cardiovascular-agents and Hyperplasia

Arteriovenous fistula (AVF) stenosis is a common problem leading to dialysis access dysfunction. The conventional balloon (CB) is the most commonly used device during angioplasty but suffers from poor durability of results due to neointimal hyperplasia-mediated recurrence. The drug-coated balloon (DCB) is an adjunct to balloon angioplasty that reduces neointimal hyperplasia, thereby improving post-angioplasty patency. Despite the heterogeneity of DCB clinical trials to date, the evidence suggests that DCBs of different brands are not necessarily equal, and that patient selection, adequate lesion preparation and proper DCB procedural technique are important to realize the benefit of DCB angioplasty.

Topics: Angioplasty, Balloon; Arteriovenous Fistula; Arteriovenous Shunt, Surgical; Cardiovascular Agents; Coated Materials, Biocompatible; Constriction, Pathologic; Graft Occlusion, Vascular; Humans; Hyperplasia; Paclitaxel; Renal Dialysis; Time Factors; Treatment Outcome; Vascular Access Devices; Vascular Patency

Topics: Cardiovascular Agents; Drug-Eluting Stents; Humans; Hyperplasia; Neointima; Tunica Intima

Restenosis by myointimal hyperplasia after peripheral arterial angioplasty or stenting often limits long term patency. Drug-eluting balloons (DEBs) which inhibit the proliferation of neo-intimal growth of vascular smooth muscle cells may prevent restenosis. The aim of this paper was to examine the evidence in published literature on the use of DEBs in the treatment of peripheral arterial in-stent restenosis (ISR).. A systematic literature review was undertaken of all published literature on the treatment of peripheral ISR with drug eluting balloon using Medline and cross-referenced. All published papers on the use of DEBs in peripheral arterial disease (PAD) were used. Cochrane Central Register of Controlled Trials and electronic databases were also searched for on-going studies.. There were no level 1 or 2 evidence published on this subject. The number of high-quality publications is few, and consequently a sufficient analysis is not possible. Recently data from non-randomized cohort studies showed encouraging results with DEB as treatment modality for ISR, whether used alone or as combined strategies.. Evidence from the published literature suggests that DEBs are safe in preventing peripheral ISR. Despite strong corporate pressure for the use of DEBs, there is only circumstantial evidence that this is a useful modality for ISR. Results from on-going studies may allow further meta-analysis for efficiency and cost-effectiveness.

Topics: Angioplasty, Balloon; Animals; Cardiovascular Agents; Humans; Hyperplasia; Lower Extremity; Neointima; Peripheral Arterial Disease; Recurrence; Retreatment; Stents; Treatment Outcome; Vascular Access Devices; Vascular Patency

Bioresorbable scaffolds have emerged as a potential alternative to non-erodible metal implants to alleviate the long-term risk of permanent device vascular implant-related adverse events. Bioresorbable scaffolds provide a temporary mechanical support function until the vessel reaches complete healing, and the implant progressively disappears and vasomotion resumes. A polymer matrix with embedded drugs coated onto the scaffold surface degrades slowly, reducing the size from the exterior toward the interior, and this allows controlled drug release to a local vascular segment. Drug elution from a bioresorbable scaffold system is characterized by a rapid initial release that achieves high concentration along the intimal surface, which is designed to prevail vascular dilation-induced injury and formation of neointimal hyperplasia. This review highlights diverse types of bioresorbable biomaterials as vascular scaffolds, drug release kinetics, adaptive arterial wall remodeling, and complexities in the advancement of vascular scaffolds to treat restenosis.

Topics: Absorbable Implants; Animals; Cardiovascular Agents; Coated Materials, Biocompatible; Delayed-Action Preparations; Drug Liberation; Endovascular Procedures; Humans; Hyperplasia; Kinetics; Neointima; Prosthesis Design; Recurrence; Risk Factors; Treatment Outcome; Vascular Diseases; Vascular Remodeling

Currently, endovascular therapy is the standard of care for peripheral artery disease. The main issue of these techniques is restenosis which is a complex mechanism associating elastic recoil, constrictive remodelling and intimal hyperplasia. More and more evidence show that drug-coating balloon (DCB) is a promising device to prevent and to treat restenosis. Herein we have reviewed the role for DCB's in the treatment of in-stent restenosis (ISR).. Currently, few studies are available regarding DCB use for femoropopliteal (FP) ISR treatment. In different studies evaluating DCB for treatment of FP ISR the freedom from target lesion revascularization rate at one year are range from 87% to 92.1%. In comparison to other devices used for treatment of FP ISR such as atherectomy, cutting balloon, standard angioplasty, DCB seems to show better results in terms of freedom from TLR and primary patency. Other devices such as drug-eluting stent, brachytherapy, covered stent show also good results for FP ISR.. Majority of assessed data on FP ISR treated with DCB derived from uncontrolled study or historical comparisons. Only one randomized, controlled study compared DCB versus standard angioplasty. The FAIR trial showed better results in favour of DCB in terms of freedom from TLR at 12 months (90.8%).. Drug coating balloon could be the first choice of devices for the treatment of FP ISR, because of its efficacy, its ease of use in comparison with more complex and less efficient devices.

Topics: Angioplasty, Balloon; Cardiovascular Agents; Coated Materials, Biocompatible; Constriction, Pathologic; Endovascular Procedures; Femoral Artery; Humans; Hyperplasia; Neointima; Peripheral Arterial Disease; Popliteal Artery; Recurrence; Retreatment; Risk Factors; Stents; Time Factors; Treatment Outcome; Vascular Access Devices

Leptin has received much attention since its cloning in 1994. Initially, leptin research centered on satiety, energy balance and sympathetic activation. However, hyperleptinemia has since been identified as an independent risk factor for various cardiovascular pathologies including atherosclerotic coronary artery disease. Over the last decade, multiple studies have implicated leptin as an important mediator in endothelial dysfunction and neointimal hyperplasia, both key steps in the evolution of atherosclerotic vascular changes. Additionally, more recent evidence indicates that paracrine leptin release from perivascular adipose tissue (PVAT) has deleterious effects on the underlying endothelium and vascular smooth muscle cells (SMC), including the coronary circulation. This report reviews pertinent literature on leptin-mediated endothelial dysfunction, SMC proliferation and the role of PVAT-derived leptin with an emphasis on the coronary circulation and discussions of currently proposed molecular mechanisms of PVAT-mediated coronary endothelial dysfunction and neointimal hyperplasia.

Topics: Adipose Tissue; Animals; Atherosclerosis; Cardiovascular Agents; Down-Regulation; Endothelium, Vascular; Humans; Hyperplasia; Leptin; Models, Cardiovascular; Molecular Targeted Therapy; Systemic Vasculitis; Tunica Intima; Up-Regulation

Despite significant advances in vascular biology, bioengineering, and pharmacology, restenosis remains a limitation to the overall efficacy of vascular reconstructions, both percutaneous and open. Although the pathophysiology of intimal hyperplasia is complex, a number of drugs and molecular tools have been identified that can prevent restenosis. Moreover, the focal nature of this process lends itself to treatment with local drug administration. This article provides a broad overview of current and future techniques for local drug delivery that have been developed to prevent restenosis after vascular interventions.. A systematic electronic literature search using PubMed was performed for all accessible published articles through September 2012. In an effort to remain current, additional searches were performed for abstracts presented at relevant societal meetings, filed patents, clinical trials, and funded National Institutes of Health awards.. The efficacy of local drug delivery has been demonstrated in the coronary circulation with the current clinical use of drug-eluting stents. Until recently, however, drug-eluting stents were not found to be efficacious in the peripheral circulation. Further pursuit of intraluminal devices has led to the development of balloon-based technologies, with a recent surge in trials involving drug-eluting balloons. Early data appear encouraging, particularly for treatment of superficial femoral artery lesions, and several devices have recently received the Conformité Européene mark in Europe. Investigators have also explored the periadventitial application of biomaterials containing antirestenotic drugs, an approach that could be particularly useful for surgical bypass or endarterectomy. In the past, systemic drug delivery has been unsuccessful; however, there has been recent exploration of intravenous delivery of drugs designed specifically to target injured or reconstructed arteries. Our review revealed a multitude of additional interesting strategies, including >65 new patents issued during the past 2 years for approaches to local drug delivery focused on preventing restenosis.. Restenosis after intraluminal or open vascular reconstruction remains an important clinical problem. Success in the coronary circulation has not translated into solutions for the peripheral arteries. However, our literature review reveals a number of promising approaches, including drug-eluting balloons, periadventitial drug delivery, and targeted systemic therapies. These and other innovations suggest that the future is bright and that a solution for preventing restenosis in peripheral vessels will soon be at hand.

Topics: Animals; Cardiac Catheters; Cardiovascular Agents; Coronary Restenosis; Coronary Stenosis; Drug Carriers; Drug-Eluting Stents; Endovascular Procedures; Equipment Design; Humans; Hyperplasia; Neointima; Percutaneous Coronary Intervention; Peripheral Vascular Diseases; Secondary Prevention; Treatment Outcome; Vascular Access Devices

Cardiovascular diseases (CVD) are one of the leading causes of death across the globe. Pathogenesis of coronary artery disease (CAD) is lead by the progression of atherosclerotic lacerations in coronary arteries. Percutaneous coronary intervention (PCI) using balloon angioplasty was introduced in 1979 and was majorly used in the treatment of these lesions. Introduction of bare metal stents (BMS) has revolutionized stenting procedures overcoming elastic recoil and reducing restenosis commonly associated with balloon angioplasty, but follow up studies have shown 20-30% prevalence of in-stent restenosis (ISR), this led to the development of drug eluting stents (DES). But long-term follow up studies have shown increased liability of stent thrombosis. Boosting the development of safer and effective DES expounding for therapies like biodegradable polymer based DES, polymer free DES, bioresorbable DES and combination DES to collectively reduce neointimal hyperplasia and promote endothelial healing. In dual-DES development, a combination employing an anti-restenotic agent (for preventing VSMC's proliferation), which is released for the first few weeks, and then the second drug a pro-healing agent (promoting re-endothelialization) released after a month would be ideal. Growing understanding in the areas of polymer therapeutics, nanoscale surface modifications and gene therapy would assist in the delivery of multiple drugs, which would further help in the design of promising therapeutic strategies for the treatment of CAD using stent based therapies.

Topics: Angioplasty, Balloon, Coronary; Animals; Cardiovascular Agents; Coronary Artery Disease; Coronary Restenosis; Coronary Thrombosis; Drug Carriers; Drug Combinations; Drug-Eluting Stents; Humans; Hyperplasia; Neointima; Prosthesis Design; Time Factors; Treatment Outcome; Wound Healing

Exaggerated neointimal hyperplasia is considered as the primary mechanism for increased restenosis in patients with diabetes mellitus (DM) treated with bare-metal stent. However, the vessel response in DM and non-DM treated with different drug-eluting stents (DES) has not been systematically evaluated.. We investigated 3D intravascular ultrasound (postprocedure and 6 to 9 months) in 971 patients (267 with DM and 704 without DM) treated with sirolimus- (n=104), paclitaxel- (n=303), zotarolimus- (n=391), or everolimus- (n=173) eluting stents. Volumetric data were standardized by length as volume index (VI). At postprocedure, lumen VI at the stented segment was significantly smaller in DM than in non-DM, whereas vessel VI was similar between the 2 groups. At follow-up, neointimal obstruction and maximum cross-sectional narrowing (neointimal area/stent area) were not significantly different between the 2 groups with no interaction for the DES type. Consequently, lumen VI was smaller in DM than in non-DM at follow-up. In the reference segments, residual plaque burden at postprocedure was significantly greater in DM than in non-DM, although change in lumen VI was similar between the 2 groups. The arterial responses at the reference segments also showed no interaction for the DES type.. DM and non-DM lesions showed similar vessel response in both in-stent and reference segments regardless of the DES type. In the DES era, the follow-up lumen in DM patients seems to be determined primarily by the smaller lumen at postprocedure rather than exaggerated neointima within the stent or plaque proliferation at the reference segments.

Topics: Aged; Angioplasty, Balloon, Coronary; Cardiovascular Agents; Chi-Square Distribution; Coronary Angiography; Coronary Artery Disease; Coronary Restenosis; Coronary Vessels; Diabetes Mellitus; Drug-Eluting Stents; Everolimus; Female; Humans; Hyperplasia; Linear Models; Male; Middle Aged; Multicenter Studies as Topic; Multivariate Analysis; Neointima; Paclitaxel; Predictive Value of Tests; Prosthesis Design; Randomized Controlled Trials as Topic; Retrospective Studies; Risk Factors; Sirolimus; Time Factors; Treatment Outcome; Ultrasonography, Interventional

Since the first clinical angioplasty by Gruntzig in 1977, restenosis has been the primary drawback of percutaneous coronary intervention (PCI). In the balloon era. restenosis was correlated with elastic recoil and negative remodeling of the arterial wall. Later, introduction of stents proved to be a significant advance in reducing the elastic recoil and negative remodeling at the treatment site but stimulated proliferation, migration of smooth muscle cells, and neointimal hyperplasia, thereby generating a new type of restenosis, in-stent restenosis. Brachytherapy and drug-eluting stents (DES) may be considered the two breakthroughs against neointimal hyperplasia. However, concerns about stent thrombosis and incomplete elimination of in-stent restenosis with DES in complex lesions and patients justify the pursuit of research in this field. Non-stent based local drug delivery and particularly the use of paclitaxel-eluting balloons could be one of these strategies. We aimed to review the concept, preclinical-, and clinical data available with non-stent based local drug delivery and, in particular, with paclitaxel-eluting balloons.

Topics: Angioplasty, Balloon, Coronary; Animals; Cardiovascular Agents; Coronary Restenosis; Coronary Stenosis; Drug-Eluting Stents; Equipment Design; Humans; Hyperplasia; Paclitaxel; Prosthesis Design; Thrombosis; Treatment Outcome

The incidence of restenosis after percutaneous peripheral interventions (PPI) varies considerably depending upon the vascular bed but appears to be highest in the femoropopliteal and tibioperoneal arteries. The restenosis process in the periphery does not appear to stop at the 6-month mark, as seen with bare metal stents in the coronary arteries, but continues for a longer time, possibly years, after the intervention. This review evaluates the incidence of restenosis following lower extremity arterial interventions and potential drugs or devices that could alter this process, including nonpharmacological (stents, cryoplasty, Cutting Balloon angioplasty, atherectomy, brachytherapy, and photodynamic therapy) and pharmacological (systemic and direct drug delivery) approaches. A global strategy to achieve optimal outcome with PPI is offered: (1) obtain excellent acute angiographic results with less dissection and recoil, (2) protect the distal tibial vascular bed, and (3) reduce smooth muscle cell proliferation with pharmacological intervention.

Topics: Angioplasty, Balloon; Arterial Occlusive Diseases; Atherectomy; Brachytherapy; Cardiovascular Agents; Cell Proliferation; Constriction, Pathologic; Cryotherapy; Humans; Hyperplasia; Lower Extremity; Muscle, Smooth, Vascular; Photochemotherapy; Practice Guidelines as Topic; Secondary Prevention; Stents; Treatment Outcome

Regardless of the type of arterial reconstruction, luminal narrowing (stenosis or restenosis) develops in approximately one third of the vessels. In the past, the focus of research has been on the mechanisms of stenosis (intimal hyperplasia, pathologic remodeling) and pharmacologic approaches to prevention. An alternative approach is to induce intimal atrophy after luminal narrowing has developed, thus limiting treatment to only those patients that develop a problem. This approach to treat established disease by reducing wall mass through induction of cell death and extracellular matrix removal would be particularly useful for treating stenosis in synthetic bypass grafts or stented vessels, in which intimal hyperplasia is the primary mechanism of stenosis. This approach may be applicable as well to other vascular proliferative disorders, such as pulmonary hypertension and chronic transplant arteriopathy. Proof of principle has been shown in experiments with antibodies to platelet-derived growth factor (PDGF) receptors that cause neointimal regression in baboon polytetrafluoroethylene (PTFE) grafts and with angiotensin-converting enzyme inhibitors that induce medial atrophy in hypertensive arteries. Possible molecular targets could include PDGF receptors, A20, and BMP4. Further studies are needed to determine the utility of such a therapeutic approach to vascular disease.

Topics: Animals; Arterial Occlusive Diseases; Atrophy; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Blood Vessels; Cardiovascular Agents; Cell Death; Cell Proliferation; Constriction, Pathologic; Coronary Disease; Disease Models, Animal; Heart Transplantation; Humans; Hyperplasia; Hypertension; Hypertrophy; Recurrence; Remission Induction; Signal Transduction; Stents

Although major advances have been made in the prevention and treatment of restenosis following coronary and peripheral interventions, the persistent complications of thrombosis and reintervention remain a mainstay for repeat hospitalizations in this patient population. For many years, a ubiquitous cell surface receptor called alpha(v)beta(3) integrin was the target of investigators in the prevention of restenosis because its interaction with the extracellular matrix was believed to coordinate the migration of smooth muscle cells (SMCs) from the media to the intima, the seminal event in the formation of intimal occlusive lesion. After the publication of uniformly positive animal studies demonstrating that alpha(v)beta(3) integrin blockade led to a significant reduction in new intimal (neointimal) lesion formation, early clinical trials supported the association of avoidance of target lesion revascularization and the use of antagonists to the SMC integrin alpha(v)beta(3) and its related platelet integrin alpha(IIb)beta(3). However, a series of clinical trials subsequently demonstrated that these antagonists did not necessarily prevent revascularizations by inhibiting intimal hyperplasia per se. Additional animal studies subsequently showed that, indeed, in the setting of pre-existing SMCs in the intimal lesion (ie, atherosclerotic plaque, fatty streaks), inhibiting SMC migration by way of beta(3) integrin blockade was an ineffective approach in the prevention of intimal hyperplasia and restenosis. However, given the wealth of basic and clinical information on the alpha(v)beta(3) integrin and its antagonists, we discuss in this article our new approach to this old solution by targeting a new clinical problem of early failure arteriovenous access for hemodialysis. Given the uniqueness of arteriovenous access in that there are essentially no significant atherosclerotic lesions in the artery and vein prior to the anastomosis, the seminal event of the migration of SMCs from the media to the neointima could by targeted once again with beta(3) integrin antagonists.

Topics: Animals; Blood Vessels; Cardiovascular Agents; Cell Proliferation; Constriction, Pathologic; Disease Models, Animal; Humans; Hyperplasia; Integrin alphaVbeta3; Protein Conformation; Tunica Intima; Vascular Patency; Vascular Surgical Procedures

Since its discovery, nitric oxide (NO) has emerged as a biologically important molecule and was even named Molecule of the Year by Science magazine in 1992. Specific to our interests, NO has been implicated in the regulation of vascular pathology. This review begins with a summary of the molecular biology of NO, from its discovery to the mechanisms of endogenous production. Next, we turn our attention to describing the arterial injury response of neointimal hyperplasia, and we review the role of NO in the pathophysiology of neointimal hyperplasia. Finally, we review the literature regarding NO-based therapies. This includes the development of inhalational-based NO therapies, systemically administered L-arginine and NO donors, NO synthase gene therapy, locally applied NO donors, and NO-releasing prosthetic materials. By reviewing the current literature, we emphasize the tremendous clinical potential that NO-based therapies can have on the development of neointimal hyperplasia.

Topics: Administration, Inhalation; Animals; Apoptosis; Arginine; Arteries; Blood Platelets; Cardiovascular Agents; Cell Proliferation; Chemotaxis, Leukocyte; Drug Carriers; Endothelial Cells; Extracellular Matrix; Genetic Therapy; Humans; Hyperplasia; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Nitric Oxide; Nitric Oxide Donors; Nitric Oxide Synthase; Platelet Adhesiveness; Platelet Aggregation; Tunica Intima

Percutaneous coronary intervention continues to revolutionize the treatment of coronary atherosclerosis. Restenosis remains a significant problem but may at last be yielding to technologic advances. The examination of neointimal hyperplasia in injured animal artery models has helped in our understanding of angioplasty and stenting mechanisms, and as drug-eluting stent (DES) technologies have arrived, they too have been advanced through the study of animal models. These models are useful for predicting adverse clinical outcomes in patients with DESs because suboptimal animal model studies typically lead to problematic human trials. Similarly, stent thrombosis in animal models suggests stent thrombogenicity in human patients. Equivocal animal model results at six or nine months occasionally have been mirrored by excellent clinical outcomes in patients. The causes of such disparities are unclear but may result from differing methods, including less injury severity than originally described in the models. Ongoing research into animal models will reconcile apparent differences with clinical trials and advance our understanding of how to apply animal models to clinical stenting in the era of DESs.

Topics: Animals; Cardiovascular Agents; Clinical Trials as Topic; Coronary Artery Disease; Coronary Restenosis; Coronary Thrombosis; Disease Models, Animal; Humans; Hyperplasia; Stents; Tunica Intima

To assess the vessel-healing pattern of Ultimaster drug-eluting stent using optical frequency domain imaging. Our hypothesis is that biodegradable polymer-based drug-eluting technology allows complete very early strut coverage.. The DISCOVERY 1TO3 study (Evaluation With OFDI of Strut Coverage of Terumo New Drug Eluting Stent With Biodegradable Polymer at 1, 2, and 3 Months) is a prospective, single-arm, multicenter study. A total of 60 patients with multivessel disease requiring staged procedure at 1 month were treated with Ultimaster. Optical frequency domain imaging was acquired at baseline, 1, 2, and 3 months. The primary end point is optical frequency domain imaging-assessed strut coverage at 3 months. Mean age of patients was 67.2±9.9 years, and 73.3% were male, and 36.7% presented with acute coronary syndrome. A total of 132 lesions were treated, with average 1.4 lesions per patient treated at baseline and 1.1 lesions treated at 1 month. Strut coverage at 3 months of single implanted stents (n=71, primary end point) was 95.2±5.2% and of combined single and overlapped stents was 95.4±4.9%. Strut coverage of combined single and overlapped stents at 1 (n=49) and 2 months (n=38) was 85.1±12.7% and 87.9±10.8%, respectively. The median neointimal hyperplasia thickness was 0.04, 0.05, and 0.06 mm, whereas mean neointimal hyperplasia obstruction was 4.5±2.4%, 5.2±3.4%, and 6.6±3.3% at 1, 2, and 3 months, respectively.. Nearly complete strut coverage was observed in this complex population very early after implantation of Ultimaster drug-eluting stent.. URL: https://www.clinicaltrials.gov. Unique identifier: NCT01844843.

Topics: Absorbable Implants; Aged; Cardiovascular Agents; Coronary Artery Disease; Coronary Vessels; Drug-Eluting Stents; Europe; Female; Humans; Hyperplasia; Male; Middle Aged; Neointima; Percutaneous Coronary Intervention; Polyesters; Predictive Value of Tests; Prospective Studies; Prosthesis Design; Risk Factors; Sirolimus; Time Factors; Tomography, Optical Coherence; Treatment Outcome; Wound Healing

The efficacy of DEB in modifying the high restenosis risk associated with BMS implantation is doubtful. Optical coherence tomography (OCT) may allow precise assessment of neointimal formation after stent implantation. We performed a single-center, prospective, 1:2 randomized trial comparing BMS implantation alone (BMS group) vs. additional DEB (DEB group). DEB patients were further randomized 1:1 to DEB before stenting (pre-DEB group), or after stenting (post-DEB group). Primary endpoint was OCT-assessed neointimal hyperplasia (expressed both as mean in-stent neointimal area and as percentage obstruction of the mean stent area) at 6 months. Secondary endpoints were the percentage of uncovered and malapposed stent struts. Thirty patients were enrolled and randomized to BMS (n = 10), pre-DEB (n = 10), post-DEB (n = 10). At 6-month OCT follow-up, DEB significantly reduced neointimal area compared with BMS: mean neointimal area 2.01 ± 0.89 vs. 3.03 ± 1.07 mm(2) (p = 0.02), percentage area obstruction 24.56 ± 12.50 vs. 37.51 ± 12.26 % (p = 0.02). The percentage of uncovered and malapposed stent struts did not differ significantly between BMS and DEB. In the comparison between pre-DEB and post-DEB, no significant difference was observed for both primary and secondary endpoints. In de novo coronary lesions treated with BMS, DEB use could be associated with a mild reduction in neointimal hyperplasia at 6 months; this effect could be unrelated to the timing of DEB dilation (pre- or post-stenting).. http://www.clinicaltrials.gov . Identifier: NCT01057563.

