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Islam P, Schaly S, Abosalha AK, Boyajian J, Thareja R, Ahmad W, Shum-Tim D, Prakash S. Nanotechnology in development of next generation of stent and related medical devices: Current and future aspects. WILEY INTERDISCIPLINARY REVIEWS. NANOMEDICINE AND NANOBIOTECHNOLOGY 2024; 16:e1941. [PMID: 38528392 DOI: 10.1002/wnan.1941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 12/08/2023] [Accepted: 01/03/2024] [Indexed: 03/27/2024]
Abstract
Coronary stents have saved millions of lives in the last three decades by treating atherosclerosis especially, by preventing plaque protrusion and subsequent aneurysms. They attenuate the vascular SMC proliferation and promote reconstruction of the endothelial bed to ensure superior revascularization. With the evolution of modern stent types, nanotechnology has become an integral part of stent technology. Nanocoating and nanosurface fabrication on metallic and polymeric stents have improved their drug loading capacity as well as other mechanical, physico-chemical, and biological properties. Nanofeatures can mimic the natural nanofeatures of vascular tissue and control drug-delivery. This review will highlight the role of nanotechnology in addressing the challenges of coronary stents and the recent advancements in the field of related medical devices. Different generations of stents carrying nanoparticle-based formulations like liposomes, lipid-polymer hybrid NPs, polymeric micelles, and dendrimers are discussed highlighting their roles in local drug delivery and anti-restenotic properties. Drug nanoparticles like Paclitaxel embedded in metal stents are discussed as a feature of first-generation drug-eluting stents. Customized precision stents ensure safe delivery of nanoparticle-mediated genes or concerted transfer of gene, drug, and/or bioactive molecules like antibodies, gene mimics via nanofabricated stents. Nanotechnology can aid such therapies for drug delivery successfully due to its easy scale-up possibilities. However, limitations of this technology such as their potential cytotoxic effects associated with nanoparticle delivery that can trigger hypersensitivity reactions have also been discussed in this review. This article is categorized under: Implantable Materials and Surgical Technologies > Nanotechnology in Tissue Repair and Replacement Therapeutic Approaches and Drug Discovery > Nanomedicine for Cardiovascular Disease Therapeutic Approaches and Drug Discovery > Emerging Technologies.
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Affiliation(s)
- Paromita Islam
- Biomedical Technology and Cell Therapy Research Laboratory, Department of Biomedical Engineering, Faculty of Medicine and Health Sciences, McGill University, Montreal, Quebec, Canada
| | - Sabrina Schaly
- Biomedical Technology and Cell Therapy Research Laboratory, Department of Biomedical Engineering, Faculty of Medicine and Health Sciences, McGill University, Montreal, Quebec, Canada
| | - Ahmed Kh Abosalha
- Biomedical Technology and Cell Therapy Research Laboratory, Department of Biomedical Engineering, Faculty of Medicine and Health Sciences, McGill University, Montreal, Quebec, Canada
- Pharmaceutical Technology Department, Faculty of Pharmacy, Tanta University, Tanta, Egypt
| | - Jacqueline Boyajian
- Biomedical Technology and Cell Therapy Research Laboratory, Department of Biomedical Engineering, Faculty of Medicine and Health Sciences, McGill University, Montreal, Quebec, Canada
| | - Rahul Thareja
- Biomedical Technology and Cell Therapy Research Laboratory, Department of Biomedical Engineering, Faculty of Medicine and Health Sciences, McGill University, Montreal, Quebec, Canada
| | - Waqar Ahmad
- Biomedical Technology and Cell Therapy Research Laboratory, Department of Biomedical Engineering, Faculty of Medicine and Health Sciences, McGill University, Montreal, Quebec, Canada
| | - Dominique Shum-Tim
- Division of Cardiac Surgery, Royal Victoria Hospital, McGill University Health Centre, McGill University, Faculty of Medicine and Health Sciences, Montreal, Quebec, Canada
| | - Satya Prakash
- Biomedical Technology and Cell Therapy Research Laboratory, Department of Biomedical Engineering, Faculty of Medicine and Health Sciences, McGill University, Montreal, Quebec, Canada
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Forkmann C, Pritsch M, Baumann-Zumstein P, Lootz D, Joner M. In vivo chronic scaffolding force of a resorbable magnesium scaffold. J Biomech 2024; 164:111988. [PMID: 38364489 DOI: 10.1016/j.jbiomech.2024.111988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 01/31/2024] [Accepted: 02/05/2024] [Indexed: 02/18/2024]
Abstract
The aim of this study is to qualitatively characterize the in vivo chronic scaffolding force of the Magmaris® Resorbable Magnesium Scaffold (RMS). This important parameter of scaffolds must be balanced between sufficient radial support during the healing period of the vessel and avoidance of long-term vessel caging. A finite element model was established using preclinical animal data and used to predict the device diameter and scaffolding force up to 90 days after implantation. To account for scaffold resorption, it included backbone degradation as well as formation of discontinuities as observed in vivo. The predictions of the model regarding acute recoil and chronic development of the device diameter were in good agreement with the preclinical data, supporting the validity of the model. It was found that after 28 and 90 days, the Magmaris® RMS retained 90 % and 47 % of its initial scaffolding force, respectively. The reduction in scaffolding force was mainly driven by discontinuities in the meandering segments. Finite element analysis combined with preclinical data is a reliable method to characterize the chronic scaffolding force.
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Affiliation(s)
| | | | | | - Daniel Lootz
- Biotronik AG, Ackerstraße 6, 8180 Bülach, Switzerland.
| | - Michael Joner
- German Heart Center Munich, Lazarettstraße 36, 80636 München, Germany.
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Cortese B, Kalkat H, Bathia G, Basavarajaiah S. The evolution and revolution of drug coated balloons in coronary angioplasty: An up-to-date review of literature data. Catheter Cardiovasc Interv 2023; 102:1069-1077. [PMID: 37870079 DOI: 10.1002/ccd.30891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 09/30/2023] [Indexed: 10/24/2023]
Abstract
European Society of Cardiology (ESC) guidelines gave class I A indication for use of DCB in in-stent restenosis. However, no indication exists for the usage of DCB in de novo lesions. Although the current generation DES offer excellent results, as we embark more complex lesions such as calcified lesion and chronic total occlusion, restenosis and stent thrombosis are higher and tend to increase within the years. There is increasing desire to leave nothing behind to abolish the risk of restenosis and stent thrombosis and hence the absorbable scaffolds were introduced, but with disappointing results. In addition, they take several years to be absorbed. Drug coated balloons offer an alternative to stents with no permanent implant of metal or polymer. They are already in use in in Europe and Asia and they have been approved for the first time in the United States for clinical trials specifically for restenotic lesions. There is emerging data in de novo lesions which have shown that DCB are noninferior and in some studies maybe even superior to current generation DES especially in small vessels. In this article, we provide a comprehensive review of the literature on this expanding technology focussing on the evidence in both re-stenotic and de novo lesions.
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Affiliation(s)
- Bernardo Cortese
- Fondazione Ricerca e Innovazione Cardiovascolare, Milano, Italy
- DCB Academy, Milano, Italy
- Cardioparc, Lyon, France
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Shi Q, Zhang B, Wang X, Fei J, Qin Q, Zheng B, Chen M. Safety and efficacy of a novel 3D-printed bioresorbable sirolimus-eluting scaffold in a porcine model. ASIAINTERVENTION 2023; 9:133-142. [PMID: 37736208 PMCID: PMC10507451 DOI: 10.4244/aij-d-22-00051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 12/19/2022] [Indexed: 09/23/2023]
Abstract
Background The effect of 3D-printed bioresorbable vascular scaffolds (BRS) in coronary heart disease has not been clarified. Aims We aimed to compare the safety and efficacy of 3D-printed BRS with that of metallic sirolimus-eluting stents (SES). Methods Thirty-two BRS and 32 SES were implanted into 64 porcine coronary arteries. Quantitative coronary angiography (QCA) and optical coherence tomography (OCT) were performed at 14, 28, 97, and 189 days post-implantation. Scanning electron microscopy (SEM) and histopathological analyses were performed at each assessment. Results All stents/scaffolds were successfully implanted. All animals survived for the duration of the study. QCA showed the two devices had a similar stent/scaffold-to-artery ratio and acute percent recoil. OCT showed the lumen area (LA) and scaffold/stent area (SA) of the BRS were significantly smaller than those of the SES at 14 and 28 days post-implantation (14-day LA: BRS vs SES 4.52±0.41 mm2 vs 5.69±1.11 mm2; p=0.03; 14-day SA: BRS vs SES 4.99±0.45 mm2 vs 6.11±1.06 mm2; p=0.03; 28-day LA: BRS vs SES 2.93±1.03 mm2 vs 4.82±0.74 mm2; p=0.003; 28-day SA: BRS vs SES 3.86±0.98 mm2 vs 5.75±0.71 mm2; p=0.03). Both the LA and SA of the BRS increased over time and were similar to those of the SES at the 97-day and 189-day assessments. SEM and histomorphological analyses showed no significant between-group differences in endothelialisation at each assessment. Conclusions The novel 3D-printed BRS showed safety and efficacy similar to that of SES in a porcine model. The BRS also showed a long-term positive remodelling effect.
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Affiliation(s)
- Qiuping Shi
- Department of Cardiology, Peking University First Hospital, Beijing, People's Republic of China
| | - Bin Zhang
- Department of Cardiology, Peking University First Hospital, Beijing, People's Republic of China
| | - Xingang Wang
- Department of Cardiology, Peking University First Hospital, Beijing, People's Republic of China
| | - Jintao Fei
- Department of Cardiology, Peking University First Hospital, Beijing, People's Republic of China
| | - Qiao Qin
- Department of Cardiology, Peking University First Hospital, Beijing, People's Republic of China
| | - Bo Zheng
- Department of Cardiology, Peking University First Hospital, Beijing, People's Republic of China
- Institute of Cardiovascular Disease, Peking University First Hospital, Beijing, People's Republic of China
| | - Ming Chen
- Department of Cardiology, Peking University First Hospital, Beijing, People's Republic of China
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Chen E, Xiong Z, Cai X, Liu S, Qin X, Sun J, Jin X, Sun K. Bioresorbable PPDO sliding-lock stents with optimized FDM parameters for congenital heart disease treatment. J Mech Behav Biomed Mater 2023; 138:105609. [PMID: 36525876 DOI: 10.1016/j.jmbbm.2022.105609] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 12/04/2022] [Accepted: 12/05/2022] [Indexed: 12/12/2022]
Abstract
Stent implantation has been a promising therapy for congenital heart disease (CHD) due to better efficacy. Compared to permanent metal stents, bioresorbable polymer stents have shown a great advantage in accommodating the vascular growth of pediatric patients, but the application is still limited due to inferior radial strength. Here, bioresorbable poly(p-dioxanone) (PPDO) sliding-lock stents for CHD treatment were fabricated by fused deposition modeling (FDM). The effects of FDM processing parameters, including nozzle temperature, bed temperature, layer thickness, and printing speed, on the mechanical properties of PPDO parts were investigated to optimize the processing condition to enhance the radial strength of stents. Finite element analysis (FEA) was also used to evaluate the mechanical properties of stents. PPDO sliding-lock stents fabricated under optimized FDM parameters showed radial strength of 3.315 ± 0.590 N/mm, superior to benchmark commercial metal stents. Radial strength curve and compression behavior of PPDO sliding-lock stents were investigated. Results of FEA exhibited that strut width, shape of the mesh cell and surface coverage ratio had an impact on the compression force of PPDO sliding-lock stents. PPDO sliding-lock stents fabricated with optimized FDM parameters show favorable mechanical performance and meet the requirement of CHD treatment.
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Affiliation(s)
- Enrong Chen
- Department of Pediatric Cardiology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Zhihui Xiong
- Institute of Medical Robotics, Shanghai Jiao Tong University, Shanghai, China
| | - Xiaorong Cai
- School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Shilong Liu
- School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Xiji Qin
- Department of Pediatric Cardiology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Jing Sun
- Department of Pediatric Cardiology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
| | - Xuejun Jin
- Institute of Medical Robotics, Shanghai Jiao Tong University, Shanghai, China.
| | - Kun Sun
- Department of Pediatric Cardiology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
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Morrish R, Corcoran R, Cooke J, Eesa M, Wong JH, Mitha AP. Fluoroscopy, CT, and MR imaging characteristics of a novel primarily bioresorbable flow-diverting stent for aneurysms. Interv Neuroradiol 2022; 28:660-667. [PMID: 34787481 PMCID: PMC9706267 DOI: 10.1177/15910199211060979] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Accepted: 09/18/2021] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Five to ten percent of the global population have unruptured intracranial aneurysms, and ruptured brain aneurysms cause approximately 500,000 deaths a year. Flow-diverting stent treatment is a less invasive intracranial aneurysm treatment that induces aneurysm thrombosis. The imaging characteristics of a novel primarily bioresorbable flow-diverting stent (BFDS) are assessed in comparison to the leading metal stent using fluoroscopy, CT, and MRI. METHODS X-ray/fluoroscopic images of stents were taken using a human cadaveric skull model. CT and MRI were acquired using silicone flow models of residual aneurysms. Images were analyzed with Likert scales in anonymous surveys by neurointerventionalists. Quantitative measurements of radiographic density (CT) and artifact boundary size (CT & MRI) were also obtained. RESULTS Visibility of the BFDS on X-ray was less than the metal stent but deemed adequate for deployment and intraprocedural assessment. The metal stent was more radiopaque than the BFDS on CT, but qualitative assessment was not significantly different for the two stents. MRI imaging was significantly better using the BFDS in terms of overall artifact and intraluminal assessment. CONCLUSIONS The BFDS has adequate visualization on X-ray/fluoroscopy and should be clinically acceptable for fluoroscopic deployment. On MRI, there is less quantitative artifact as well as overall improved qualitative assessment that will allow for more detailed non-invasive imaging follow-up of treated aneurysms, potentially reducing the need for digital subtraction catheter angiography.
