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Background and Objective: Coronary artery disease remains a leading cause of mortality among individuals with cardiovascular conditions. The therapeutic use of bioresorbable vascular scaffolds (BVSs) through stent implantation is common, yet the effectiveness of current BVS segmentation techniques from Intravascular Optical Coherence Tomography (IVOCT) images is inadequate. Methods: This paper introduces an enhanced segmentation approach using a novel Wavelet-based U-shape network to address these challenges. We developed a Wavelet-based U-shape network that incorporates an Attention Gate (AG) and an Atrous Multi-scale Field Module (AMFM), designed to enhance the segmentation accuracy by improving the differentiation between the stent struts and the surrounding tissue. A unique wavelet fusion module mitigates the semantic gaps between different feature map branches, facilitating more effective feature integration. Results: Extensive experiments demonstrate that our model surpasses existing techniques in key metrics such as Dice coefficient, accuracy, sensitivity, and Intersection over Union (IoU), achieving scores of 85.10%, 99.77%, 86.93%, and 73.81%, respectively. The integration of AG, AMFM, and the fusion module played a crucial role in achieving these outcomes, indicating a significant enhancement in capturing detailed contextual information. Conclusion: The introduction of the Wavelet-based U-shape network marks a substantial improvement in the segmentation of BVSs in IVOCT images, suggesting potential benefits for clinical practices in coronary artery disease treatment. This approach may also be applicable to other intricate medical imaging segmentation tasks, indicating a broad scope for future research.

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Magnesium, iron, and zinc-based biodegradable metals are widely recognized as promising candidate materials for the next generation of bioresorbable stent (BVS). However, none of those metal BVSs are perfect at this stage. Here, a brand-new BVS based on a novel biodegradable metal (Molybdenum, Mo) through additive manufacturing is developed. Nearly full-dense and crack-free thin-wall Mo is directly manufactured through selective laser melting (SLM) with fine Mo powder. Systemic analyses considering the forming quality, wall-thickness, microstructure, mechanical properties, and in vitro degradation behaviors are performed. Then, Mo-based thin-strut (≤ 100 µm) stents are successfully obtained through an optimized single-track laser melting route. The SLMed thin-wall Mo owns comparable strength to its Mg and Zn based counterparts (as-drawn), while, it exhibits remarkable biocompatibility in vitro. Vessel related cells are well adhered and spread on SLMed Mo, and it exhibits a low risk of hemolysis and thrombus. The SLMed stent is compatible to vessel tissues in rat abdominal aorta, and it can provide sufficient support in an animal model as an extravascular stent. This work possibly opens a new era of manufacturing Mo-based stents through additive manufacturing.

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Background: Poly-L-lactic acid (PLLA) stents have broad application prospects in the treatment of cardiovascular diseases due to their excellent mechanical properties and biodegradability. However, foreign body reactions caused by stent implantation remain a bottleneck that limits the clinical application of PLLA stents. To solve this problem, the biocompatibility of PLLA stents must be urgently improved. Albumin, the most abundant inert protein in the blood, possesses the ability to modify the surface of biomaterials, mitigating foreign body reactions-a phenomenon described as the "stealth effect". In recent years, a strategy based on albumin camouflage has become a focal point in nanomedicine delivery and tissue engineering research. Therefore, albumin surface modification is anticipated to enhance the surface biological characteristics required for vascular stents. However, the therapeutic applicability of this modification has not been fully explored. Methods: Herein, a bionic albumin (PDA-BSA) coating was constructed on the surface of PLLA by a mussel-inspired surface modification technique using polydopamine (PDA) to enhance the immobilization of bovine serum albumin (BSA). Results: Surface characterization revealed that the PDA-BSA coating was successfully constructed on the surface of PLLA materials, significantly improving their hydrophilicity. Furthermore, in vivo and in vitro studies demonstrated that this PDA-BSA coating enhanced the anticoagulant properties and pro-endothelialization effects of the PLLA material surface while inhibiting the inflammatory response and neointimal hyperplasia at the implantation site. Conclusion: These findings suggest that the PDA-BSA coating provides a multifunctional biointerface for PLLA stent materials, markedly improving their biocompatibility. Further research into the diverse applications of this coating in vascular implants is warranted.

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The clinical performance of biodegradable polymer stents implanted in blood vessels is affected by uneven degradation. Stress distribution plays an important role in polymer degradation, and local stress concentration leads to the premature fracture of stents. Numerical simulations combined with in vitro experimental validation can accurately describe the degradation process and perform structural optimization. Compared with traditional design techniques, optimization based on surrogate models is more scientifically effective. Three stent structures were designed and optimized, with the effective working time during degradation as the optimization goal. The finite element method was employed to simulate the degradation process of the stent. Surrogate models were employed to establish the functional relationship between the design parameters and the degradation performance. The proposed function models accurately predicted the degradation performance of various stents. The optimized stent structures demonstrated improved degradation performance, with the kriging model showing a better optimization effect. This study provided a novel approach for optimizing the structural design of biodegradable polymer stents to enhance degradation performance.

