Computational Analysis of Mechanical Performance for Composite Polymer Biodegradable Stents

Bioresorbable stents (BRS) represent the latest generation of vascular scaffolds used for minimally invasive interventions. They aim to overcome the shortcomings of established bare-metal stents (BMS) and drug-eluting stents (DES). Recent advances in the field of bioprinting offer the possibility of combining biodegradable polymers to produce a composite BRS. Evaluation of the mechanical performance of the novel composite BRS is the focus of this study, based on the idea that they are a promising solution to improve the strength and flexibility performance of single material BRS. Finite element analysis of stent crimping and expansion was performed. Polylactic acid (PLA) and polycaprolactone (PCL) formed a composite stent divided into four layers, resulting in sixteen unique combinations. A comparison of the mechanical performance of the different composite configurations was performed. The resulting stresses, strains, elastic recoil, and foreshortening were evaluated and compared to existing experimental results. Similar behaviour was observed for material configurations that included at least one PLA layer. A pure PCL stent showed significant elastic recoil and less shortening compared to PLA and composite structures. The volumetric ratio of the materials was found to have a more significant effect on recoil and foreshortening than the arrangement of the material layers. Composite BRS offer the possibility of customising the mechanical behaviour of scaffolds. They also have the potential to support the fabrication of personalised or plaque-specific stents.

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Vollständig resorbierbare Stents – eine neue Ära in der Behandlung der koronaren Herzkrankheit?

Praxis ◽

10.1024/1661-8157/a002584 ◽

2017 ◽

Vol 106 (2) ◽

pp. 85-89

Author(s):

Zaid Sabti ◽

Raban Jeger

Keyword(s):

Bare Metal Stents ◽

Drug Eluting Stents ◽

Metal Stents ◽

Bare Metal ◽

Vascular Scaffolds ◽

Drug Eluting ◽

Bioresorbable Vascular Scaffolds

Zusammenfassung. Die perkutane Ballonangioplastie revolutionierte die Behandlung der koronaren Herzkrankheit. Der Einsatz von Gefässstützen (Stents) setzte diese Revolution fort. Nach den reinen Metallstents (Bare metal stents, BMS) und den Medikamenten-beschichteten Stents (drug-eluting stents, DES) folgen nun bioresorbierbare Stents (bioresorbable vascular scaffolds, BVS). Im Gegensatz zu den ersten zwei Stent-Generationen werden die BVS nach einer bestimmten Zeit vollständig abgebaut und versprechen eine Antwort für bisher ungelöste Probleme von BMS und DES.

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Everolimus-eluting bioresorbablecoronary scaffold in Asian patients; a 2-yearfollow-up

Journal of the Pakistan Medical Association ◽

10.47391/jpma.1149 ◽

2020 ◽

pp. 1-11

Author(s):

Muhammad Abdul Salam Azad ◽

Uzma Gul ◽

Asim Javed

Keyword(s):

Case Series ◽

Bare Metal Stents ◽

Metal Stents ◽

Asian Patients ◽

Implantation Techniques ◽

Bioresorbable Stent ◽

Vascular Scaffolds ◽

Drug Eluting ◽

Artery Disease ◽

Absorb Bvs

Abstract Indo-Pakistan population has one of the highest risk of coronary artery disease(CAD) in the world.1Percutaneous interventions with the use of stents has been the mainstay of treatment for CAD, evolving from balloon angioplasty to bare metal stents and then to drug eluting stents. However, there are a few drawbacks related to the metal implant in the coronary, leading to the development of bio-resorbable vascular scaffolds(BVS). This case series studies the implantation techniques and 24 month clinical outcome of bioresorbable stent Absorb at Rawalpindi Institute of Cardiology. From November 1, 2013 till June 30, 2018. Fifty patients undergoing angioplasty with Absorb BVS as elective or primary PCI were enrolled. Case selection was at the discretion of the operator. Patients were followed up clinically. Repeat angiogram was conducted if clinically indicated. Continuous...

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Flow Through Coated Coronary Stented Arteries: A Review

Volume 2: Biomedical and Biotechnology Engineering; Nanoengineering for Medicine and Biology ◽

10.1115/imece2011-64621 ◽

2011 ◽

Author(s):

Aneesha Gogineni ◽

T. S. Ravigururajan

Keyword(s):

Bare Metal Stents ◽

Drug Eluting Stents ◽

Metal Stents ◽

Bare Metal ◽

Carbon Coatings ◽

Neointimal Proliferation ◽

Biodegradable Stents ◽

Stenosed Artery ◽

Drug Eluting ◽

Flow Through

This paper reviews the recent literature on the stent applications and their recent advancements due to some controversies. The paper consists of two parts flow modeling of stents and a comparison between normal and stenosed artery. It also includes a comparison of stent geometries to determine hemodynamically favorable stents. In spite of many advantages bare metal stents are found to be unfavorable. However the study of stents based on flow and design recommend stent coatings. In comparison with bare metal stents, metal coated stents proved to be more efficient in terms of restenosis. Most of the metal coatings have less fluoroscopic visibility and low tensile strengths and hence drug eluting stents were studied. Although drug eluting stents were proved to be efficient in controlling restenosis, they have issues in patients with co-morbidities. For this reason, polymer and carbon coatings were studied in detail which showed better results than drug eluting stents. Biodegradable stents on the other hand inhibit smooth muscle cell proliferation and a decrease in neointimal proliferation. At present research on polymer, carbon and biodegradable stents are actively pursued for stent therapy applications.