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Affiliation(s)
- Rosalie Morrish
- Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
| | | | | | - Muneer Eesa
- Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
| | - John H Wong
- Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
| | - Alim P Mitha
- Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
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Rola P, Włodarczak S, Doroszko A, Lesiak M, Włodarczak A. The bioresorbable magnesium scaffold (Magmaris)-State of the art: From basic concept to clinical application. Catheter Cardiovasc Interv 2022; 100:1051-1058. [PMID: 36229949 DOI: 10.1002/ccd.30435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 09/07/2022] [Accepted: 10/02/2022] [Indexed: 11/08/2022]
Abstract
Since its introduction to clinical practice, coronary artery stent implantation has become a crucial part of the therapy of coronary artery disease (CAD). Despite the undeniable evolution of percutaneous coronary revascularization procedures, drug-eluting stent (DES) technology shows some limitations. To overcome these limitations bioresorbable vascular scaffolds (BRS) were designed as a vessel-supporting technology allowing for anatomical and functional restoration of the vessel after the scaffold intended resorption. Various materials have been proposed as the basis of the scaffold backbone. In this narrative review, we present second-generation magnesium-alloy bioresorbable scaffold devices (Magmaris; Biotronik). Additionally, we discuss available preclinical and clinical data regarding this new magnesium BRS.
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Affiliation(s)
- Piotr Rola
- Faculty of Health Science and Physical Culture, Witelon Collegium State University, Legnica, Poland.,Department of Cardiology, Provincial Specialized Hospital in Legnica, Legnica, Poland
| | - Szymon Włodarczak
- Department of Cardiology, The Copper Health Centre (MCZ), Lubin, Poland
| | - Adrian Doroszko
- Clinical Department of Internal and Occupational Diseases, Hypertension and Clinical Oncology, Wroclaw Medical University, Wrocław, Poland
| | - Maciej Lesiak
- 1st Department of Cardiology, Poznan University of Medical Sciences, Poznań, Poland
| | - Adrian Włodarczak
- Faculty of Health Science and Physical Culture, Witelon Collegium State University, Legnica, Poland.,Department of Cardiology, The Copper Health Centre (MCZ), Lubin, Poland
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InSilc Computational Tool for In Silico Optimization of Drug-Eluting Bioresorbable Vascular Scaffolds. COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2022; 2022:5311208. [PMID: 36105243 PMCID: PMC9467806 DOI: 10.1155/2022/5311208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 08/12/2022] [Accepted: 08/17/2022] [Indexed: 11/17/2022]
Abstract
Stents made by different manufacturers must meet the requirements of standard in vitro mechanical tests performed under different physiological conditions in order to be validated. In addition to in vitro research, there is a need for in silico numerical simulations that can help during the stent prototyping phase. In silico simulations have the ability to give the same stent responses as well as the potential to reduce costs and time needed to carry out experimental tests. The goal of this paper is to show the achievements of the computational platform created as a result of the EU-funded project InSilc, used for numerical testing of most standard tests for validation of preproduction bioresorbable vascular scaffolds (BVSs). Within the platform, an ad hoc simulation protocol has been developed based on the finite element (FE) analysis program PAK and user interface software CAD Field and Solid. Two different designs of two different stents have been numerically simulated using this integrated tool, and the results have been demonstrated. The following standard tests have been performed: longitudinal tensile strength, local compression, kinking, and flex 1-3. Strut thickness and additional pocket holes (slots) in two different scaffolds have been used as representative parameters for comparing the mechanical characteristics of the stents (AB-BVS vs. AB-BVS-thinner and PLLA-prot vs. PLLA-plot-slot). The AB-BVS-thinner prototype shows better overall stress distribution than the AB-BVS, while the PLLA-prot shows better overall stress distribution in comparison to the PLLA-plot-slot. In all cases, the values of the maximum effective stresses are below 220 MPa—the value obtained by in vitro experiment. Despite the presented results, additional considerations should be included before the proposed software can be used as a validation tool for stent prototyping.
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Current Status and Outlook of Temporary Implants (Magnesium/Zinc) in Cardiovascular Applications. METALS 2022. [DOI: 10.3390/met12060999] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Medical application materials must meet multiple requirements, and the designed material must mimic the structure, shape. and support the formation of the replacing tissue. Magnesium (Mg) and Zinc alloys (Zn), as a “smart” biodegradable material and as “the green engineering material in the 21st century”, have become an outstanding implant material due to their natural degradability, smart biocompatibility, and desirable mechanical properties. Magnesium and Zinc are recognized as the next generation of cardiovascular stents and bioresorbable scaffolds. At the same time, improving the properties and corrosion resistance of these alloys is an urgent challenge. particularly to promote the application of magnesium alloys. A relatively fast deterioration rate of magnesium-based materials generally results in premature mechanical integrity compromise and local hydrogen build-up, resulting in restricted applicability. This review article aims to give a comprehensive comparison between Zn-based alloys and Mg-based alloys, focusing primarily on degradation and biocompatibility for cardiovascular applications. The recent clinical trials using these biodegradable metals have also been addressed.
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Loffredo S, Gambaro S, Copes F, Paternoster C, Giguère N, Vedani M, Mantovani D. Effect of silver in thermal treatments of Fe-Mn-C degradable metals: Implications for stent processing. Bioact Mater 2022; 12:30-41. [PMID: 35087961 PMCID: PMC8777259 DOI: 10.1016/j.bioactmat.2021.10.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 04/15/2021] [Accepted: 10/18/2021] [Indexed: 11/26/2022] Open
Abstract
Twinning-induced plasticity (TWIP) steels are considered excellent materials for manufacturing products requiring extremely high mechanical properties for various applications including thin medical devices, such as biodegradable intravascular stents. It is also proven that the addition of Ag can guarantee an appropriate degradation while implanted in human body without affecting its bioactive properties. In order to develop an optimized manufacturing process for thin stents, the effect of Ag on the recrystallization behavior of TWIP steels needs to be elucidated. This is of major importance since manufacturing stents involves several intermediate recrystallization annealing treatments. In this work, the recrystallization mechanism of two Fe-Mn-C steels with and without Ag was thoroughly investigated by microstructural and mechanical analyses. It was observed that Ag promoted a finer microstructure with a different texture evolution, while the recrystallization kinetics resulted unaffected. The presence of Ag also reduced the effectiveness of the recrystallization treatment. This behavior was attributed to the presence of Ag-rich second phase particles, precipitation of carbides and to the preferential development of grains possessing a {111} orientation upon thermal treatment. The prominence of {111} grains can also give rise to premature twinning, explaining the role of Ag in reducing the ductility of TWIP steels already observed in other works. Furthermore, in vitro biological performances were unaffected by Ag. These findings could allow the design of efficient treatments for supporting the transformation of Fe-Mn-C steels alloyed with Ag into commercial products. Recrystallization of a TWIP steel is hampered by the presence of Ag and carbides. Ag promotes preferential formation of {111} grains during thermal treatments. Ag broadens the Schmid factor distribution, leading to a reduction in ductility. Ag does not affect cytotoxicity and hemocompatibility. Annealing treatment above 900 °C is required for the Fe-Mn-C-Ag system.
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Two-Step Geometry Design Method, Numerical Simulations and Experimental Studies of Bioresorbable Stents. MATERIALS 2022; 15:ma15072385. [PMID: 35407718 PMCID: PMC8999420 DOI: 10.3390/ma15072385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 03/17/2022] [Accepted: 03/20/2022] [Indexed: 11/16/2022]
Abstract
The stent-implantation process during angioplasty procedures usually involves clamping the stent onto a catheter to a size that allows delivery to the place inside the artery. Finding the right geometrical form of the stent to ensure good functionality in the open form and to enable the clamping process is one of the key elements in the stent-design process. In the first part of the work, an original two-step procedure for stent-geometry design was proposed. This was due to the necessary selection of a geometry that would provide adequate support to the blood-vessel wall without causing damage to the vessel. Numerical simulations of the crimping and deployment processes were performed to verify the method. At the end of this stage, the optimal stent was selected for further testing. In addition, numerical simulations of selected experimental tests (catheter-crimping process, compression process) were used to verify the obtained geometrical forms. The results of experimental tests on stents produced by the microinjection method are presented. The digital image correlation (DIC) method was used to compare the results of numerical simulation and experimental tests. The two-step modeling approach was found to help select the appropriate geometry of the expanded stent, which is an extremely important step in the design of the crimping process. In the part of the paper where the results obtained by numerical simulation were compared with those gained by experiment and using the DIC method, a good compatibility of the displacement results can be observed. For both longitudinal and transverse (pinch) stent compression, the results practically coincide. The paper presents also the application of the DIC method which significantly expands the research possibilities, allowing for a detailed inspection of the deformation state and, above all, verification of local dangerous areas. This approach significantly increases the possibility of assessing the quality of the stents.
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Loskot J, Jezbera D, Zmrhalová ZO, Nalezinková M, Alferi D, Lelkes K, Voda P, Andrýs R, Fučíková AM, Hosszú T, Bezrouk A. A Complex In Vitro Degradation Study on Polydioxanone Biliary Stents during a Clinically Relevant Period with the Focus on Raman Spectroscopy Validation. Polymers (Basel) 2022; 14:polym14050938. [PMID: 35267761 PMCID: PMC8912347 DOI: 10.3390/polym14050938] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 02/18/2022] [Accepted: 02/23/2022] [Indexed: 02/06/2023] Open
Abstract
Biodegradable biliary stents are promising treatments for biliary benign stenoses. One of the materials considered for their production is polydioxanone (PPDX), which could exhibit a suitable degradation time for use in biodegradable stents. Proper material degradation characteristics, such as sufficient stiffness and disintegration resistance maintained for a clinically relevant period, are necessary to ensure stent safety and efficacy. The hydrolytic degradation of commercially available polydioxanone biliary stents (ELLA-CS, Hradec Králové, Czech Republic) in phosphate-buffered saline (PBS) was studied. During 9 weeks of degradation, structural, physical, and surface changes were monitored using Raman spectroscopy, differential scanning calorimetry, scanning electron microscopy, and tensile and torsion tests. It was found that the changes in mechanical properties are related to the increase in the ratio of amorphous to crystalline phase, the so-called amorphicity. Monitoring the amorphicity using Raman spectroscopy has proven to be an appropriate method to assess polydioxanone biliary stent degradation. At the 1732 cm−1 Raman peak, the normalized shoulder area is less than 9 cm−1 which indicates stent disintegration. The stent disintegration started after 9 weeks of degradation in PBS, which agrees with previous in vitro studies on polydioxanone materials as well as with in vivo studies on polydioxanone biliary stents.
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Affiliation(s)
- Jan Loskot
- Department of Physics, University of Hradec Králové, Rokitanského 62, 500 03 Hradec Králové, Czech Republic; (J.L.); (D.J.)
| | - Daniel Jezbera
- Department of Physics, University of Hradec Králové, Rokitanského 62, 500 03 Hradec Králové, Czech Republic; (J.L.); (D.J.)
| | - Zuzana Olmrová Zmrhalová
- Center of Materials and Nanotechnologies, Faculty of Chemical Technology, University of Pardubice, Studentska 95, 530 02 Pardubice, Czech Republic;
| | - Martina Nalezinková
- Department of Biology, University of Hradec Králové, Rokitanského 62, 500 03 Hradec Králové, Czech Republic; (M.N.); (A.M.F.)
| | - Dino Alferi
- Department of Medical Biophysics, Faculty of Medicine in Hradec Králové, Charles University, Šimkova 870, 500 03 Hradec Králové, Czech Republic; (D.A.); (K.L.); (P.V.)
| | - Krisztina Lelkes
- Department of Medical Biophysics, Faculty of Medicine in Hradec Králové, Charles University, Šimkova 870, 500 03 Hradec Králové, Czech Republic; (D.A.); (K.L.); (P.V.)
| | - Petr Voda
- Department of Medical Biophysics, Faculty of Medicine in Hradec Králové, Charles University, Šimkova 870, 500 03 Hradec Králové, Czech Republic; (D.A.); (K.L.); (P.V.)
| | - Rudolf Andrýs
- Department of Chemistry, University of Hradec Králové, Rokitanského 62, 500 03 Hradec Králové, Czech Republic;
| | - Alena Myslivcová Fučíková
- Department of Biology, University of Hradec Králové, Rokitanského 62, 500 03 Hradec Králové, Czech Republic; (M.N.); (A.M.F.)
| | - Tomáš Hosszú
- Department of Neurosurgery, Faculty of Medicine in Hradec Králové, Charles University, Sokolská 581, 500 05 Hradec Králové, Czech Republic;
- Department of Neurosurgery, University Hospital Hradec Králové, Sokolská 581, 500 05 Hradec Králové, Czech Republic
| | - Aleš Bezrouk
- Department of Medical Biophysics, Faculty of Medicine in Hradec Králové, Charles University, Šimkova 870, 500 03 Hradec Králové, Czech Republic; (D.A.); (K.L.); (P.V.)
