) as risks of VLSF. Conclusions In-stent atherosclerosis evaluated by yellow plaque at 1 year after the implantation of DES and the absence of statin therapy were risks of VLSF. The underlying mechanism of VLSF appeared to be the progression of atherosclerosis as demonstrated by the yellow plaque. [ABSTRACT FROM AUTHOR]

To enhance the corrosion resistance of bioabsorbable magnesium alloys, a Mg(OH) 2 /MgF x (OH) 1−x inorganic coating was prepared on a AZ31B magnesium alloy by a simple two-step immersion approach. The surface analysis, processing optimization, adhesion properties, in vitro corrosion behavior and biocompatibility were investigated. The composite coating significantly improved the adhesion of poly(trimethylene carbonate) coating on the surface (level 1). The corrosion resistance of the optimized sample was significantly improved (I corr =7.1 × 10−8 A·cm–2) due to the blocking of defects by the Mg(OH) 2 nanosheet. In addition, the optimized sample exhibited better in vitro cytocompatibility and hemocompatibility. • NaOH treatment blocked some defects of the hydrofluoric acid coating. • NaOH treatment improved the anti-corrosion performance of the coating. • NaOH treatment can improve the adhesive ability of polymers on its surface. • The modification has the advantages of simplicity, low-cost and nontoxicity. [ABSTRACT FROM AUTHOR]

Background Bifurcation lesions are frequent among patients with symptomatic coronary disease treated by percutaneous coronary intervention. Current evidence recommends a conservative (provisional) approach when treating the side branch (SB). Objectives The TRYTON (Prospective, Single Blind, Randomized Controlled Study to Evaluate the Safety & Effectiveness of the Tryton Side Branch Stent Used With DES in Treatment of de Novo Bifurcation Lesions in the Main Branch & Side Branch in Native Coronaries) bifurcation trial sought to compare treatment of de novo true bifurcation lesions using a dedicated bifurcation stent or SB balloon angioplasty. Methods We randomly assigned patients with true bifurcation lesions to a main vessel stent plus provisional stenting or the bifurcation stent. The primary endpoint (powered for noninferiority) was target vessel failure (TVF) (cardiac death, target vessel myocardial infarction, and target vessel revascularization). The secondary angiographic endpoint (powered for superiority) was in-segment percent diameter stenosis of the SB at 9 months. Results We randomized 704 patients with bifurcation coronary lesions at 58 centers (30 from Europe and 28 from the United States). At 9 months, TVF was 17.4% in the bifurcation stent group compared with 12.8% in the provisional group (p = 0.11), mainly because of a higher periprocedural myocardial infarction rate (13.6% vs. 10.1%, p = 0.19). The TVF difference of +4.6% (2-sided 95% confidence interval: −1.0 to 10.3; upper limit of the 1-sided 95% confidence interval: 10.3) was not within the pre-specified noninferiority margin of 5.5% (p = 0.42 for noninferiority). The SB in-segment diameter stenosis among the angiographic cohort was lower in the bifurcation stent group compared with the provisional group (31.6% vs. 38.6%, p = 0.002 for superiority), with no difference in binary restenosis rates (diameter stenosis ≥50%) at 9 months follow-up (22.6% vs. 26.8%, p = 0.44). Conclusions Provisional stenting should remain the preferred strategy for treatment of non–left main true coronary bifurcation lesions. (Prospective, Single Blind, Randomized Controlled Study to Evaluate the Safety & Effectiveness of the Tryton Side Branch Stent Used With DES in Treatment of de Novo Bifurcation Lesions in the Main Branch & Side Branch in Native Coronaries [TRYTON]; NCT01258972 ) [ABSTRACT FROM AUTHOR]