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Drug-eluting stents for treatment of focal infrapopliteal lesions

VASA ◽

10.1024/0301-1526/a000170 ◽

2012 ◽

Vol 41 (2) ◽

pp. 90-95 ◽

Cited By ~ 10

Author(s):

Rastan ◽

Noory ◽

Zeller

Keyword(s):

Limb Salvage ◽

Bare Metal Stents ◽

Target Lesion ◽

Drug Eluting Stents ◽

Metal Stents ◽

Target Lesion Revascularisation ◽

Randomized Studies ◽

Drug Eluting ◽

The Mean

We have investigated the role of drug-eluting stents on patency rates after treatment of focal infrapopliteal lesions in patients with intermittent claudication and critical limb ischemia. Reports indicate that drug-eluting stents reduce the risk of restenosis after percutaneous infrapopliteal artery revascularization. A Pub Med, EMBASE, Cochrane database review search of non-randomized studies investigating patency rates, target lesion revascularisation rates, limb salvage rates and mortality rates in an up to 3-year follow-up period after drug-eluting stent placement was conducted. In addition, preliminary results of randomized studies comparing drug-eluting stents with bare-metal stents and plain balloon angioplasty in treatment of focal infrapopliteal lesions were included in this review. A total of 1039 patients from 10 non-randomized and randomized studies were included. Most commonly used drug-eluting stents were sirolimus-eluting. The mean follow-up period was 12.6 (range 8 - 24). The mean 1-year primary patency rate was 86 ± 5 %. The mean target lesion revascularization rate and limb salvage rate was 9.9 ± 5 % and 96.6 %±4 %, respectively. Results from non-randomized and preliminary results from prospective, randomized trials show a significant advantage for drug-eluting stents in comparison to plain balloon angioplasty and bare-metal stents concerning target lesion patency and in parts target lesion revascularisation. No trial reveals an advantage for drug-eluting stents with regard to limb salvage and mortality.

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Faculty Opinions recommendation of Outcomes with various drug eluting or bare metal stents in patients with diabetes mellitus: mixed treatment comparison analysis of 22,844 patient years of follow-up from randomised trials.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.718173042.793487672 ◽

2013 ◽

Author(s):

Claudia Martinez

Keyword(s):

Bare Metal Stents ◽

Metal Stents ◽

Mixed Treatment Comparison ◽

Randomised Trials ◽

Comparison Analysis ◽

Treatment Comparison ◽

Mixed Treatment ◽

Patients With Diabetes ◽

Drug Eluting

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Faculty Opinions recommendation of Drug-Eluting or Bare-Metal Stents for Coronary Artery Disease.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.726696134.793524354 ◽

2016 ◽

Author(s):

Wilbert Aronow

Keyword(s):

Coronary Artery Disease ◽

Coronary Artery ◽

Bare Metal Stents ◽

Metal Stents ◽

Bare Metal ◽

Drug Eluting ◽

Artery Disease

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The Use of Bioactive Polymers for Intervention and Tissue Engineering: The New Frontier for Cardiovascular Therapy

Polymers ◽

10.3390/polym13030446 ◽

2021 ◽

Vol 13 (3) ◽

pp. 446 ◽

Cited By ~ 1

Author(s):

Francesco Nappi ◽

Antonio Nenna ◽

Domenico Larobina ◽

Giorgia Martuscelli ◽

Sanjeet Singh Avtaar Singh ◽

...

Keyword(s):

Bare Metal Stents ◽

Coronary Intervention ◽

Myocardial Infarctions ◽

Metal Stents ◽

Long Term Effects ◽

St Segment Elevation ◽

Advantages And Disadvantages ◽

Cardiovascular Therapy ◽

St Segment ◽

Drug Eluting

Coronary heart disease remains one of the leading causes of death in most countries. Healthcare improvements have seen a shift in the presentation of disease with a reducing number of ST-segment elevation myocardial infarctions (STEMIs), largely due to earlier reperfusion strategies such as percutaneous coronary intervention (PCI). Stents have revolutionized the care of these patients, but the long-term effects of these devices have been brought to the fore. The conceptual and technologic evolution of these devices from bare-metal stents led to the creation and wide application of drug-eluting stents; further research introduced the idea of polymer-based resorbable stents. We look at the evolution of stents and the multiple advantages and disadvantages offered by each of the different polymers used to make stents in order to identify what the stent of the future may consist of whilst highlighting properties that are beneficial to the patient alongside the role of the surgeon, the cardiologist, engineers, chemists, and biophysicists in creating the ideal stent.

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