- Correspondence:
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13
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Zhao G, Liu J, Liu M, Tian Y, Cheng J, Liu W, Ni Z. Influence of parameters on mechanical properties of poly (L-lactic acid) helical stents. J Biomed Mater Res B Appl Biomater 2022; 110:1705-1712. [PMID: 35157351 DOI: 10.1002/jbm.b.35031] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 12/08/2021] [Accepted: 01/29/2022] [Indexed: 12/17/2022]
Abstract
With better biocompatibility, bioresorbable poly (L-lactic acid) (PLLA) helical stents are expected to replace the commonly used metallic stents. However, due to the great difference between the material properties of PLLA and those of metals, the current research results on mechanical properties of stents will not be applicative. In this article, the effects of i on the radial compression performance and bending stiffness of PLLA helical stents were systematically studied, and the effect of temperature on the radial compression performance of the helical stent was investigated. The findings obtained indicate that the reduction of initial pitch angle and initial diameter can enhance the radial compression performance. The reduction of initial pitch angle and the increase of initial diameter can weaken the bending stiffness of the helical stent. Moreover, the increase of temperature will reduce the radial stiffness and peak compression force of the helical stent. A favorable agreement between the theoretical and experimental results of radial compression properties was found in stents with the initial pitch angle between 14° and 21° and all initial diameters. This work can provide suggestions for the use of the theoretical formula in structure design of the helical stent.
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Affiliation(s)
- Gutian Zhao
- School of Mechanical Engineering, Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing, China
| | - Jiaming Liu
- School of Mechanical Engineering, Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing, China
| | - Muqing Liu
- School of Mechanical Engineering, Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing, China
| | - Yuan Tian
- School of Mechanical Engineering, Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing, China
| | - Jie Cheng
- School of Mechanical Engineering, Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing, China
| | - Wentao Liu
- School of Mechanical Engineering, Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing, China
| | - Zhonghua Ni
- School of Mechanical Engineering, Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing, China
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14
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Yanagisawa Y, Shimizu Y, Mukai T, Sano Y, Odashima K, Ikeo N, Saito H, Yamauchi K, Takahashi T, Kumamoto H. Biodegradation behaviors of magnesium(Mg)-based alloy nails in autologous bone grafts: In vivo study in rabbit skulls. J Appl Biomater Funct Mater 2022; 20:22808000221095230. [PMID: 35599624 DOI: 10.1177/22808000221095230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
OBJECTIVE In this study, autologous bone grafts using bone-fixing nails made of magnesium-zinc-calcium ternary alloys were performed using rabbit skulls. MATERIAL AND METHODS Two types of nails for bone fixation were prepared: 2.5 mm width, 3 mm length and 2.5 mm width, 2 mm length. A disk-shaped bone with a diameter of 5 mm was resected from the parietal bone and fixed with a 3 mm long nail. As a control group, a 2 mm long nail was driven into the existing bone. The rabbits were sacrificed at 1, 4, 12, and 24 weeks after surgery. The resected samples were observed with micro X-ray CT, and embedded in methyl methacrylate to prepare non-decalcified specimens. The in vivo localization of elements was examined using energy-dispersive X-ray spectroscopy (EDS). RESULTS Micro X-ray CT images of samples showed volume reduction due to degradation in both the bone graft and control groups. No significant difference in the amount of degradation between the two groups was observed, however characteristic degradation processes were observed in each group. The samples stained with alizarin red S showed amorphous areas around the nails, which were considered as corrosion products and contacted directly with the newly formed bones. EDS analysis showed that corrosion products were mainly composed of magnesium and oxygen at an early stage, while calcium and phosphorus were detected on the surface layer during the long-term observation. CONCLUSIONS The degradation speed of the magnesium alloy nails varied depending on the shapes of the nails and surrounding tissue conditions. A calcium phosphate layer was formed on the surface of magnesium alloy nails, suggesting that the degradation rate of the nail was slow.
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Affiliation(s)
- Yuta Yanagisawa
- Division of Oral and Maxillofacial Surgery, Department of Oral Medicine and Surgery, Tohoku University Graduate School of Dentistry, Sendai, Miyagi, Japan.,Division of Oral Pathology, Department of Oral Medicine and Surgery, Tohoku University Graduate School of Dentistry, Sendai, Miyagi, Japan
| | - Yoshinaka Shimizu
- Division of Oral Pathology, Department of Oral Medicine and Surgery, Tohoku University Graduate School of Dentistry, Sendai, Miyagi, Japan
| | - Toshiji Mukai
- Department of Mechanical Engineering, Kobe University, Kobe, Hyogo, Japan
| | - Yuya Sano
- Division of Oral Pathology, Department of Oral Medicine and Surgery, Tohoku University Graduate School of Dentistry, Sendai, Miyagi, Japan
| | - Kenji Odashima
- Division of Oral and Maxillofacial Surgery, Department of Oral Medicine and Surgery, Tohoku University Graduate School of Dentistry, Sendai, Miyagi, Japan.,Division of Oral Pathology, Department of Oral Medicine and Surgery, Tohoku University Graduate School of Dentistry, Sendai, Miyagi, Japan
| | - Naoko Ikeo
- Department of Mechanical Engineering, Kobe University, Kobe, Hyogo, Japan
| | - Haruka Saito
- Division of Oral Pathology, Department of Oral Medicine and Surgery, Tohoku University Graduate School of Dentistry, Sendai, Miyagi, Japan
| | - Kensuke Yamauchi
- Division of Oral and Maxillofacial Surgery, Department of Oral Medicine and Surgery, Tohoku University Graduate School of Dentistry, Sendai, Miyagi, Japan
| | - Tetsu Takahashi
- Division of Oral and Maxillofacial Surgery, Department of Oral Medicine and Surgery, Tohoku University Graduate School of Dentistry, Sendai, Miyagi, Japan
| | - Hiroyuki Kumamoto
- Division of Oral Pathology, Department of Oral Medicine and Surgery, Tohoku University Graduate School of Dentistry, Sendai, Miyagi, Japan
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15
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İbişoğlu E, Çakal S, Çakal B, Güneş HM, Boyraz B, Boztosun B. Long-term results of long segment coronary artery lesions overlapped with novolimus-eluting DESolve scaffold: Disappointment or futuristic? Anatol J Cardiol 2021; 25:912-919. [PMID: 34866586 DOI: 10.5152/anatoljcardiol.2021.25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVE The data on using novolimus-eluting DESolve bioresorbable scaffolds (BVS) for long-segment coronary artery lesions remains insufficient. In this study, our main objective was to assess the long-term effects of the overlapping applications of both DESolve-DESolve and the drug-eluting stent (DES)-DESolve. METHODS A single-centered study of 103 patients scheduled for DESolve placement for long-segment lesions (>28 mm) was conducted (October 2013 to November 2016). A DESolve-DESolve overlap was used on 43 patients and a DES-DESolve overlap on 60 patients. Acute procedural success and major adverse cardiac events (MACE) (stent thrombosis, targeted vessel revascularization, targeted lesion revascularization, and cardiac death) were evaluated. The patients were followed up for 48 months. RESULTS Revascularization was performed on 4 (6.7%) patients in the DES-DESolve group and 5 (11.6%) patients in the DESolve-DESolve group for target lesion revascularization. Among the study population, 10 (9.7%) patients had MACE, including 5 (8.3%) patients in the DES-DESolve group and 5 (11.6%) patients in the DESolve-DESolve group. CONCLUSION The positive results of our study concerning the use of DESolve for the treatment of long coronary lesions demonstrate that BVS will emerge with new platforms and become non-inferior to the DES.
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Affiliation(s)
- Ersin İbişoğlu
- Department of Cardiology, Başakşehir Çam and Sakura City Hospital; İstanbul-Turkey
| | - Sinem Çakal
- Department of Cardiology, İstanbul Haseki Training and Research Hospital; İstanbul-Turkey
| | - Beytullah Çakal
- Department of Cardiology, İstanbul Medipol University; İstanbul-Turkey
| | - H Murat Güneş
- Department of Cardiology, İstanbul Medipol University; İstanbul-Turkey
| | | | - Bilal Boztosun
- Department of Cardiology, İstanbul Medipol University; İstanbul-Turkey
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16
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Wegner N, Klein M, Scholz R, Kotzem D, Macias Barrientos M, Walther F. Mechanical in vitro fatigue testing of implant materials and components using advanced characterization techniques. J Biomed Mater Res B Appl Biomater 2021; 110:898-909. [PMID: 34846806 DOI: 10.1002/jbm.b.34970] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 08/03/2021] [Accepted: 11/13/2021] [Indexed: 01/01/2023]
Abstract
Implants of different material classes have been used for the reconstruction of damaged hard and soft tissue for decades. The aim is to increase and subsequently maintain the patient's quality of life through implantation. In service, most implants are subjected to cyclic loading, which must be taken particularly into consideration, since the fatigue strength is far below the yield and tensile strength. Inaccurate estimation of the structural strength of implants due to the consideration of yield or tensile strength leads to a miscalculation of the implant's fatigue strength and lifetime, and therefore, to its unexpected early fatigue failure. Thus, fatigue failure of an implant based on overestimated performance capability represents acute danger to human health. The determination of fatigue strength by corresponding tests investigating various stress amplitudes is time-consuming and cost-intensive. This study summarizes four investigation series on the fatigue behavior of different implant materials and components, following a standard and an in vitro short-time testing procedure, which evaluates the material reaction in one enhanced test set-up. The test set-up and the applied characterization methods were adapted to the respective application of the implant with the aim to simulate the surrounding of the human body with laboratory in vitro tests only. It could be shown that by using the short-time testing method the number of tests required to determine the fatigue strength can be drastically reduced. In future, therefore it will be possible to exclude unsuitable implant materials or components before further clinical investigations by using a time-efficient and application-oriented testing method.
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Affiliation(s)
- Nils Wegner
- Chair of Materials Test Engineering (WPT), TU Dortmund University, Dortmund, Germany
| | - Martin Klein
- Chair of Materials Test Engineering (WPT), TU Dortmund University, Dortmund, Germany
| | - Ronja Scholz
- Chair of Materials Test Engineering (WPT), TU Dortmund University, Dortmund, Germany
| | - Daniel Kotzem
- Chair of Materials Test Engineering (WPT), TU Dortmund University, Dortmund, Germany
| | | | - Frank Walther
- Chair of Materials Test Engineering (WPT), TU Dortmund University, Dortmund, Germany
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17
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Khalaj R, Tabriz AG, Okereke MI, Douroumis D. 3D printing advances in the development of stents. Int J Pharm 2021; 609:121153. [PMID: 34624441 DOI: 10.1016/j.ijpharm.2021.121153] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Revised: 09/28/2021] [Accepted: 09/29/2021] [Indexed: 02/07/2023]
Abstract
3D printing technologies have found several applications within the biomedical sector including in the fabrication of medical devices, advanced visualization, diagnosis planning and simulation of surgical procedures. One of the areas in which of 3D printing is anticipated to revolutionised is the manufacturing of implantable bioresorbable drug-eluting scaffolds (stents). The ability to customize and create personalised tailor-made bioresorbable scaffolds has the potential to help solve many of the challenges associated with stenting, such as inappropriate stent sizing and design, abolish late stent thrombosis and help artery growth; 3D printing offers a rapid prototyping and effective method of producing stents making customization of designs feasible. This review provides an overview of the subjects and summarizes the latest research in the 3D printing technologies employed for the design and fabrication of bioresorbable stents including materials with the required printable and mechanical properties. Finally, we present a regulatory perspective on the development and engineering of 3D printed implantable stents.
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Affiliation(s)
- Roxanne Khalaj
- School of Science, University of Greenwich, Central Avenue, Chatham Maritime, Chatham, Kent ME4 4TB, UK; CIPER Centre for Innovation and Process Engineering Research, Kent ME4 4TB, UK
| | - Atabak Ghanizadeh Tabriz
- School of Science, University of Greenwich, Central Avenue, Chatham Maritime, Chatham, Kent ME4 4TB, UK; CIPER Centre for Innovation and Process Engineering Research, Kent ME4 4TB, UK
| | - Michael I Okereke
- Mathematical Modelling for Engineering Research Group, Department of Engineering Science, University of Greenwich, UK
| | - Dennis Douroumis
- School of Science, University of Greenwich, Central Avenue, Chatham Maritime, Chatham, Kent ME4 4TB, UK; CIPER Centre for Innovation and Process Engineering Research, Kent ME4 4TB, UK.
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18
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Tidwell K, Harriet S, Barot V, Bauer A, Vaughan MB, Hossan MR. Design and Analysis of a Biodegradable Polycaprolactone Flow Diverting Stent for Brain Aneurysms. Bioengineering (Basel) 2021; 8:bioengineering8110183. [PMID: 34821749 PMCID: PMC8614946 DOI: 10.3390/bioengineering8110183] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 10/31/2021] [Accepted: 11/09/2021] [Indexed: 11/21/2022] Open
Abstract
The flow diverting stent (FDS) has become a promising endovascular device for the treatment of aneurysms. This research presents a novel biodegradable and non-braided Polycaprolactone (PCL) FDS. The PCL FDS was designed and developed using an in-house fabrication unit and coated on two ends with BaSO4 for angiographic visibility. The mechanical flexibility and quality of FDS surfaces were examined with the UniVert testing machine, scanning electron microscope (SEM), and 3D profilometer. Human umbilical vein endothelial cell (HUVEC) adhesion, proliferation, and cell morphology studies on PCL FDS were performed. The cytotoxicity and NO production by HUVECs with PCL FDS were also conducted. The longitudinal tensile, radial, and bending flexibility were found to be 1.20 ± 0.19 N/mm, 0.56 ± 0.11 N/mm, and 0.34 ± 0.03 N/mm, respectively. The FDS was returned to the original shape and diameter after repeated compression and bending without compromising mechanical integrity. Results also showed that the proliferation and adhesion of HUVECs on the FDS surface increased over time compared to control without FDS. Lactate dehydrogenase (LDH) release and NO production showed that PCL FDS were non-toxic and satisfactory. Cell morphology studies showed that HUVECs were elongated to cover the FD surface and developed an endothelial monolayer. This study is a step forward toward the development and clinical use of biodegradable flow diverting stents for endovascular treatment of the aneurysm.