Background Recent coronary stent placement and noncardiac surgery contribute to the risk of adverse cardiac events, but the relative contributions of these two factors have not been quantified. Objectives This research was designed to determine the incremental risk of noncardiac surgery on myocardial infarction (MI) and coronary revascularization following coronary stenting. Methods A U.S. retrospective cohort study of patients receiving coronary stents at Veterans Affairs medical centers between 2000 and 2010 was used to match patients undergoing noncardiac surgery within 24 months of stent placement to two patients with stents not undergoing surgery. Patients were matched on stent type and cardiac risk factors present at the time of stent placement. A composite endpoint of MI and/or cardiac revascularization for the 30-day interval post-surgery was calculated. Adjusted risk differences (RD) were compared across time periods following stent implantation, using generalized estimating equations. Results We matched 20,590 surgical patients to 41,180 nonsurgical patients. During the 30-day interval following noncardiac surgery, the surgical cohort had higher rates of the composite cardiac endpoint (3.1% vs. 1.9%; RD: 1.3%; 95% confidence interval: 1.0% to 1.5%). The incremental risk of noncardiac surgery adjusted for surgical characteristics ranged from 3.5% immediately following stent implantation to 1% at 6 months, after which it remained stable out to 24 months. Factors associated with a significant reduction in risk following surgery more than 6 months post-stent included elective inpatient procedures (ΔRD: 1.8%; p = 0.01), high-risk surgery (ΔRD: 3.7%; p = 0.01), and drug-eluting stent (DES) (ΔRD: 1.3%; p = 0.01). Conclusions The incremental risk of noncardiac surgery on adverse cardiac events among post-stent patients is highest in the initial 6 months following stent implantation and stabilizes at 1.0% after 6 months. Elective, high-risk, inpatient surgery, and patients with DES may benefit most from delay from a 6-month delay after stent placement. [ABSTRACT FROM AUTHOR]

Adverse effects of nickel ions being released into the living organism have resulted in development of high nitrogen nickel-free austenitic stainless steels for medical applications. Nitrogen not only replaces nickel for austenitic structure stability but also improves steel properties. The cell cytocompatibility, blood compatibility and cell response of high nitrogen nickel-free austenitic stainless steel were studied in vitro. The mechanical properties and microstructure of this stainless steel were compared to the currently used 316L stainless steel. It was shown that the new steel material had comparable basic mechanical properties to 316L stainless steel and preserved the single austenite organization. The cell toxicity test showed no significant toxic side effects for MC3T3-E1 cells compared to nitinol alloy. Cell adhesion testing showed that the number of MC3T3-E1 cells was more than that on nitinol alloy and the cells grew in good condition. The hemolysis rate was lower than the national standard of 5% without influence on platelets. The total intracellular protein content and ALP activity and quantification of mineralization showed good cell response. We conclude that the high nitrogen nickel-free austenitic stainless steel is a promising new biomedical material for coronary stent development. [ABSTRACT FROM AUTHOR]

In many computational fluid dynamics (CFD) studies of stented vessel haemodynamics, the geometry of the stented vessel is described using non-deformed (NDF) geometrical models. These NDF models neglect complex physical features, such as stent and vessel deformation, which may have a major impact on the haemodynamic environment in stented coronary arteries. In this study, CFD analyses were carried out to simulate pulsatile flow conditions in both NDF and realistically-deformed (RDF) models of three stented coronary arteries. While the NDF models were completely idealised, the RDF models were obtained from nonlinear structural analyses and accounted for both stent and vessel deformation. Following the completion of the CFD analyses, major differences were observed in the time-averaged wall shear stress (TAWSS), time-averaged wall shear stress gradient (TAWSSG) and oscillatory shear index (OSI) distributions predicted on the luminal surface of the artery for the NDF and RDF models. Specifically, the inclusion of stent and vessel deformation in the CFD analyses resulted in a 32%, 30% and 31% increase in the area-weighted mean TAWSS, a 3%, 7% and 16% increase in the area-weighted mean TAWSSG and a 21%, 13% and 21% decrease in the area-weighted mean OSI for Stents A, B and C, respectively. These results suggest that stent and vessel deformation are likely to have a major impact on the haemodynamic environment in stented coronary arteries. In light of this observation, it is recommended that these features are considered in future CFD studies of stented vessel haemodynamics. [ABSTRACT FROM AUTHOR]