Topics: Aged; Angioplasty, Balloon, Coronary; Cardiac Catheters; Cardiovascular Agents; Coated Materials, Biocompatible; Coronary Angiography; Coronary Artery Disease; Coronary Restenosis; Female; Humans; Hyperplasia; Male; Metals; Middle Aged; Neointima; Percutaneous Coronary Intervention; Prospective Studies; Risk Factors; Rome; Stents; Time Factors; Tomography, Optical Coherence; Treatment Outcome

This study sought to report the late multimodality imaging and clinical outcomes of the novel poly-l-lactic-acid-based DESolve novolimus-eluting bioresorbable coronary scaffold for the treatment of de novo coronary lesions.. Bioresorbable scaffolds are an alternative to drug-eluting metallic stents and provide temporary vascular scaffolding, which potentially may allow vessel restoration and reduce the risk of future adverse events.. Overall, 126 patients were enrolled at 13 international sites between November 2011 and June 2012. The primary endpoint was in-scaffold late lumen loss at 6 months. Major adverse cardiac events, the main safety endpoint, were defined as the composite of cardiac death, target vessel myocardial infarction, or clinically indicated target lesion revascularization. All patients underwent angiography at 6 months. Serial intravascular ultrasound and optical coherence tomography were performed in a subset of patients.. The scaffold device success rate was 97% (n = 122 of 126), and procedural success was 100% (n = 122 of 122). The major adverse cardiac event rate was 3.3% (n = 4 of 122) at 6 months and 7.4% (n = 9 of 122) at 24 months, including 1 probable stent thrombosis within the first month. At 6-month angiographic follow-up, in-scaffold late lumen loss was 0.20 ± 0.32 mm. Paired intravascular ultrasound analysis demonstrated a significant increase in vessel, lumen and scaffold dimensions between post-procedure and 6-month follow-up, and strut-level optical coherence tomography analysis showed full strut coverage in 99 ± 1.7%.. Our results showed favorable performance of the DESolve scaffold, effective inhibition of neointimal hyperplasia, and for the first time, early luminal and scaffold growth at 6 months with sustained efficacy and safety through 2 years. (Elixir Medical Clinical Evaluation of the DESolve Novolimus Eluting Bioresorbable Coronary Scaffold System-The DESolve Nx Trial; NCT02086045).

Topics: Absorbable Implants; Aged; Brazil; Cardiovascular Agents; Coated Materials, Biocompatible; Coronary Angiography; Coronary Artery Disease; Coronary Vessels; Europe; Female; Humans; Hyperplasia; Macrolides; Male; Middle Aged; Neointima; New Zealand; Percutaneous Coronary Intervention; Predictive Value of Tests; Prospective Studies; Time Factors; Tomography, Optical Coherence; Treatment Outcome; Ultrasonography, Interventional

Persistence of stent polymer coating has been associated with incomplete endothelialization, expansive vessel remodeling, neoatherosclerosis, and delayed healing associated with inflammation that may contribute to late adverse events.. The BICARE (Lepu Medical, Beijing, China) stent is a novel polymer-free, nanotechnology-based stent eluting sirolimus and probucol. As a first in human feasibility study, patients with a single de novo native coronary stenosis <30 mm in length and with reference vessel diameter from 2.5 to 4.0 mm underwent revascularization with the BICARE stent. The primary endpoint of target lesion failure (TLF) was assessed at 30 days. Secondary endpoints included in-stent late lumen loss and proportion of uncovered or malapposed stent struts by optical coherence tomography at 4-month angiographic surveillance.. Among 32 consecutive patients (age, 55.7 ± 8.7 years; men, 62.5%; diabetes, 18.8%), the average baseline reference vessel diameter and lesion length were 2.85 ± 0.48 mm and 15.0 ± 5.6 mm, respectively. At 30 days there was no occurrence of TLF. At 4 months (angiographic follow-up, N=32), angiographic in-stent late loss was 0.14 ± 0.19 mm, and the in-stent binary restenosis rate was 3.1%. Complete strut coverage was 98.2% with 0.2% malapposition among 16,751 analyzed struts. At 18 months, TLF occurred in 3 (9.4%) patients related to repeat revascularization with no adverse safety events identified.. The preliminary feasibility and safety of a polymer-free, dual-drug eluting stent are demonstrated by absence of early adverse safety events and favorable angiographic suppression of neointimal hyperplasia. Stent imaging suggests favorable healing with extensive stent strut coverage and very low malapposition. These findings further inform comparison with biopermanent polymer DES.

Topics: Cardiovascular Agents; China; Coronary Angiography; Coronary Restenosis; Coronary Stenosis; Drug Combinations; Drug-Eluting Stents; Feasibility Studies; Female; Humans; Hyperplasia; Male; Middle Aged; Neointima; Percutaneous Coronary Intervention; Probucol; Prosthesis Design; Sirolimus; Time Factors; Tomography, Optical Coherence; Treatment Outcome

To evaluate the effects of the everolimus-eluting Xience™/Promus™ stent (EES) and the sirolimus-eluting Cypher™ stent (SES) on intimal hyperplasia (IH) in diabetic patients.. Patients with diabetes mellitus have increased risk of in-stent restenosis after coronary stent implantation due to intimal hyperplasia (IH).. In a sub study of the Randomized Comparison of Everolimus-Eluting and Sirolimus-Eluting Stents in Patients Treated with Percutaneous Coronary Intervention (SORT OUT IV trial), serial intravascular ultrasound (IVUS) 10-month follow-up data were available in 88 patients, including 48 EES and 40 SES treated patients. IVUS endpoints included IH volume, in-stent % volume obstruction and changes in external elastic membrane (EEM) volume.. Compared with the SES group, IH volume was increased in the EES group [median (interquartile range): 2.8 mm(3) (0.0-12.6) vs. 0.0 mm(3) (0.0-1.1), P = 0.001]. In-stent % volume obstruction was increased in EES compared to SES [median (interquartile range): 1.6% (0.0-8.2) vs. 0.0% (0.0-1.0), P = 0.001]. Peri-stent external elastic membrane (EEM) volume: (post procedure vs. follow-up EES [300 mm(3) (219-491) vs. 307 mm(3) (223-482), P = 0.73] and SES [316 mm(3) (235-399) vs. 323 mm(3) (246-404), P = 0.05]) and peri-stent plaque volume: EES [163 mm(3) (103-273) vs. 184 mm(3) (115-291), P = 0.18] and SES [186 mm(3) (139-248) vs. 175 mm(3) (153-243), P = 0.26]) were unchanged in both groups. In the proximal reference segment a significant increase in plaque area was seen in the EES group only, without vascular remodeling.. In diabetic patients, EES stent implantation was associated with increased IH volume obstruction without involvement of vascular remodeling.

Topics: Aged; Cardiovascular Agents; Coronary Artery Disease; Coronary Restenosis; Coronary Vessels; Diabetic Angiopathies; Drug-Eluting Stents; Everolimus; Female; Humans; Hyperplasia; Male; Middle Aged; Neointima; Percutaneous Coronary Intervention; Predictive Value of Tests; Prosthesis Design; Sirolimus; Time Factors; Treatment Outcome; Ultrasonography, Interventional; Vascular Remodeling

This study was designed to compare neointimal hyperplasia and peri-stent arterial remodeling after implantation of everolimus-eluting stent (EES) versus sirolimus-eluting stent (SES) using intravascular ultrasound (IVUS). The study population was a subgroup of 278 patients from the EXCELLENT trial, a randomized study comparing EES to SES in de novo coronary artery lesions (total n = 1,443, 3:1 randomization) who underwent post-PCI and 9-month follow-up IVUS evaluation. There were 209 patients in the EES group and 69 in the SES group. Baseline clinical and angiographic characteristics were similar between the two groups except for age and target lesion locations. At 9 months, percent neointimal volume obstruction did not differ between EES and SES (2.6 ± 4.0 % vs. 2.5 ± 4.8 %, p = 0.814). However, the relative change in the vessel (4.3 ± 13.7 % vs. 8.8 ± 18.6 %, p = 0.030) and plaque volume index (4.2 ± 17.4 % vs. 10.5 ± 22.3 %, p = 0.016) of the stented segment from post-intervention to follow-up was significantly less with EES than with SES. In addition, positive peri-stent vascular remodeling defined as an increase in vessel volume index >10 % (27.8 vs. 42.0 %, p = 0.027) and late acquired stent malapposition (LASM, 1.9 vs. 15.9 %, p < 0.001) were observed less frequently with EES than SES. EES and SES were similarly effective in reducing neointimal hyperplasia. However, positive peri-stent vascular remodeling and LASM occurred less frequently with EES than SES.

Topics: Aged; Cardiovascular Agents; Chi-Square Distribution; Coronary Angiography; Coronary Artery Disease; Coronary Vessels; Drug-Eluting Stents; Everolimus; Female; Humans; Hyperplasia; Logistic Models; Male; Middle Aged; Multivariate Analysis; Neointima; Odds Ratio; Percutaneous Coronary Intervention; Predictive Value of Tests; Prosthesis Design; Republic of Korea; Risk Factors; Sirolimus; Time Factors; Treatment Outcome; Ultrasonography, Interventional

Restenosis after percutaneous transluminal angioplasty (PTA) of the superficial femoral artery (SFA) may occur in 45% of patients at 2 years follow-up. Paclitaxel-coated balloons have been found to reduce neointimal hyperplasia, and thus reduce restenosis. Recently, the Legflow(®) paclitaxel-coated balloon (Cardionovum Sp.z.o.o., Warsaw, Poland) (LPEB) has been introduced. This balloon is covered with shellac, a Food and Drug Administration (FDA) approved natural resin, to obtain an equally distributed tissue concentration of paclitaxel. The RAPID trial is designed to assess restenosis after PTA using the Legflow balloon combined with nitinol stenting versus uncoated balloons with nitinol stenting in SFA lesions >5 cm.. A total of 176 adult patients with Rutherford class 2 to class 6 symptoms due to intermediate (5-15 cm) or long (>15 cm) atherosclerotic lesions in the SFA will be randomly allocated for treatment with LPEB with nitinol stenting or uncoated balloon angioplasty with stenting. Stenting will be performed using the Supera(®) stent in both groups (IDEV Technologies Inc., Webster, TX). The primary endpoint is the absence of binary restenosis of the treated SFA segment. Secondary outcomes are target lesion revascularization (TLR), clinical and hemodynamic outcome, amputation rate, mortality rate, adverse events, and device-specific adverse events. Follow up consists of four visits in which ankle-brachial indices (ABI), toe pressure measurements, and duplex ultrasound (DUS) will be performed. Furthermore, a peripheral artery questionnaire (PAQ) will be completed by the patients at each follow-up. In the event that DUS reveals a symptomatic >50% restenosis, or a >75% asymptomatic restenosis, additional digital subtraction angiography will be performed with any necessary re-intervention.. The RAPID trial is a multicenter randomized controlled patient blind trial that will provide evidence concerning whether the use of the Legflow paclitaxel/shellac coated balloons with nitinol stenting significantly reduces the frequency of restenosis in intermediate and long SFA lesions compared to standard PTA and stenting.. ISRCTN47846578.

Topics: Alloys; Amputation, Surgical; Angiography, Digital Subtraction; Angioplasty, Balloon; Ankle Brachial Index; Arterial Occlusive Diseases; Cardiovascular Agents; Clinical Protocols; Coated Materials, Biocompatible; Constriction, Pathologic; Equipment Design; Equipment Failure; Femoral Artery; Hemodynamics; Humans; Hyperplasia; Limb Salvage; Neointima; Netherlands; Paclitaxel; Predictive Value of Tests; Prosthesis Design; Prosthesis Failure; Recurrence; Research Design; Resins, Plant; Single-Blind Method; Stents; Surveys and Questionnaires; Time Factors; Treatment Outcome; Ultrasonography, Doppler, Duplex; Vascular Access Devices

Everolimus-eluting stents (EES) have shown favorable clinical outcomes. However, there have been no studies evaluating early vascular response after EES implantation. We designed a prospective study to compare the neointimal response between zotarolimus-eluting stents (ZES) and EES at 3 and 12 months using serial optical coherence tomography examinations.. Sixty patients who underwent 3-month and 12-month follow-up optical coherence tomography (36 EES, 24 ZES) were included. Neointimal coverage and malapposition were evaluated using a strut-based analysis at both 3 and 12 months. Neointimal hyperplasia area and thrombus were assessed. ZES showed a higher incidence of covered struts (81.5 vs. 77.1%, P<0.0001) and lower incidence of malapposed struts (1.4 vs. 2.3%, P=0.001) than EES at 3 months. However, at 12 months, EES showed a slightly higher incidence of covered struts (96.4 vs. 93.6%, P<0.0001) and a lower incidence of malapposed struts (0.9 vs. 1.1%, P=0.03) than ZES. Neointimal hyperplasia area was greater in the ZES group than in the EES group at both 3 and 12 months (0.77 vs. 0.49 mm, P=0.03 and 1.50 vs. 0.97 mm, P=0.01, respectively). No significant difference in the incidence of thrombus was observed at both 3 and 12 months.. ZES showed rapid neointimal healing compared with EES at 3 months. However, at 12 months, EES had a slightly better vascular healing profile than ZES.

Topics: Aged; Cardiovascular Agents; Chi-Square Distribution; Coronary Angiography; Coronary Artery Disease; Coronary Vessels; Drug-Eluting Stents; Everolimus; Female; Humans; Hyperplasia; Male; Middle Aged; Neointima; Observer Variation; Odds Ratio; Percutaneous Coronary Intervention; Predictive Value of Tests; Prospective Studies; Prosthesis Design; Reproducibility of Results; Republic of Korea; Sirolimus; Time Factors; Tomography, Optical Coherence; Treatment Outcome; Wound Healing

Incomplete stent endothelialization is associated with late and very late stent thrombosis. In a post hoc analysis of the BASE-ACS trial, we sought to assess neointimal coverage and coronary flow reserve (CFR) 9 months after implantation of titanium-nitride-oxide-coated bioactive stents (BAS) versus everolimus-eluting stents (EES) in patients with acute coronary syndrome (ACS). In the BASE-ACS trial, 827 patients with ACS were randomized to receive either BAS or EES. In the current study, we examined neointimal growth and strut coverage by optical coherence tomography and CFR by trans-thoracic echocardiography in 28 consecutive non-diabetic patients with the culprit lesion in the left anterior descending coronary artery. The primary endpoints were binary stent strut coverage and CFR at 9-month follow-up. A total of 13 patients were included in the BAS group (2,033 struts); 15 in the EES group (2,898 struts). Binary stent strut coverage was higher and malapposed struts lower with BAS versus EES (99.4 vs 89.2, and 0.2 vs 4.6%, respectively, p < 0.001 for both). Neointimal hyperplasia thickness was greater with BAS versus EES (274.2 vs 100.1 μm, respectively, p < 0.001). CFR was lower with EES versus BAS (2.2 ± 0.8 vs. 3.0 ± 0.5, respectively, p = 0.001). Abnormal CFR (<2.5) were detected in 10 patients in the EES group versus one in the BAS group (p = 0.002). The current study demonstrated that in patients with ACS, BAS resulted in improved neointimal stent strut coverage and better coronary vasodilator function as compared with EES at 9-month follow-up.

Topics: Acute Coronary Syndrome; Cardiovascular Agents; Coated Materials, Biocompatible; Coronary Circulation; Coronary Vessels; Drug-Eluting Stents; Echocardiography, Doppler, Color; Echocardiography, Doppler, Pulsed; Everolimus; Humans; Hyperplasia; Neointima; Percutaneous Coronary Intervention; Predictive Value of Tests; Prospective Studies; Prosthesis Design; Single-Blind Method; Sirolimus; Stents; Time Factors; Titanium; Tomography, Optical Coherence; Treatment Outcome; Vasodilation

Drug-eluting stents (DES) have reduced the rate of restenosis but recent studies have raised concern over the risk of late stent thrombosis (LST). Incomplete stent endothelialization and delayed vascular healing have been associated with LST. The titanium-nitride-oxide coated bio-active stent (BAS) has shown promising results in patients with acute coronary syndromes, but there is little long-term optical coherence tomography (OCT) data comparing BAS with DES. The TITAX-AMI trial is a prospective, randomized, multicenter trial comparing BAS to paclitaxel-eluting stent (PES) in 425 patients with acute myocardial infarction. A total of 18 patients (9 per group) with no major cardiac events during follow-up, were enrolled in this substudy >36 months (mean 47 months) after stent implantation. Quantitative coronary angiography was performed and stent strut endothelialization and vascular healing were assessed with OCT. The binary stent strut coverage was significantly higher in the BAS group compared with the PES group (99.6 vs. 89.2%, p < 0.001) and there were less malapposed struts in the BAS group (0.2 vs. 13.8%, respectively, p < 0.001). The neointimal hyperplasia (NIH) thickness (266 ± 166 vs. 126 μm ± 126 μm, p < 0.001) and percentage of NIH area (26.2 vs. 7.6%, p < 0.001) were greater in the BAS group than in the PES group. Late incomplete endothelialization was not uncommon after PES implantation. Stents in the BAS group were completely endothelialized. This difference may contribute to the more common LST after PES implantation in the TITAX-AMI trial.

Topics: Aged; Cardiovascular Agents; Chi-Square Distribution; Coated Materials, Biocompatible; Coronary Angiography; Coronary Restenosis; Coronary Thrombosis; Coronary Vessels; Drug-Eluting Stents; Endothelial Cells; Female; Humans; Hyperplasia; Male; Middle Aged; Myocardial Infarction; Neointima; Paclitaxel; Percutaneous Coronary Intervention; Predictive Value of Tests; Prospective Studies; Prosthesis Design; Stents; Time Factors; Titanium; Tomography, Optical Coherence; Treatment Outcome

Neointimal hyperplasia plays a pivotal role in the pathogenesis of in-stent restenosis in patients undergoing percutaneous coronary interventions. Drug-eluting balloons are a promising tool to prevent restenosis after coronary angioplasty. Moreover, an increased knowledge of the pathophysiology of restenosis my help improve therapeutic strategies.. We present the design of an open-label, randomized three-arm clinical trial aimed to assess whether a strategy of bare-metal stent implantation with additional use of drug-eluting balloons, either before (pre-dilation) or after stenting (post-dilation), reduces the primary endpoint of in-stent neointimal hyperplasia area as compared with a strategy of bare-metal stent implantation alone. This primary endpoint will be assessed by optical coherence tomography at follow-up. Secondary endpoints will be the percentage of uncovered struts, and the percentage of struts with incomplete apposition. An ancillary study investigating the relation between systemic levels of endothelial progenitors cells and neointimal hyperplasia, and the interaction between endothelial progenitors cell levels and drug-eluting balloons has been planned. Thirty consecutive patients undergoing percutaneous coronary intervention will be randomized with a 1:1:1 design to bare-metal stent implantation alone (n = 10); bare-metal stent implantation after pre-dilation with a drug-eluting balloon (n = 10); or bare-metal stent implantation followed by post-dilation with a drug-eluting balloon (n = 10). Six-month follow-up coronary angiography with optical coherence tomography imaging of the stented segment will be performed in all patients. Blood samples for the assessment of endothelial progenitors cell levels will be collected on admission and at 6 months.. Experimental and early clinical data showed that inhibition of neointimal hyperplasia may be obtained by local administration of antiproliferative drugs loaded on the surface of angioplasty balloons. The INtimal hyPerplasia evAluated by oCT in de novo COROnary lesions treated by drug-eluting balloon and bare-metal stent (IN-PACT CORO) trial was conceived to test the superiority of a strategy of bare-metal stent implantation with additional drug-eluting balloon use (either before or after stenting) versus a strategy of bare-metal stent implantation alone for the reduction of neointimal hyperplasia. We also planned an ancillary study to assess the role of endothelial progenitors cells in the pathophysiology of neointimal hyperplasia.. Clinicaltrials.gov NCT01057563.

Topics: Angioplasty, Balloon, Coronary; Cardiovascular Agents; Catheters; Coated Materials, Biocompatible; Coronary Angiography; Coronary Artery Disease; Coronary Restenosis; Coronary Vessels; Endothelial Cells; Equipment Design; Humans; Hyperplasia; Italy; Metals; Neointima; Paclitaxel; Predictive Value of Tests; Prosthesis Design; Research Design; Stem Cells; Stents; Time Factors; Tomography, Optical Coherence; Treatment Outcome

The purpose of this study was to investigate the vascular response of the everolimus-eluting stent (EES) compared with the paclitaxel-eluting stent (PES) using serial intravascular ultrasound (IVUS).. Data were obtained from the SPIRIT III trial, a multicentre, 2:1 randomised, controlled study comparing EES and PES in de novo native coronary artery lesions. IVUS images were eligible for volumetric analysis at eight-month follow-up in 158 lesions (EES: 113, PES: 45). At eight months, EES had a smaller neointimal volume index (VI: mm3/mm) (EES: 0.4±0.4 vs. PES: 0.8±0.8 mm3/mm, p=0.002) and also a smaller % neointimal obstruction (EES: 7.1±6.7% vs. PES: 11.1±10.5%, p=0.005) compared with PES. While there was no significant change in vessel VI with EES, there was a significant increase in vessel VI in PES during eight-month follow-up (EES: 0.1±1.2 vs. PES: 1.2±0.8 mm3/mm, p=0.001). There were no statistical differences in the frequency of edge dissection or incomplete stent apposition between the two groups.. Detailed IVUS analysis confirmed significantly less neointimal hyperplasia with EES compared with PES. While there was no increase in vessel volume with EES during the eight-month follow-up period, vessel enlargement was seen at the stented segment in PES.

Topics: Aged; Cardiovascular Agents; Chi-Square Distribution; Coronary Artery Disease; Coronary Restenosis; Coronary Vessels; Drug-Eluting Stents; Everolimus; Female; Humans; Hyperplasia; Japan; Male; Middle Aged; Neointima; Paclitaxel; Percutaneous Coronary Intervention; Predictive Value of Tests; Prospective Studies; Prosthesis Design; Registries; Sirolimus; Time Factors; Treatment Outcome; Ultrasonography, Interventional; United States

We designed a randomized trial exploiting optical coherence tomography (OCT) to assess coverage and apposition of overlapping bare-metal stents (BMS) and drug-eluting stents (DES) in human coronary arteries.. Overlapping DES impair healing in animals. Optical coherence tomography allows accurate in vivo assessment of stent strut coverage and apposition.. Seventy-seven patients with long coronary stenoses were randomized to overlapping sirolimus-eluting stents (SES), paclitaxel-eluting stents (PES), zotarolimus-eluting stents (ZES), or BMS. The primary goal of the study was to determine the rate of uncovered/malapposed struts in overlap versus nonoverlap segments, according to stent type, at 6-month follow-up with OCT.. A total of 53,047 struts were analyzed. The rate of uncovered/malapposed struts was 1.5 +/- 3.4% and 0.6 +/- 2.7% in overlap versus nonoverlap BMS (p = NS), respectively, and 4.3 +/- 11% and 3.6 +/- 8% in overlap versus nonoverlap DES (p = NS), respectively. There were no differences in the rates of uncovered/malapposed struts between overlapping BMS and DES, likely due to low frequency of uncovered/malapposed struts in ZES (0.1 +/- 0.4%), which offset the higher rates observed in SES (6.7 +/- 9.6%) and PES (6.7 +/- 16.5%, p < 0.05). Overlap segments showed greater neointimal volume obstruction versus nonoverlap segments in all DES (p < 0.05 for all DES types). Strut-level neointimal thickness at overlap and nonoverlap segments were lowest in SES (0.16 +/- 0.1 mm and 0.12 +/- 0.1 mm, respectively) compared with PES (0.27 +/- 0.1 mm and 0.20 +/- 0.1 mm, respectively), ZES (0.40 +/- 0.16 mm and 0.33 +/- 0.13 mm, respectively), and BMS (0.55 +/- 0.31 mm and 0.53 +/- 0.25 mm, respectively, p < 0.05).. As assessed by OCT the impact of DES on vascular healing was similar at overlapping and nonoverlapping sites. However, strut malapposition, coverage pattern, and neointimal hyperplasia differ significantly according to DES type. (Optical Coherence Tomography for Drug Eluting Stent Safety [ODESSA]; NCT00693030).

Topics: Aged; Aged, 80 and over; Angioplasty, Balloon, Coronary; Cardiovascular Agents; Coronary Angiography; Coronary Stenosis; Coronary Vessels; Drug-Eluting Stents; Feasibility Studies; Female; Humans; Hyperplasia; Male; Metals; Middle Aged; Paclitaxel; Predictive Value of Tests; Prospective Studies; Prosthesis Design; Sirolimus; Stents; Time Factors; Tomography, Optical Coherence; Treatment Outcome; Ultrasonography, Interventional

Erythropoietin (EPO) enhances re-endothelialization and anti-apoptotic action. Larger clinical studies to examine the effects of high-dose EPO are in progress in patients with acute myocardial infarction (AMI).. The aim of this multi-center pilot study was to investigate the effect of `low-dose EPO' (6,000 IU during percutaneous coronary intervention (PCI), 24 h and 48 h) in 35 patients with a first ST-elevated AMI undergoing PCI who was randomly assigned to EPO or placebo (saline) treatment. Neointimal volume, cardiac function and infarct size were examined in the acute phase and 6 months later (ClinicalTrials.gov identifier: NCT00423020). No significant regression in in-stent neointimal volume was observed, whereas left ventricular (LV) ejection fraction was significantly improved (49.2% to 55.7%, P=0.003) and LV end-systolic volume was decreased in the EPO group (47.7 ml to 39.0 ml, P=0.036). LV end-diastolic volume tended to be reduced from 90.2% to 84.5% (P=0.159), whereas in the control group it was inversely increased (91.7% to 93.7%, P=0.385). Infarction sizes were significantly reduced by 38.5% (P=0.003) but not in the control group (23.7%, P=0.051). Hemoglobin, peak creatine kinase values, and CD34(+)/CD133(+)/CD45(dim) endothelial progenitors showed no significant changes. No adverse events were observed during study periods.. This is a first study demonstrating that short-term `low-dose' EPO to PCI-treated AMI patients did not prevent neointimal hyperplasia but rather improved cardiac function and infarct size without any clinical adverse effects.