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Affiliation(s)
- Kaitlyn Tidwell
- Department of Engineering and Physics, University of Central Oklahoma, Edmond, OK 73034, USA; (K.T.); (S.H.); (V.B.)
| | - Seth Harriet
- Department of Engineering and Physics, University of Central Oklahoma, Edmond, OK 73034, USA; (K.T.); (S.H.); (V.B.)
| | - Vishal Barot
- Department of Engineering and Physics, University of Central Oklahoma, Edmond, OK 73034, USA; (K.T.); (S.H.); (V.B.)
| | - Andrew Bauer
- Department of Neurosurgery, University of Oklahoma-Health Science Center, Oklahoma City, OK 73104, USA;
| | - Melville B. Vaughan
- Department of Biology, University of Central Oklahoma, Edmond, OK 73034, USA;
- Center of Interdisciplinary Biomedical Education and Research, University of Central Oklahoma, Edmond, OK 73034, USA
| | - Mohammad R. Hossan
- Department of Engineering and Physics, University of Central Oklahoma, Edmond, OK 73034, USA; (K.T.); (S.H.); (V.B.)
- Center of Interdisciplinary Biomedical Education and Research, University of Central Oklahoma, Edmond, OK 73034, USA
- Correspondence: ; Tel.: +1-405-975-5295
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19
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Milosevic M, Anic M, Nikolic D, Geroski V, Milicevic B, Kojic M, Filipovic N. Application of in silico Platform for the Development and Optimization of Fully Bioresorbable Vascular Scaffold Designs. FRONTIERS IN MEDICAL TECHNOLOGY 2021; 3:724062. [PMID: 35047953 PMCID: PMC8757700 DOI: 10.3389/fmedt.2021.724062] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 09/08/2021] [Indexed: 11/29/2022] Open
Abstract
Bioresorbable vascular scaffolds (BVS), made either from polymers or from metals, are promising materials for treating coronary artery disease through the processes of percutaneous transluminal coronary angioplasty. Despite the opinion that bioresorbable polymers are more promising for coronary stents, their long-term advantages over metallic alloys have not yet been demonstrated. The development of new polymer-based BVS or optimization of the existing ones requires engineers to perform many very expensive mechanical tests to identify optimal structural geometry and material characteristics. in silico mechanical testing opens the possibility for a fast and low-cost process of analysis of all the mechanical characteristics and also provides the possibility to compare two or more competing designs. In this study, we used a recently introduced material model of poly-l-lactic acid (PLLA) fully bioresorbable vascular scaffold and recently empowered numerical InSilc platform to perform in silico mechanicals tests of two different stent designs with different material and geometrical characteristics. The result of inflation, radial compression, three-point bending, and two-plate crush tests shows that numerical procedures with true experimental constitutive relationships could provide reliable conclusions and a significant contribution to the optimization and design of bioresorbable polymer-based stents.
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Affiliation(s)
- Miljan Milosevic
- Bioengineering Research and Development Center, BioIRC, Kragujevac, Serbia
- Institute for Information Technologies, University of Kragujevac, Kragujevac, Serbia
- Faculty of Information Technologies, Belgrade Metropolitan University, Belgrade, Serbia
| | - Milos Anic
- Bioengineering Research and Development Center, BioIRC, Kragujevac, Serbia
- Faculty of Engineering, University of Kragujevac, Kragujevac, Serbia
| | - Dalibor Nikolic
- Bioengineering Research and Development Center, BioIRC, Kragujevac, Serbia
- Institute for Information Technologies, University of Kragujevac, Kragujevac, Serbia
| | - Vladimir Geroski
- Bioengineering Research and Development Center, BioIRC, Kragujevac, Serbia
- Faculty of Engineering, University of Kragujevac, Kragujevac, Serbia
| | - Bogdan Milicevic
- Bioengineering Research and Development Center, BioIRC, Kragujevac, Serbia
- Faculty of Engineering, University of Kragujevac, Kragujevac, Serbia
| | - Milos Kojic
- Bioengineering Research and Development Center, BioIRC, Kragujevac, Serbia
- Department of Nanomedicine, Houston Methodist Research Institute, Houston, TX, United States
- Serbian Academy of Sciences and Arts, Belgrade, Serbia
| | - Nenad Filipovic
- Bioengineering Research and Development Center, BioIRC, Kragujevac, Serbia
- Faculty of Engineering, University of Kragujevac, Kragujevac, Serbia
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20
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Kirillova A, Yeazel TR, Asheghali D, Petersen SR, Dort S, Gall K, Becker ML. Fabrication of Biomedical Scaffolds Using Biodegradable Polymers. Chem Rev 2021; 121:11238-11304. [PMID: 33856196 DOI: 10.1021/acs.chemrev.0c01200] [Citation(s) in RCA: 89] [Impact Index Per Article: 29.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Degradable polymers are used widely in tissue engineering and regenerative medicine. Maturing capabilities in additive manufacturing coupled with advances in orthogonal chemical functionalization methodologies have enabled a rapid evolution of defect-specific form factors and strategies for designing and creating bioactive scaffolds. However, these defect-specific scaffolds, especially when utilizing degradable polymers as the base material, present processing challenges that are distinct and unique from other classes of materials. The goal of this review is to provide a guide for the fabrication of biodegradable polymer-based scaffolds that includes the complete pathway starting from selecting materials, choosing the correct fabrication method, and considering the requirements for tissue specific applications of the scaffold.
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Affiliation(s)
- Alina Kirillova
- Thomas Lord Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708, United States
| | - Taylor R Yeazel
- Thomas Lord Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708, United States
| | - Darya Asheghali
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Shannon R Petersen
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Sophia Dort
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Ken Gall
- Thomas Lord Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708, United States
| | - Matthew L Becker
- Thomas Lord Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708, United States.,Department of Chemistry, Duke University, Durham, North Carolina 27708, United States.,Departments of Biomedical Engineering and Orthopaedic Surgery, Duke University, Durham, North Carolina 27708, United States
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21
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Cockerill I, See CW, Young ML, Wang Y, Zhu D. Designing Better Cardiovascular Stent Materials - A Learning Curve. ADVANCED FUNCTIONAL MATERIALS 2021; 31:2005361. [PMID: 33708033 PMCID: PMC7942182 DOI: 10.1002/adfm.202005361] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Indexed: 05/07/2023]
Abstract
Cardiovascular stents are life-saving devices and one of the top 10 medical breakthroughs of the 21st century. Decades of research and clinical trials have taught us about the effects of material (metal or polymer), design (geometry, strut thickness, and the number of connectors), and drug-elution on vasculature mechanics, hemocompatibility, biocompatibility, and patient health. Recently developed novel bioresorbable stents are intended to overcome common issues of chronic inflammation, in-stent restenosis, and stent thrombosis associated with permanent stents, but there is still much to learn. Increased knowledge and advanced methods in material processing have led to new stent formulations aimed at improving the performance of their predecessors but often comes with potential tradeoffs. This review aims to discuss the advantages and disadvantages of stent material interactions with the host within five areas of contrasting characteristics, such as 1) metal or polymer, 2) bioresorbable or permanent, 3) drug elution or no drug elution, 4) bare or surface-modified, and 5) self-expanding or balloon-expanding perspectives, as they relate to pre-clinical and clinical outcomes and concludes with directions for future studies.
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Affiliation(s)
- Irsalan Cockerill
- Department of Biomedical Engineering, University of North Texas, Denton, TX 76207, USA
- Department of Materials Science and Engineering, University of North Texas, Denton, TX 76207, USA
| | - Carmine Wang See
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY 11794, USA
| | - Marcus L. Young
- Department of Materials Science and Engineering, University of North Texas, Denton, TX 76207, USA
| | - Yadong Wang
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, USA
| | - Donghui Zhu
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY 11794, USA
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22
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Yeazel TR, Becker ML. Advancing Toward 3D Printing of Bioresorbable Shape Memory Polymer Stents. Biomacromolecules 2020; 21:3957-3965. [PMID: 32924443 DOI: 10.1021/acs.biomac.0c01082] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Stents have evolved significantly since their introduction to the medical field in the early 1980s, becoming widely used in percutaneous coronary interventions and following nephrological procedures. However, the current commercially available stents do not degrade and remain in the body forever, leading to problems like restenosis in cardiovascular applications or requiring removal procedures in ureteral applications. Efforts to replace metal with resorbable materials have largely been halted after the commercial failure of and safety concerns elicited by Abbott's Absorb stent in 2017. Industry continues to use common polymers such as poly(l-lactide) (PLLA) and polycaprolactone (PCL) for biomedical products, but due to the weak mechanical properties of these bioresorbable materials in comparison to metals, these devices have struggled to accomplish the goals set, increasing risk of thrombosis. 3D printing stents using bioresorbable and shape memory materials could provide a method of patient-personalized production, remove the need for balloon expansion, and limit stent migration, thus bringing a new age of stent technology. The investigation of a range of 3D-printable and bioresorbable shape-memory polymers can provide solutions to the shortcomings of previously explored bioresorbable stents and revitalize the medical device industry efforts into advancing stent technology.
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Affiliation(s)
- Taylor R Yeazel
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708, United States
| | - Matthew L Becker
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708, United States.,Departments of Chemistry, Biomedical Engineering, Orthopaedic Surgery, Duke University, Durham, North Carolina 27708, United States
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23
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Pacharra S, McMahon S, Duffy P, Basnett P, Yu W, Seisel S, Stervbo U, Babel N, Roy I, Viebahn R, Wang W, Salber J. Cytocompatibility Evaluation of a Novel Series of PEG-Functionalized Lactide-Caprolactone Copolymer Biomaterials for Cardiovascular Applications. Front Bioeng Biotechnol 2020; 8:991. [PMID: 32903548 PMCID: PMC7438451 DOI: 10.3389/fbioe.2020.00991] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 07/29/2020] [Indexed: 11/24/2022] Open
Abstract
Although the use of bioresorbable materials in stent production is thought to improve long-term safety compared to their durable counterparts, a recent FDA report on the 2-year follow-up of the first FDA-approved bioresorbable vascular stent showed an increased occurrence of major adverse cardiac events and thrombosis in comparison to the metallic control. In order to overcome the issues of first generation bioresorbable polymers, a series of polyethylene glycol-functionalized poly-L-lactide-co-ε-caprolactone copolymers with varying lactide-to-caprolactone content is developed using a novel one-step PEG-functionalization and copolymerization strategy. This approach represents a new facile way toward surface enhancement for cellular interaction, which is shown by screening these materials regarding their cyto- and hemocompatibility in terms of cytotoxicity, hemolysis, platelet adhesion, leucocyte activation and endothelial cell adhesion. By varying the lactide-to-caprolactone polymer composition, it is possible to gradually affect endothelial and platelet adhesion which allows fine-tuning of the biological response based on polymer chemistry. All polymers developed were non-cytotoxic, had acceptable leucocyte activation levels and presented non-hemolytic (<2% hemolysis rate) behavior except for PLCL-PEG 55:45 which presented hemolysis rate of 2.5% ± 0.5. Water contact angles were reduced in the polymers containing PEG functionalization (PLLA-PEG: 69.8° ± 2.3, PCL-PEG: 61.2° ± 7.5) versus those without (PLLA: 79.5° ± 3.2, PCL: 76.4° ± 10.2) while the materials PCL-PEG550, PLCL-PEG550 90:10 and PLCL-PEG550 70:30 demonstrated best endothelial cell adhesion. PLLA-PEG550 and PLCL-PEG550 70:30 presented as best candidates for cardiovascular implant use from a cytocompatibility perspective across the spectrum of testing completed. Altogether, these polymers are excellent innovative materials suited for an application in stent manufacture due to the ease in translation of this one-step synthesis strategy to device production and their excellent in vitro cyto- and hemocompatibility.