Through decades of use and refinement, endovascular stents have become part and parcel of the manage-ment of obstructive atherosclerotic lesions. Upon stent placement, a variety of biophysical reactions ensue, governed not only by the mechanical and material properties of the device, but also the impact these properties have on the local vascular biology. Anatomic changes and vascular deformations give rise to solid mechanical and fluid forces that are the proximate, functional drivers of the induced reparative response. Powerful computational tools and advanced imaging techniques allow us to define these forces with high precision and increasingly, at a patient-specific level. We have also gained fundamental insights into how these forces influence subcellular and cellular processes, and, through application of a variety of model systems, how they subsequently drive an integrated tissue response. Clinical studies extend understanding to actual patients and pathophysiologic scenarios. These tools and insights take on added weight given the real risks that accompany the many substantial benefits of stenting. Complex lesions remain difficult to manage and continue to be associated with worse outcomes. While many patients respond well to treatment, others suffer treatment failures and recurrent events - sometimes catastrophic. Overcoming such variability requires that we move towards individualized treatment plans. Doing so necessitates that we develop not just a qualitative understanding of involved phenomena, but a quantitative ability to predict integrated outcomes. Given the multi-scale nature of the vascular response to stenting, it is critical that models, be they computational, bench-top, animal, or clinical, can be verified, validated, and made interrelated. This review provides an overview of the biophysics governing endovascular stenting, their integration in real-world endovascular settings, and how simulation and statistical approaches are helping to bridge the gap between qualitative model understanding and quantitative clinical prediction. [ABSTRACT FROM AUTHOR]

Abstract: Background: Reliability of coronary angiography by multidetector row CT (MDCT-CA) for stent evaluation is still a matter for debate, and it is unknown whether contrast medium characteristics may affect diagnostic performance of MDCT-CA. Objective: We compared iomeprol-400 with iodixanol-320 to evaluate coronary stents with MDCT-CA. Methods: We randomly assigned 254 patients undergoing coronary stent follow-up with the use of MDCT-CA to iomeprol-400 at 5.0 mL/sec flow rate (group 1; n = 83), iodixanol-320 at 6.2 mL/sec flow rate (group 2; n = 87), and iodixanol-320 at 5.0 mL/sec flow rate (group 3; n = 84). Heart rate (HR) immediately before and at the end of scanning, HR variation, premature heart beats, and heat sensation by visual analog scale during scanning were recorded. Mean attenuation was measured in the aortic root and coronary arteries. Image quality score and type of artifacts were assessed. Results: Mean attenuation was significantly lower in group 3 than in the other groups. In group 3, stent evaluability was significantly higher and artifact rate was significantly lower than in group 2 (99% vs 91% and 4% vs 15%) and group 1 (99% vs 92% and 4% vs 17%), respectively, mainly because of a significant lower rate of beam-hardening artifacts (3 cases in group 3 vs 22 and 27 in groups 2 and 3, respectively). In group 3, visual analog scale, HR at the end of imaging, and number of patients with premature heart beats during the scan were significantly lower than in the other groups. Conclusions: Iodixanol-320 provides better image quality of coronary stents, allowing higher MDCT-CA evaluability, than iomeprol-400. [Copyright &y& Elsevier]

Abstract: Background: Outcome of sirolimus-eluting stent (SES) in patients treated with an antivitamin K (VKA) agent before the PCI procedure is unknown. Methods: A total of 7651 patients were selected among 15,147 recipients of SES, included in the worldwide e-SELECT registry, only from those centers which included at least one patient requiring VKA: 296 were pretreated with a VKA agent (VKA group), whereas 7355 patients from the same enrolling medical centers were not (NON-VKA group). The rates of 1) major adverse cardiac events (MACE), including all-cause deaths, myocardial infarction (MI) and target lesion revascularization, 2) stent thrombosis (ST) and 3) major bleeding (MB) in the 2 study groups were compared at 1, 6 and 12months. Results: The patients in VKA group were on average older as compared to those in NON-VKA group (67.7±9.9 vs.62.9±10.7, P <0.001). The indications for pre-procedural anticoagulation were atrial fibrillation in 177 (59.8%), presence of a prosthetic valve in 21 (7.1%), embolization of cardiac origin in 17 (5.7%), pulmonary embolism or deep vein thrombosis in 17 (5.7%), and miscellaneous diagnoses in 64 (21.6%) patients. At 1year, the rates of MACE and MB were higher in the VKA vs. the NON-VKA group (8.3% and 3% vs. 5.3% and 1.2%, P <0.04and P <0.002, respectively). The 1-year rates of definite and probable ST were remarkably low in both groups (0.38% vs. 1.1%, p=0.4). Conclusions: Selected patients anticoagulated with VKA agent may safely undergo SES implantation. Those patients may receive a variety of APT regimen at the cost of a moderate increased risk of MB. [Copyright &y& Elsevier]