Topics: Aged; Angioplasty, Balloon, Coronary; Biomarkers; Cardiovascular Agents; Chi-Square Distribution; Coronary Angiography; Coronary Restenosis; Creatine Kinase; Endothelial Cells; Erythropoietin; Female; Hemoglobins; Humans; Hyperplasia; Japan; Male; Middle Aged; Myocardial Infarction; Myocardium; Pilot Projects; Placebo Effect; Prospective Studies; Recombinant Proteins; Stem Cells; Stroke Volume; Time Factors; Treatment Outcome; Ultrasonography, Interventional; Ventricular Function, Left; Ventricular Remodeling

To investigate the mechanistic basis underlying antirestenosis and the antiatherogenic effect of pioglitazone in patients with type 2 diabetes mellitus who were undergoing zotarolimus-eluting stent implantation.. Recent studies highlight the beneficial effect of pioglitazone in attenuating neointimal growth after stent implantation. Patients with coronary artery diseases were randomly assigned to pioglitazone (n=47) or placebo (n=47) after stent implantation. Pioglitazone significantly reduced neointimal hyperplasia within the stented lesion and attenuated total plaque burden in the in-segment regions of the stent, as assessed by intravascular ultrasonography at the 8-month follow-up. These changes were preceded by reduced circulating natural killer (NK) cells, diminished interleukin 6 and monocyte chemoattractant protein-1 levels, and downregulation of chemokine receptor 2 at 2 days after stent implantation; and an elevated interleukin 10 level at 10 days after implantation. Furthermore, the proliferation and migration of vascular smooth muscle cells were inhibited in the presence of pioglitazone-treated patient serum, demonstrating that the antiproliferative effects of pioglitazone occurred concurrently with its antiinflammatory action.. Our data present early cellular and immunologic changes by pioglitazone that might have been associated with antirestenotic and antiatherogenic effects in diabetic patients. Inhibiting proinflammatory responses while promoting antiinflammatory circuits, together with an antiproliferative action, may, in part, account for the antirestenotic effect of pioglitazone by altering vascular remodeling processes in the early phase.

Topics: Adult; Aged; Angioplasty, Balloon, Coronary; Biomarkers; Blood Glucose; Cardiovascular Agents; Cell Movement; Cell Proliferation; Cells, Cultured; Chemokine CCL2; Coronary Angiography; Coronary Artery Disease; Coronary Restenosis; Coronary Vessels; Diabetes Mellitus, Type 2; Dose-Response Relationship, Drug; Drug-Eluting Stents; Female; Glycated Hemoglobin; Humans; Hyperplasia; Hypoglycemic Agents; Inflammation Mediators; Insulin; Interleukin-6; Killer Cells, Natural; Lipids; Male; Middle Aged; Myocytes, Smooth Muscle; Pioglitazone; Prospective Studies; Prosthesis Design; Receptors, CCR2; Republic of Korea; Single-Blind Method; Sirolimus; Thiazolidinediones; Time Factors; Treatment Outcome; Tunica Intima; Ultrasonography, Interventional

We tested two novel drug-eluting stents (DES), covered with a biodegradable-polymer carrier and releasing paclitaxel or sirolimus, which were compared against a bare metal stent (primary objective). The DES differed by the drug, but were identical otherwise, allowing to compare the anti-restenosis effects of sirolimus versus paclitaxel (secondary objective).. The efficacy of novel DES with biodegradable polymers should be tested in the context of randomized trials, even when using drugs known to be effective, such as sirolimus and paclitaxel.. Overall, 274 patients with de novo coronary lesions in native vessels scheduled for stent implantation were randomly assigned (2:2:1 ratio) for the paclitaxel (n = 111), sirolimus (n = 106), or bare metal stent (n = 57) groups. Angiographic follow-up was obtained at 9 months and major cardiac adverse events up to 12 months.. Both paclitaxel and sirolimus stents reduced the 9-month in-stent late loss (0.54-0.44 mm, 0.32-0.43 mm, vs. 0.90-0.45 mm respectively), and 1-year risk of target vessel revascularization and combined major adverse cardiac events (P < 0.05 for both, in all comparisons), compared with controls. Sirolimus stents had lower late loss than paclitaxel stents (P < 0.01), but similar 1-year clinical outcomes. There were no differences in the risk of death, infarction, or stent thrombosis among the study groups.. Both novel DES were effective in reducing neointimal hyperplasia and 1-year re-intervention, compared to bare metal stents. Our findings also suggest that sirolimus is more effective than paclitaxel in reducing angiographic neointima, although this effect was not associated with better clinical outcomes.

Topics: Aged; Angioplasty, Balloon, Coronary; Brazil; Cardiovascular Agents; Cardiovascular Diseases; Coated Materials, Biocompatible; Coronary Angiography; Coronary Restenosis; Coronary Stenosis; Drug-Eluting Stents; Female; Humans; Hyperplasia; Kaplan-Meier Estimate; Male; Metals; Middle Aged; Myocardial Infarction; Paclitaxel; Proportional Hazards Models; Prosthesis Design; Risk Assessment; Sirolimus; Stents; Thrombosis; Time Factors; Treatment Outcome

The aim of this study was to compare the vessel response between zotarolimus-eluting stents (ZES) and paclitaxel-eluting stents (PES) using intravascular ultrasound.. The ENDEAVOR IV (Randomized Comparison of Zotarolimus- and Paclitaxel-Eluting Stents in Patients With Coronary Artery Disease) trial was a randomized controlled study of zotarolimus-eluting, phosphorylcholine-coated, cobalt-alloy stents for the treatment of de novo coronary lesions compared with using PES for the same treatment.. Data were obtained from patients with serial (baseline and 8-months follow-up) intravascular ultrasound analysis available (n = 198). Volumetric analysis was performed for vessel, lumen, plaque, stent, and neointima. Cross-sectional narrowing (given as percentage) was defined as neointimal area divided by stent area. Neointima-free frame ratio was calculated as the number of frames without intravascular ultrasound-detectable neointima divided by the total number of frames within the stent. Subsegment analysis was performed at every matched 1-mm subsegment throughout the stent.. At follow-up, the ZES group showed significantly greater percentage of neointimal obstruction (16.6 +/- 12.0% vs. 9.9 +/- 8.9%, p < 0.01) and maximum cross-sectional narrowing (31.8 +/- 16.1% vs. 25.2 +/- 14.9%, p < 0.01) with smaller minimum lumen area than the PES group did. However, the incidence of maximum cross-sectional narrowing >50% was similar in the 2 groups. Neointima-free frame ratio was significantly lower in the ZES group. In overall analysis, whereas the PES group showed positive remodeling during follow-up (13.7 +/- 4.2 mm(3)/mm to 14.3 +/- 4.3 mm(3)/mm), the ZES group showed no significant difference (12.7 +/- 3.6 mm(3)/mm to 12.9 +/- 3.5 mm(3)/mm). In subsegment analysis, significant focal positive vessel remodeling was observed in 5% of ZES and 25% of PES cases (p < 0.05).. There were different global and focal vessel responses for ZES and PES. Both drug-eluting stents showed a similar incidence of lesions with severe narrowing despite ZES having a moderate increase in neointimal hyperplasia compared with neointimal hyperplasia in PES. There was a relatively lower neointima-free frame ratio in ZES, suggesting a greater extent of neointimal coverage. (The ENDEAVOR IV Clinical Trial: A Trial of a Coronary Stent System in Coronary Artery Lesions; NCT00217269).

Topics: Aged; Alloys; Angioplasty, Balloon, Coronary; Cardiovascular Agents; Coated Materials, Biocompatible; Cobalt; Coronary Artery Disease; Coronary Restenosis; Drug-Eluting Stents; Female; Humans; Hyperplasia; Male; Middle Aged; Paclitaxel; Phosphorylcholine; Prosthesis Design; Single-Blind Method; Sirolimus; Time Factors; Treatment Outcome; Tunica Intima; Ultrasonography, Interventional; United States

The RESOLUTE trial examined the safety and efficacy of a next-generation zotarolimus-eluting coronary stent, Resolute (Medtronic CardioVascular Inc., Santa Rosa, California).. Revascularization benefits associated with current drug-eluting stents are often diminished in the presence of complex coronary lesions and in certain patient cohorts. Resolute uses a new proprietary polymer coating that extends the duration of drug delivery to match the longer healing duration often experienced in more complex cases.. The RESOLUTE trial was a prospective, nonrandomized, multicenter study of the Resolute stent in 139 patients with de novo coronary lesions with reference vessel diameters > or =2.5 and < or =3.5 mm and lesion length > or =14 and < or =27 mm. The primary end point was 9-month in-stent late lumen loss by quantitative coronary angiography. Secondary end points included major adverse cardiac events (MACE) at 30 days, 6, 9, and 12 months; acute device, lesion, and procedure success; and 9-month target vessel failure (TVF), target lesion revascularization (TLR), stent thrombosis, neointimal hyperplastic (NIH) volume, and percent NIH volume obstruction.. The 9-month in-stent late lumen loss was 0.22 +/- 0.27 mm. Cumulative MACE were 4.3%, 4.3%, 7.2%, and 8.7% at 30 days, 6, 9, and 12 months, respectively. Acute lesion, procedure, and device success rates were 100.0%, 95.7%, and 99.3%, respectively. At 9 months, TLR was 0.0%, TVF was 6.5%, stent thrombosis was 0.0%, NIH volume was 6.55 +/- 7.83 mm(3), and percent NIH volume obstruction was 3.73 +/- 4.05%.. In this feasibility study, the Resolute stent demonstrated low in-stent late lumen loss, minimal neointimal hyperplastic ingrowth, low TLR, no stent thrombosis, and acceptable TVF and MACE. (The RESOLUTE Clinical Trial; NCT00248079).

Topics: Aged; Angioplasty, Balloon, Coronary; Australia; Cardiovascular Agents; Coronary Angiography; Coronary Restenosis; Coronary Stenosis; Drug-Eluting Stents; Feasibility Studies; Female; Humans; Hyperplasia; Kaplan-Meier Estimate; Male; Middle Aged; Myocardial Infarction; New Zealand; Prospective Studies; Prosthesis Design; Sirolimus; Thrombosis; Time Factors; Treatment Outcome; Ultrasonography, Interventional; United States

The aim of this study was to determine the safety and efficacy of a novel pimecrolimus-eluting stent in a porcine coronary model and in a phase I clinical trial.. Rapamycin- and paclitaxel-eluting stents reduce the need for repeat intervention by limiting neointimal hyperplasia but might cause delayed healing, pre-disposing patients to late stent thrombosis. Because inflammation plays a key role in restenosis, pimecrolimus, an anti-inflammatory drug, might reduce restenosis without adversely affecting re-endothelialization.. We evaluated a novel polymeric pimecrolimus-eluting stent covered with a thin parylene C diffusion barrier in a porcine coronary model and in a phase I human clinical trial. The clinical study was a prospective, nonrandomized, first-in-human hypothesis-generating study that enrolled 15 patients who had a single de novo native coronary stenosis.. At 28 days and 3 months in the porcine model, histopathologic indicators predicted safety and biocompatibility when stents coated with polymer only, drug only, and 2 drug-polymer formulations were compared with bare-metal stents (BMS). In the phase I clinical trial, 15 patients had successful implantation of pimecrolimus-eluting stents. By 6 months, no patient suffered death, myocardial infarction, or stent thrombosis. However, the angiographic restenosis (61%), mean late loss (1.44 mm), and repeat target lesion revascularization (53%) were significantly higher than historical BMS controls. Whereas the primary end point was percent volume obstruction, restenosis was so severe that operators performed intravascular ultrasound examination in only 6 patients.. Pimecrolimus-eluting stents induced an exaggerated neointimal hyperplasia at 6 months in comparison with historical controls.

Topics: Adult; Aged; Angioplasty, Balloon, Coronary; Animals; Cardiovascular Agents; Coated Materials, Biocompatible; Coronary Angiography; Coronary Restenosis; Coronary Stenosis; Disease Models, Animal; Drug-Eluting Stents; Feasibility Studies; Female; Humans; Hyperplasia; Male; Middle Aged; New Zealand; Polymers; Prospective Studies; Prosthesis Design; Registries; Risk Assessment; Severity of Illness Index; Swine; Tacrolimus; Time Factors; Treatment Outcome; Ultrasonography, Interventional; Xylenes

The newly developed Nobori coronary stent coated with a bioresorbable polymer, polylactic acid, and the antiproliferative agent Biolimus A9 has the potential to reduce restenosis by suppressing neointima formation.. We conducted a randomized (2:1), controlled trial comparing the Biolimus A9-eluting stent Nobori and the paclitaxel-eluting stent Taxus Liberté, in 243 patients (153 Nobori and 90 Taxus) at 29 centers in Europe, Asia, and Australia. Patients with previously untreated lesions in up to 2 native coronary arteries were considered for enrollment. The primary end point was in-stent late loss at 9 months, whereas secondary end points included other quantitative coronary angiography parameters, such as in-segment late loss and the rate of restenosis as well as key intravascular ultrasound parameters. Clinical secondary end points were stent thrombosis and composite of major adverse cardiac events comprising death, myocardial infarction, and target vessel revascularization. At 9 months, the in-stent late loss was significantly lower in the Nobori group compared with the Taxus group (0.11+/-0.30 mm versus 0.32+/-0.50 mm) reaching both the primary hypothesis of noninferiority of Nobori stent versus Taxus Liberté stent (P<0.001) and the secondary hypothesis of superiority (P=0.001). This finding was confirmed by a significant reduction in binary restenosis from 6.2% in Taxus to 0.7% in Nobori (P=0.02) and neointimal volume obstruction, detected by intravascular ultrasound, from 5.5+/-7.2% in Taxus to 1.8+/-5.2% in Nobori (P=0.01). The major adverse cardiac events rate was 4.6% in the Nobori and 5.6% in the Taxus cohort of patients. The stent thrombosis rate was 0% in the Nobori arm and 4.4% in the Taxus arm.. The NOBORI 1 clinical trial confirmed its primary hypothesis--noninferiority of the Nobori Biolimus A9-eluting stent versus the Taxus Liberté stent in reducing neointimal proliferation. Both stents showed a low major adverse cardiac events rate in the studied population.

Topics: Angioplasty, Balloon, Coronary; Asia; Australia; Cardiovascular Agents; Cell Proliferation; Coronary Angiography; Coronary Restenosis; Coronary Stenosis; Coronary Vessels; Drug-Eluting Stents; Europe; Female; Humans; Hyperplasia; Male; Middle Aged; Myocardial Infarction; Paclitaxel; Prospective Studies; Risk Assessment; Sirolimus; Thrombosis; Time Factors; Treatment Outcome; Ultrasonography, Interventional

To evaluate effects of sirolimus-eluting stents (SES) compared to bare-metal stents (BMS) at stent edges in patients with acute myocardial infarction (AMI).. Clinical, angiographic, intravascular ultrasound (lVUS) and virtual histology (VH)-IVUS results were obtained and analysed in 20 SES and 20 BMS AMI patients at the index procedure and at nine months follow-up. Quantitative angiography and IVUS showed a trend toward decreases in mean lumen diameter, vessel volume, minimum lumen area and mean lumen area at both stent edges of BMS, and at the proximal edge of SES. At the distal stent edge, a significant difference between BMS and SES treated patients in mean lumen area was found (D-0.8+/-1.6 mm2 versus D0.2+/-0.8 mm2 respectively, p=0.04). Furthermore, in-stent SES had a larger lumen volume (SES: 167.7+/-59.2 mm3 versus BMS: 125.1+/-43.8 mm3; p=0.02) and less neointima volume (7.3+/-9.1 mm3 versus 53.2+/-35.1 mm3; p<0.001). Neither SES nor BMS demonstrated a significant effect on plaque composition at follow-up VH-IVUS analysis.. A significant difference between SES and BMS treated patients was observed with respect to mean lumen diameter distal to the stented segment which suggests a downstream effect of sirolimus elution.

Topics: Adult; Aged; Angioplasty, Balloon, Coronary; Cardiovascular Agents; Coronary Angiography; Coronary Artery Disease; Drug-Eluting Stents; Female; Humans; Hyperplasia; Male; Metals; Middle Aged; Myocardial Infarction; Prosthesis Design; Sirolimus; Stents; Time Factors; Treatment Outcome; Ultrasonography, Interventional

The purpose of this study was to use intravascular ultrasound (IVUS) to investigate chronic arterial responses at the site of and adjacent to overlapping paclitaxel-eluting TAXUS stents (PES) compared with overlapping bare-metal stents (BMS).. Increased paclitaxel dose in the PES-overlap region might be associated with arterial toxicity expressed as excessive expansive remodeling, incomplete stent apposition, or aneurysm formation.. In the TAXUS-V and -VI trials, 51 patients with overlapping stents (27 PES and 24 BMS) were imaged with serial IVUS immediately after procedure and at 9 months. The IVUS measurements included intimal hyperplasia (IH), peri-stent plaque plus media (P&M), and external elastic membrane (EEM) areas. Vascular responses were assessed at the proximal and distal single stent strut regions and the central overlap region.. Compared with BMS, all 3 PES stent regions showed: 1) significantly decreased IH (proximal: 0.97 +/- 1.06 mm(2) vs. 3.12 +/- 2.40 mm(2), overlap: 0.74 +/- 0.91 mm(2) vs. 3.23 +/- 1.75 mm(2), distal: 0.88 +/- 0.85 mm(2) vs. 2.69 +/- 1.49 mm(2), all p < 0.05); and 2) increased P&M and EEM areas (Delta P&M, proximal: 0.96 +/- 1.36 mm(2) vs. -0.02 +/- 1.48 mm(2), overlap: 1.56 +/- 1.88 mm(2) vs. 0.29 +/- 1.82 mm(2), distal: 1.03 +/- 1.81 mm(2) vs. 0.11 +/- 0.89 mm(2), all p < 0.05). The IH and changes in EEM and P&M areas were not significantly different in both the BMS and PES groups comparing the single stent strut and overlap regions. Incomplete stent apposition did not occur at the site of overlapping PES in any patient.. Nine months after stent implantation, neointimal tissue growth was reduced and expansive remodeling was greater with PES compared with BMS--effects that were not exaggerated at the overlap region of PES.

Topics: Aged; Angioplasty, Balloon, Coronary; Cardiovascular Agents; Coronary Artery Disease; Coronary Vessels; Double-Blind Method; Drug-Eluting Stents; Female; Humans; Hyperplasia; Male; Metals; Middle Aged; Paclitaxel; Prospective Studies; Prosthesis Design; Stents; Time Factors; Treatment Outcome; Tunica Intima; Ultrasonography, Interventional

Wall shear stress (WSS) has been associated with neointimal hyperplasia (NIH) following bare metal stent (BMS) implantation. Drug-eluting stents (DES) almost abolish NIH. Conversely, diabetes mellitus amplifies NIH response. The association between WSS and arterial wall response following DES and BMS implantation in diabetic patients remains to be evaluated.. The study involved 20 diabetic patients randomized to BMS (n = 9) or sirolimus-eluting stent (SES; n = 11) implantation in native coronary arteries. A computational fluid dynamic model applied 3D intravascular ultrasound (IVUS) and two-plane angiographic to measure WSS (Pa). IVUS assessments were performed post-procedure and at 9-months follow-up. The target segment encompassed the stent plus 5 mm distal and proximal edges. A total of 93 subsegments were evaluated: in-stent segments divided in three subsegments (proximal, mid and distal; n = 60) and proximal and distal edges (n = 33).. Stent length was similar between BMS (17.4 +/- 7.3 mm) and SES (19.8 +/- 6.8 mm) groups. NIH was observed in all BMS subsegments (n = 27) versus one subsegment in the SES group (n = 33). WSS ranged from 0.52 to 4.20 Pa in the BMS and from 0.42 to 3.06 Pa in the SES group. There was no correlation between WSS and NIH in either stent group. In addition, there were no correlation between the change of external elastic membrane (EEM) or plaque growth at the edges and WSS.. WSS was not associated with NIH after implantation of SES or BMS in diabetic patients. Plaque growth or the change of EEM at the edges were not associated with WSS either.

Topics: Aged; Angioplasty, Balloon, Coronary; Cardiovascular Agents; Computer Simulation; Coronary Angiography; Coronary Circulation; Coronary Restenosis; Coronary Stenosis; Coronary Vessels; Diabetic Angiopathies; Drug-Eluting Stents; Female; Hemorheology; Humans; Hyperplasia; Image Interpretation, Computer-Assisted; Imaging, Three-Dimensional; Male; Metals; Middle Aged; Models, Cardiovascular; Pulsatile Flow; Sirolimus; Stents; Stress, Mechanical; Time Factors; Treatment Outcome; Ultrasonography, Interventional

Using serial intravascular ultrasound (IVUS), the efficacy of reduced-dose sirolimus-eluting stents (SESs) in the prevention of neointimal hyperplasia (NH) and maintenance of luminal patency in human coronary arteries was evaluated.. In the animal model, a broad therapeutic window regarding sirolimus doses in suppressing NH has been reported.. Serial cross-sectional and volumetric IVUS analyses were performed in 44 patients treated with SES that contained lower sirolimus doses (either 45% or 70%) than standard SES. For cross-sectional analysis, minimum lumen area (MLA) was measured. Percent (%) NH volumetric obstruction was calculated as 100 x NH volume/stent volume.. IVUS measurements were similar between the two drug-dose groups. At 12 months follow-up, only one case developed late incomplete stent apposition. Between 4 and 12 months, a slight increase of in-stent % area loss and % NH obstruction was noted (3.5% +/- 10.4% to 6.7% +/- 10.7% and 1.9% +/- 5.0% to 4.4% +/- 8.0%, respectively). The majority of studied cases, however, sustained less than a 10% volumetric (93% of studied cases) and area loss (75% of studied cases) in the stented segment up to 12 months. At 12 months, % area loss within the stented segments and 5-mm reference segments were comparable (7.0% +/- 19.6% versus 6.7% +/- 10.7%).. Although slight increases of NH were noted, SESs, delivering two reduced drug doses, appeared to be effective for maintaining luminal patency during 12 months follow-up.

Topics: Angioplasty, Balloon, Coronary; Cardiovascular Agents; Coronary Artery Disease; Coronary Restenosis; Coronary Vessels; Dose-Response Relationship, Drug; Drug-Eluting Stents; Humans; Hyperplasia; Sirolimus; Time Factors; Treatment Outcome; Tunica Intima; Ultrasonography, Interventional; Vascular Patency

The aim of this intravascular ultrasound (IVUS) study was to assess the efficacy of the AXXESS Plus stent system for the treatment of bifurcation coronary lesions.. The AXXESS Plus is a novel bifurcation drug-eluting stent, comprised of a self-expanding flare-shaped stent platform and bioabsorbable polymer coating that releases Biolimus A9.. Data were obtained from the AXXESS PLUS trial, a prospective, multicenter, nonrandomized, single-arm study to evaluate safety and efficacy. Six-month follow-up IVUS analysis was available in 49 cases. Volumetric analysis using Simpson's method within the AXXESS stent, and cross-sectional analysis at the ostium of main branch and/or side branch was performed. Impact of bifurcation angle on stent expansion at the carina was also evaluated.. Within the AXXESS stent, neointimal volume obstruction percentage was 2.3% +/- 2.2%, with a minimum lumen area of 7.9 +/- 2.6 mm(2). Lumen area was 5.2 +/- 1.7 mm(2) at main branch ostium, and 4.0 +/- 1.5 mm(2) at side branch ostium. In two cases, incomplete stent apposition was observed at the proximal edge of the AXXESS stent. In one case, a gap between the AXXESS stent and an additional stent was observed. Greater bifurcation angle inversely correlated with smaller stent area at side branch ostium (r = -0.54, P = 0.03) but not at main branch ostium (r = -0.2, P = 0.29).. This novel self-expanding, drug-eluting bifurcation stent demonstrated effective lesion coverage along with significant neointimal suppression equivalent to current generation balloon-expandable drug-eluting stent technology.