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Affiliation(s)
- Sandra Pacharra
- Salber Laboratory, Centre for Clinical Research, Department of Experimental Surgery, Ruhr-Universität Bochum, Bochum, Germany
| | - Seán McMahon
- Laboratory A, Synergy Centre, Ashland Specialties Ireland Ltd., Dublin, Ireland
| | - Patrick Duffy
- Laboratory A, Synergy Centre, Ashland Specialties Ireland Ltd., Dublin, Ireland
| | - Pooja Basnett
- School of Life Sciences, College of Liberal Arts and Sciences, University of Westminster, London, United Kingdom
| | - Wenfa Yu
- Rosenhahn Group, Faculty of Chemistry and Biochemistry, Analytical Chemistry - Biointerfaces, Ruhr-Universität Bochum, Bochum, Germany
| | - Sabine Seisel
- Faculty of Chemistry and Biochemistry, Analytical Chemistry - Center for Electrochemical Sciences, Ruhr-Universität Bochum, Bochum, Germany
| | - Ulrik Stervbo
- Centre for Translational Medicine, Medical Department I, Marien Hospital Herne, University Hospital of the Ruhr-University Bochum, Herne, Germany
| | - Nina Babel
- Centre for Translational Medicine, Medical Department I, Marien Hospital Herne, University Hospital of the Ruhr-University Bochum, Herne, Germany
| | - Ipsita Roy
- Roy Group, Kroto Innovation Centre, Department of Materials Science and Engineering, University of Sheffield, Sheffield, United Kingdom
| | - Richard Viebahn
- Department of Surgery, Universitätsklinikum Knappschaftskrankenhaus Bochum GmbH, Bochum, Germany
| | - Wenxin Wang
- The Charles Institute of Dermatology, School of Medicine and Medical Science, University College Dublin, Dublin, Ireland
| | - Jochen Salber
- Salber Laboratory, Centre for Clinical Research, Department of Experimental Surgery, Ruhr-Universität Bochum, Bochum, Germany.,Department of Surgery, Universitätsklinikum Knappschaftskrankenhaus Bochum GmbH, Bochum, Germany
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PENG KUN, QIAO AIKE, WANG JUNJIE, OHTA MAKOTO, CUI XINYANG, MU YONGLIANG. A NOVEL STRUCTURE DESIGN OF BIODEGRADABLE ZINC ALLOY STENT AND ITS EFFECTS ON RESHAPING STENOTIC VESSEL. J MECH MED BIOL 2020. [DOI: 10.1142/s0219519420500220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Biodegradable zinc alloy stents offer a prospective solution to mitigate incompatibility between artery and permanent stents. However, biodegradable stents are restricted in clinical therapy mainly because of their insufficient support for opening of stenotic vessel. As an effort to resolve this challenging problem, a novel structure of zinc alloy stent which significantly enhanced scaffold performance is proposed in this paper. Subsequently, the functionality of the new stent on reshaping vessels with 40% of stenosis was investigated in contrast with a common stent via finite element analysis. The simulation results show that radial recoiling ratio and dog-boning ratio of the new stent are decreased by 43.2% and 16.3%, respectively, compared with those of the common stent. A larger and flatter lumen is found in the plaque-vessel system deployed with the new stent. It suggests that the geometry of stent has strong influence on its mechanical performance. With strong scaffold capability and brilliant effect on reshaping stenotic vessel, the biodegradable zinc alloy stent-based novel structure is highly promised to be an alternative choice in interventional surgeries.
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Affiliation(s)
- KUN PENG
- Beijing University of Technology, Beijing 100124, P. R. China
| | - AIKE QIAO
- Beijing University of Technology, Beijing 100124, P. R. China
- College of Life Science and Bioengineering, Beijing University of Technology, No.100, Pingleyuan, Chaoyang District, Beijing 100124, P. R. China
| | - JUNJIE WANG
- Beijing University of Technology, Beijing 100124, P. R. China
| | - MAKOTO OHTA
- Tohoku University, Sendai, Miyagi 980-8577, Japan
| | - XINYANG CUI
- Beijing University of Technology, Beijing 100124, P. R. China
| | - YONGLIANG MU
- Northeastern University, Shenyang, Liaoning 110819, P. R. China
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Pellicano M, Di Gioia G, Ciccarelli G, Xaplanteris P, Delrue L, Toth GG, Van Durme F, Heyse A, Wyffels E, Vanderheyden M, Bartunek J, De Bruyne B, Barbato E. Procedural microvascular activation in long lesions treated with bioresorbable vascular scaffolds or everolimus-eluting stents: the PROACTIVE trial. EUROINTERVENTION 2020; 16:e147-e154. [PMID: 31085503 DOI: 10.4244/eij-d-18-01138] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
AIMS Significant platelet activation after long stented coronary segments has been associated with periprocedural microvascular impairment and myonecrosis. In long lesions treated either with an everolimus-eluting bioresorbable vascular scaffold (BVS) or an everolimus-eluting stent (EES), we aimed to investigate (a) procedure-related microvascular impairment, and (b) the relationship of platelet activation with microvascular function and related myonecrosis. METHODS AND RESULTS Patients (n=66) undergoing elective percutaneous coronary intervention (PCI) in long lesions were randomised 1:1 to either BVS or EES. The primary endpoint was the difference between groups in changes of pressure-derived corrected index of microvascular resistance (cIMR) after PCI. Periprocedural myonecrosis was assessed by high-sensitivity cardiac troponin T (hs-cTnT), platelet reactivity by high-sensitivity adenosine diphosphate (hs-ADP)-induced platelet reactivity with the Multiplate Analyzer. Post-dilatation was more frequent in the BVS group, with consequent longer procedure time. A significant difference was observed between the two groups in the primary endpoint of ΔcIMR (p=0.04). hs-ADP was not different between the groups at different time points. hs-cTnT significantly increased after PCI, without difference between the groups. CONCLUSIONS In long lesions, BVS implantation is associated with significant acute reduction in IMR as compared with EES, with no significant interaction with platelet reactivity or periprocedural myonecrosis.
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26
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Toong DWY, Toh HW, Ng JCK, Wong PEH, Leo HL, Venkatraman S, Tan LP, Ang HY, Huang Y. Bioresorbable Polymeric Scaffold in Cardiovascular Applications. Int J Mol Sci 2020; 21:E3444. [PMID: 32414114 PMCID: PMC7279389 DOI: 10.3390/ijms21103444] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 05/06/2020] [Accepted: 05/08/2020] [Indexed: 12/12/2022] Open
Abstract
Advances in material science and innovative medical technologies have allowed the development of less invasive interventional procedures for deploying implant devices, including scaffolds for cardiac tissue engineering. Biodegradable materials (e.g., resorbable polymers) are employed in devices that are only needed for a transient period. In the case of coronary stents, the device is only required for 6-8 months before positive remodelling takes place. Hence, biodegradable polymeric stents have been considered to promote this positive remodelling and eliminate the issue of permanent caging of the vessel. In tissue engineering, the role of the scaffold is to support favourable cell-scaffold interaction to stimulate formation of functional tissue. The ideal outcome is for the cells to produce their own extracellular matrix over time and eventually replace the implanted scaffold or tissue engineered construct. Synthetic biodegradable polymers are the favoured candidates as scaffolds, because their degradation rates can be manipulated over a broad time scale, and they may be functionalised easily. This review presents an overview of coronary heart disease, the limitations of current interventions and how biomaterials can be used to potentially circumvent these shortcomings in bioresorbable stents, vascular grafts and cardiac patches. The material specifications, type of polymers used, current progress and future challenges for each application will be discussed in this manuscript.
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Affiliation(s)
- Daniel Wee Yee Toong
- School of Materials Science and Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798, Singapore; (D.W.Y.T.); (L.P.T.)
| | - Han Wei Toh
- National Heart Centre Singapore, 5 Hospital Drive, Singapore 169609, Singapore; (H.W.T.); (J.C.K.N.); (P.E.H.W.)
- Department of Biomedical Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117583, Singapore;
| | - Jaryl Chen Koon Ng
- National Heart Centre Singapore, 5 Hospital Drive, Singapore 169609, Singapore; (H.W.T.); (J.C.K.N.); (P.E.H.W.)
- Department of Biomedical Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117583, Singapore;
| | - Philip En Hou Wong
- National Heart Centre Singapore, 5 Hospital Drive, Singapore 169609, Singapore; (H.W.T.); (J.C.K.N.); (P.E.H.W.)
- Duke-NUS Medical School, National University of Singapore, 8 College Road, Singapore 169857, Singapore
| | - Hwa Liang Leo
- Department of Biomedical Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117583, Singapore;
| | - Subramanian Venkatraman
- Materials Science and Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117575, Singapore;
| | - Lay Poh Tan
- School of Materials Science and Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798, Singapore; (D.W.Y.T.); (L.P.T.)
| | - Hui Ying Ang
- National Heart Centre Singapore, 5 Hospital Drive, Singapore 169609, Singapore; (H.W.T.); (J.C.K.N.); (P.E.H.W.)
- Department of Biomedical Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117583, Singapore;
| | - Yingying Huang
- School of Materials Science and Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798, Singapore; (D.W.Y.T.); (L.P.T.)
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Bukala J, Buszman PP, Małachowski J, Mazurkiewicz L, Sybilski K. Experimental Tests, FEM Constitutive Modeling and Validation of PLGA Bioresorbable Polymer for Stent Applications. MATERIALS 2020; 13:ma13082003. [PMID: 32344744 PMCID: PMC7215386 DOI: 10.3390/ma13082003] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 04/20/2020] [Accepted: 04/21/2020] [Indexed: 02/04/2023]
Abstract
The use of bioresorbable polymers such as poly(lactic-co-glycolic acid) (PLGA) in coronary stents can hypothetically reduce the risk of complications (e.g., restenosis, thrombosis) after percutaneous coronary intervention. However, there is a need for a constitutive modeling strategy that combines the simplicity of implementation with strain rate dependency. Here, a constitutive modeling methodology for PLGA comprising numerical simulation using a finite element method is presented. First, the methodology and results of PLGA experimental tests are presented, with a focus on tension tests of tubular-type specimens with different strain rates. Subsequently, the constitutive modeling methodology is proposed and described. Material model constants are determined based on the results of the experimental tests. Finally, the developed methodology is validated by experimental and numerical comparisons of stent free compression tests with various compression speeds. The validation results show acceptable correlation in terms of both quality and quantity. The proposed and validated constitutive modeling approach for the bioresorbable polymer provides a useful tool for the design and evaluation of bioresorbable stents.
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Affiliation(s)
- Jakub Bukala
- Institute of Mechanics and Computational Engineering, Faculty of Mechanical Engineering, Military University of Technology, Gen. Sylwestra Kaliskiego 2, 00-908 Warsaw, Poland; (J.B.); (L.M.); (K.S.)
| | - Piotr P. Buszman
- Center for Cardiovascular Research and Development American Heart of Poland, Czajek 41, 40-534 Katowice, Poland;
- Department of Cardiology, Andrzej Frycz-Modrzewski Kraków University, Gustawa Herlinga-Grudzińskiego 1, 30-705 Cracow, Poland
| | - Jerzy Małachowski
- Institute of Mechanics and Computational Engineering, Faculty of Mechanical Engineering, Military University of Technology, Gen. Sylwestra Kaliskiego 2, 00-908 Warsaw, Poland; (J.B.); (L.M.); (K.S.)
- Correspondence: ; Tel.: +48-261-839-140
| | - Lukasz Mazurkiewicz
- Institute of Mechanics and Computational Engineering, Faculty of Mechanical Engineering, Military University of Technology, Gen. Sylwestra Kaliskiego 2, 00-908 Warsaw, Poland; (J.B.); (L.M.); (K.S.)
| | - Kamil Sybilski
- Institute of Mechanics and Computational Engineering, Faculty of Mechanical Engineering, Military University of Technology, Gen. Sylwestra Kaliskiego 2, 00-908 Warsaw, Poland; (J.B.); (L.M.); (K.S.)
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28
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Beshchasna N, Saqib M, Kraskiewicz H, Wasyluk Ł, Kuzmin O, Duta OC, Ficai D, Ghizdavet Z, Marin A, Ficai A, Sun Z, Pichugin VF, Opitz J, Andronescu E. Recent Advances in Manufacturing Innovative Stents. Pharmaceutics 2020; 12:E349. [PMID: 32294908 PMCID: PMC7238261 DOI: 10.3390/pharmaceutics12040349] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Revised: 04/09/2020] [Accepted: 04/10/2020] [Indexed: 02/07/2023] Open
Abstract
Cardiovascular diseases are the most distributed cause of death worldwide. Stenting of arteries as a percutaneous transluminal angioplasty procedure became a promising minimally invasive therapy based on re-opening narrowed arteries by stent insertion. In order to improve and optimize this method, many research groups are focusing on designing new or improving existent stents. Since the beginning of the stent development in 1986, starting with bare-metal stents (BMS), these devices have been continuously enhanced by applying new materials, developing stent coatings based on inorganic and organic compounds including drugs, nanoparticles or biological components such as genes and cells, as well as adapting stent designs with different fabrication technologies. Drug eluting stents (DES) have been developed to overcome the main shortcomings of BMS or coated stents. Coatings are mainly applied to control biocompatibility, degradation rate, protein adsorption, and allow adequate endothelialization in order to ensure better clinical outcome of BMS, reducing restenosis and thrombosis. As coating materials (i) organic polymers: polyurethanes, poly(ε-caprolactone), styrene-b-isobutylene-b-styrene, polyhydroxybutyrates, poly(lactide-co-glycolide), and phosphoryl choline; (ii) biological components: vascular endothelial growth factor (VEGF) and anti-CD34 antibody and (iii) inorganic coatings: noble metals, wide class of oxides, nitrides, silicide and carbide, hydroxyapatite, diamond-like carbon, and others are used. DES were developed to reduce the tissue hyperplasia and in-stent restenosis utilizing antiproliferative substances like paclitaxel, limus (siro-, zotaro-, evero-, bio-, amphi-, tacro-limus), ABT-578, tyrphostin AGL-2043, genes, etc. The innovative solutions aim at overcoming the main limitations of the stent technology, such as in-stent restenosis and stent thrombosis, while maintaining the prime requirements on biocompatibility, biodegradability, and mechanical behavior. This paper provides an overview of the existing stent types, their functionality, materials, and manufacturing conditions demonstrating the still huge potential for the development of promising stent solutions.