Abstract: Objective: Patients with coronary artery disease (CAD) often have prior stroke or concomitant extra-cardiac vascular disease (EVD) such as cerebral, aortic, or peripheral vascular disease. However, clinical outcomes after coronary revascularization in patients with polyvascular disease have not been fully elucidated. Methods: Among 15,263 patients undergoing first coronary revascularization enrolled in the CREDO-Kyoto registry Cohort-2 from January 2005 to December 2007, there were 1443 patients with prior stroke (stroke + CAD group), 974 patients with EVD (EVD + CAD group), 253 patients with both prior stroke and EVD (stroke/EVD/CAD group) and 12,593 patients with neither prior stroke nor EVD (CAD alone group [reference]). Results: The cumulative incidence of major adverse cardiovascular events (MACE: composite of cardiovascular death, myocardial infarction and stroke) through 3 years was significantly higher in patients with polyvascular disease compared with reference patients (19.9% in the stroke + CAD group, 18.5% in the EVD + CAD group, 20.1% in the stroke/EVD/CAD group, and 11.2% in the CAD alone group, P < 0.0001). After adjusting confounders, the presence of EVD and/or stroke was independently associated with higher risk for MACE compared with the reference group (adjusted HR [95%CI]: 1.34 [1.17–1.54], P < 0.0001 in the stroke + CAD group, 1.56 [1.32–1.84], P < 0.0001 in the EVD + CAD group, and 1.66 [1.24–2.23], P = 0.0007 in the stroke/EVD/CAD group). However, the presence of EVD and/or stroke was not associated with higher risk for myocardial infarction. Conclusions: Clinical outcome after coronary revascularization was worse in patients with prior stroke and/or EVD, which was mainly driven by the increased risk for non-coronary cardiovascular events. [Copyright &y& Elsevier]

The considerable progress in P2Y12-platelet blockers has important perioperative implications due to a family of novel agents beyond clopidogrel. Although prasugrel is more potent than clopidogrel due to more efficient hepatic metabolism, it is limited clinically by its irreversibility and bleeding risks. Ticagrelor, as the first approved direct and reversible oral P2Y12 blocker, still is limited clinically by its novel side-effect profile. Intravenous reversible P2Y12 blockade is possible now with both cangrelor and elinogrel, although both agents are still in clinical development. Furthermore, elinogrel offers the possibility of both oral and parenteral P2Y12 blockade with a single agent. Future trials likely will continue to evaluate and compare the safety and efficacy of these agents in multiple clinical settings, including the perioperative period. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To investigate the accuracy of 128-slice dual-source CT using high-pitch spiral mode (HPS) for the assessment of coronary stents. Methods: We conducted a prospective study on patients with previous stent implantation due to recurred suspicious symptoms of angina with positive findings at stress testing scheduled for coronary angiography (CA), while dual source computed tomography (DSCT) examinations were randomly done by one of the three different scan modes [HPS, sequential mode (SEQ), low-pitch spiral mode (LPS)] one week before CA examinations. The image quality, radiation dose and stent patency of DSCT were evaluated blinded to the results of CA. Results: 180 patients with total 256 stents were enrolled in this study. There was no significant difference on the image quality of DSCT by HPS (1.4±0.5), SEQ (1.5±0.5) and LPS (1.3±0.6) (P >0.05). The noise of images reconstructed with B26f kernel in HPS is significantly increased than in SEQ/LPS (P <0.05), while no significant difference with images reconstructed with B46f kernel (P >0.05). Heart rate (HR) variability had a slight impact on the image quality for HPS (P <0.05), not for LPS/SEQ (P >0.05). In the assessment of stent restenosis compared with CA on per-stent basis, there was no significant difference on sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of DSCT using HPS (100%, 97.1%, 83.3%, 100%), LPS (92.3%, 95.9%, 80%, 98.6%) and SEQ (93.3%, 97.3%, 87.5%, 98.6%) (P >0.05). The effective dose of DSCT by HPS (1.0±0.5mSv) is significant less than that by SEQ (3.0±1.4mSv) or LPS (13.0±5.4mSv) (P <0.01). Conclusions: DSCT using HPS provides good diagnostic accuracy on coronary stent patency compared with CA, similar to that by SEQ/LPS, whereas with lower effective dose in patients with HR lower than 65bpm. [Copyright &y& Elsevier]