Topics: Aged; Angioplasty, Balloon, Coronary; Cardiovascular Agents; Coronary Artery Disease; Coronary Restenosis; Coronary Vessels; Drug-Eluting Stents; Female; Humans; Hyperplasia; Male; Middle Aged; Prospective Studies; Prosthesis Design; Sirolimus; Time Factors; Treatment Outcome; Tunica Intima; Ultrasonography, Interventional

Drug-eluting stent (DES) strut fracture (SF) is associated with higher incidence of In-stent restenosis (ISR)-return of blockage in a diseased artery post stenting-than seen with bare metal stents (BMS). We hypothesize that concomitance of drug and SF leads to greater neointimal response.. Controlled release of therapeutic agents, such as sirolimus and its analogs, or paclitaxel from has reduced tissue based DES failure modes compared to BMS. ISR is dramatically reduced and yet the implications of mechanical device failure is magnified.. Bilateral Xience Everolimus-eluting stents (EES) were implanted in 20 New Zealand White rabbits on normal (n = 7) or high fat (HF)/high cholesterol (HC) (n = 13) diets. Implanted stents were intact or mechanically fractured. Everolimus concentration was as packaged or pre-eluted. After 21 days, stented vessels were explanted, resin embedded, MicroCT scanned, and analyzed histomorphometrically.. Fractured EES were associated with significant (P < 0.05) increases in arterial stenosis and neointimal formation and lower lumen-to-artery area ratios compared to intact EES. Hyperlipidemic animals receiving pre-eluted EES revealed no significant difference between intact and fracture groups.. SF increases intimal hyperplasia, post EES implant, and worse with more advanced disease. Pre-eluted groups, reflective of BMS, did not show significant differences, suggesting a synergistic effect of everolimus and mechanical injury, potentially explaining the lack of SF reports for BMS. Here, we report that ISR has a higher incidence with SF in EES, the clinical implication is that patients with SF after DES implantation merit careful follow-up.

Topics: Animals; Atherosclerosis; Cardiovascular Agents; Cholesterol, Dietary; Diet, High-Fat; Disease Models, Animal; Drug-Eluting Stents; Endovascular Procedures; Everolimus; Hyperplasia; Iliac Artery; Neointima; Prosthesis Design; Prosthesis Failure; Rabbits; Time Factors

Intimal hyperplasia (IH) is the most common indicator for secondary intervention in peripheral vascular disease. Matrix metalloproteinases (MMPs) play a role in IH development due to their degradation of the extracellular matrix. Doxycycline (Doxy), a member of the tetracycline family of antibiotics, is a potent MMP inhibitor. We have previously shown that Doxy inhibits MMP activity and vascular smooth muscle cell migration in vitro. We hypothesized that Doxy would decrease MMP activity in vivo and inhibit the development of IH in a rodent model of vascular injury.. Doxy (400 mg/pellet) was delivered by a slow-release pellet implanted 3 days prior to or at the time of balloon angioplasty (BA) of the common carotid artery in female rats. At 14 days post-BA, intima-to-media (I:M) ratios were 0.77 ± 0.21 and 1.04 ± 0.32 in the Doxy treated groups, respectively, compared to 1.25 ± 0.26 in the control group (P = not significant; n = 3). Additionally, the tested dose of Doxy in either group had no inhibitory effect on membrane type 1-MMP or MMP-2 tissue levels, as measured by immunohistochemistry, or on systemic levels of MMP, as measured by total MMP serum levels using enzyme-linked immunosorbent assay. At 14 days post-BA, VSMC proliferation in the injured artery was increased to Doxy treatment prior to and at the time of surgery (23.5 ± 3.4 and 27.2 ± 3.9%, respectively), compared to control (11.4 ± 0.4%; n = 3), as measured by proliferating cellular nuclear antigen immunostaining.. In our in vivo model of vascular injury, systemic Doxy administration prior to or at the time of vascular injury does not significantly hinder the progression of IH development. Additional doses and routes of administration could be examined in order to correlate therapeutic serum levels of Doxy with effective MMP inhibition in serum and arterial tissue. However, alternative drug delivery systems are needed in order to optimize therapeutic administration of targeted MMP inhibitors for the prevention of IH development.

Topics: Angioplasty, Balloon; Animals; Cardiovascular Agents; Carotid Artery Injuries; Carotid Artery, Common; Cell Proliferation; Disease Models, Animal; Doxycycline; Female; Hyperplasia; Matrix Metalloproteinase 14; Matrix Metalloproteinase 2; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Neointima; Rats, Sprague-Dawley

The aim of this study was to compare neointima proliferation in three drug-eluting stents (DES) produced by the same company (Balton, Poland) which are covered with a biodegradable polymer and elute sirolimus (concentration: 1.0 and 1.2 µg/mm

Topics: Absorbable Implants; Aged; Cardiovascular Agents; Cell Proliferation; Coronary Angiography; Coronary Artery Disease; Coronary Vessels; Drug-Eluting Stents; Female; Humans; Hyperplasia; Male; Middle Aged; Neointima; Percutaneous Coronary Intervention; Polymers; Predictive Value of Tests; Prosthesis Design; Risk Factors; Sirolimus; Time Factors; Tomography, Optical Coherence; Treatment Outcome

Vascular smooth muscle cell (VSMC) proliferation and migration are crucial events in the pathological course of restenosis after percutaneous coronary intervention (PCI). N-oleoylethanolamide (OEA) is a bioactive lipid amide released upon dietary fat digestion with many reported actions. However, the effect of OEA on restenosis after vascular injury remains unknown. Here, we investigated the effects of OEA on intimal hyperplasia after balloon injury in vivo, its effect on VSMC proliferation and migration induced by platelet-derived growth factor (PDGF) stimulation in vitro, and the underlying mechanism underlying these effects. The results showed that OEA-treated rats displayed a significant reduction in neointima formation after balloon injury. In cultured VSMCs, treatment with OEA decreased cell proliferation and migration induced by PDGF. OEA treatment both in vivo and in vitro led to an increase in adenosine monophosphate-activated protein kinase (AMPK) phosphorylation and peroxisome proliferator-activated receptor alpha (PPARα), and a decrease in proliferating cell nuclear antigen (PCNA) and cyclinD1 expression. Pharmacological inhibition of AMPK and PPARα reversed the suppressive effects of OEA on VSMC proliferation and migration, suggesting that the suppressive effect of OEA on VSMC proliferation and migration is mediated through the activation of AMPK and PPARα. In conclusion, our present study demonstrated that OEA attenuated neointima formation in response to balloon injury by suppressing SMC proliferation and migration through an AMPK and PPARα-dependent mechanism. Our data suggests that OEA may be a potential therapeutic agent for restenosis after PCI.

Topics: AMP-Activated Protein Kinases; Animals; Cardiovascular Agents; Carotid Artery Injuries; Carotid Artery, Common; Cell Movement; Cell Proliferation; Cell Survival; Cyclin D1; Endocannabinoids; Endothelial Cells; Hyperplasia; Male; Muscle, Smooth, Vascular; Neointima; Oleic Acids; Phosphorylation; Platelet-Derived Growth Factor; PPAR alpha; Primary Cell Culture; Proliferating Cell Nuclear Antigen; Rats; Rats, Sprague-Dawley; Tunica Intima

Carotid artery web is considered an exceptional cause of recurrent ischemic strokes in the affected arterial territory. The underlying pathology proposed for this entity is an atypical fibromuscular dysplasia. We present the case of a 43-year-old woman with no cardiovascular risk factors who had experienced 2 cryptogenic ischemic strokes in the same arterial territory within an 11-month period. Although all diagnostic tests initially yielded normal results, detailed analysis of the computed tomography angiography images revealed a carotid web; catheter angiography subsequently confirmed the diagnosis. Carotid surgery was performed, since which time the patient has remained completely asymptomatic. The histological finding of intimal hyperplasia is consistent with previously reported cases of carotid artery web. Carotid artery web is an infrequent cause of stroke, and this diagnosis requires a high level of suspicion plus a detailed analysis of vascular imaging studies.

Topics: Adult; Aspirin; Atorvastatin; Biopsy; Brain Ischemia; Cardiovascular Agents; Carotid Artery Diseases; Carotid Artery, Internal; Computed Tomography Angiography; Female; Fibromuscular Dysplasia; Humans; Hyperplasia; Neointima; Recurrence; Risk Factors; Stroke

We aimed to investigate the safety and efficacy of XINSORB bioresorbable sirolimus-eluting scaffold in porcine model. XINSORB scaffolds and metallic Firebird2™ stents were randomly implanted into minipigs' coronary arteries. Angiography, optical coherent tomography (OCT) and histopathological analyses were performed at post-procedure and 14-, 28-, 90-, 180-day follow-up. Thirty-two minipigs were enrolled. Eight XINSORB scaffolds and 8 Firebird2 stents were examined at each time point. Quantitative coronary angiography showed that in-scaffold late luminal loss (LLL) of XINSORB scaffold was 0.26 ± 0.13, 0.50 ± 0.16, 0.88 ± 0.29 and 0.43 ± 0.24 mm at 14-, 28, 90-, and 180-day follow-up respectively, and the corresponding diameter stenosis (DS) was 7.3 ± 4.7, 12.0 ± 9.5, 22.1 ± 8.0, and 16.0 ± 9.5%. Neither in-scaffold LLL nor DS of XINSORB scaffold was significantly different in comparison with Firebird2 stent. No difference of luminal area, device area, neointimal hyperplasia, and area stenosis was detected between two devices under OCT. Scaffold area of XINSORB remained steady through the observation. Histopathology revealed the similar findings. The greatest late recoil of XINSORB scaffold was about 4.12% at 90-day follow-up, which was comparable to Firebird2 stent. Both devices showed low injury or inflammation of vessel wall. XINSORB scaffold showed early neointimal coverage on struts within 28 days under scanning electron microscopy. XINSORB scaffold suppressed neointimal hyperplasia as effectively as Firebird2 did without obvious late device recoil during the 180 days follow-up. It is feasible to carry out clinical trial to investigate the safety and efficacy of XINSORB scaffold for patients with coronary artery diseases.

Topics: Animals; Cardiac Catheterization; Cardiovascular Agents; Coated Materials, Biocompatible; Coronary Angiography; Coronary Vessels; Drug-Eluting Stents; Hyperplasia; Metals; Microscopy, Electron, Scanning; Models, Animal; Neointima; Percutaneous Coronary Intervention; Prosthesis Design; Prosthesis Failure; Sirolimus; Swine; Swine, Miniature; Time Factors; Tomography, Optical Coherence

Lipid mediators derived from omega-3 polyunsaturated fatty acids such as resolvin D1 (RvD1) accelerate the resolution of inflammation and have potential as vascular therapeutics. The objective of this study was to evaluate local perivascular delivery of RvD1 as a means to attenuate neointimal hyperplasia in a rat model of arterial injury.. Smooth muscle cells were harvested from rat aortas to study the effects of RvD1 on rat arterial vascular smooth muscle cell responses in vitro, with focus on inflammation, proliferation, migration, cytoskeletal changes, and cytotoxicity. The safety and efficacy of perivascular delivery of RvD1 through thin biodegradable three-layered poly(lactic-co-glycolic acid) wraps or 25% Pluronic F127 gels were studied in a rat model of carotid angioplasty. A total of 200 ng of RvD1 was loaded into each construct for perivascular delivery after injury. Morphometric and histologic analyses were performed 3 and 14 days after injury.. RvD1 attenuated rat arterial vascular smooth muscle cell inflammatory pathways, proliferation, migration, and mitogen-induced cytoskeletal changes in vitro, without evidence of cytotoxicity. RvD1-loaded wraps reduced neointimal formation after carotid angioplasty by 59% vs no-wrap controls (P = .001) and by 45% vs vehicle-wrap controls (P = .002). RvD1-loaded Pluronic gels similarly reduced neointimal formation by 49% vs no-gel controls (P = .02) and by 52% vs vehicle-gel controls (P = .02). No group was associated with infection, thrombosis, or negative vessel remodeling. Wraps were found to be easier to apply than gel constructs. Ki67 proliferation index was significantly lower in RvD1-loaded wrap-treated arteries compared with both no-wrap and vehicle-wrap controls at both 3 and 14 days after injury (65% vs no-wrap group and 70% vs vehicle-wrap group at day 3, 49% vs both control groups at day 14; P < .05). Similarly, oxidative stress (30% and 29%; P < .05) and nuclear factor κB activation (42% and 45%; P < .05) were significantly lower in the RvD1-loaded wrap group compared with both no-wrap and vehicle-wrap controls at 3 days after injury.. Local perivascular delivery of RvD1 attenuates formation of neointimal hyperplasia without associated toxicity in a rat model of carotid angioplasty. This effect is likely due to attenuation of inflammatory pathways as well as decreased arterial smooth muscle cell proliferation and migration.

Topics: Angioplasty, Balloon; Animals; Aorta; Cardiovascular Agents; Carotid Artery Diseases; Cell Movement; Cell Proliferation; Cells, Cultured; Cytoskeleton; Disease Models, Animal; Docosahexaenoic Acids; Drug Carriers; Drug Compounding; Hyperplasia; Inflammation Mediators; Ki-67 Antigen; Lactic Acid; Male; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Neointima; Oxidative Stress; Poloxamer; Polyglycolic Acid; Polylactic Acid-Polyglycolic Acid Copolymer; Rats, Sprague-Dawley; Time Factors; Transcription Factor RelA

Neointimal hyperplasia (NIH) remains one of the leading causes of graft failure after vascular anastomoses. Cytotoxic drugs, such as rapamycin and tacrolimus, have been shown to inhibit the development of NIH. In this study, the aim was to test the impact of a sustained releasing tacrolimus-chitosan-eluting suture on the development of NIH in a rat model.. In vitro tacrolimus release tests for a 7/0 tacrolimus-chitosan coated PVDF suture were confirmed for 1 month without an initial burst release. Endothelialisation over the aortotomy line occurred in both groups. The area of neointima was significantly reduced in group T compared with group C (ratio 0.22 ± 0.12 vs. 0.42 ± 0.11; p = .017) 1 month post-operatively. Likewise, the percentage of PCNA immunostaining significantly decreased in group C compared with group T (3.83 ± 2.85% vs. 11.17 ± 7.78%; p = .026). The cells constituting NIH were positive for ASMA immunostaining.. Tacrolimus-chitosan-eluting suture is shown to be an effective way to reduce NIH without interfering with normal endothelialisation.

Topics: Actins; Animals; Aorta; Cardiovascular Agents; Coated Materials, Biocompatible; Equipment Design; Hyperplasia; Male; Neointima; Proliferating Cell Nuclear Antigen; Rats, Wistar; Solubility; Suture Techniques; Sutures; Tacrolimus; Time Factors

Restenosis due to intimal hyperplasia is a major clinical problem that compromises the success of angioplasty and endovascular surgery. Resveratrol (RSV) has demonstrated a beneficial effect on restenosis from angioplasty. Unfortunately, the physicochemical characteristics of RSV reduce the practicality of its immediate clinical application. This work proposes an experimental model aiming to setup an intravessel, elutable, RSV-containing compound.. A 140 μg/mL RSV sterile injectable solution with a suitable viscosity for intravascular administration by drug-delivery catheter (RSV-c) was prepared. This solution was locally administered in the common iliac artery of adult male New Zealand White rabbits using a dedicated device (Genie; Acrostak, Geneva, Switzerland) after the induction of intimal hyperplasia by traumatic angioplasty. The RSV concentrations in the wall artery were determined, and the thickness of the harvested iliac arteries was measured over a 1-month period.. The Genie catheter was applied in rabbit vessels, and the local delivery resulted in an effective reduction in restenosis after plain angioplasty. Notably, RSV-c forced into the artery wall by balloon expansion might accumulate in the interstitial areas or within cells, avoiding the washout of solutions. Magnification micrographs showed intimal proliferation was significantly inhibited when RSV-c was applied. Moreover, no adverse events were documented in in vitro or in vivo studies.. RSV can be advantageously administered in the arterial walls by a drug-delivery catheter to reduce the risk of restenosis.

Topics: Angioplasty, Balloon; Animals; Cardiovascular Agents; Cell Proliferation; Cells, Cultured; Coated Materials, Biocompatible; Disease Models, Animal; Equipment Design; Humans; Hyperplasia; Iliac Artery; Male; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Neointima; Rabbits; Resveratrol; Stilbenes; Vascular Access Devices; Vascular System Injuries

Restenosis due to intimal hyperplasia (IH) is a major clinical issue that affects the success of lower limb endovascular surgery. After 1 year, restenosis occurs in 40% to 60% of the treated vessels. The possibility to reduce IH using local antiproliferative drugs, such as taxols, has been the rationale for the clinical applications of drug-eluting stents and drug-eluting balloons (DEBs). The purpose of this study was to evaluate the clinical and instrumental efficacy of DEBs versus simple percutaneous transluminal angioplasty (PTA) in patients affected by chronic limb ischemia (CLI) with tibial artery "de novo" lesions.. A retrospective analysis was performed and included all consecutive patients who underwent endovascular treatment for CLI in our centers between January 2011 and March 2013. Inclusion criteria were (1) "de novo" tibial artery stenosis and (2) Rutherford class >4. Lesions were further divided by TransAtlantic Inter-Societal Consensus (TASC) classification into groups A, B, C, and D.. Between January 2010 and March 2013, a total of 138 patients underwent simple PTA or DEB for CLI, and the groups were clinically and demographically homogenous. We decided to use DEBs in 70 cases. An improvement in the Rutherford Scale in cumulative and single TASC lesions classification was better in the DEB group (74% vs 51%; P = .024) at 24 months than in the PTA group. In the DEB group, the increase in ankle-brachial index was significantly higher than in the PTA group (P = .039).. Our experience in addition to the existing literature supports the use of DEB in patients with CLI Rutherford class >3.

Topics: Aged; Amputation, Surgical; Angioplasty, Balloon; Ankle Brachial Index; Cardiovascular Agents; Coated Materials, Biocompatible; Equipment Design; Europe; Female; Humans; Hyperplasia; Ischemia; Limb Salvage; Lower Extremity; Male; Middle Aged; Neointima; Peripheral Arterial Disease; Recurrence; Retrospective Studies; Tibial Arteries; Time Factors; Treatment Outcome; Vascular Access Devices

The local delivery of paclitaxel onto a graft has been reported to prevent neointimal hyperplasia. Because more than half of vascular stenoses occur within 3 cm of the venous anastomosis, this study tested the effectiveness of a paclitaxel coating restricted to both ends of the expanded polytetrafluoroethylene (ePTFE) graft to reduce the amount of drug delivered.. Both ends of ePTFE grafts were coated with paclitaxel at a dose of 0.58 μg/mm(2); the total amount of paclitaxel per graft was 0.66 mg. Paclitaxel-coated hemodialysis grafts 15 cm in length were surgically implanted between the common carotid artery and external jugular vein in female Landrace pigs. The animals were sacrificed 6 weeks after graft placement. Cross sections of the anastomosis sites were analyzed histomorphometrically to measure the ratio of neointimal hyperplasia to the graft area (H/G ratio) and the percentage of luminal stenosis. The experimental results were compared between grafts coated with paclitaxel at the ends only (n = 8), grafts coated over the entire length (n = 6), and uncoated control grafts (n = 6).. The mean ± standard error values of the H/G ratios for the arterial anastomosis were 0.82 ± 0.13 (control), 0.41 ± 0.09 (terminal coating), and 0.21 ± 0.04 (whole coating). The values for the venous anastomosis were 0.82 ± 0.12 (control), 0.39 ± 0.11 (terminal coating), and 0.12 ± 0.03 (whole coating). Compared with the uncoated grafts, neointimal hyperplasia was suppressed effectively in the vascular grafts coated terminally with paclitaxel (artery, P = 050; vein, P < .001). However, the suppressive effect was less than that of grafts coated with paclitaxel over the entire length. The percentages of luminal stenosis showed similar tendency to the H/G ratios.. Despite a reduced amount of the drug, paclitaxel coating applied to both ends of the ePTFE hemodialysis grafts effectively suppressed neointimal hyperplasia at the sites of anastomosis.

Topics: Animals; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Cardiovascular Agents; Carotid Artery, Common; Coated Materials, Biocompatible; Constriction, Pathologic; Disease Models, Animal; Female; Graft Occlusion, Vascular; Hyperplasia; Jugular Veins; Neointima; Paclitaxel; Polytetrafluoroethylene; Prosthesis Design; Renal Dialysis; Swine; Time Factors

This study investigated p aclitaxel-induced luminal changes following drug-coated balloon (DCB) angioplasty to treat coronary de novo lesions without additional stenting. DCB-mediated local drug delivery reduces late lumen loss in de novo coronary artery lesions. We performed a retrospective clinical assessment based on a pre-specified quantitative coronary angiography (QCA) protocol.. QCA was performed for each centre to assess the primary endpoint late lumen changes, i.e. the difference between in-lesion minimal lumen diameter (MLD) at the routine angiographic follow-up as compared to post-procedural in-lesion MLDs. These MLD changes were compared to corresponding reference vessel diameter changes as an intra-patient control.. We evaluated 58 consecutive native coronary artery lesions directly after DCB angioplasty and at a routine target follow-up angiography of 4 months by QCA. Target lesion MLD increased significantly within the 4.1 ± 2.1 month observation period (1.75 ± 0.55 vs. 1.91 ± 0.55 mm, p < 0.001, diameter stenosis 33.8 ± 12.3 vs. 26.9 ± 13.8 %, p < 0.001), while there were no changes in non-target reference vessel diameters (2.33 ± 0.60 vs. 2.34 ± 0.61 mm, p = ns). A total of 69 % of patients showed luminal enlargement whereas 29 % had minor luminal loss.. Local application of paclitaxel by DCB angioplasty to native coronary arteries after pre-dilatation without major dissection and recoil leads to late lumen increase.

Topics: Aged; Angioplasty, Balloon, Coronary; Cardiac Catheters; Cardiovascular Agents; Coated Materials, Biocompatible; Coronary Angiography; Coronary Artery Disease; Coronary Restenosis; Coronary Vessels; Female; Humans; Hyperplasia; Male; Middle Aged; Neointima; Paclitaxel; Retrospective Studies; Time Factors; Treatment Outcome; Vascular Remodeling

New paclitaxel coated balloons (PCB) developments have been proposed to maintain therapeutic levels of drug in the tissue while decreasing particle release. In this series of studies, we evaluated the pharmacokinetic profile and biological effects after paclitaxel delivery via novel microcrystalline PCB coating (mcPCB, Pax®, Balton) in porcine iliofemoral arteries.. Ten domestic swine were enrolled yielding 24 iliofemoral segments for evaluation. In the pharmacokinetic study, nine mcPCBs were dilated for 60 sec and animals sacrificed after 1 hr, 3 and 7 days. Studied segments were harvested and tissue paclitaxel concentration was analyzed utilizing HPLC. In the biological response evaluation, self-expandable stents were implanted followed by post dilation with either mcPCB (n = 10) or POBA (n = 5). After 28 days, angiography was performed, animals were sacrificed and stented segments harvested for histopathological evaluation.. The 1-hr, 3 and 7 days vessel paclitaxel concentrations were 152.9 ± 154.5, 36.5 ± 49.5, and 0.9 ± 0.7 ng/mg respectively. In the biological response study, stents in the mcPCB group presented lower angiographic measures of neointimal hyperplasia as expressed by late loss when compared to POBA (-0.43 ± 0.9 vs. 0.23 ± 1.2; P = 0.24) at 28 days. In the histopathological evaluation, percent area of stenosis (%AS) was reduced by 42% in the mcPCB group (P < 0.05). The healing process in mcPCB group was comparable to POBA with regard to fibrin deposition (0.7 vs. 0.7; P = ns), neointimal maturity (1.97 vs. 1.93; P = ns), inflammation score (0.92 vs. 1; P = ns) and endothelialization score (1.77 vs. 1.73; P = ns). The mcPCB group did however display a greater tendency of medial cell loss and mineralization (60% vs. 0; P = 0.08).. Delivery of paclitaxel via a novel mcPCB resulted in low long-term tissue retention of paclitaxel. However, this technological approach displayed reduced neointimal proliferation and favorable healing profile.

Topics: Angioplasty, Balloon; Animals; Cardiovascular Agents; Cell Proliferation; Chromatography, High Pressure Liquid; Coated Materials, Biocompatible; Crystallization; Drug-Eluting Stents; Female; Femoral Artery; Hyperplasia; Iliac Artery; Male; Materials Testing; Models, Animal; Neointima; Paclitaxel; Prosthesis Design; Radiography; Sus scrofa; Wound Healing

Intimal hyperplasia produces restenosis (re-narrowing) of the vessel lumen following vascular intervention. Drugs that inhibit intimal hyperplasia have been developed, however there is currently no clinical method of perivascular drug-delivery to prevent restenosis following open surgical procedures. Here we report a poly(ε-caprolactone) (PCL) sheath that is highly effective in preventing intimal hyperplasia through perivascular delivery of rapamycin. We first screened a series of bioresorbable polymers, i.e., poly(lactide-co-glycolide) (PLGA), poly(lactic acid) (PLLA), PCL, and their blends, to identify desired release kinetics and sheath physical properties. Both PLGA and PLLA sheaths produced minimal (<30%) rapamycin release within 50days in PBS buffer. In contrast, PCL sheaths exhibited more rapid and near-linear release kinetics, as well as durable integrity (>90days) as evidenced in both scanning electron microscopy and subcutaneous embedding experiments. Moreover, a PCL sheath deployed around balloon-injured rat carotid arteries was associated with a minimum rate of thrombosis compared to PLGA and PLLA. Morphometric analysis and immunohistochemistry revealed that rapamycin-loaded perivascular PCL sheaths produced pronounced (85%) inhibition of intimal hyperplasia (0.15±0.05 vs 1.01±0.16), without impairment of the luminal endothelium, the vessel's anti-thrombotic layer. Our data collectively show that a rapamycin-loaded PCL delivery system produces substantial mitigation of neointima, likely due to its favorable physical properties leading to a stable yet flexible perivascular sheath and steady and prolonged release kinetics. Thus, a PCL sheath may provide useful scaffolding for devising effective perivascular drug delivery particularly suited for preventing restenosis following open vascular surgery.