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Affiliation(s)
- Natalia Beshchasna
- Fraunhofer Institute for Ceramic Technologies and Systems IKTS, Maria-Reiche-Str. 2, 01109 Dresden, Germany; (M.S.); (J.O.)
| | - Muhammad Saqib
- Fraunhofer Institute for Ceramic Technologies and Systems IKTS, Maria-Reiche-Str. 2, 01109 Dresden, Germany; (M.S.); (J.O.)
| | | | - Łukasz Wasyluk
- Balton Sp. z o.o. Modlińska 294, 03-152 Warsaw, Poland; (H.K.); (Ł.W.)
| | - Oleg Kuzmin
- VIP Technologies, Prospect Academicheskiy 8/2, 634055 Tomsk, Russia;
| | - Oana Cristina Duta
- Department of Science and Engineering of Oxide Materials, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, Spl. Independentei 313, 060042 Bucharest, Romania; (O.C.D.); (D.F.); (Z.G.); (E.A.)
| | - Denisa Ficai
- Department of Science and Engineering of Oxide Materials, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, Spl. Independentei 313, 060042 Bucharest, Romania; (O.C.D.); (D.F.); (Z.G.); (E.A.)
| | - Zeno Ghizdavet
- Department of Science and Engineering of Oxide Materials, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, Spl. Independentei 313, 060042 Bucharest, Romania; (O.C.D.); (D.F.); (Z.G.); (E.A.)
| | - Alexandru Marin
- Department of Hydraulics, Hydraulic Machinery and Environmental Engineering, Faculty of Power Engineering, University Politehnica of Bucharest, Spl. Independentei 313, 060042 Bucharest, Romania;
| | - Anton Ficai
- Department of Science and Engineering of Oxide Materials, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, Spl. Independentei 313, 060042 Bucharest, Romania; (O.C.D.); (D.F.); (Z.G.); (E.A.)
- Academy of Romanian Scientists, Spl. Independentei 54, 050094 Bucharest, Romania
| | - Zhilei Sun
- Research School of High-Energy Physics, Tomsk Polytechnic University, Lenin Avenue 30, 634050 Tomsk, Russia;
| | - Vladimir F. Pichugin
- Research School of High-Energy Physics, Tomsk Polytechnic University, Lenin Avenue 30, 634050 Tomsk, Russia;
| | - Joerg Opitz
- Fraunhofer Institute for Ceramic Technologies and Systems IKTS, Maria-Reiche-Str. 2, 01109 Dresden, Germany; (M.S.); (J.O.)
| | - Ecaterina Andronescu
- Department of Science and Engineering of Oxide Materials, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, Spl. Independentei 313, 060042 Bucharest, Romania; (O.C.D.); (D.F.); (Z.G.); (E.A.)
- Academy of Romanian Scientists, Spl. Independentei 54, 050094 Bucharest, Romania
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Fu J, Su Y, Qin YX, Zheng Y, Wang Y, Zhu D. Evolution of metallic cardiovascular stent materials: A comparative study among stainless steel, magnesium and zinc. Biomaterials 2020; 230:119641. [PMID: 31806406 PMCID: PMC6934082 DOI: 10.1016/j.biomaterials.2019.119641] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 11/16/2019] [Accepted: 11/19/2019] [Indexed: 12/22/2022]
Abstract
A cardiovascular stent is a small mesh tube that expands a narrowed or blocked coronary artery. Unfortunately, current stents, regardless metallic or polymeric, still largely fall short to the ideal clinical needs due to late restenosis, thrombosis and other clinical complications. Nonetheless, metallic stents are preferred clinically thanks to their superior mechanical property and radiopacity to their polymeric counterparts. The emergence of bioresorbable metals opens a window for better stent materials as they may have the potential to reduce or eliminate late restenosis and thrombosis. In fact, some bioresorbable magnesium (Mg)-based stents have obtained regulatory approval or under trials with mixed clinical outcomes. Some major issues with Mg include the too rapid degradation rate and late restenosis. To mitigate these problems, bioresorbable zinc (Zn)-based stent materials are being developed lately with the more suitable degradation rate and better biocompatibility. The past decades have witnessed the unprecedented evolution of metallic stent materials from first generation represented by stainless steel (SS), to second generation represented by Mg, and to third generation represented by Zn. To further elucidate their pros and cons as metallic stent materials, we systematically evaluated their performances in vitro and in vivo through direct side-by-side comparisons. Our results demonstrated that tailored Zn-based material with proper configurations could be a promising candidate for a better stent material in the future.
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Affiliation(s)
- Jiayin Fu
- Nancy E. and Peter C. Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, USA
| | - Yingchao Su
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, USA
| | - Yi-Xian Qin
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, USA
| | - Yufeng Zheng
- Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing, China
| | - Yadong Wang
- Nancy E. and Peter C. Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, USA.
| | - Donghui Zhu
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, USA.
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Mohtashami Z, Esmaili Z, Vakilinezhad MA, Seyedjafari E, Akbari Javar H. Pharmaceutical implants: classification, limitations and therapeutic applications. Pharm Dev Technol 2019; 25:116-132. [DOI: 10.1080/10837450.2019.1682607] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Zahra Mohtashami
- Pharmaceutics Department, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Zahra Esmaili
- Pharmaceutics Department, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | | | | | - Hamid Akbari Javar
- Pharmaceutics Department, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
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Loffredo S, Paternoster C, Giguère N, Barucca G, Vedani M, Mantovani D. The addition of silver affects the deformation mechanism of a twinning-induced plasticity steel: Potential for thinner degradable stents. Acta Biomater 2019; 98:103-113. [PMID: 31004841 DOI: 10.1016/j.actbio.2019.04.030] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 03/11/2019] [Accepted: 04/11/2019] [Indexed: 01/24/2023]
Abstract
While Fe-based alloys have already been reported to possess all mechanical properties required for vascular stenting, their relatively low degradation rate in vivo still constitutes their main bottleneck. The inflammatory reaction generated by a stent is inversely proportional to its mass. Therefore, the tendency in stenting is to lower the section so to reduce the inflammatory reaction. Twinning-induced plasticity steels (TWIP) possess excellent mechanical properties for envisaging the next generation of thinner degradable cardiovascular stents. To accelerate the degradation, the addition of noble elements was proposed, aimed at promoting corrosion by galvanic coupling. In this context, silver was reported to generally increase the degradation rate. However, its impact on the deformation mechanism of TWIP steels has not been reported yet. Results show that the use of Ag significantly reduces the ductility without altering the strength of the material. Furthermore, the presence of Ag was found to promote a different deformation texture, thus stimulating the formation of mechanical martensite. Since a stent works in the deformed state, understanding the microstructure and texture resulting from plastic deformation can effectively help to forecast the degradation mechanisms taking place during implantation and the expected degradation time. Moreover, knowing the deformed microstructure allows to understand the formability of very small tubes, as precursors of the next generation of thin section degradable stents. STATEMENT OF SIGNIFICANCE: Commercial degradable magnesium stents are limited from their relatively big structure size. Twinning-induced plasticity steels possess outstanding mechanical properties, but their degradation time goes beyond the timeframe expected from clinics. The inclusion of noble Ag particles, which favor galvanic coupling, is known to promote corrosion and solve this limitation. However, it is necessary to understand the impact that Ag has on the deformation microstructure and on the mechanical properties. The addition of Ag reduces the ductility of a twinning-induced plasticity steel because of a different deformation microstructure. Since a stent works in a deformed state inside an artery, understanding the microstructural evolution after plastic deformation allows to better predict the device performances during service life.
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32
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Boland EL, Grogan JA, McHugh PE. Computational modelling of magnesium stent mechanical performance in a remodelling artery: Effects of multiple remodelling stimuli. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2019; 35:e3247. [PMID: 31393090 DOI: 10.1002/cnm.3247] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 05/01/2019] [Accepted: 08/03/2019] [Indexed: 06/10/2023]
Abstract
Significant research has been conducted in the area of coronary stents/scaffolds made from resorbable metallic and polymeric biomaterials. These next-generation bioabsorbable stents have the potential to completely revolutionise the treatment of coronary artery disease. The primary advantage of resorbable devices over permanent stents is their temporary presence which, from a theoretical point of view, means only a healed coronary artery will be left behind following degradation of the stent potentially eliminating long-term clinical problems associated with permanent stents. The healing of the artery following coronary stent/scaffold implantation is crucial for the long-term safety of these devices. Computational modelling can be used to evaluate the performance of complex stent devices in silico and assist in the design and development and understanding of the next-generation resorbable stents. What is lacking in computational modelling literature is the representation of the active response of the arterial tissue in the weeks and months following stent implantation, ie, neointimal remodelling, in particular for the case of biodegradable stents. In this paper, a computational modelling framework is developed, which accounts for two major physiological stimuli responsible for neointimal remodelling and combined with a magnesium corrosion model that is capable of simulating localised pitting (realistic) stent corrosion. The framework is used to simulate different neointimal growth patterns and to explore the effects the neointimal remodelling has on the mechanical performance (scaffolding support) of the bioabsorbable magnesium stent.
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Affiliation(s)
- Enda L Boland
- Biomechanics Research Centre (BioMEC), Biomedical Engineering, College of Engineering and Informatics, National University of Ireland Galway, Galway, Ireland
| | - James A Grogan
- Biomechanics Research Centre (BioMEC), Biomedical Engineering, College of Engineering and Informatics, National University of Ireland Galway, Galway, Ireland
| | - Peter E McHugh
- Biomechanics Research Centre (BioMEC), Biomedical Engineering, College of Engineering and Informatics, National University of Ireland Galway, Galway, Ireland
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Early-Stage Vascular Response between Bare Metal Stent and Drug-Free Bioresorbable Vascular Scaffold in the Small-Sized Peripheral Artery: A Preclinical Study in Porcine Femoral Arteries. Ann Vasc Surg 2019; 60:388-396. [PMID: 31200063 DOI: 10.1016/j.avsg.2019.03.034] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2019] [Revised: 03/11/2019] [Accepted: 03/14/2019] [Indexed: 11/24/2022]
Abstract
BACKGROUND The clinical benefits and outcomes of the interventional treatment of small-sized infrapopliteal arteries using stent implantation remain uncertain. The aim of this study was to compare the safety and efficacy of drug-free bioresorbable vascular scaffold (BVS) with that of bare metal stent (BMS) in endovascular treatment of small-sized peripheral arteries. METHODS In this study, drug-free BVS and BMS were used in eight porcine models. We compared the angiographic and histomorphometric findings in the two groups at 4 weeks. In each pig, BVS and BMS of adequate sizes were implanted in the small branch (<3 mm) of the femoral artery. Angiography, intravascular ultrasound (IVUS), and histomorphometric analysis were performed at 4 weeks. RESULTS In the 4-week follow-up angiography and IVUS examination, the minimal luminal diameter was smaller and diameter stenosis was more severe in the BVS group. Histomorphometric findings indicated that the lumen area in the BVS group was smaller (0.34 ± 0.28 mm2 vs. 1.40 ± 0.52 mm2, P < 0.001), whereas the neointimal area (2.70 ± 1.28 mm2 vs. 1.76 ± 0.66 mm2, P = 0.013), area stenosis (85.18 ± 13.14 % vs. 54.99 ± 16.13 %, P < 0.001), inflammatory score (2.07 ± 0.861 vs. 28 ± 0.39, P = 0.003), and fibrin scores (1.24 ± 0.70 vs. 0.79 ± 0.72, P = 0.043) were significantly higher in the BVS group. The injury score was higher in the BMS group. In histopathologic findings, restenosis was mainly due to recoil and distortion of the scaffold in the BVS group. CONCLUSIONS Compared with BMS, drug-free BVS was not feasible for small-sized peripheral arteries based on the angiographic, IVUS, and histomorphometric results primarily due to insufficient mechanical support.
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Fabrication and Characterization of Bioresorbable Drug-coated Porous Scaffolds for Vascular Tissue Engineering. MATERIALS 2019; 12:ma12091438. [PMID: 31052587 PMCID: PMC6539797 DOI: 10.3390/ma12091438] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 04/24/2019] [Accepted: 04/28/2019] [Indexed: 02/03/2023]
Abstract
Bioresorbable polymers have been studied for several decades as attractive candidates for promoting the advancement of medical science and bio-technology in modern society. In particular, with a well-defined architecture, bioresorbable polymers have prominent advantages over their bulk counterparts for applications in biomedical and implant devices, such as cell delivery, scaffolds for tissue engineering, and hydrogels as well as in the pharmaceutical fields. Biocompatible implant devices based on bioresorbable materials (for instance, bioresorbable polymers that combine the unique advantages of biocompability and easy handling) have emerged as a highly active field due to their promising applications in artificial implant systems and biomedical devices. In this paper, we report an approach to fabricate porous polycaprolactone (PCL) scaffolds using a 3D printing system. And its surface was treated to a hydrophilic surface using plasma treatment. Then, the aspirin and atorvastatin calcium salt mixture was dip coated onto the surface. The drug coating technology was used to deposit the drug material onto the scaffold surface. Our porous PCL scaffold was coated with aspirin and atorvastatin calcium salt to reduce the blood LDL cholesterol and restenosis. These results suggest that our approach may provide a promising scaffold for developing bioresorbable drug-delivery-biomaterials. We further demonstrate that our bioresorbable medical device can be used as vascular scaffolds to provide a wide range of applications for the design of medical devices.