Abstract: Bare metal and drug-eluting coronary stents suffer an inherent lack of vascular cell and blood compatibility resulting in adverse patient responses. We have developed a plasma-activated coating (PAC) for metallic coronary stents that is durable, withstands crimping and expansion, has low thrombogenicity and can covalently bind proteins, linker-free. This has been shown to enhance endothelial cell interactions in vitro and has the potential to promote biointegration of stents. Using the rabbit denuded iliac artery model, we show for the first time that PAC is a feasible coating for coronary stents in vivo. The coating integrity of PAC was maintained following implantation and expansion. The rate of endothelialization, strut coverage, neointimal response and the initial immune response were equivalent to bare metal stents. Furthermore, the initial thrombogenicity caused by the PAC stents showed a reduced trend compared to bare metal stents. This work demonstrates a robust, durable, non-cytotoxic plasma-based coating technology that has the ability to covalently immobilize bioactive molecules for surface modification of coronary stents. Improvements in the clinical performance of implantable cardiovascular devices could be achieved by the immobilization of proteins or peptides that trigger desirable cellular responses. [Copyright &y& Elsevier]

Abstract: The aim of this article is not to present a general academic review on primary angioplasty in patients with ST-elevation myocardial infarction, but rather to focus on some practical points that directly concern cardiologists who perform primary percutaneous interventions in these patients. We detail recent data about the use of the radial artery approach, thromboaspiration, new oral inhibitors of P2Y12, selective use of anti-GPIIb/IIIa, high dose of peri-procedural statin therapy, choice of the best stent, and the best approach for treating non-culprit lesions in patients with multivessel coronary artery disease. The changes observed in the overall management of patients undergoing primary PCI for ST-elevation myocardial infarction are likely to have participated in the decrease in mortality observed in several registries. New European guidelines on the management of STEMI, taking into account these diverse aspects, have just been published. [Copyright &y& Elsevier]

Abstract: Background: When patients with drug-eluting stents (DES) present for surgery, current guidelines recommend delaying elective surgeries until 1 year of dual antiplatelet therapy has been completed. Methods: We performed a systematic literature review of the major adverse cardiac events (MACE) associated with noncardiac surgery in patients with DES. Results: Twenty-eight of 358 studies met inclusion criteria. Overall, MACE rates decreased as time to surgery increased and varied from 0% to 18% for surgeries within 1 year as compared with 0% to 12% for surgery more than 1 year after a stent. In addition, the current literature showed limited evidence for a protective effect of continuing perioperative dual antiplatelet therapy on MACE rates. Conclusions: The current literature supports a significant decrease in MACE when surgery is performed 1 year after DES placement; however, the level of evidence is weak. Larger studies are needed to determine the safe interval for surgery after stent placement. [Copyright &y& Elsevier]

Optical coherence tomography (OCT), is a novel intravascular imaging modality analogous to intravascular ultrasound but uses light instead of sound. This review details the background, development, and status of current investigation using OCT, and discusses advantages, limitations, and likely future developments. It provides indications for possible future clinical use, and places OCT in the context of current intravascular imaging in what is a rapidly changing field of investigation. [ABSTRACT FROM AUTHOR]