Topics: Animals; Cardiovascular Agents; Carotid Artery Injuries; Carotid Stenosis; Cell Proliferation; Chemistry, Pharmaceutical; Delayed-Action Preparations; Disease Models, Animal; Drug Carriers; Hyperplasia; Kinetics; Linear Models; Male; Neointima; Polyesters; Rats; Rats, Sprague-Dawley; Sirolimus; Solubility; Technology, Pharmaceutical

To evaluate the potential role, safety, and efficacy of paclitaxel-eluting balloon angioplasty for treatment of recurrent carotid in-stent restenosis (ISR).. Among 856 consecutive patients who underwent carotid artery stenting from May 2002 to January 2008, 41 patients had a significant ISR (>80% stenosis). Of these, 9 patients (7 women; mean age 78.1±5.6 years) had recurrent ISR despite multiple endovascular treatments (3.4±0.9 interventions) within a short period of time (2-5 months). These patients were treated with drug-eluting balloon (DEB) angioplasty for neointimal hyperplasia. Imaging (ultrasound or computed tomographic angiography) was performed at 1, 3, and 6 months and yearly thereafter.. Technical success was obtained in 100% of cases, with angiographic stenosis decreasing from 87%±4% to 6%±4% post treatment. Peak systolic velocity decreased significantly from 4.7±1.5 m/s to 0.6.±0.3 m/s after the procedure. Over a mean follow-up of 36.6±2.7 months, ultrasound imaging indicated recurrent ISR in only 3 patients at 18, 25, and 32 months after DEB angioplasty, respectively. The target vessel revascularization rate was 33.3% at 36 months. No neurological or myocardial events were recorded during follow-up. One patient died at 3 months.. DEB may have a potential role improving outcomes of those patients treated for early recurrent carotid ISR.

Topics: Aged; Angioplasty, Balloon; Blood Flow Velocity; Cardiovascular Agents; Carotid Stenosis; Drug-Eluting Stents; Endovascular Procedures; Female; Humans; Hyperplasia; Male; Middle Aged; Neointima; Paclitaxel; Prosthesis Design; Recurrence; Regional Blood Flow; Retreatment; Risk Factors; Stents; Time Factors; Tomography, X-Ray Computed; Treatment Outcome; Ultrasonography, Doppler; Vascular Patency

Two patients who underwent simultaneous kissing stenting with sirolimus-eluting stents in the left main coronary artery were investigated with optical coherence tomography (OCT) at just more than 1 year postoperatively. In both cases, follow-up angiogram indicated complete coverage of the new metal carina with a membranous diaphragm, yet OCT showed varying tissue-coverage patterns transitioning from stent inflow to stent outflow. These patterns included single-strut coverage, bridge-like membrane formation between more than 1 strut, and end-to-end coverage of the carina; no uncovered stent struts were detected. OCT also demonstrated mixed patterns of tissue characteristics on the metal carina, ranging from poor endothelialization to modest neointima formation. These varying tissue characteristics suggest that the process of tissue coverage in the metal carina is different from that occurring on the vessel wall; this may indicate delayed healing in the carina.

Topics: Aged; Aged, 80 and over; Cardiovascular Agents; Coronary Angiography; Coronary Artery Disease; Coronary Vessels; Drug-Eluting Stents; Endothelium, Vascular; Female; Humans; Hyperplasia; Neointima; Percutaneous Coronary Intervention; Predictive Value of Tests; Prosthesis Design; Sirolimus; Time Factors; Tomography, Optical Coherence; Treatment Outcome

Epigallocatechin-3-gallate (EGCG), a catechin gallate ester, is the major component of green tea and has been demonstrated to inhibit tumor growth as well as inhibit smooth muscle cell migration. We evaluated the effect of the phytochemicals resveratrol, allicin, sulforaphane (SFN), and EGCG on intimal hyperplasia in the carotid artery injury model.. Intimal hyperplasia was induced in carotid arteries of adult Sprague-Dawley rats with a wire injury. Experimental animals received intraperitoneal injections of one of the four phytochemicals daily beginning 1 day prior to surgery and continued for up to 4 weeks. Control animals were administered saline. Carotid specimens were harvested at 2 weeks and subjected to quantitative image analysis. In addition, EGCG specimens were analyzed for cell proliferation, immunohistochemistry, and Western blot analysis.. Quantitative image analysis showed significant phytochemical suppression of intimal hyperplasia at 2 and 4 weeks postoperatively with EGCG (62% decrease in intimal area). Significant decreases were also noted at 2 weeks for SFN (56%) and resveratrol (44%), whereas the decrease with allicin (24%) was not significant. Quantification of intimal hyperplasia by intima:media ratio showed similar results. Cell proliferation assay of specimens demonstrated suppression by EGCG. Immunohistochemical staining of EGCG-treated specimens showed extracellular signal-regulated kinase (ERK) suppression but not of the c-jun N-terminal kinase or p38 pathways. Western blot analysis confirmed reduced ERK activation in arteries treated with EGCG.. Intraperitoneal injection of the phytochemicals EGCG, SFN, resveratrol, and allicin have suppressive effects on the development of intimal hyperplasia in the carotid artery injury model, with maximal effect due to EGCG. The mechanism of EGCG action may be due to inhibition of ERK activation. EGCG may affect a common pathway underlying either neoplastic cellular growth or vascular smooth muscle cellular proliferation.

Topics: Animals; Cardiovascular Agents; Carotid Artery Injuries; Carotid Artery, Common; Carotid Intima-Media Thickness; Catechin; Cell Proliferation; Disease Models, Animal; Disulfides; Enzyme Activation; Extracellular Signal-Regulated MAP Kinases; Hyperplasia; Injections, Intraperitoneal; Isothiocyanates; Male; Neointima; Protein Kinase Inhibitors; Rats; Rats, Sprague-Dawley; Resveratrol; Stilbenes; Sulfinic Acids; Sulfoxides; Time Factors

Sirolimus (rapamycin) is used in drug-eluting stent strategies and proved clearly superior in this application compared with other immunomodulators such as pimecrolimus. The molecular basis of this action of sirolimus in the vascular system is still incompletely understood. Measurements of cell proliferation in human coronary artery smooth muscle cells (hCASM) demonstrated a higher antiproliferative activity of sirolimus compared with pimecrolimus. Although sirolimus lacks inhibitory effects on calcineurin, nuclear factor of activated T-cell activation in hCASM was suppressed to a similar extent by both drugs at 10 μM. Sirolimus, but not pimecrolimus, inhibited agonist-induced and store-operated Ca(2+) entry as well as cAMP response element binding protein (CREB) phosphorylation in human arterial smooth muscle, suggesting the existence of an as-yet unrecognized inhibitory effect of sirolimus on Ca(2+) signaling and Ca(2+)-dependent gene transcription. Electrophysiological experiments revealed that only sirolimus but not pimecrolimus significantly blocked the classical stromal interaction molecule/Orai-mediated, store-operated Ca(2+) current reconstituted in human embryonic kidney cells (HEK293). A link between Orai function and proliferation was confirmed by dominant-negative knockout of Orai in hCASM. Analysis of the effects of sirolimus on cell proliferation and CREB activation in an in vitro model of arterial intervention using human aorta corroborated the ability of sirolimus to suppress stent implantation-induced CREB activation in human arteries. We suggest inhibition of store-operated Ca(2+) entry based on Orai channels and the resulting suppression of Ca(2+) transcription coupling as a key mechanism underlying the antiproliferative activity of sirolimus in human arteries. This mechanism of action is specific for sirolimus and not a general feature of drugs interacting with FK506-binding proteins.

Topics: Aorta; Calcium Channels; Calcium Signaling; Cardiovascular Agents; Cell Proliferation; Coronary Vessels; Cyclic AMP Response Element-Binding Protein; Dose-Response Relationship, Drug; Gene Knockout Techniques; HEK293 Cells; Humans; Hyperplasia; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; NFATC Transcription Factors; ORAI1 Protein; Phosphorylation; Sirolimus; Stents; Tacrolimus; Time Factors; Tissue Culture Techniques; Transcription, Genetic; Transfection

This study sought to assess stent-vessel interactions after drug-eluting stent (DES) implantation in unprotected left main coronary artery (ULM) by frequency-domain optical coherence tomography (FD-OCT).. Percutaneous coronary intervention using DES in ULM has been increasingly performed in routine practice. Recently, FD-OCT assessments of DES-vessel interactions have been used as surrogates for DES safety; however, there are no FD-OCT studies in ULM.. We prospectively enrolled 33 consecutive patients with ULM disease treated with sirolimus- (n = 11) and everolimus-eluting stents (n = 22). FD-OCT assessments were performed post-percutaneous coronary intervention and at 9-month follow-up. Three different segments of ULM were compared: distal (DIS), bifurcation (BIF), and ostial-body (BODY). The primary endpoints were percentages of uncovered and malapposed struts at 9-month follow-up, and the secondary endpoint was neointimal hyperplasia area.. We analyzed 25,873 stent struts. Significant differences were demonstrated for percentage of uncovered struts (3.4%, 11.7%, and 18.7%, respectively for DIS, BIF, and BODY; p < 0.05 for all the comparisons). Malapposition was also more common in BODY (5.3%) than in DIS (0.6%) and BIF (2.0%) segments (p < 0.05 for BODY vs. DIS, and BODY vs. BIF). Equivalent neointimal hyperplasia areas were demonstrated in all segments. Acute malapposition rates led to different patterns of DES-vessel interactions at 9-month follow-up.. Distinct patterns of DES-vessel interactions were demonstrated in different segments of ULM. Acute stent strut malapposition affects these findings.

Topics: Aged; Cardiovascular Agents; Coronary Artery Disease; Coronary Vessels; Drug-Eluting Stents; Everolimus; Female; Humans; Hyperplasia; Male; Middle Aged; Neointima; Percutaneous Coronary Intervention; Predictive Value of Tests; Prospective Studies; Prosthesis Design; Sirolimus; Time Factors; Tomography, Optical Coherence; Treatment Outcome

Recent studies reported favorable angiographic and clinical outcomes after everolimus-eluting stent (EES) implantation. However, there were no studies to assess vascular responses after EES implantation using optical coherence tomography (OCT). Therefore, the OCT findings in EES were investigated and compared with those in sirolimus-eluting stent (SES). Follow-up OCT studies were performed in 110 lesions (40 EES and 70 SES) of 104 patients at 9 months after stent implantation. The strut apposition, neointimal hyperplasia (NIH) thickness and stent coverage on each stent struts were evaluated. The mean NIH thickness was significantly greater in EES-treated lesions than in SES-treated lesions (115 ± 52 μm vs. 89 ± 58 μm, P = 0.001, respectively). The percentage of uncovered strut was significantly smaller in EES-treated lesions than in SES-treated lesions (4.4 ± 4.7% vs. 10.5 ± 12.7%, P = 0.016, respectively). There was no significant difference in the percentage of malapposed strut between the two groups (0.4 ± 0.8% in EES vs. 1.7 ± 4.5% in SES, P = 0.344). The incidence of intracoronary thrombus was significantly lower in EES-treated lesions than in SES-treated lesions (5.0% vs. 34.3%, P < 0.001, respectively). EES showed a significantly lower incidence of uncovered stent struts and intracoronary thrombus than SES in 9-month follow-up OCT examination. Compared to SES, EES might have more favorable vascular responses after stent implantation.

Topics: Aged; Angioplasty, Balloon, Coronary; Cardiovascular Agents; Chi-Square Distribution; Coronary Angiography; Coronary Artery Disease; Coronary Restenosis; Coronary Thrombosis; Coronary Vessels; Drug-Eluting Stents; Everolimus; Female; Humans; Hyperplasia; Male; Middle Aged; Neointima; Predictive Value of Tests; Registries; Republic of Korea; Retrospective Studies; Sirolimus; Time Factors; Tomography, Optical Coherence; Treatment Outcome

To quantify with in vivo OCT and histology, the device/vessel interaction after implantation of the bioresorbable vascular scaffold (BVS). We evaluated the area and thickness of the strut voids previously occupied by the polymeric struts, and the neointimal hyperplasia (NIH) area covering the endoluminal surface of the strut voids (NIH(EV)), as well as the NIH area occupying the space between the strut voids (NIH(BV)), in healthy porcine coronary arteries at 2, 3 and 4 years after implantation of the device. Twenty-two polymeric BVS were implanted in the coronary arteries of 11 healthy Yucatan minipigs that underwent OCT at 2, 3 and 4 years after implantation, immediately followed by euthanasia. The areas and thicknesses of 60 corresponding strut voids previously occupied by the polymeric struts and the size of 60 corresponding NIH(EV) and 49 NIH(BV) were evaluated with both OCT and histology by 2 independent observers, using a single quantitative analysis software for both techniques. At 3 and 4 years after implantation, the strut voids were no longer detectable by OCT or histology due to complete polymer resorption. However, analysis performed at 2 years still provided clear delineation of these structures, by both techniques. The median [ranges] areas of these strut voids were 0.04 [0.03-0.16] and 0.02 [0.01-0.07] mm(2) by histology and OCT, respectively. The mean (±SD) thickness by histology and OCT was 220 ± 40 and 120 ± 20 μm, respectively. The median [ranges] NIH(EV) by histology and OCT was 0.07 [0.04-0.20] and 0.03 [0.01-0.08] mm(2), while the mean (±SD) NIH(BV) by histology and OCT was 0.13 ± 0.07 and 0.10 ± 0.06 mm(2). Our study indicates that in vivo OCT of the BVS provides correlated measurements of the same order of magnitude as histomorphometry, and is reproducible for the evaluation of certain vascular and device-related characteristics. However, histology systematically gives larger values for all the measured structures compared to OCT, at 2 years post implantation.

Topics: Absorbable Implants; Angioplasty, Balloon, Coronary; Animals; Cardiovascular Agents; Coronary Vessels; Everolimus; Feasibility Studies; Hyperplasia; Models, Animal; Neointima; Pilot Projects; Sirolimus; Swine; Swine, Miniature; Time Factors; Tissue Scaffolds; Tomography, Optical Coherence

Previous optical coherence tomography (OCT) studies in patients with drug-eluting stents (DESs)-related very late stent thrombosis (VLST) were scarce. Therefore, we investigated OCT findings of VLST after implantation of DESs. Using OCT, we analyzed the status of stent struts and neointimal characteristics in 18 patients who developed VLST after DES implantation. These results were compared to those in 57 patients with neointimal hyperplasia causing >40% diameter stenosis. Lipid-laden neointima was defined as a region with marked signal attenuation and a diffuse border. Four (22.2%) of 18 patients with VLST had ruptured and lipid-laden neointima inside DESs without uncovered or malapposed stent struts. In the remaining 14 patients who developed VLST without neointimal rupture, uncovered and malapposed struts were observed in nine and seven patients, respectively, and lipid-laden neointima in four patients. Lipid-laden neointima was more frequently observed in four patients with neointimal rupture than in 14 patients without neointimal rupture (100% vs. 28.6%, respectively, P = 0.023). Of 57 patients with neointimal hyperplasia, eight (14.0%) had lipid-laden neointima. Time to OCT study after DES implantation was significantly longer in the eight patients with lipid-laden neointima than in 49 patients without lipid-laden neointima (45.5 ± 17.7 months vs. 11.7 ± 7.2 months, respectively, P < 0.001). Lipid-laden neointima was detected in some patients with neointimal hyperplasia > 1 year after DES implantation. In addition to uncovered or malapposed struts, rupture of lipid-laden neointima inside DESs was identified in some patients with DES-related VLST.

Topics: Adult; Aged; Angioplasty, Balloon, Coronary; Cardiovascular Agents; Chi-Square Distribution; Coronary Angiography; Coronary Artery Disease; Coronary Thrombosis; Coronary Vessels; Drug-Eluting Stents; Everolimus; Female; Humans; Hyperplasia; Lipid Metabolism; Male; Middle Aged; Neointima; Paclitaxel; Predictive Value of Tests; Prosthesis Design; Republic of Korea; Risk Assessment; Risk Factors; Sirolimus; Time Factors; Tomography, Optical Coherence; Treatment Outcome

To evaluate the effect of a polymer-free Biolimus A9-eluting stent [BioFreedom (BF)], compared with that of a biodegradable polymer-based Biolimus A9-eluting stent [BioMatrix Flex (BMF)] and a bare metal stent (BMS) in balloon denuded and radiated hypercholesterolemic rabbit iliac arteries.. Rabbits were fed with 1% cholesterol diet (n = 14) for 14 days, both iliac arteries were balloon denuded and radiated, and then rabbits were switched to 0.15% cholesterol diet. After 4 weeks, BF (n = 8), BMF (n = 8), and BMS (n = 8) were deployed in denuded and radiated areas. Four weeks later animals were euthanized, arterial segments were processed for morphometry.. The neointimal area in vessels implanted with BF stents was significantly less than that seen in vessels implanted with BMS (0.90 mm(2) ± 0.14 vs. 1.29 mm(2) ± 0.23, P <0.01). Percent fibrin and fibrin score were higher with BMF stents compared to BMS (P <0.03 and <0.04) and giant cell number was significantly higher with both BMF and BF stents (P < 0.01 for both). Percent endothelialization was significantly higher and % uncovered struts were lower with BMS compared to either BMF or BF stents (P < 0.05 for both).. This study demonstrates that compared to BMS, BF stents significantly decreased neointimal hyperplasia.

Topics: Absorbable Implants; Angioplasty, Balloon; Animals; Atherosclerosis; Cardiovascular Agents; Constriction, Pathologic; Disease Models, Animal; Drug-Eluting Stents; Fibrin; Hypercholesterolemia; Hyperplasia; Iliac Artery; Inflammation; Male; Metals; Neointima; Plaque, Atherosclerotic; Polymers; Prosthesis Design; Rabbits; Sirolimus; Stents; Time Factors

The authors investigate whether the combination of anti-CD34 antibody with DES is win-win cooperation.. DES may reduce the risk of restenosis compared to bare-metal stents (BMS), but they were found to inhibit the healing process of intima.. Fifteen BMS, 17 DES, and 16 combined anti-CD34 antibody and DES were randomly implanted in the coronary arteries of 22 minipigs. Ten minipigs were followed up to 2 weeks. The stenting coronary segments were examined by histological examination and scanning electron microscopy after in vivo coronary angiography and intracoronary optical coherence tomography (OCT) examinations. The other 12 minipigs were followed up to 3 months. Coronary angiography and intracoronary OCT examination were performed in vivo and histological examination was performed on the stenting coronary segments.. After 2 weeks, the neointimal covering level of the DES was lower than that in BMS, but the covering level of the combined stents was even better than the BMS. After 3 months, neointimal hyperplasia was significant in the BMS, but not in the other two types of stents. The in-stent late lumen loss of the combined stents even showed a decreasing tendency when compared with the DES.. The combination of anti-CD34 antibody and DES can not only well offset the short-term inhibitory effect on re-endothelialization but also slightly enhance the long-term antiproliferative effect.

Topics: Angioplasty, Balloon, Coronary; Animals; Antibodies; Antigens, CD34; Cardiovascular Agents; Cell Proliferation; Coronary Angiography; Coronary Restenosis; Coronary Vessels; Drug-Eluting Stents; Hyperplasia; Metals; Microscopy, Electron, Scanning; Neointima; Prosthesis Design; Sirolimus; Stents; Swine; Swine, Miniature; Time Factors; Tomography, Optical Coherence

Paclitaxel coating of hemodialysis grafts is effective in suppressing neointimal hyperplasia in the graft and vascular anastomosis sites. However, paclitaxel can have unwanted effects on the surrounding tissues. To reduce such problems, we developed a method to coat the drug only on the luminal surface of the graft, with little loading on the outer surface.. A peristaltic pump and a double-solvent (water and acetone) system were used to achieve an inner coating of paclitaxel. At the ratio of 90% acetone, paclitaxel was homogeneously coated only on the luminal surface of the graft without changing the physical properties. To determine its effect, grafts were implanted between the common carotid artery and the external jugular vein in pigs using uncoated control grafts (n = 6) and low-dose (n = 6, 0.22 μg/mm(2)) and high-dose (n = 6, 0.69 μg/mm(2)) paclitaxel inner-coated grafts. Cross-sections of graft-venous anastomoses were analyzed histomorphometrically 6 weeks after placement to measure the patency rate, percentage of luminal stenosis, and neointimal area.. No signs of infection or bacterial contamination were observed in the paclitaxel inner-coated groups. Only one of the six control grafts was patent, but all of the paclitaxel-coated grafts were patent, with little neointima. The mean ± standard error values of percentage luminal stenosis were 75.7% ± 12.7% (control), 17.5% ± 3.1% (low dose), and 19.7% ± 3.0% (high dose). The values for the neointimal area (in mm(2)) were 8.77 ± 1.66 (control), 3.53 ± 0.73 (lose dose), and 4.24 ± 0.99 (high dose). Compared with the control group, paclitaxel inner-coated vascular grafts significantly suppressed neointimal hyperplasia (low dose, P = .001; high dose, P = .002). Myofibroblast proliferation and migration into the graft interstices confirmed the firm attachment of the implanted graft to the surrounding tissue.. Paclitaxel coating on the inner luminal surface of vascular grafts was effective in suppressing neointimal hyperplasia, with little inhibition of myofibroblast infiltration within the graft wall.

Topics: Animals; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Cardiovascular Agents; Carotid Artery, Common; Cell Movement; Cell Proliferation; Coated Materials, Biocompatible; Drug Carriers; Female; Graft Occlusion, Vascular; Hyperplasia; Jugular Veins; Myofibroblasts; Paclitaxel; Prosthesis Design; Renal Dialysis; Solubility; Swine; Time Factors; Tunica Intima; Vascular Patency

Arterialized vein grafts often fail due to intimal hyperplasia. Hydrogen potently protects organs and cells from many insults via its anti-inflammatory and antioxidant properties. We investigated the efficacy of oral administration of hydrogen-rich water (HW) for prevention of intimal hyperplasia.. The inferior vena cava was excised, stored in cold Ringer solution for 2 h, and placed as an interposition graft in the abdominal aorta of syngeneic Lewis rats. HW was generated by immersing a magnesium stick in tap water (Mg + 2H(2)O → Mg (OH)(2) + H(2)). Beginning on the day of graft implantation, recipients were given tap water [regular water (RW)], HW or HW that had been subsequently degassed water (DW). Six weeks after grafting, the grafts in the rats given RW or DW had developed intimal hyperplasia, accompanied by increased oxidative injury. HW significantly suppressed intimal hyperplasia. One week after grafting, the grafts in HW-treated rats exhibited improved endothelial integrity with less platelet and white blood cell aggregation. Up-regulation of the mRNAs for intracellular adhesion molecules was attenuated in the vein grafts of the rats receiving HW. Activation of p38 mitogen-activated protein kinase, matrix metalloproteinase (MMP)-2, and MMP-9 was also significantly inhibited in grafts receiving HW. In rat smooth muscle cell (A7r5) cultures, hydrogen treatment for 24 h reduced smooth muscle cell migration.. Drinking HW significantly reduced neointima formation after vein grafting in rats. Drinking HW may have therapeutic value as a novel therapy for intimal hyperplasia and could easily be incorporated into daily life.

Topics: Administration, Oral; Animals; Anti-Inflammatory Agents; Antioxidants; Aorta, Abdominal; Cardiovascular Agents; Cell Movement; Cell Proliferation; Cells, Cultured; Disease Models, Animal; Drinking; Endothelial Cells; Enzyme Activation; Humans; Hydrogen; Hyperplasia; Interleukin-6; Macrophages; Male; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Neointima; Oxidative Stress; p38 Mitogen-Activated Protein Kinases; Phosphorylation; Rats; Rats, Inbred Lew; Time Factors; Transplantation, Isogeneic; Tumor Necrosis Factor-alpha; Tunica Intima; Vascular Grafting; Vena Cava, Inferior

Despite rapid progress in surgical techniques, there is still a significant lack of surgery-supportive pharmacological treatments. The aim of this study was to test the hypothesis that ursolic acid (UA) may prevent intimal hyperplasia of venous bypass grafts.. The hypothesis was tested by means of primary cell isolation and culture followed by real-time polymerase chain reaction, western blotting, fluorescence microscopy and fluorescence-activated cell sorting analyses, as well as an in vivo rat model for intimal hyperplasia of venous bypass grafts and immunohistochemistry and histochemistry.. The local application of UA significantly inhibited intimal hyperplasia in vivo (intimal thickness control: 25 µm, UA group: 18 µM-8 weeks after surgery). The UA treatment of grafts significantly resulted in reduced endothelial vascular cell adhesion molecule-1 (VCAM-1) expression, reduced infiltration of the grafts vessel wall by CD45-positive cells and increased smooth muscle cell (SMC) death. In in vitro condition, it could be shown that UA inhibits VCAM-1 expression downstream of NFκB and is likely to interfere with VCAM-1 protein synthesis in endothelial cells. Quantification of cell death in vascular smooth muscle cells treated with UA indicated that UA is a potent inducer of SMC apoptosis.. Our results suggest that UA-mediated inhibition of endothelial VCAM-1 expression reduces the infiltration of venous bypass grafts by CD45-positive cells and inhibits intimal hyperplasia. Apoptosis induction in SMCs may be another method in which UA reduces intimal thickening. UA may constitute a surgery-supportive pharmacon that reduces intimal hyperplasia of vein grafts.