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Peng K, Cui X, Qiao A, Mu Y. Mechanical analysis of a novel biodegradable zinc alloy stent based on a degradation model. Biomed Eng Online 2019; 18:39. [PMID: 30940146 PMCID: PMC6444843 DOI: 10.1186/s12938-019-0661-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 03/26/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Biodegradable stents display insufficient scaffold performance due to their poor Young's Modulus. In addition, the corresponding biodegradable materials harbor weakened structures during degradation processes. Consequently, such stents have not been extensively applied in clinical therapy. In this study, the scaffold performance of a patented stent and its ability to reshape damaged vessels during degradation process were evaluated. METHODS A common stent was chosen as a control to assess the mechanical behavior of the patented stent. Finite element analysis was used to simulate stent deployment into a 40% stenotic vessel. A material corrosion model involving uniform and stress corrosion was implemented within the finite element framework to update the stress state following degradation. RESULTS The results showed that radial recoiling ratio and mass loss ratio of the patented stent is 7.19% and 3.1%, respectively, which are definitely lower than those of the common stent with the corresponding values of 22.6% and 14.1%, respectively. Moreover, the patented stent displayed stronger scaffold performance in a corrosive environment and the plaque treated with patented stents had a larger and flatter lumen. CONCLUSION Owing to its improved mechanical performance, the novel biodegradable zinc alloy stent reported here has high potential as an alternative choice in surgery.
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Affiliation(s)
- Kun Peng
- College of Life Science and Bioengineering, Beijing University of Technology, No.100, Pingleyuan, Chaoyang District, Beijing, 100124 China
| | - Xinyang Cui
- College of Life Science and Bioengineering, Beijing University of Technology, No.100, Pingleyuan, Chaoyang District, Beijing, 100124 China
| | - Aike Qiao
- College of Life Science and Bioengineering, Beijing University of Technology, No.100, Pingleyuan, Chaoyang District, Beijing, 100124 China
| | - Yongliang Mu
- Northeastern University, Shenyang, 110819 Liaoning China
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De Palo M, Quagliara T, Dachille A, Carrozzo A, Giardinelli F, Mureddu S, Mastro F, Rotunno C, Paparella D. Trials Comparing Percutaneous And Surgical Myocardial Revascularization: A Review. Rev Recent Clin Trials 2019; 14:95-105. [PMID: 30706789 DOI: 10.2174/1574887114666190201102353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 06/10/2018] [Accepted: 12/05/2018] [Indexed: 11/22/2022]
Abstract
INTRODUCTION Ischemic heart diseases are the major leading cause of death worldwide. Revascularization procedures dramatically reduced the overall risk for death related to acute coronary syndromes. Two kinds of myocardial revascularization can grossly be outlined: percutaneous coronary intervention (PCI) and surgical coronary artery bypass graft intervention (CABG). The net clinical benefit coming from these two kinds of procedures is still under debate. METHODS We have traced the state-of-the-art background about myocardial revascularization procedures by comparing the most important trials dealing with the evaluation of percutaneous interventions versus a surgical approach to coronary artery diseases. RESULTS Both PCI and CABG have become effective treatments for revascularization of patients suffering from advanced CAD. The advance in technology and procedural techniques made PCI an attractive and, to some extent, more reliable procedure in the context of CAD. However, there are still patients that cannot undergo PCI and have to be rather directed towards CABG. CONCLUSION CABG still remains the best strategy for the treatment of multiple vessel CAD due to improved results in term of survival and freedom from reintervention. Anyway, a systematic, multidisciplinary approach to revascularization is the fundamental behaviour to be chased in order to effectively help the patients in overcoming its diseases. The creation of the "heart team" seems to be a good option for the correct treatment of patients suffering from stable and unstable CAD.
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Affiliation(s)
- Micaela De Palo
- Department of Emergency and Organ Transplant, Division of Cardiac Surgery, University of Bari Aldo Moro, Bari, Italy.,Department of Cardiovascular Diseases, Mater Dei Hospital, Bari, Italy
| | - Teresa Quagliara
- Department of Emergency and Organ Transplant, Division of Cardiac Surgery, University of Bari Aldo Moro, Bari, Italy
| | - Annamaria Dachille
- Department of Emergency and Organ Transplant, Division of Cardiac Surgery, University of Bari Aldo Moro, Bari, Italy
| | - Alessandro Carrozzo
- Department of Emergency and Organ Transplant, Division of Cardiac Surgery, University of Bari Aldo Moro, Bari, Italy
| | - Francesco Giardinelli
- Department of Emergency and Organ Transplant, Division of Cardiac Surgery, University of Bari Aldo Moro, Bari, Italy
| | - Simone Mureddu
- Department of Emergency and Organ Transplant, Division of Cardiac Surgery, University of Bari Aldo Moro, Bari, Italy
| | - Florinda Mastro
- Department of Emergency and Organ Transplant, Division of Cardiac Surgery, University of Bari Aldo Moro, Bari, Italy
| | | | - Domenico Paparella
- Department of Emergency and Organ Transplant, Division of Cardiac Surgery, University of Bari Aldo Moro, Bari, Italy.,Department of Cardiovascular Surgery, GVM Care and Research, Santa Maria Hospital, Bari, Italy
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Nagaraja V, Moss S, Jepson NS, Pitney MR. Saphenous vein graft intervention with a bioresorbable vascular scaffold: a follow-up optical coherence tomography study at 40 months. ASIAINTERVENTION 2019; 5:27-31. [PMID: 36483936 PMCID: PMC9706773 DOI: 10.4244/aij-d-18-00020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 11/19/2018] [Indexed: 06/17/2023]
Affiliation(s)
- Vinayak Nagaraja
- Department of Cardiology, Prince of Wales Hospital, Sydney, Australia
| | | | - Nigel S Jepson
- Department of Cardiology, Prince of Wales Hospital, Sydney, Australia
| | - Mark R Pitney
- Sutherland Heart Clinic, Sutherland Hospital, Sydney, Australia
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Pradhan A, Vishwakarma P, Vankar S, Sethi R. "The Unpredictable ABSORB" - Very Late Stent Thrombosis of Bioresorbable Vascular Scaffold. Heart Views 2019; 20:65-69. [PMID: 31462962 PMCID: PMC6686611 DOI: 10.4103/heartviews.heartviews_18_19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Bioresorbable vascular scaffolds represent the next revolution in stent technology. They serve the dual purpose of antiproliferative drug delivery to vascular lumen like a drug-eluting stents (DES) as well as phased strut resorption over time leading to virtual elimination of stent thrombosis. The ABSORB GT-1 stent was the prototype bioresrbable vascular scaffold with maximum clinical experience and initial promising results. However, reports of stent thrombosis emerged with ABSORB too. Although the use of intracoronary imaging and proper implantation technique has the potential to reduce stent thrombosis rates, the device has been withdrawn from the market for now. We report a case of late stent thrombosis with ABSORB which was managed with DES-supported intracoronary imaging.
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Affiliation(s)
- Akshyaya Pradhan
- Department of Cardiology, King George's Medical University, Lucknow, Uttar Pradesh, India
| | - Pravesh Vishwakarma
- Department of Cardiology, King George's Medical University, Lucknow, Uttar Pradesh, India
| | - Sameer Vankar
- Department of Cardiology, King George's Medical University, Lucknow, Uttar Pradesh, India
| | - Rishi Sethi
- Department of Cardiology, King George's Medical University, Lucknow, Uttar Pradesh, India
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Lin S, Ran X, Yan X, Yan W, Wang Q, Yin T, Zhou JG, Hu T, Wang G. Corrosion behavior and biocompatibility evaluation of a novel zinc-based alloy stent in rabbit carotid artery model. J Biomed Mater Res B Appl Biomater 2018; 107:1814-1823. [PMID: 30408310 DOI: 10.1002/jbm.b.34274] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 08/21/2018] [Accepted: 10/07/2018] [Indexed: 02/06/2023]
Abstract
Zinc (Zn) and its alloys have been proved to be promising candidate materials for biodegradable cardiovascular stents. In this study, a novel extruded Zn-0.02 Mg-0.02Cu alloy was prepared. Compared with pure Zn, the Zn-based alloy showed higher mechanical properties, and the Zn-based alloy could significantly accelerate Zn2+ release, reaching 0.61 ± 0.11 μg/mL at 15 days of immersion. In vitro biocompatibility studies demonstrated that the Zn-based alloy had excellent cytocompatibility and hemocompatibility, including low hemolysis rate (0.63 ± 0.12%) and strong inhibitory effect on platelet adhesion. Subsequently, the Zn-based alloy stent was implanted into the left carotid arteries of New Zealand white rabbits for 12 months. All the rabbits survived without any adverse clinical events, and all the stented arteries were patent during the study period. Rapid endothelialization at 1 week of implantation was observed, suggesting a low cytotoxicity and thrombosis risk. The stent corroded slowly and no obvious intimal hyperplasia was observed for 6 months, after which corrosion accelerated at 12 months. In addition, no obvious thrombosis and systemic toxicity during implantation period were observed, indicating its potential as the backbone of biodegradable cardiovascular stents. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1814-1823, 2019.
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Affiliation(s)
- Song Lin
- Key Laboratory for Biorheological Science and Technology of Ministry of Education, State and Local Joint Engineering Laboratory for Vascular Implants, Bioengineering College of Chongqing University, Chongqing, 400030, China
| | - Xiaolin Ran
- Key Laboratory for Biorheological Science and Technology of Ministry of Education, State and Local Joint Engineering Laboratory for Vascular Implants, Bioengineering College of Chongqing University, Chongqing, 400030, China
| | - Xinhao Yan
- Xi'an Advanced Medical Technology Co., Ltd, Xi'an, 710000, China
| | - Wenhua Yan
- Key Laboratory for Biorheological Science and Technology of Ministry of Education, State and Local Joint Engineering Laboratory for Vascular Implants, Bioengineering College of Chongqing University, Chongqing, 400030, China
| | - Qilong Wang
- Key Laboratory for Biorheological Science and Technology of Ministry of Education, State and Local Joint Engineering Laboratory for Vascular Implants, Bioengineering College of Chongqing University, Chongqing, 400030, China
| | - Tieying Yin
- Key Laboratory for Biorheological Science and Technology of Ministry of Education, State and Local Joint Engineering Laboratory for Vascular Implants, Bioengineering College of Chongqing University, Chongqing, 400030, China
| | - Jack G Zhou
- Xi'an Advanced Medical Technology Co., Ltd, Xi'an, 710000, China
| | - Tingzhang Hu
- Key Laboratory for Biorheological Science and Technology of Ministry of Education, State and Local Joint Engineering Laboratory for Vascular Implants, Bioengineering College of Chongqing University, Chongqing, 400030, China
| | - Guixue Wang
- Key Laboratory for Biorheological Science and Technology of Ministry of Education, State and Local Joint Engineering Laboratory for Vascular Implants, Bioengineering College of Chongqing University, Chongqing, 400030, China
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Borhani S, Hassanajili S, Ahmadi Tafti SH, Rabbani S. Cardiovascular stents: overview, evolution, and next generation. Prog Biomater 2018; 7:175-205. [PMID: 30203125 PMCID: PMC6173682 DOI: 10.1007/s40204-018-0097-y] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 08/25/2018] [Indexed: 12/01/2022] Open
Abstract
Compared to bare-metal stents (BMSs), drug-eluting stents (DESs) have been regarded as a revolutionary change in coronary artery diseases (CADs). Releasing pharmaceutical agents from the stent surface was a promising progress in the realm of cardiovascular stents. Despite supreme advantages over BMSs, in-stent restenosis (ISR) and long-term safety of DESs are still deemed ongoing concerns over clinically application of DESs. The failure of DESs for long-term clinical use is associated with following factors including permanent polymeric coating materials, metallic stent platforms, non-optimal drug releasing condition, and factors that have recently been supposed as contributory factors such as degradation products of polymers, metal ions due to erosion and degradation of metals and their alloys utilizing in some stents as metal frameworks. Discovering the direct relation between stent materials and associating adverse effects is a complicated process, and yet it has not been resolved. For clinical success it is of significant importance to optimize DES design and explore novel strategies to overcome all problems including inflammatory response, delay endothelialization, and sub-acute stent thrombosis (ST) simultaneously. In this work, scientific reports are reviewed particularly focusing on recent advancements in DES design which covers both potential improvements of existing and recently novel prototype stent fabrications. Covering a wide range of information from the BMSs to recent advancement, this study mostly sheds light on DES's concepts, namely stent composition, drug release mechanism, and coating techniques. This review further reports different forms of DES including fully biodegradable DESs, shape-memory ones, and polymer-free DESs.
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Affiliation(s)
- Setareh Borhani
- Department of Chemical Engineering, School of Chemical and Petroleum Engineering, Shiraz University, Shiraz, Iran
| | - Shadi Hassanajili
- Department of Nanochemical Engineering, School of New Science and Technology, Shiraz University, Shiraz, Iran.
| | - Seyed Hossein Ahmadi Tafti
- Research Center for Advanced Technologies in Cardiovascular Medicine, Tehran Heart Center, Tehran University of Medical Sciences, North Kargar, Tehran, Iran
| | - Shahram Rabbani
- Research Center for Advanced Technologies in Cardiovascular Medicine, Tehran Heart Center, Tehran University of Medical Sciences, North Kargar, Tehran, Iran
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Ungar L, Sanders D, Becerra B, Barseghian A. Percutaneous Coronary Intervention in Familial Hypercholesterolemia Is Understudied. Front Cardiovasc Med 2018; 5:116. [PMID: 30214904 PMCID: PMC6125301 DOI: 10.3389/fcvm.2018.00116] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 08/08/2018] [Indexed: 01/09/2023] Open
Abstract
Familial hypercholesterolemia (FH) is a common heritable condition in which mutations of genes governing cholesterol metabolism result in elevated LDL levels and accelerated atherosclerosis. The treatment of FH focuses on lipid lowering drugs to decrease patients' cholesterol levels and reduce their risk of cardiovascular events. Even with optimal medical therapy, some FH patients will develop coronary atherosclerosis, suffer myocardial infarction, and require revascularization. Yet, the revascularization of FH patients has not been widely studied. Here we review FH, identify unanswered questions in the interventional management of FH patients, and explore barriers and opportunities for answering these questions. Further research is needed in this neglected but important topic in interventional cardiology.