Topics: Animals; Apoptosis; Biomarkers; Blotting, Western; Cardiovascular Agents; Cell Survival; Flow Cytometry; Graft Occlusion, Vascular; Hyperplasia; Jugular Veins; Leukocyte Common Antigens; Male; Microscopy, Fluorescence; Rats; Rats, Wistar; Real-Time Polymerase Chain Reaction; Treatment Outcome; Triterpenes; Tunica Intima; Ursolic Acid; Vascular Cell Adhesion Molecule-1; Vascular Grafting

Delayed endothelialization contributes to stent thrombosis of current drug-eluting stents. The asymmetrical coating technique provides an anti-proliferative effect abluminally without affecting luminal endothelialization. Layer-by-layer self-assembled chitosan/heparin (C/H LBL) has been proved to promote re-endothelialization. A novel stent system, C/H LBL coated luminally and sirolimus released abluminally (C/H LBL-SES), was fabricated.. Bare metal stents (BMS), traditionally circumferential sirolimus-eluting stents (SES), and C/H LBL-SES were implanted into porcine coronary arteries. At the 7, 14 and 28 days follow-up (FU), angiography, intravascular ultrasound (IVUS), vasomotor function induced by acetylcholine (Ach), scanning-electron microscopy and histopathology were performed. Remodeling index (RI) was based on IVUS and defined as cross-sectional area (CSA) of vessel at in-stent segment divided by CSA of reference vessel and expressed as a percentage with a normal range from 0.95 to 1.05.. Thirty-eight mini pigs were enrolled and 74 stents (BMS = 23, C/H LBL = 28, SES = 23) were implanted in this study. At 28 days after implantation, the diameter stenosis of C/H LBL-SES by quantitative coronary angiography was 18.8 ± 2.5 %, the area stenosis by histomorphometry was 24.2 ± 2.9 %, which were comparable to that of SES and superior to BMS. At 14 days, re-endothelialization of C/H LBL-SES was almost completed, while only about 50 % of surface of SES was covered by endothelium. At 7, 14 and 28 days FU, although C/H LBL-SES suffered a greater vasoconstriction induced by Ach infusion than BMS (P < 0.05), it behaved better than SES (P < 0.01). No sign of stent malapposition was detected, while RI was within the normal range by IVUS. No acute or subacute thrombotic events occurred in all three groups.. The asymmetrically designed C/H LBL-SES successfully inhibited neointima hyperplasia, while diminishing vasoconstriction after Ach-stress. Endothelialization of C/H LBL-SES was less affected compared with traditionally circumferentially coated SES.

Topics: Acetylcholine; Animals; Cardiovascular Agents; Chitosan; Coated Materials, Biocompatible; Coronary Angiography; Coronary Restenosis; Coronary Vessels; Disease Models, Animal; Drug-Eluting Stents; Endothelial Cells; Heparin; Hyperplasia; Metals; Microscopy, Electron, Scanning; Neointima; Percutaneous Coronary Intervention; Prosthesis Design; Sirolimus; Swine; Swine, Miniature; Time Factors; Ultrasonography, Interventional; Vasoconstriction

High mobility group box 1 protein (HMGB1) is expressed in atherosclerotic lesions. However, its role in vascular system is unknown. In this study, we explore whether the inhibition of HMGB1 attenuates neointimal formation in animal models.. Experiments were performed with VSMCs from thoracic aorta of SD rats in vitro, and a rat carotid artery balloon injury model in vivo. HMGB1 levels were increased after stimulation of angiotensin II (Ang II) and 10% serum in cultured VSMCs. HMGB1 inhibitor (glycyrrhizin) significantly inhibited the proliferation and migration of Ang II-treated VSMCs, which was accompanied with decreased oxidative stress and inflammation. The underlying mechanisms were related with the promotion of antioxidant systems activity and deactivation of p38 MAPK/NF-κB signaling pathway, respectively. Furthermore, inhibition of HMGB1 blunted Notch signaling pathway during VSMCs phenotypic transition, and correspondingly restored VSMCs differentiated phenotype under 10% serum stimulation. In vivo study, HMGB1 expression was elevated after artery injury. Meanwhile, glycyrrhizin treatment suppressed HMGB1 expression, which was accompanied with blunted inflammation and oxidative stress after 7 days of balloon injury. Moreover, the area of neointimal to media area ratio was significantly decreased in glycyrrhizin group compared with injury group at 14 days after balloon injury.. Inhibition of HMGB1 activity attenuated VSMCs activation and neointimal formation after carotid injury. Therefore, blockage of HMGB1 might represent a novel therapeutic strategy for vascular injury.

Topics: Angiotensin II; Animals; Anti-Inflammatory Agents; Antioxidants; Cardiovascular Agents; Carotid Arteries; Carotid Artery Injuries; Cell Differentiation; Cell Movement; Cell Proliferation; Cells, Cultured; Disease Models, Animal; Dose-Response Relationship, Drug; Glycyrrhizic Acid; HMGB1 Protein; Hyperplasia; Inflammation Mediators; Male; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Neointima; NF-kappa B; Oxidative Stress; p38 Mitogen-Activated Protein Kinases; Phenotype; Rats; Rats, Sprague-Dawley; Receptors, Notch; Signal Transduction; Time Factors

Topics: Angina, Unstable; Cardiovascular Agents; Coronary Angiography; Coronary Thrombosis; Coronary Vessels; Drug-Eluting Stents; Humans; Hyperplasia; Male; Middle Aged; Neointima; Percutaneous Coronary Intervention; Predictive Value of Tests; Prosthesis Design; Sirolimus; Thrombectomy; Time Factors; Tomography, Optical Coherence; Treatment Outcome

Despite the expressive reduction in the intimal hyperplasia (IH) formation after DES implantation at the mid-term, late restenosis has been recently noticed. Our objective was to determine, by means of serial angiography (QCA) and intravascular ultrasound (IVUS) at two different time points, whether the occurrence of the "late catch-up" phenomenon occurs after sirolimus-eluting stent (SES) implantation. Thirty-eight non-complex patients treated with a single 18-mm SES who had systematic serial QCA and IVUS analyses at mean 8 and 20 months were enrolled. Primary endpoint is to evaluate the temporal course of IH formation after SES implantation, by comparing QCA in-stent late loss and IVUS percent IH obstruction between the invasive follow-ups. Mean cohort age was 59.3 years and 31.6% were diabetics. Baseline reference vessel diameter was 2.8 ± 0.4 mm and lesion length was 11.5 ± 3.5 mm. Left anterior descending artery was the most frequent target vessel (55.3%). Between 8 and 20 months, a non-significant increase in in-stent late loss from 0.10 ± 0.18 to 0.15 ± 0.30 mm (P = 0.38) was observed. By IVUS, a slight increase in the percent IH obstruction (1.03 ± 2.13 to 1.76 ± 1.87%, P = 0.12) was detected between the two evaluations. Interestingly, all the neoformed tissue accrued from 8 to 20 months accumulated in the distal portion of the stent. In the non-complex scenario, SES implantation was associated with a minimal, non-significant increase in the IH volume between 8 and 20 months.

Topics: Aged; Analysis of Variance; Angioplasty, Balloon, Coronary; Brazil; Cardiovascular Agents; Chi-Square Distribution; Coronary Angiography; Coronary Artery Disease; Coronary Restenosis; Drug-Eluting Stents; Female; Humans; Hyperplasia; Male; Middle Aged; Predictive Value of Tests; Prosthesis Design; Risk Assessment; Risk Factors; Sirolimus; Time Factors; Tomography, X-Ray Computed; Treatment Outcome; Ultrasonography, Interventional

Zoledronate has been reported to inhibit the proliferation, adhesion and migration of vascular smooth muscle cells. In the present study, we assessed whether systemic and local delivery of zoledronate would be sufficient to prevent intimal hyperplasia.. Twenty-four male Sprague-Dawley rats were assigned into four groups: non-treated group, systemic zoledronate-treated group, local collagen-treated group and local zoledronate-treated group. All four groups underwent balloon injury to the right common carotid artery. The left uninjured carotid arteries of the non-treated group were considered as normal artery samples. Twenty-one days after arterial injury and treatment, the right and left common carotid arteries were fixed, sectioned, stained and measured by computer-aided image analysis.. At 3 weeks, there was a 59% reduction of the intima/media area ratio in the systemic zoledronate-treated group compared with the non-treated group (P < 0.01). There was an 87% reduction of the intima/media area ratio in the local zoledronate-treated group compared with the local collagen-treated group (P < 0.01).. Both systemic and local delivery of zoledronate correspond to a significant reduction in intimal hyperplasia seen at 3 weeks.

Topics: Administration, Topical; Angioplasty, Balloon; Animals; Cardiovascular Agents; Carotid Artery Injuries; Carotid Artery, Common; Cell Proliferation; Diphosphonates; Disease Models, Animal; Hyperplasia; Image Processing, Computer-Assisted; Imidazoles; Immunohistochemistry; Injections, Intravenous; Male; Proliferating Cell Nuclear Antigen; Rats; Rats, Sprague-Dawley; Time Factors; Tunica Intima; Zoledronic Acid

Topics: Animals; Arterial Occlusive Diseases; Cardiovascular Agents; Cell Movement; Cell Proliferation; Constriction, Pathologic; Humans; Hyperplasia; Kv1.3 Potassium Channel; Mice; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Potassium Channel Blockers; Recurrence; Tunica Intima

Optical coherence tomography is a high-resolution imaging technology that allows in vivo assessment of neointimal hyperplasia and strut coverage after coronary stenting.. Assessment of spatial distribution of healing, 6 months after zotarolimus-eluting stent implantation.. Forty-two zotarolimus-eluting stents were monitored by optical coherence tomography 6 months after implantation. Mean neointimal strut coverage thickness and percentage of neointimal hyperplasia were measured every millimetre. Non-covered strut ratios were assessed on each slice. In addition, the spatial distribution of neointimal hyperplasia and strut coverage were analysed longitudinally on five stent segments and axially on each slice.. There were no clinical events at 6 months under dual antiplatelet therapy. The optical coherence tomography analysis showed a mean neointimal hyperplasia thickness of 333±147μm and neointimal hyperplasia obstruction of 36.1±12.3%. The percentage of covered struts at 6 months was very high (98.9%). Only 6/745 slices analysed (0.8%) had non-covered strut ratios exceeding 30%. There was no significant heterogeneity in either longitudinal or axial neointimal hyperplasia distribution. No thrombi were observed.. This optical coherence tomography study found relatively constant neointimal hyperplasia thickness, regardless of the zotarolimus-eluting stent length or diameter. This spatially homogeneous neointimal hyperplasia was associated with near-total coverage of all struts, 6 months after implantation.

Topics: Aged; Angioplasty, Balloon, Coronary; Cardiovascular Agents; Coronary Angiography; Coronary Restenosis; Coronary Vessels; Drug Therapy, Combination; Drug-Eluting Stents; Female; France; Humans; Hyperplasia; Male; Middle Aged; Platelet Aggregation Inhibitors; Prospective Studies; Prosthesis Design; Sirolimus; Time Factors; Tomography, Optical Coherence; Treatment Outcome; Tunica Intima

Nanoparticles (NPs) possess several advantages as a carrier system for intracellular delivery of therapeutic agents. Rapamycin is an immunosuppressive agent which also exhibits marked antiproliferative properties. We investigated whether rapamycin-loaded NPs can reduce neointima formation of vein graft disease in a rat model.. Poly(lactic-co-glycolic acid) (PLGA) NPs-containing rapamycin was prepared using an oil/water solvent evaporation technique. The size and morphology of the NP were determined by dynamic light scattering methodology and electron microscopy. In vitro cytotoxicity of blank, rapamycin-loaded PLGA NPs was studied using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. Excised rat jugular vein was treated ex vivo with blank NPs, or rapamycin-loaded NPs, and then interposed back into the carotid artery position using a cuff technique. Grafts were harvested for 21 days and subjected to morphometric analysis as well as immunohistochemical analysis and Western blotting.. Rapamycin was efficiently loaded in PLGA NPs with an encapsulation efficiency of 87.6%. The average diameter of NPs was 180.3 nm. The NPs-containing rapamycin at 1 ng/mL significantly inhibited vascular smooth muscular cells proliferation. Measurement of rapamycin levels in vein grafts showed that the concentration of rapamycin in vein grafts at 3 weeks after grafting was 0.9 ± 0.1 μg/g. In grafted veins without treatment, intima-media thickness was 300.4 ± 181.5 μm at 21 days after grafting, whereas veins treated with rapamycin-loaded NPs showed a reduction of intimal-media thickness of 150.2 ± 62.5 μm (p = 0.001). Cell proliferation was measured by proliferating cell nuclear antigen immunohistochemistry staining. As expected, proliferating cell nuclear antigen index declined from 83.4% ± 7.4% to 66.2% ± 4.5% in vein grafts after 3 weeks (p = 0.002). Platelet endothelial cell adhesion molecule (PECAM-1/CD31) staining was used to measure luminal endothelial coverage in grafts and indicated a high level of endothelialization at 21 days after grafting, with no significant effect of blank or rapamycin-loaded NPs group. Western blot analysis showed that treatment with rapamycin-loaded PLGA NPs markedly attenuated phosphorylation and activation of S6 kinase 1 phosphorylation and inactivation of 4E (eIF4E)-binding protein 1, both in vascular smooth muscular cells and vein grafts at 7 and 21 days after grafting.. We conclude that sustained-release rapamycin from rapamycin-loaded NPs inhibits vein graft thickening without affecting the endothelial cells in rat carotid vein-to-artery interposition grafts; thus, this may be a promising therapy for the treatment of vein graft disease.

Topics: Animals; Blotting, Western; Cardiovascular Agents; Carotid Arteries; Carrier Proteins; Cell Proliferation; Cells, Cultured; Delayed-Action Preparations; Drug Carriers; Endothelial Cells; Graft Survival; Hyperplasia; Immunohistochemistry; Intracellular Signaling Peptides and Proteins; Jugular Veins; Lactic Acid; Light; Male; Microscopy, Electron, Transmission; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Nanoparticles; Phosphoproteins; Phosphorylation; Platelet Endothelial Cell Adhesion Molecule-1; Polyglycolic Acid; Polylactic Acid-Polyglycolic Acid Copolymer; Rats; Rats, Sprague-Dawley; Ribosomal Protein S6 Kinases; Scattering, Radiation; Sirolimus; Solubility; Tunica Intima; Vascular Grafting

To determine the efficacy of sirolimus-eluting bioabsorbable magnesium alloy stents (SEBMAS) in restenosis prevention.. A balloon-expandable bioabsorbable magnesium alloy stent (BMAS) was created and coated with biodegradable poly(lactic acid-co-trimethylene carbonate) that contained the antiproliferative drug sirolimus (140 ± 40 µg/cm²). Both the uncoated BMAS and the coated SEBMAS were deployed 2 cm apart in balloon-injured infrarenal abdominal aortas of 20 New Zealand white rabbits. The stented aortic segments were removed at 30, 60, 90, and 120 days (5 rabbits per interval) after implantation. The average stent strut sectional area of each group was measured to evaluate the degree of magnesium corrosion and to forecast the biodegradation time profile of the magnesium stent. Histology and histopathology of the sectioned stented aortic segments were performed to evaluate neointima formation, endothelialization, and inflammation.. The SEBMAS degraded gradually after being implanted into the rabbit aorta, and total biocorrosion occurred after ~120 days. In all groups, the lumen area was significantly greater, but the neointimal area was significantly smaller in SEBMAS segments compared with the uncoated BMAS segments (p < 0.05) at all time points. There was no significant difference in the injury or inflammation scores between the groups. Endothelialization was delayed at 30 days in the SEBMAS segments vs. the uncoated BMAS segments.. SEBMAS further reduces intimal hyperplasia and improves the lumen area when compared to uncoated BMAS; however, it delays vascular healing and endothelialization.

Topics: Alloys; Angioplasty; Animals; Aorta, Abdominal; Aortic Diseases; Arterial Occlusive Diseases; Cardiovascular Agents; Cell Proliferation; Coated Materials, Biocompatible; Constriction, Pathologic; Dioxanes; Disease Models, Animal; Drug-Eluting Stents; Endothelial Cells; Hyperplasia; Lactic Acid; Magnesium; Male; Polyesters; Polymers; Prosthesis Design; Rabbits; Secondary Prevention; Sirolimus; Time Factors; Wound Healing

Autologous vein grafts used as aortocoronary bypasses are often prone to intimal hyperplasia, which results in stenosis and occlusion of the vein. The aim of this study was to prevent intimal hyperplasia using a newly developed perivascular system with sustained release of sirolimus. This system of controlled drug release consists of a polyester mesh coated with a copolymer of L-lactic acid and epsilon-caprolactone that releases sirolimus. The mesh is intended for wrapping around the vein graft during surgery. The mesh releasing sirolimus was implanted in periadventitial position onto arteria carotis communis of rabbits, and neointimal hyperplasia was then assessed. We found that implanted sirolimus-releasing meshes reduced intima thickness by 47+/-10 % compared to a vein graft after 3 weeks. The pure polyester mesh decreased vein intima thickness by 35+/-9 %. Thus, our periadventitial system for controlled release of sirolimus prevented the development of intimal hyperplasia in autologous vein grafts in vivo in rabbits. A perivascularly applied mesh releasing sirolimus is a promising device for preventing stenosis of autologous vein grafts.

Topics: Animals; Cardiovascular Agents; Cell Proliferation; Drug Carriers; Graft Occlusion, Vascular; Hyperplasia; Jugular Veins; Polyesters; Rabbits; Sirolimus; Tunica Intima

To evaluate the development of neointimal hyperplasia after implantation of drug-eluting stents (paclitaxel) compared to bare metal stents in porcine internal carotid arteries (ICAs).. While drug-eluting stents have effectively reduced neointimal proliferation in porcine external carotid arteries, the porcine internal carotid artery (ICA) is more sensitive to shear stress and altered flow conditions. Thus, a study was conducted to evaluate bare vs. drug-eluting stents in porcine ICAs. Under general anesthesia, 18 domestic pigs were implanted with paclitaxel-eluting (n = 18) and bare (n = 18) stents in the left and right ICAs, respectively. After 1 and 3 months, control carotid angiography was performed, followed by histopathological and histomorphometric analyses of the stented ICA.. Histopathological results (fibrin deposition, necrosis, inflammation) were similar in the groups at 1 and 3 months. Moreover, the injury score and rate of endothelialization did not differ between the groups. Histomorphometric analysis after 1 month revealed significantly (p<0.05) less neointimal hyperplasia after implantation of paclitaxel-eluting stents. The antiproliferative effect of paclitaxel-eluting stents were maintained during the 3-month follow-up: the neointimal area was 0.7 ± 0.5 vs. 1.2 ± 0.6 mm(2) (p<0.01), the area stenosis was 23.5% ± 13.9% vs. 37.8% ± 14.4% (p<0.01), the maximal neointimal thickness was 0.2 ± 0.1 vs. 0.2 ± 0.9 mm (p<0.05) in paclitaxel-eluting vs. bare stents, respectively. Implantation of paclitaxel-eluting and bare stents did not lead to edge restenosis or vessel remodeling in porcine ICAs at 1 or 3 months.. Compared to bare metal stents, drug-eluting stents implanted in the porcine ICA produced significantly less neointimal hyperplasia.

Topics: Angioplasty, Balloon; Animals; Cardiovascular Agents; Carotid Artery, Internal; Carotid Stenosis; Cell Proliferation; Drug-Eluting Stents; Hyperplasia; Metals; Paclitaxel; Platelet Aggregation Inhibitors; Prosthesis Design; Radiography; Stents; Sus scrofa; Time Factors; Tunica Intima

This study aimed to evaluate the impact of angiographic and intravascular ultrasound (IVUS) features on clinical outcome in nondiabetic and type 2 diabetic patients after percutaneous coronary intervention (PCI) with sirolimus-eluting stent (SES) implantation.. Repeat coronary angiography with IVUS imaging was performed after SES-based PCI for de-novo lesions in 128 diabetic and 327 nondiabetic patients (189 lesions and 504 lesions, respectively). The rate of major adverse cardiac events including cardiac death, non fatal myocardial infarction (MI), and target lesion revascularization during clinical follow-up was recorded.. In-stent and in-segment late loss, intimal hyperplasia volume, and percentage volumetric obstruction were similar, but stented external elastic membrane cross-sectional area and reference/stented segment ratio were lower in diabetic than in nondiabetic patients. Incomplete stent apposition (ISA) was less frequent, but occurrence of new coronary lesions was higher in diabetic than in nondiabetic patients. Despite similar target lesion revascularization, cumulative survival rates freedom from composite cardiac death and nonfatal MI or major adverse cardiac events were reduced in diabetic patients. Cox proportional hazards model identified diabetes, left ventricular ejection fraction, minimal stent CSA, maximal ISA area, atherosclerotic progression and lesion length as independent predictors of non fatal MI or mortality at follow-up.. In diabetic patients, PCI with SES implantation neutralizes the excess risk of intimal hyperplasia and decreases occurrence of ISA, but could not modify the propensity of increased adverse clinical outcomes at follow-up.

Topics: Aged; Angioplasty, Balloon, Coronary; Cardiovascular Agents; Chi-Square Distribution; Coronary Angiography; Coronary Artery Disease; Coronary Restenosis; Coronary Vessels; Diabetes Mellitus, Type 2; Drug-Eluting Stents; Female; Heart Diseases; Humans; Hyperplasia; Kaplan-Meier Estimate; Male; Middle Aged; Myocardial Infarction; Predictive Value of Tests; Proportional Hazards Models; Risk Assessment; Risk Factors; Sirolimus; Time Factors; Treatment Outcome; Ultrasonography, Interventional

Perlecan is the major heparan sulfate proteoglycan in the arterial wall. Previous studies have suggested that perlecan is a potent inhibitor of smooth muscle cell (SMC) activity. Therefore, perlecan overexpression may serve as a therapeutic modality to prevent in-stent restenosis (ISR). We have investigated a novel compound (RUS3108), identified in a SMC based screen to induce perlecan synthesis in SMC. The aims of this study were to assess the in vitro effects of RUS3108 and the effects of RUS3108-eluting stents in preventing ISR.. Rabbit aortic SMC and bovine aortic endothelial cells (EC) were used in this study. Immunohistochemistry showed that RUS3108-treated SMC over-expressed perlecan indicating the drug effects. Furthermore, RUS3108 induced a SMC differentiated phenotype by SMembryonic staining. RUS3108 (1 microM) inhibited 3H-thymidine incorporation by >50%, which was completely reversed by a perlecan antibody. RUS3108 also inhibited SMC migration (Boyden chamber) and MMP-9 activity. In contrast, RUS3108 (100nM) modestly stimulated EC 3H-thymidine incorporation by 22% (p<0.02). In vivo, a total of 30 stents were deployed in rabbit iliac arteries as follows: 1) bare metal stents (n=10), 2) polymer onlycoated stents (n=10), and 3) polymer-coated stents containing RUS3108 (n=10). Rabbits were sacrificed at four weeks and stented segments were subjected to morphometric analysis. Intimal cross sectional area was significantly lower in the RUS3108-eluting stent group (0.31+ or -0.27 mm(2) versus 1.0 + or - 0.31 and 1.25 + or - 0.51 in the bare metal stents and polymer only coated stents groups, respectively, p<0.0001).. RUS3108 is a novel perlecan-inducing compound, which is a potent inhibitor of SMC activity and a modest stimulator of EC proliferation. RUS3108-eluting stents may serve as an excellent modality for the prevention of ISR.

Topics: Angioplasty, Balloon; Animals; Cardiovascular Agents; Cattle; Cell Differentiation; Cell Movement; Cell Proliferation; Cells, Cultured; Dose-Response Relationship, Drug; Drug-Eluting Stents; Endothelial Cells; Heparan Sulfate Proteoglycans; Hyperplasia; Iliac Artery; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Rabbits; Time Factors; Tunica Intima; Up-Regulation

To explore whether α-lipoic acid (ALA), a naturally occurring antioxidant, inhibits neointimal hyperplasia by inducing apoptosis of vascular smooth muscle cells and to examine its potential effects on reendothelialization and platelet aggregation.. Restenosis and late stent thrombosis, caused by neointimal hyperplasia and delayed reendothelialization, are significant clinical problems of balloon angioplasty and drug-eluting stents. ALA treatment strongly induced apoptosis of vascular smooth muscle cells and enhanced the expression and cytoplasmic localization of Nur77, which triggers intrinsic apoptotic events. Small interfering RNA-mediated downregulation of Nur77 diminished this proapoptotic effect of ALA. Moreover, ALA increased p38 mitogen-activated protein kinase phosphorylation, and inhibition of p38 mitogen-activated protein kinase completely blocked ALA-induced vascular smooth muscle cell apoptosis and Nur77 induction and cytoplasmic localization. In balloon-injured rat carotid arteries, ALA enhanced Nur77 expression and increased TUNEL-positive apoptotic cells in the neointima, leading to inhibition of neointimal hyperplasia. This preventive effect of ALA was significantly reduced by infection of an adenovirus encoding Nur77 small hairpin (sh)RNA. Furthermore, ALA reduced basal apoptosis of human aortic endothelial cells and accelerated reendothelialization after balloon injury. ALA also suppressed arachidonic acid-induced platelet aggregation.. ALA could be a promising therapeutic agent to prevent restenosis and late stent thrombosis after angioplasty and drug-eluting stent implantation.

Topics: Animals; Apoptosis; Cardiovascular Agents; Disease Models, Animal; Endothelial Cells; Endothelium, Vascular; Hyperplasia; Male; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Nuclear Receptor Subfamily 4, Group A, Member 1; p38 Mitogen-Activated Protein Kinases; Platelet Aggregation; Rats; Thioctic Acid; Wound Healing

The aim of this preclinical study was to optimize the use of drug-eluting balloon (DEB) DIOR(2nd) (generation) by measurements of tissue and plasma paclitaxel concentrations in porcine coronary artery overstretch and prove efficacy in inhibition of neointimal growth without complementary use of stent.. The usually recommended DEB 60 sec inflation time causes prolonged ischemia and arterial injury.. Tissue, plasma, and balloon surface concentrations of paclitaxel were measured in pigs 45 min and 12 hr after balloon inflation times of 15, 20, 30, 45, and 60 sec. Extent of neointimal hyperplasia was compared using DIOR(2nd) (generation) or noncoated balloon at two-week follow-up. Paclitaxel was replaced by fluorescent paclitaxel derivative in DEB and DES to demonstrate the distribution of the drug in arterial wall.. DIOR(2nd) (generation) DEB provided 29 ± 3 μM/L, 52 ± 6 μM/L, 196 ± 44 μM/L, 202 ± 36 μM/L, and 184 ± 59 μM/L paclitaxel to the vessel wall after 15, 20, 30, 45, and 60 sec of dilation, reaching plateau at 30 sec inflation time. Paclitaxel penetrated up to 2 mm tissue deepness. Measurable plasma paclitaxel level (45 ± 28 ng/mL) was found only after 60 sec balloon inflation time. At follow-up, the dilated arterial segment neointimal area and maximal neointimal thickness were significantly smaller with DIOR vs. uncoated balloon use. Fluorescence images of DIOR showed a homogenous distribution of the drug on the vessel, in contrast with DES.. Using the DIOR(2nd) (generation) DEB, a maximal balloon inflation time of 30-45 sec is optimal, reducing effectively the neointimal hyperplasia.

Topics: Angioplasty, Balloon, Coronary; Animals; Cardiovascular Agents; Cell Proliferation; Coronary Vessels; Equipment Design; Hyperplasia; Materials Testing; Microscopy, Fluorescence; Models, Animal; Paclitaxel; Sus scrofa; Tissue Distribution; Tunica Intima

The ZoMaxx I and II trials were randomized controlled studies of the zotarolimus-eluting, phosphorylcholine-coated, TriMaxx stent for the treatment of de novo coronary lesions. The aim of this study was to compare the vessel response between zotarolimus- (ZES) and paclitaxel-eluting stents (PES) using intravascular ultrasound (IVUS).. Data were obtained from the ZoMaxx I and II trials, in which a standard IVUS parameter was available in 263 cases (baseline and 9-months follow up). Neointima-free frame ratio was calculated as the number of frames without IVUS-detectable neointima divided by the total number of frames within the stent. While an increase in vessel and plaque was observed in PES from baseline to follow up, there was no significant change in ZES. At follow up, % neointimal obstruction was significantly higher (15.4 ± 8.8% vs 11.3 ± 9.7%), and minimum lumen area at follow up was significantly smaller in ZES compared to PES. However, the incidence of IVUS-defined restenosis (maximum cross-sectional narrowing >60%) was similar in the 2 groups (3.2% vs 6.7%). Neointima-free frame ratio was significantly lower in ZES. There were 5 cases of late incomplete stent apposition in PES and none in ZES.. These IVUS results demonstrate a similar incidence of severe narrowing between these 2 DES. There was a moderate increase in neointimal hyperplasia that was associated with a greater extent of neointimal coverage in ZES compared with PES.

Topics: Aged; Angioplasty, Balloon, Coronary; Cardiovascular Agents; Chi-Square Distribution; Coronary Angiography; Coronary Restenosis; Coronary Vessels; Drug-Eluting Stents; Female; Humans; Hyperplasia; Male; Middle Aged; Multicenter Studies as Topic; Paclitaxel; Prosthesis Design; Randomized Controlled Trials as Topic; Risk Assessment; Risk Factors; Sirolimus; Time Factors; Treatment Outcome; Tunica Intima; Ultrasonography, Interventional

Topics: Angioplasty, Balloon, Coronary; Cardiovascular Agents; Coronary Restenosis; Endothelial Cells; Erythropoietin; Humans; Hyperplasia; Myocardial Infarction; Myocardium; Recombinant Proteins; Stroke Volume; Time Factors; Treatment Outcome; Ventricular Function, Left; Ventricular Remodeling

Neointima formation participates in the pathophysiology of atherosclerosis and restenosis. Proliferation and migration of vascular smooth muscle cells (VSMC) are initial responses to vascular injury. The aim of the present study was to assess the effect of gliotoxin, an inhibitor of nuclear factor (NF)-kappaB, on migration and proliferation of cultured rat VSMC and neointimal formation in injured rat vessels. In cultured VSMC, gliotoxin inhibited the nuclear translocation of the p65 subunit of NF-kappaB in response to inflammatory stimuli. In addition, gliotoxin inhibited VSMC migration and proliferation in response to platelet-derived growth factor-BB. This was associated with a rapid rearrangement of the F-actin and vimentin cytoskeleton. Furthermore, gliotoxin inhibited endothelial cell nuclear translocation of p65, cell surface expression of adhesion molecules such as VCAM-1, ICAM-1 and E-selectin, and monocytic cell adhesion to a cytokine-activated endothelial monolayer. In the rat carotid artery balloon catheter injury model, the systemic administration of gliotoxin for 10 days decreased neointimal hyperplasia and luminal stenosis by up to 90% and decreased the expression of proliferating cell nuclear antigen in the vessel wall by up to 70%, depending on the dose. These observations suggest that gliotoxin favorably regulates the response to vascular injury through actions on VSMC. However, further studies evaluating the therapeutic benefit of gliotoxin in restenosis after balloon angioplasty are required.

Topics: Actins; Active Transport, Cell Nucleus; Angioplasty, Balloon; Animals; Becaplermin; Cardiovascular Agents; Carotid Artery Injuries; Cell Adhesion; Cell Adhesion Molecules; Cell Movement; Cell Proliferation; Cells, Cultured; Disease Models, Animal; Endothelium, Vascular; Gliotoxin; Hyperplasia; Male; Monocytes; Muscle, Smooth, Vascular; Platelet-Derived Growth Factor; Proliferating Cell Nuclear Antigen; Proto-Oncogene Proteins c-sis; Rats; Rats, Sprague-Dawley; Recurrence; Time Factors; Transcription Factor RelA; Vimentin

Atherosclerosis, restenosis, and posttransplant graft atherosclerosis are characterized by endothelial damage, infiltration of inflammatory cells, and proliferation of smooth muscle cells. The CXCR3-activating chemokines interferon-gamma inducible protein 10 (IP10) and MIG (monokine induced by interferon-gamma) have been implicated in vascular repair and remodeling. The underlying molecular mechanisms, however, remain elusive. Here, we show that wire-mediated arterial injury induced local and systemic expression of IP10 and MIG, resulting in enhanced recruitment of CXCR3(+) leukocytes and hematopoietic progenitor cells. This was accompanied by profound activation of mammalian target of rapamycin complex (mTORC)1, increased reactive oxygen species production, apoptosis, and intimal hyperplasia. Genetic and pharmacological inactivation of CXCR3 signaling not only suppressed recruitment of inflammatory cells but also abolished mTORC1 activation, reduced reactive oxygen species generation, and blocked apoptosis of vascular cells, resulting in significant reduction of intimal hyperplasia in vivo. In vitro, stimulation of T cells with IP10 directly activated mTORC1 and induced generation of reactive oxygen species and apoptosis in an mTORC1-dependent manner. These results strongly indicate that CXCR3-dependent activation of mTORC1 directly links stimulation of the Th1 immune system with the proliferative response of intimal cells in vascular remodeling.

Topics: Animals; Apoptosis; Cardiovascular Agents; Carrier Proteins; Cell Proliferation; Chemokine CXCL10; Chemokine CXCL9; Chemotaxis; Disease Models, Animal; Everolimus; Femoral Artery; Hematopoietic Stem Cells; Humans; Hyperplasia; Inflammation; Jurkat Cells; Mice; Mice, Inbred BALB C; Mice, Knockout; Phosphotransferases (Alcohol Group Acceptor); Reactive Oxygen Species; Receptors, CXCR3; Signal Transduction; Sirolimus; Th1 Cells; Time Factors; TOR Serine-Threonine Kinases

Pulmonary venous obstruction (PVO) after correction of total anomalous pulmonary venous connection (TAPVC) frequently occurs due to intimal-hyperplasia and the required re-operation. We have developed a novel sustained-release drug delivery system, using Tacrolimus-eluting biodegradable nano-fiber (TEBN). It consists of nano-scale fiber composed of biodegradable polymer and Tacrolimus. This study evaluated the effects of TEBN for prevention of venous anastomotic stricture in a rat model to apply to PVO operation. Tacrolimus was incorporated into poly (L-lactide-co-glycolide). The venous stricture model was made by rat inferior vena cava anastomosis. The IVC anastomosis was covered with TEBN with 1.0 wt% Tacrolimus (n=12) or without TEBN as a control (n=12), and evaluated histologically at 1, 2, and 4 weeks after operation. The ratio of intimal area was significantly reduced in the TEBN group compared with the control group (ratio; 1 week: 0.43+/-0.26 vs. 0.07+/-0.04, P=0.04, 2 weeks: 0.39+/-0.19 vs. 0.05+/-0.02, P=0.01, 4 weeks: 0.31+/-0.15 vs. 0.09+/-0.04, P=0.03, control vs. TEBN, respectively). Histological findings showed endothelialization along the inner surface of the vein even in TEBN. The TEBN reduced intimal hyperplasia and preserved endothelialization even in a venous stricture. These results suggested that this strategy might be useful for prevention of recurrent PVO after TAPVC correction.

Topics: Absorbable Implants; Anastomosis, Surgical; Animals; Cardiovascular Agents; Cell Proliferation; Disease Models, Animal; Dose-Response Relationship, Drug; Drug-Eluting Stents; Humans; Hyperplasia; Male; Materials Testing; Muscle, Smooth, Vascular; Nanostructures; Polyglactin 910; Prosthesis Design; Pulmonary Veno-Occlusive Disease; Rats; Rats, Wistar; Tacrolimus; Time Factors; Tunica Intima; Vena Cava, Inferior

Restenosis still occurs, even with the sirolimus-eluting stent (SES), and the precise mechanisms have not yet been elucidated. In the present case, focal in-stent stenosis was discovered on angiography 16 months after SES implantation. Intravascular ultrasound revealed an echolucent homogeneous zone, which has been termed "black hole". A sample of stenotic tissue retrieved by aspiration revealed neointimal hyperplasia, composed of proteoglycans and smooth muscle cells with scanty cellularity. Furthermore, infiltration of many macrophages and T lymphocytes coexisted in the restenotic tissue. These findings suggest that delayed healing is 1 of the mechanisms of SES restenosis.

Topics: Aged; Angioplasty, Balloon, Coronary; Biopsy, Needle; Cardiovascular Agents; Coronary Angiography; Coronary Restenosis; Drug-Eluting Stents; Humans; Hyperplasia; Macrophages; Male; Sirolimus; T-Lymphocytes; Tunica Intima; Ultrasonography, Interventional

Long lesions and complex vessel anatomy frequently require the use of overlapping stents to treat a lesion. The purpose of this study was to evaluate the long-term effects of overlapping the Axxess Biolimus A9 eluting stent (BES) with two of the most commonly used, commercially available drug eluting stents. These stents were compared to BxVelocity bare metal (BMS) stents in a porcine coronary stent-injury model.. Nineteen juvenile farm swine, 25-35 kg in weight, 3-6 months in age were utilised. Each animal received an Axxess stent to their coronary artery as permitted by the individual animal's anatomy. A second stent, either a Cypher, sirolimus eluting stent (SES) or, a Taxus, paclitaxel eluting stent (PES), or a BxVelocity bare metal stent (BMS) were implanted in an overlapped fashion. The animals were then followed for either 28 or 180 days as specified by a randomisation scheme. At the end of each follow-up period, they were euthenised, and the vessels containing the overlapping stents were harvested, processed into histological sections, and analysed. Compared to bare metal stents, overlapped segments using DES exhibited delayed vascular healing compared to both the proximal and distal non-overlap sites at each of the follow-up time point. Overall, in the non-overlap stent segments, SES induced significantly more inflammation and neointimal hyperplasia compared to PES and BMS.. In this study of BMS and two different types of DES overlapped with the Axxess Biolimus A9 eluting stent, we found that while there was a delay in the degree of vascular healing with DES compared to BMS, the specific type of DES that was overlapped with BES did not affect the behaviour of the overlap zone in terms of most of the histomorphometric measures at 28 or 180 days. This was true whether the stent was drug eluting or bare metal. More inflammation with delayed healing was seen in the SES compared to PES and BMS.

Topics: Angioplasty, Balloon, Coronary; Animals; Cardiovascular Agents; Cell Proliferation; Coronary Angiography; Coronary Vessels; Drug-Eluting Stents; Hyperplasia; Inflammation; Models, Animal; Nickel; Paclitaxel; Platelet Aggregation Inhibitors; Prosthesis Design; Sirolimus; Stents; Swine; Time Factors; Titanium; Wound Healing

Topics: Animals; Cardiovascular Agents; Carotid Stenosis; Cell Proliferation; Coronary Restenosis; Drug-Eluting Stents; Enzyme Activation; Enzyme Activators; Humans; Hyperplasia; Muscle, Smooth, Vascular; NAD(P)H Dehydrogenase (Quinone); Naphthoquinones; Secondary Prevention; Tunica Intima

The aim of this study was to compare efficacy of low- and high-dose sirolimus release (25, 40, or 100 microg) from hydroxyapatite (HAp) with Cypher (Cordis, Johnson & Johnson, Warren, New Jersey) (111 microg sirolimus) in porcine coronary arteries.. Polymer-based sirolimus-eluting stents such as Cypher interfere with vascular healing, probably due to the permanent presence of the polymer coating and the high sirolimus dose. The use of low-dose sirolimus and inert nonpolymeric but biodegradable coatings such as HAp might be more appropriate.. Stents (n = 68) were implanted, guided by quantitative coronary angiography. All swine received clopidogrel and acetylsalicylic acid during 28 days follow-up. Safety of the coating in absence of drugs was studied by comparing HAp with and without a lipid-based release regulating layer (HApR) with bare-metal stents. Efficacy was studied by comparing the release of 25, 40, and 100 microg sirolimus with Cypher.. The safety study (without drug) revealed no differences in neointimal thickening in response to HAp and HApR with complete healing in all groups. Dose response analysis showed that neointimal thickening was similar in all groups regardless of sirolimus dose, with a normal appearance of the endothelium. There was, however, a dose-dependent increase in fibrinoid (p = 0.028), considered to be a marker of delayed healing. The Cypher stent induced the highest amount of fibrinoid.. Reducing the dose of sirolimus eluting from a biocompatible HAp coated stent reduces signs of delayed vascular healing, without affecting neointimal hyperplasia.

Topics: Angioplasty, Balloon, Coronary; Animals; Aspirin; Cardiovascular Agents; Clopidogrel; Coated Materials, Biocompatible; Coronary Angiography; Coronary Restenosis; Coronary Vessels; Drug-Eluting Stents; Durapatite; Hyperplasia; Lipids; Materials Testing; Models, Animal; Platelet Aggregation Inhibitors; Prosthesis Design; Sirolimus; Stainless Steel; Surface Properties; Sus scrofa; Ticlopidine; Wound Healing

We sought to assess changes in antirestenotic efficacy of drug-eluting stents (DES) by restudying subjects at 2 time points after coronary stenting (6 to 8 months and 2 years) and to compare differences in time courses of late luminal loss (LLL) between 3 different DES platforms in use at our institution.. DES therapy is associated with low levels of LLL at 6 to 8 months. The temporal course of neointimal formation after this time point remains unclear.. This prospective, observational, systematic angiographic follow-up study was conducted at 2 centers in Munich, Germany. Patients underwent stenting with permanent-polymer rapamycin-eluting stents (RES), polymer-free RES, or permanent-polymer paclitaxel-eluting stents (PES). The primary end point was delayed LLL (the difference in in-stent LLL between 6 to 8 months and 2 years).. Of 2,588 patients undergoing stenting, 2,030 patients (78.4%) had 6- to 8-month angiographic follow-up and were enrolled in the study. Target lesion revascularization was performed in 259 patients; these patients were not considered for further angiographic analysis. Of 1,771 remaining patients, 1,331 had available 2-year reangiographic data (75.2%). Overall mean (SD) delayed LLL was 0.12 +/- 0.49 mm (0.17 +/- 0.50 mm, 0.01 +/- 0.42 mm, and 0.13 +/- 0.50 mm in permanent-polymer RES, polymer-free RES, and permanent-polymer PES groups, respectively [p < 0.001]). In multivariate analysis, only stent type (in favor of polymer-free RES) predicted delayed LLL.. Ongoing erosion of luminal caliber beyond 6 to 8 months after the index procedure is observed following DES implantation. Absence of permanent polymer from the DES platform seems to militate against this effect.

Topics: Aged; Angioplasty, Balloon, Coronary; Cardiovascular Agents; Coronary Angiography; Coronary Artery Disease; Coronary Restenosis; Drug-Eluting Stents; Female; Germany; Humans; Hyperplasia; Logistic Models; Male; Middle Aged; Paclitaxel; Polymers; Prospective Studies; Prosthesis Design; Risk Assessment; Sirolimus; Time Factors; Treatment Outcome

Topics: Angioplasty, Balloon, Coronary; Animals; Cardiovascular Agents; Coronary Artery Disease; Coronary Restenosis; Coronary Vessels; Drug-Eluting Stents; Humans; Hyperplasia; Paclitaxel; Polymers; Prosthesis Design; Risk Assessment; Sirolimus; Time Factors; Treatment Outcome; Tunica Intima

There is a hypothesis that advanced neointimal stent coverage may protect against stent thrombosis. In the present study, differences in neointimal growth and prevalence of in-stent thrombus between paclitaxel- and sirolimus-eluting stent (PES and SES) were evaluated by optical coherence tomography (OCT).. Follow-up angiographic and OCT examinations at approximately 6 months were performed for 40 patients (20 PES, 20 SES). Late loss was measured by quantitative coronary angiography. Neointimal hyperplasia (NIH) thickness on stent struts was measured by cross-sectional OCT images at 1 mm intervals. After measuring the NIH area in each cross-section, NIH volume was calculated as integral of NIH area within the stent. Late loss, NIH thickness, and NIH volume were greater for PES than for SES (0.42 +/-0.44 vs 0.13 +/-0.12 mm, 118 +/-141 vs 31 +/-39 mum, 53.2 +/-30.5 vs 24.3 +/-14.0 mm(3); P<0.05, respectively). In-stent thrombus was found more frequently in PES than in SES (50 vs 15%; P=0.02).. Although the degree of neointimal growth in PES was generally greater, in-stent thrombus was more common compared with SES. Presence of thrombus in first-generation drug-eluting stents was not related to advanced neointimal growth.

Topics: Adult; Aged; Aged, 80 and over; Angioplasty, Balloon, Coronary; Cardiovascular Agents; Cell Proliferation; Coronary Angiography; Coronary Stenosis; Coronary Thrombosis; Drug-Eluting Stents; Female; Humans; Hyperplasia; Male; Middle Aged; Paclitaxel; Platelet Aggregation Inhibitors; Risk Assessment; Risk Factors; Severity of Illness Index; Sirolimus; Time Factors; Tomography, Optical Coherence; Treatment Outcome; Tunica Intima

Topics: Angioplasty, Balloon, Coronary; Cardiovascular Agents; Coronary Restenosis; Coronary Stenosis; Drug-Eluting Stents; Humans; Hyperplasia; Myocardial Infarction; Prosthesis Design; Sirolimus; Thrombosis; Time Factors; Treatment Outcome

The aim of this study was to explore the determinants of neointimal coverage after sirolimus-eluting stent (SES).. Although SES has significantly reduced in-stent restenosis by inhibiting neointimal hyperplasia, insufficient neointimal coverage after stenting might result in adverse outcomes.. We evaluated 28 SES lesions with both angioscopy and intravascular ultrasound (IVUS). Quantitative assessments of the lesions and stent expansion were performed by IVUS at the time of stent implantation, and degree of neointimal coverage was judged by angioscopy at follow-up (11 +/- 6 months) whether the stent struts were embedded by the neointima ("complete/incomplete" neointimal coverage).. "Complete" coverage was identified in 10 (36%), and "incomplete" coverage was identified in 18 (64%). Time from the stenting to angioscopy as well as the lesion and procedural characteristics were similar between the complete and incomplete coverage groups. The IVUS parameters were also similar, except for the final minimum stent cross-sectional area (CSA) (7.0 +/- 1.8 mm(2) in complete vs. 5.3 +/- 1.9 mm(2) in incomplete, p = 0.02) and lumen CSA at the distal reference site (6.1 +/- 1.4 mm(2) in complete vs. 4.9 +/- 1.2 mm(2) in incomplete, p = 0.02). The ratio of the stent area to the vessel area was significantly larger in the complete coverage than in the incomplete coverage group (0.52 +/- 0.11 vs. 0.39 +/- 0.09, p = 0.002).. Adequate stent sizing relative to the vessel size might contribute to the angioscopically complete neointimal coverage after SES implantation.

Topics: Adult; Aged; Angioplasty, Balloon, Coronary; Angioscopy; Cardiovascular Agents; Cell Proliferation; Coronary Angiography; Coronary Stenosis; Coronary Vessels; Drug-Eluting Stents; Female; Humans; Hyperplasia; Male; Middle Aged; Prosthesis Design; Retrospective Studies; Sirolimus; Time Factors; Treatment Outcome; Tunica Intima; Ultrasonography, Interventional

Topics: Angioplasty, Balloon, Coronary; Angioscopy; Cardiovascular Agents; Cell Proliferation; Coronary Angiography; Coronary Stenosis; Coronary Vessels; Drug-Eluting Stents; Humans; Hyperplasia; Prosthesis Design; Sirolimus; Time Factors; Treatment Outcome; Tunica Intima; Ultrasonography, Interventional

Topics: Angioplasty, Balloon, Coronary; Animals; Cardiovascular Agents; Coated Materials, Biocompatible; Coronary Restenosis; Coronary Stenosis; Drug-Eluting Stents; Humans; Hyperplasia; Polymers; Prosthesis Design; Risk Assessment; Severity of Illness Index; Tacrolimus; Time Factors; Treatment Outcome; Xylenes

Intimal hyperplasia is a major cause of restenosis after the interventional or surgical treatment of occlusive arterial disease. We investigated the effects of clopidogrel, calcium dobesilate, nebivolol, and atorvastatin on the development of intimal hyperplasia in rabbits after carotid venous bypass surgery. We divided 40 male New Zealand rabbits into 4 study groups and 1 control group. After occluding the carotid arteries of the rabbits, we constructed jugular venous grafts between the proximal and the distal segments of the occluded artery. Thereafter, group 1 (control) received no medication. We administered daily oral doses of clopidogrel to group 2, calcium dobesilate to group 3, nebivolol to group 4, and atorvastatin to group 5. The rabbits were killed 28 days postoperatively. The arterialized jugular venous grafts were extracted for histopathologic examination. Intimal thicknesses were 42.87 +/- 6.95 microm (group 2), 46.5 +/- 9.02 microm (group 3), 34.12 +/- 5.64 microm (group 4), and 48.37 +/- 6.16 microm (group 5), all significantly less than the 95.12 +/- 9.93 microm in group 1 (all P < 0.001). Medial thicknesses were 94 +/- 6 microm (group 2), 101.5 +/- 13.52 microm (group 3), 90.5 +/- 9.69 microm (group 4), and 101.37 +/- 7.99 microm (group 5), all significantly thinner than the 126.62 +/- 13.53 microm in group 1 (all P < 0.001). In our experimental model of carotid venous bypass grafting in rabbits, clopidogrel, calcium dobesilate, nebivolol, and atorvastatin each effectively reduced the development of intimal hyperplasia. Herein, we discuss our findings and review the medical literature.