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Affiliation(s)
- Leo Ungar
- Department of Cardiology, University of California, Irvine, Irvine, CA, United States
| | - David Sanders
- Department of Internal Medicine, University of California, Irvine, Irvine, CA, United States
| | - Brian Becerra
- Department of Internal Medicine, University of California, Irvine, Irvine, CA, United States
| | - Ailin Barseghian
- Department of Cardiology, University of California, Irvine, Irvine, CA, United States
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43
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Jia H, Gu SY, Chang K. 3D printed self-expandable vascular stents from biodegradable shape memory polymer. ADVANCES IN POLYMER TECHNOLOGY 2018. [DOI: 10.1002/adv.22091] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Han Jia
- Department of Polymeric Materials; School of Materials Science and Engineering; Tongji University; Shanghai China
| | - Shu-Ying Gu
- Department of Polymeric Materials; School of Materials Science and Engineering; Tongji University; Shanghai China
- Key Laboratory of Advanced Civil Engineering Materials; Ministry of Education; Tongji University; Shanghai China
| | - Kun Chang
- Department of Polymeric Materials; School of Materials Science and Engineering; Tongji University; Shanghai China
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Chen Y, Murphy A, Scholz D, Geever LM, Lyons JG, Devine DM. Surface-modified halloysite nanotubes reinforced poly(lactic acid) for use in biodegradable coronary stents. J Appl Polym Sci 2018. [DOI: 10.1002/app.46521] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Yuanyuan Chen
- Materials Research Institute, Athlone Institute of Technology; Athlone Ireland
| | - Alan Murphy
- Materials Research Institute, Athlone Institute of Technology; Athlone Ireland
| | - Dimitri Scholz
- Conway Institute, University College Dublin; Dublin Ireland
| | - Luke M. Geever
- Materials Research Institute, Athlone Institute of Technology; Athlone Ireland
| | - John G. Lyons
- Materials Research Institute, Athlone Institute of Technology; Athlone Ireland
- Faculty of Engineering & Informatics, Applied Polymer Technology; Athlone Institute of Technology; Athlone Ireland
| | - Declan M. Devine
- Materials Research Institute, Athlone Institute of Technology; Athlone Ireland
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Abstract
INTRODUCTION Percutaneous coronary intervention (PCI) is 40 years old this year. From its humble beginnings of experimental work, PCI has transitioned over years with coronary artery stenting now a standard medical procedure performed throughout the world. Areas covered: The conversion from plain old balloon angioplasty (POBA) to the present era of drug eluting stents (DES) has been driven by many technological advances and large bodies of clinical trial evidence. The journey to present day practice has seen many setbacks, such as acute vessel closure with POBA; rates of instant restenosis with bare metal stents (BMS) and more recently, high rates of stent thrombosis with bioabsorbable platforms. This work discusses POBA, why there was a need for BMS, the use of inhibiting drugs to create 1st generation DES, the change of components to 2nd generation DES, the use of absorbable drug reservoirs and platforms, and possible future directions with Prohealing Endothelial Progenitor Cell Capture Stents. Expert commentary: This paper reviews the evolution from the original pioneering work to modern day practice, highlighting landmark trials that changed practice. Modern day contemporary practice is now very safe based on the latest drug eluting stents and supported by large datasets.
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Affiliation(s)
| | | | - Naveed Ahmed
- a Cardiology , St Michael's Hospital Toronto , Toronto , Canada
| | - Michael Kutryk
- a Cardiology , St Michael's Hospital Toronto , Toronto , Canada
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Tipnis NP, Burgess DJ. Sterilization of implantable polymer-based medical devices: A review. Int J Pharm 2017; 544:455-460. [PMID: 29274370 DOI: 10.1016/j.ijpharm.2017.12.003] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 11/29/2017] [Accepted: 12/02/2017] [Indexed: 02/03/2023]
Abstract
This review article is focused on the sterilization techniques used for polymer-based implantable medical devices as well as the regulatory aspects governing sterile medical devices. Polymeric materials are increasingly used in implantable devices due to their biodegradable and biocompatible nature. Patients and medical staff often prefer long-term implantable devices and these can be achieved using high molecular weight polymers. Sterilization of polymer-based implantable devices is critical. Since all implantable devices must be sterile, the effect of the sterilization method on the different device components (such as, the polymer, the drug, the electronics, etc.) has to be considered. A comprehensive summary of the established sterilization methods is provided along with the possible effects on polymers. In addition, novel sterilization methods are also discussed.
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Affiliation(s)
- Namita P Tipnis
- University of Connecticut, Department of Pharmaceutical Sciences, Storrs, CT 06269, United States
| | - Diane J Burgess
- University of Connecticut, Department of Pharmaceutical Sciences, Storrs, CT 06269, United States.
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Testa L, Latib A, Montone RA, Colombo A, Bedogni F. Coronary Bioresorbable Vascular Scaffold Use in the Treatment of Coronary Artery Disease. Circ Cardiovasc Interv 2017; 9:CIRCINTERVENTIONS.116.003978. [PMID: 27412870 DOI: 10.1161/circinterventions.116.003978] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Accepted: 06/20/2016] [Indexed: 11/16/2022]
Abstract
Bioresorbable vascular scaffolds (BVS) represent a promising novel approach for the treatment of coronary artery disease. BVS promise to address some of the well-known limitations of current drug-eluting stents, while providing a transient scaffolding of the vessel to prevent acute vessel closure/recoil. Drug elution by BVS prevents neointimal proliferation in a similar fashion to drug-eluting stents, and complete bioresorption is associated with late vessel lumen enlargement, plaque regression, and restoration of vasomotion. Based on the pathophysiological reasons and on the results derived from clinical studies, BVS are increasingly being used in clinical practice. The aim of this review is to provide an overview of the current evidence supporting the use of BVS in clinical practice. In particular, we will discuss the randomized controlled trials and registries evaluating the clinical outcome of these devices, with a special focus on their application in patients with acute coronary syndrome and in specific lesion subsets (bifurcations, chronic total occlusions, and in-stent restenosis).
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Affiliation(s)
- Luca Testa
- From the Department of Cardiology, IRCCS Pol. S. Donato, S.Donato Milanese, Milan, Italy (L.T., R.A.M., F.B.); and Interventional Cardiology Unit, San Raffaele Scientific Institute and EMO-GVM Centro Cuore Columbus, Milan, Italy (A.L., A.C.).
| | - Azeem Latib
- From the Department of Cardiology, IRCCS Pol. S. Donato, S.Donato Milanese, Milan, Italy (L.T., R.A.M., F.B.); and Interventional Cardiology Unit, San Raffaele Scientific Institute and EMO-GVM Centro Cuore Columbus, Milan, Italy (A.L., A.C.)
| | - Rocco A Montone
- From the Department of Cardiology, IRCCS Pol. S. Donato, S.Donato Milanese, Milan, Italy (L.T., R.A.M., F.B.); and Interventional Cardiology Unit, San Raffaele Scientific Institute and EMO-GVM Centro Cuore Columbus, Milan, Italy (A.L., A.C.)
| | - Antonio Colombo
- From the Department of Cardiology, IRCCS Pol. S. Donato, S.Donato Milanese, Milan, Italy (L.T., R.A.M., F.B.); and Interventional Cardiology Unit, San Raffaele Scientific Institute and EMO-GVM Centro Cuore Columbus, Milan, Italy (A.L., A.C.)
| | - Francesco Bedogni
- From the Department of Cardiology, IRCCS Pol. S. Donato, S.Donato Milanese, Milan, Italy (L.T., R.A.M., F.B.); and Interventional Cardiology Unit, San Raffaele Scientific Institute and EMO-GVM Centro Cuore Columbus, Milan, Italy (A.L., A.C.)
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Washington KS, Bashur CA. Delivery of Antioxidant and Anti-inflammatory Agents for Tissue Engineered Vascular Grafts. Front Pharmacol 2017; 8:659. [PMID: 29033836 PMCID: PMC5627016 DOI: 10.3389/fphar.2017.00659] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 09/05/2017] [Indexed: 01/21/2023] Open
Abstract
The treatment of patients with severe coronary and peripheral artery disease represents a significant clinical need, especially for those patients that require a bypass graft and do not have viable veins for autologous grafting. Tissue engineering is being investigated to generate an alternative graft. While tissue engineering requires surgical intervention, the release of pharmacological agents is also an important part of many tissue engineering strategies. Delivery of these agents offers the potential to overcome the major concerns for graft patency and viability. These concerns are related to an extended inflammatory response and its impact on vascular cells such as endothelial cells. This review discusses the drugs that have been released from vascular tissue engineering scaffolds and some of the non-traditional ways that the drugs are presented to the cells. The impact of antioxidant compounds and gasotransmitters, such as nitric oxide and carbon monoxide, are discussed in detail. The application of tissue engineering and drug delivery principles to biodegradable stents is also briefly discussed. Overall, there are scaffold-based drug delivery techniques that have shown promise for vascular tissue engineering, but much of this work is in the early stages and there are still opportunities to incorporate additional drugs to modulate the inflammatory process.
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Affiliation(s)
| | - Chris A. Bashur
- Department of Biomedical Engineering, Florida Institute of Technology, MelbourneFL, United States
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Bagheri M, Mohammadi M, Steele TW, Ramezani M. Nanomaterial coatings applied on stent surfaces. Nanomedicine (Lond) 2017; 11:1309-26. [PMID: 27111467 DOI: 10.2217/nnm-2015-0007] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The advent of percutaneous coronary intervention and intravascular stents has revolutionized the field of interventional cardiology. Nonetheless, in-stent restenosis, inflammation and late-stent thrombosis are the major obstacles with currently available stents. In order to enhance the hemocompatibility of stents, advances in the field of nanotechnology allow novel designs of nanoparticles and biomaterials toward localized drug/gene carriers or stent scaffolds. The current review focuses on promising polymers used in the fabrication of newer generations of stents with a short synopsis on atherosclerosis and current commercialized stents, nanotechnology's impact on stent development and recent advancements in stent biomaterials is discussed in context.
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Affiliation(s)
- Mahsa Bagheri
- Shariati Hospital, Mashhad University of Medical Sciences, Mashhad, PO Box 935189-9983, Iran.,Nanotechnology Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, PO Box 91775-1365, Iran
| | - Marzieh Mohammadi
- Nanotechnology Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, PO Box 91775-1365, Iran
| | - Terry Wj Steele
- Division of Materials Technology, Materials & Science Engineering, Nanyang Technological University, Singapore
| | - Mohammad Ramezani
- Pharmaceutical Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, PO Box 91775-1365, Iran
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Drelich AJ, Zhao S, Guillory RJ, Drelich JW, Goldman J. Long-term surveillance of zinc implant in murine artery: Surprisingly steady biocorrosion rate. Acta Biomater 2017; 58:539-549. [PMID: 28532901 PMCID: PMC5553077 DOI: 10.1016/j.actbio.2017.05.045] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 05/03/2017] [Accepted: 05/18/2017] [Indexed: 10/19/2022]
Abstract
Metallic zinc implanted into the abdominal aorta of rats out to 6months has been demonstrated to degrade while avoiding responses commonly associated with the restenosis of vascular implants. However, major questions remain regarding whether a zinc implant would ultimately passivate through the production of stable corrosion products or via a cell mediated fibrous encapsulation process that prevents the diffusion of critical reactants and products at the metal surface. Here, we have conducted clinically relevant long term in vivo studies in order to characterize late stage zinc implant biocorrosion behavior and products to address these critical questions. We found that zinc wires implanted in the murine artery exhibit steady corrosion without local toxicity for up to at least 20months post-implantation, despite a steady buildup of passivating corrosion products and intense fibrous encapsulation of the wire. Although fibrous encapsulation was not able to prevent continued implant corrosion, it may be related to the reduced chronic inflammation observed between 10 and 20months post-implantation. X-ray elemental and infrared spectroscopy analyses confirmed zinc oxide, zinc carbonate, and zinc phosphate as the main components of corrosion products surrounding the Zn implant. These products coincide with stable phases concluded from Pourbaix diagrams of a physiological solution and in vitro electrochemical impedance tests. The results support earlier predictions that zinc stents could become successfully bio-integrated into the arterial environment and safely degrade within a time frame of approximately 1-2years. STAEMENT OF SIGNIFICANCE Previous studies have shown zinc to be a promising candidate material for bioresorbable endovascular stenting applications. An outstanding question, however, is whether a zinc implant would ultimately passivate through the production of stable corrosion products or via a cell mediated tissue encapsulation process that prevented the diffusion of critical reactants and products at the metal surface. We found that zinc wires implanted in the murine artery exhibit steady corrosion for up to at least 20months post-implantation. The results confirm earlier predictions that zinc stents could safely degrade within a time frame of approximately 1-2years.
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Affiliation(s)
- Adam J Drelich
- Department of Biomedical Engineering, Michigan Technological University, Houghton, MI 49931, USA
| | - Shan Zhao
- Department of Material Science and Engineering, Michigan Technological University, Houghton, MI 49931, USA
| | - Roger J Guillory
- Department of Biomedical Engineering, Michigan Technological University, Houghton, MI 49931, USA
| | - Jaroslaw W Drelich
- Department of Material Science and Engineering, Michigan Technological University, Houghton, MI 49931, USA
| | - Jeremy Goldman
- Department of Biomedical Engineering, Michigan Technological University, Houghton, MI 49931, USA.
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