Topics: Administration, Oral; Animals; Atorvastatin; Benzopyrans; Calcium Dobesilate; Cardiovascular Agents; Carotid Stenosis; Clopidogrel; Disease Models, Animal; Ethanolamines; Graft Occlusion, Vascular; Heptanoic Acids; Hyperplasia; Jugular Veins; Male; Nebivolol; Pyrroles; Rabbits; Ticlopidine; Tunica Intima; Vascular Surgical Procedures

Baicalein (5,6,7-trioxyflavone-7-O-beta-D-glucuronide) derived from the Chinese herb Scutellaria baicalensis is well known as a lipoxygenase inhibitor. We investigated baicalein-mediated inhibitory effects on vascular smooth-muscle cell (VSMC) proliferation and intimal hyperplasia by balloon angioplasty in the rat. In vascular injury studies, baicalein significantly suppressed intimal hyperplasia by balloon angioplasty. Baicalein significantly inhibited cell proliferation via a lipoxygenase-independent pathway using [(3)H]thymidine incorporation, 3-(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide (MTT), and flow cytometry assays. At the concentrations used, no cytotoxic effect on cell culture was found. Baicalein blocks cell-cycle progression in S/G2/M phase, consistent with the cell-cycle effects, baicalein significant inhibited cyclin D1, p42/44 mitogen-activated protein kinase (MAPK), and Akt phosphorylation without change in the other cell-cycle regulatory proteins. Furthermore, baicalein attenuated serum-induced deoxyribonucleic acid (DNA) binding activity of nuclear factor kappa B (NF-kappaB). These results show that baicalein blocks cell proliferation via blocking cell-cycle progression and proliferating events, including p42/44 MAPK and Akt activations as well as NF-kappaB activation. It also inhibits intimal hyperplasia after balloon vascular injury in the rat, indicating the therapeutic potential for treating restenosis after arterial injury.

Topics: Animals; Apoptosis; Cardiovascular Agents; Carotid Stenosis; Catheterization; Cell Cycle; Cell Proliferation; Extracellular Signal-Regulated MAP Kinases; Flavanones; Hyperplasia; Muscle, Smooth, Vascular; NF-kappa B; Phosphorylation; Proto-Oncogene Proteins c-akt; Rats; Rats, Wistar; Signal Transduction; Tunica Intima

A significant fraction of vascular smooth muscle cells (VSMCs) undergo rapid apoptosis after balloon angioplasty. In this study, we tested the hypothesis that protecting VSMCs from undergoing apoptosis prevents the cascade of events that lead to intimal hyperplasia.. Rapamycin-loaded gel-like nanoparticles (mean diameter, 54+/-5 nm) were infused locally in a rat carotid artery model of vascular injury. The drug has both antiapoptotic and antiproliferative effects on VSMCs and hence was selected for the current study. Localized delivery of nanoparticles sustained the drug level in the target artery for >2 weeks; demonstrated significant inhibition of hyperplasia (intima/media ratio, 1.5+/-0.02 versus 2.7+/-0.6; P<0.01); and most importantly, re-endothelialized the injured artery (endothelium coverage: treated 82% versus control 28%). We also demonstrated inhibition of activation of caspase-3/7 enzymes in the treated artery, preventing VSMCs from undergoing apoptosis and subsequent infiltration of macrophages.. It may be postulated that the localized delivery of rapamycin inhibited apoptosis of VSMCs, minimizing the inflammatory response to the injury and, thus, creating conditions conducive to vascular repair (re-endothelialization). Unlike stenting, which can lead to thrombosis and increased risk for in-stent restenosis, our approach could eliminate or minimize long-term complications because the injured artery undergoes a natural process of re-endothelialization.

Topics: Animals; Apoptosis; Cardiovascular Agents; Carotid Arteries; Caspase Inhibitors; Cells, Cultured; Endothelium, Vascular; Hyperplasia; Immunohistochemistry; In Situ Nick-End Labeling; Macrophages; Male; Muscle, Smooth, Vascular; Nanoparticles; Rats; Rats, Sprague-Dawley; Sirolimus; Tunica Intima

Restenosis due to intimal hyperplasia following percutaneous transluminal angioplasty limits its long-term efficacy. We evaluated the effect of colchicine on the development of intimal hyperplasia following balloon angioplasty and on the vascular endothelial growth factor (VEGF) expression in leukocytes.. Adult dogs underwent balloon angioplasty of the right iliofemoral artery. Group 1 served as control, while groups 2 and 3 (six animals per group) received 0.1 and 0.5 mg/kg/d of colchicine p.o., respectively, starting 2 d before angioplasty and continued for 14 d. Before angioplasty and at day 14, blood samples were collected for drug toxicity analysis and the determination of leukocyte expression of VEGF. Animals were euthanized and iliofemoral arteries were perfusion fixed in situ and processed for histological and morphometric analysis.. Balloon angioplasty without colchicine resulted in 446% (P < 0.001), 111% (P = 0.7), and 267% (P < 0.001) increase in intimal and medial thickness and intima/media ratio compared with contralateral uninjured iliofemoral arteries. Low-dose and high-dose colchicine resulted in 32% and 58% reduction in intima/media ratio, respectively (both P < 0.001). VEGF expression in leukocytes of control group was up-regulated (40%), but was down-regulated by 12% and 55%, respectively, in low-dose and high-dose colchicine groups at 2 wk after angioplasty compared with preangioplasty expression. The results of complete blood count and serum transaminases and creatinine were within normal range.. This study demonstrates that oral colchicine for 2 wk significantly reduces intimal hyperplasia following balloon angioplasty in dogs through down-regulation of leukocyte VEGF expression and without apparent toxicity.

Topics: Angioplasty, Balloon; Animals; Cardiovascular Agents; Colchicine; Disease Models, Animal; Dogs; Down-Regulation; Femoral Artery; Gene Expression; Hyperplasia; Leukocytes; Reverse Transcriptase Polymerase Chain Reaction; Tunica Intima; Vascular Endothelial Growth Factor A

The goal of this study was to evaluate the ability of recombinant human thrombomodulin (rTM) to inhibit neointimal hyperplasia when bound to expanded polytetrafluoroethylene (ePTFE) stent grafts placed in a porcine balloon injured carotid artery model.. The left carotid artery of male pigs, weighing 25 to 30 Kg, was injured with an angioplasty balloon. Two weeks later either a non-coated standard ePTFE stent graft (Viabahn, 6 x 25 mm, W. L. Gore & Associates) or a rTM coated stent graft was implanted into the balloon-injured segment using an endovascular technique. Carotid angiography was performed at the time of the balloon injury, two weeks later and then at 4 weeks to assess the degree of luminal stenosis. One month after stent graft deployment, the grafts were explanted following in situ perfusion fixation for histological analysis. The specimens were then cross-sectioned into proximal, middle and distal segments, and the residual arterial lumen and intimal to media (I/M) ratios were calculated with computerized planimetry.. rTM binding onto ePTFE-grafts was confirmed by functional activation of protein C and histopathology with immuno-scanning electron microscopy, backscatter electron emission imaging and x-ray microanalysis. All seven of the rTM coated stent grafts and six of the seven uncoated stent grafts were patent at the time of explantation. The mean luminal diameter of the rTM coated stents was 93% +/- 2.0% of the original diameter, compared with 67% +/- 23% (P = .006) in the control group. Histological analysis demonstrated that the area obliterated by intimal hyperplasia at the proximal portion of the rTM stent was -27% compared with the control group: (2.73 +/- 0.69 mm(2), vs 3.47 +/- 0.67 mm(2), P <.05).. Neointimal hyperplasia is significantly inhibited in ePTFE stent grafts coated with rTM compared with uncoated grafts, as documented by improved luminal diameter by angiography and by computerized planimetry measurements of residual lumen area. These findings suggest that binding of recombinant human thrombomodulin onto ePTFE grafts may improve the long-term patency of covered stents grafts.. Decrease of neointimal hyperplasia of the magnitude observed in this study could significantly improve blood flow and patency of small caliber prosthetic grafts. If the durability of these results can be confirmed by long-term studies, this technique may prove useful in preventing graft stenosis and arterial thrombosis following angioplasty or vascular bypass procedures.

Topics: Angioplasty, Balloon; Animals; Cardiovascular Agents; Carotid Artery Injuries; Carotid Stenosis; Coated Materials, Biocompatible; Disease Models, Animal; Drug-Eluting Stents; Feasibility Studies; Humans; Hyperplasia; Male; Polytetrafluoroethylene; Prosthesis Design; Radiography; Recombinant Proteins; Swine; Thrombomodulin; Time Factors

Drug-eluting stents are increasingly used to reduce in-stent restenosis and adverse cardiac events after percutaneous coronary interventions. However, the race for the ideal drug-eluting stent is still on, with special regard to the best stent-coating system and the most effective and less toxic drug. Fludarabine, a nucleoside analog, has both anti-inflammatory and antiproliferative cellular effects. The aim of the present study was to assess the cellular and molecular effects of fludarabine on vascular smooth muscle cell (VSMC) growth in vitro and in vivo and the feasibility and efficacy of a fludarabine-eluting stent. To study the biomolecular effects of fludarabine on VSMC proliferation in vitro, rat VSMCs were grown in the presence of 50 microM fludarabine or in the absence of the same. To evaluate the in vivo effect of this drug, male Wistar rats underwent balloon injury of the carotid artery, and fludarabine was locally delivered at the time of injury. Finally, fludarabine-eluting stents were in-laboratory manufactured and tested in a rabbit model of in-stent restenosis. Fludarabine markedly inhibited VSMC proliferation in cell culture. Furthermore, fludarabine reduced neointimal formation after balloon angioplasty in a dose-dependent manner, and fludarabine-eluting stents reduced neointimal hyperplasia by approximately 50%. These in vitro and in vivo cellular effects were specifically associated with the molecular switch-off of signal transducer and activator of transcription (STAT)-1 activation, without affecting other STAT proteins. Fludarabine abolishes VSMC proliferation in vitro and reduces neointimal formation after balloon injury in vivo through specific inhibition of STAT-1 activation. Fludarabine-eluting stents are feasible and effective in reducing in-stent restenosis in rabbits.

Topics: Angioplasty, Balloon; Animals; Aorta; Cardiovascular Agents; Carotid Artery Injuries; Carotid Stenosis; Cell Proliferation; Cells, Cultured; Disease Models, Animal; Dose-Response Relationship, Drug; Feasibility Studies; Hyperplasia; Janus Kinase 2; Male; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Phosphorylation; Prosthesis Design; Rabbits; Rats; Rats, Wistar; RNA, Antisense; STAT1 Transcription Factor; Stents; Time Factors; Transfection; Tunica Intima; Vidarabine

This study evaluated the effect of a bioabsorbable mesh containing paclitaxel on neointimal hyperplasia in a sheep model of dialysis access failure.. Forty neutered male sheep were randomized to one of five parallel groups: no mesh; or a 3-cm x 6-cm mesh with 0.0, 0.3, 0.7, or 1.2 microg/mm(2) of paclitaxel for a total dose of 0.0, 0.6, 1.3, or 2.2 mg, respectively. Commercially available 6-mm internal diameter expanded polytetrafluoroethylene grafts were surgically placed between the left common carotid artery and the right external jugular vein. For those animals randomized to one of the mesh groups, the mesh was placed around the distal end of the graft and venous anastomosis. Patency was assessed at weekly intervals throughout the study. Animals were euthanized 8 weeks after implantation, and grafts and veins were harvested. After histologic processing, six cross sections were cut at the venous end of the graft and vessel. The primary and secondary efficacy outcome measures, respectively, were the area and capillary density of the neointima at the graft-vein anastomosis. Histologic analyses were also performed to investigate the effects of the paclitaxel-eluting mesh on the anastomotic site.. Grafts occluded before the scheduled sacrifice in five animals, and they were excluded from the study and not replaced. Control animals developed significant neointimal hyperplasia at the cross section taken perpendicular to the graft at its most distal end: the neointimal area measured 10.5 +/- 6.8 mm(2) in the no mesh group and 6.4 +/- 3.2 mm(2) in the zero-dose mesh group (P = .28). In contrast, neointimal area was significantly reduced in the paclitaxel mesh groups: 0.9 +/- 1.4 mm(2) in the 0.3 microg/mm(2) group (P = .008 vs zero-dose mesh), 1.3 +/- 1.5 mm(2) in the 0.7 microg/mm(2) group (P = .004 vs zero-dose mesh), and 1.2 +/- 1.4 mm(2) in the 1.2 microg/mm(2) group (P = .008 vs zero-dose mesh). Capillary density in the neointima at the graft-vein anastomosis decreased with paclitaxel and was significantly reduced in the paclitaxel mesh groups with 0.3 and 1.2 mug/mm(2) compared with the zero-dose mesh control (3.6 +/- 2.9 vs 8.9 +/- 5.6 per mm(2) [P = .022] and 1.1 +/- 1.7 vs 8.9 +/- 5.6 per mm(2) [P = .001] respectively). The paclitaxel mesh had no significant effect on healing of the anastomosis or on the thickness of the adjacent vein.. In this model, the paclitaxel-eluting mesh significantly reduced neointimal hyperplasia and neointimal capillary density without apparent toxicity to the adjacent vein.

Topics: Anastomosis, Surgical; Animals; Arteriovenous Shunt, Surgical; Cardiovascular Agents; Drug Delivery Systems; Graft Occlusion, Vascular; Hyperplasia; Male; Models, Animal; Paclitaxel; Prostheses and Implants; Random Allocation; Surgical Mesh; Treatment Failure; Tunica Intima; Vascular Patency

Smooth muscle cell proliferation (SMC) is a pivotal factor in the development of intimal hyperplasia after vascular injury. A number of growth factors, including insulin-like growth factor-1 (IGF-1), have been shown to be involved in SMC proliferation. We evaluated the effect of picropodophyllin (PPP), a new IGF-1 receptor inhibitor, in the prevention of SMC proliferation and development of intimal hyperplasia after vascular injury.. The effects of systemic administration of PPP on intimal hyperplasia were studied in a balloon rat carotid injury model. Lesions were quantified by morphometry and SMC proliferation and apoptosis was studied by immunohistochemical staining for proliferating cell nuclear antigen (PCNA) and activated caspase 3, respectively. The effect of PPP on rat aortic SMC proliferation and apoptosis was studied in vitro by using cell counting, 3[H]-thymidine incorporation, and a flow cytometry assay for annexin V. Phosphorylation of the IGF-1 receptor, protein kinase B (Akt), and extracellular signal-regulated kinase 1/2 (ERK1/2) in vitro and in vivo were analyzed by using Western blotting.. PPP inhibited IGF-1-mediated SMC proliferation in vitro but no significant increase in apoptosis was detected. In rats treated with PPP, a more than a twofold reduction in carotid intima area was observed 2 weeks after balloon injury, a significant decrease in PCNA staining was demonstrated in early lesions, but activated caspase 3 was not detected. In addition, PPP attenuated phosphorylation of the IGF-1 receptor, Akt, and ERK1/2 in IGF-1-stimulated SMCs in vitro, and a reduced phosphorylation of the IGF-1 receptor and Akt was found in balloon-injured carotid arteries in rats treated with PPP.. These results show that PPP potently blocks IGF-1-mediated phosphorylation of the IGF-1 receptor in SMCs, decreases downstream Akt and ERK1/2 activation, inhibits SMC replication, and subsequently attenuates intimal hyperplasia after balloon injury of rat carotid arteries.

Topics: Animals; Apoptosis; Cardiovascular Agents; Carotid Artery Injuries; Catheterization; Cell Proliferation; Disease Models, Animal; Dose-Response Relationship, Drug; Hyperplasia; Insulin-Like Growth Factor I; Male; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Muscle, Smooth, Vascular; Phosphorylation; Podophyllotoxin; Proto-Oncogene Proteins c-akt; Rats; Rats, Sprague-Dawley; Receptor, IGF Type 1; Signal Transduction; Time Factors; Tunica Intima

Strictly intravascular approaches for the treatment of postangioplasty restenosis are effective in the intima and the inner parts of the media but may be insufficient to control redundant pathways in the more outer parts of the media and the adventitia. An inverse situation may occur subsequently to a strictly extravascular approach, like the recently suggested pericardial approach in pigs. We hypothesized that simultaneous intra/extravascular administration of anti-restenotic agents inhibits restenosis by blocking all stimulatory pathways in the entire arterial wall.. Fresh hearts of 25 domestic pigs were obtained from a local slaughterhouse. Left anterior descending coronary arteries (LAD) were harvested, cut into cylindric 5 mm segments, and cultured as ex vivo porcine organ cultures (POCs). After 9 bar ballooning simultaneous intra/extravascular administration of high dose diltiazem (50 microg/mL) was carried out for a period of 1, 2, 3, 4, 5, 6, and 7 days. At day 7 and 28 proliferative activity (BrdU), neointimal thickening, and staining against smooth muscle alpha-actin and vWF was analysed.. 7 days after ballooning administration of diltiazem for 4, 5, 6, and 7 days inhibited reactive cell proliferation by more than 50% (n.s.) as compared to control, 28 days after ballooning administration for 6 and 7 days inhibited neointimal thickening by more than 75% (p < 0.05). Simultaneous intra/extravascular administration of high dose diltiazem did not affect the expression of vWF in endothelial cells or smooth muscle alpha-actin in smooth muscle cells.. Simultaneous intra/extravascular administration of high dose diltiazem (50 microg/mL) has to be maintained for at least 6 days to achieve a significant inhibition of neointimal thickening. The data demonstrate the importance of the maximal reactive cell proliferation (= day 7 in the POC-model) for the calculation of the duration of the treatment period.

Topics: Angioplasty, Balloon; Animals; Cardiovascular Agents; Cell Division; Coronary Restenosis; Coronary Vessels; Diltiazem; Endothelium, Vascular; Hyperplasia; Muscle, Smooth, Vascular; Organ Culture Techniques; Swine; Tunica Intima

Dopamine is an endogenous inotropic agent commonly used during coronary artery surgery and in the medical therapy of a revascularized patient. In this study the responses of intimal hyperplastic vein grafts to dopamine are examined.. The in vitro isometric tension responses to dopamine of common carotid jugular vein bypass grafts in New Zealand White rabbits were determined. The responses were compared to those obtained in the jugular vein and in the common carotid artery. Both endothelialized and denuded vessels were precontracted with prostaglandin F(2alpha) and the responses to dopamine were assessed. The contributions of nitric oxide and prostanoids to the response were also determined.. Each vessel showed a biphasic dose response to dopamine with relaxation at low concentrations followed by contraction at high concentrations. Dopamine relaxation in the jugular vein was endothelial independent while in the carotid artery it was endothelial dependent and decreased. The sensitivity of both vessels was significantly greater than the vein graft (6.62 +/- 0.12; P < 0. 05); however, after endothelial denudation, the sensitivity of dopamine-mediated relaxation of the vein graft (8.91 +/- 0.09) was significantly enhanced. Preincubation with L-NMMA (to block NO synthesis) inhibited vein graft relaxation to dopamine and preincubation with indomethacin (to block cyclooxygenase activity) inhibited carotid artery relaxation to dopamine. Addition of phenoxybenzamine, a broad alpha-adrenergic antagonist, enhanced dopamine relaxation in the jugular vein and depressed the relaxation in the carotid artery. There was no effect on the dopamine response in the vein graft. Jugular vein and carotid artery responded to dopamine with cholera toxin-sensitive (Galpha(s)) responses. In contrast, dopamine relaxation in the vein graft was enhanced by inhibition of Galpha(s).. Dopamine relaxation in vein grafts is mediated in part by NO but not by either prostanoids or alpha-adrenergic receptor activation. It is diminished compared to native vessels due to an endothelium-dependent, Galpha(s)-mediated pathway.

Topics: Adjuvants, Immunologic; Adrenergic alpha-Antagonists; Animals; Cardiotonic Agents; Cardiovascular Agents; Carotid Artery, Common; Cholera Toxin; Dopamine; Dose-Response Relationship, Drug; Endothelium, Vascular; Enzyme Inhibitors; Graft Occlusion, Vascular; GTP-Binding Proteins; Hyperplasia; Indomethacin; Jugular Veins; Male; Nitric Oxide; omega-N-Methylarginine; Phenoxybenzamine; Prostaglandins; Rabbits; Receptors, Adrenergic, alpha; Receptors, Dopamine; Tunica Intima; Vasodilation

In-stent restenosis results primarily from neointimal hyperplasia. This study evaluated the efficacy and the optimal mode of administration of angiopeptin, a somatostatin analogue with antiproliferative activity, in a porcine coronary in-stent restenosis model.. Forty pigs were randomly assigned to one of four groups (n = 10 per group): (1) controls receiving saline infusion at the site of stent implantation via a local delivery catheter, (2) local treatment group receiving one-time treatment (200 (micrograms angiopeptin) at the site of stent placement, (3) systemic treatment group receiving continuous angiopeptin over a 1-week period via a subcutaneous osmotic pump (200 micrograms/kg total dose) and (4) combined local and systemic treatment group. Then, one oversized Palmaz-Schatz stent (mean ratio of stent to artery diameters, 1.3:1) was implanted in the left anterior descending coronary artery. The degree of neointimal reaction was evaluated 4 weeks later by angiography (maximal percent diameter stenosis), intravascular ultrasound (total in-stent neointimal volume), and histology (maximal area stenosis). Systemic treatment produced the least neointimal hyperplasia and significantly reduced in-stent restenosis compared with the control group by all end points, despite similar degrees of injury. Angiography showed 25 +/- 17% versus 50 +/- 17% diameter stenosis in the systemic angiopeptin group versus the control group (P < .0001), intravascular ultrasound revealed 23 +/- 10 versus 58 +/- 27 mm3 neointimal volume in the systemic angiopeptin versus control group (P = .0002), and histology showed 41 +/- 16% versus 69 +/- 18% area stenosis (P = .0016) in the systemic angiopeptin versus control group. Plasma angiopeptin levels revealed rapid clearance (within 6 hours) after local therapy, whereas the levels persisted for up to 2 weeks in the systemic group.. This study shows that continuous subcutaneous treatment with angiopeptin after stent implantation significantly reduces in-stent restenosis by inhibiting neointimal hyperplasia.

Topics: Animals; Cardiovascular Agents; Coronary Angiography; Coronary Disease; Hyperplasia; Injections, Subcutaneous; Oligopeptides; Peptides, Cyclic; Recurrence; Somatostatin; Stents; Swine; Tunica Intima; Ultrasonography, Interventional

In-stent restenosis results primarily from neointimal hyperplasia. In a previous study we showed that continuous subcutaneous Angiopeptin infusion for 1 week significantly reduces neointimal hyperplasia in a porcine coronary overstretch in-stent restenosis model. The present study evaluated the relative efficacy of immediate-release and sustained-release Angiopeptin in the same model.. Thirty pigs (n = 10 in each group) were randomly assigned to three groups: controls receiving no Angiopeptin (Group 1); a sustained-release treatment group receiving one time intramuscular administration of 20 mg of Angiopeptin (Group 2); and a systemic treatment group receiving continuous Angiopeptin over a 1-week period via a subcutaneous osmotic pump (200 micrograms/kg total dose) (Group 3). One oversized Palmaz-Schatz stent (mean stent/artery = 1.25) was subsequently implanted in the left anterior descending coronary artery. The degree of neointimal reaction was evaluated 4 weeks later by angiography (maximal per cent diameter stenosis) and histology (maximal neointimal area corrected for injury score).. A trend towards a reduction in diameter stenosis was observed by angiography, despite a similar degree of injury (25 +/- 17% in Group 1, 13 +/- 8% in Group 2, and 14 +/- 9% in Group 3; P = 0.072 by ANOVA). Histology demonstrated that both Angiopeptin treatment strategies significantly reduced in-stent neointimal area compared with the control group (1.65 +/- 0.97 mm2 in Group 1 versus 0.93 +/- 0.41 mm2 in Group 2 versus 0.85 +/- 0.28 mm2 in Group 3; P = 0.016 by ANOVA). Measurement of plasma Angiopeptin levels revealed comparable levels in both treatment groups, which persisted for up to 2 weeks.. This study shows that single-dose intramuscular administration of sustained-release Angiopeptin reduces in-stent restenosis as effectively as the prolonged systemic treatment requiring a subcutaneous pump. Thus, a practical, effective, pharmacologic therapy for preventing in-stent restenosis may be available and should be evaluated in patients.

Topics: Animals; Cardiovascular Agents; Coronary Angiography; Coronary Disease; Coronary Vessels; Hyperplasia; Injections, Intramuscular; Oligopeptides; Peptides, Cyclic; Radioimmunoassay; Random Allocation; Somatostatin; Stents; Swine; Tunica Intima