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Biodegradable Zn alloys show great potential for vascular stents due to their moderate degradation rates and acceptable biocompatibility. However, the poor mechanical properties limit their applications. In this study, low alloyed Zn-2Cu-xLi (x = 0.004, 0.01, 0.07 wt %) alloys with favorable mechanical properties were developed. The microstructure consists of fine equiaxed η-Zn grains, micron, submicron-sized and coherent nano ε-CuZn4 phases. The introduced Li exists as a solute in the η-Zn matrix and ε-CuZn4 phase, and results in the increase of ε-CuZn4 volume fraction, the refinement of grains and more uniform distribution of grain sizes. As Li content increases, the strength of alloys is dramatically improved by grain boundary strengthening, precipitate strengthening of ε-CuZn4 and solid solution strengthening of Li. Zn-2Cu-0.07Li alloy has the optimal mechanical properties with a tensile yield strength of 321.8 MPa, ultimate tensile strength of 362.3 MPa and fracture elongation of 28.0 %, exceeding the benchmark of stents. It also has favorable mechanical property stability, weak tension compression yield asymmetry and strain rate sensitivity. It exhibits uniform degradation and a little improved degradation rate of 89.5 µm∙year-1, due to the improved electrochemical activity by increased ε-CuZn4 volume fraction, and generates Li2CO3 and LiOH. It shows favorable cytocompatibility without adverse influence on endothelial cell viability by trace Li+. The fabricated microtubes show favorable mechanical properties, and stents exhibit an average radial strength of 118 kPa. The present study indicates that Zn-2Cu-0.07Li alloy is a potential and promising candidate for vascular stent applications. STATEMENT OF SIGNIFICANCE: Zn alloys are promising candidates for biodegradable vascular stents. However, improving their mechanical properties is challenging. Combining the advantages of Cu and trace Li, Zn-2Cu-xLi (x < 0.1 wt %) alloys were developed for stents. As Li increases, the strength of alloys is dramatically improved by refined grains, increased volume fraction of ε-CuZn4 and solid solution of Li. Zn-2Cu-0.07Li alloy exhibits a TYS exceeding 320 MPa, UTS exceeding 360 MPa and fracture EL of nearly 30 %. It shows favorable mechanical stability, degradation behaviors and cytocompatibility. The alloy was fabricated into microtubes and stents for mechanical property tests to verify application feasibility for the first time. This indicates that Zn-2Cu-0.07Li alloy has great potential for vascular stent applications.

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BACKGROUND: Although the 1-year clinical outcomes of fluoropolymer-based drug-eluting stents (FP-DES) were favorable for the treatment of real-world femoropopliteal lesions in symptomatic peripheral artery disease (PAD), their performance beyond 1 year remained unknown. The current study determined the 3-year clinical course of FP-DES implantation for real-world femoropopliteal lesions. METHODS: This multicenter, prospective, observational study evaluated 1204 limbs (chronic limb-threatening ischemia, 34.8%; mean lesion length, 18.6 ± 9.9 cm, chronic total occlusion: 53.2%) of 1097 patients with PAD (age, 75 ± 9 years; diabetes mellitus, 60.8%) undergoing FP-DES implantation for femoropopliteal lesions. The primary outcome measure was 3-year restenosis. The secondary outcome measures included 3-year occlusive restenosis, stent thrombosis, target lesion revascularization (TLR), and aneurysmal degeneration. RESULTS: The 3-year cumulative occurrence of restenosis was 27.3%, whereas that of occlusive restenosis, stent thrombosis, and TLR was 16.1%, 7.3%, and 19.6%, respectively. The annual occurrence of restenosis decreased by 12.0%, 9.5%, and 5.8% in the first, second, and third year, respectively (p < 0.001). Similarly, the rates of occlusive restenosis and stent thrombosis decreased (p < 0.001 and p = 0.007, respectively), whereas the rate of TLR remained unchanged for 3 years (p = 0.15). The incidence of aneurysmal degeneration at 3 years (15.7%) did not significantly differ from that at 1 and 2 years (p = 0.69 and 0.20, respectively). CONCLUSIONS: This study highlights the favorable long-term clinical course of FP-DES in real-world practice, emphasizing the importance of monitoring for occlusive restenosis and stent thrombosis while considering the potential onset of aneurysmal degeneration.

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BACKGROUND: The popliteal artery is highly exposed to biomechanical stress, which is the primary factor associated with stent failure. However, information on the optimal endovascular treatment for the popliteal artery is lacking. OBJECTIVE: To report the efficacy of the GORE® TIGRIS® Vascular Stent for the endovascular treatment of popliteal artery lesions. METHODS: Retrospective analysis of all patients with symptoms of peripheral artery occlusive disease (PAD) and popliteal artery lesions who underwent implantation of a GORE® TIGRIS® Vascular Stent between August 2012 and August 2014 at a tertiary vascular centre. RESULTS: Between August 2012 and August 2014, 48 patients (32 men, aged 75±8 years) were treated with a GORE® TIGRIS® Vascular Stent. The technical success rate was 100%. At 12 months, the primary and secondary patency rates were 74% and 85%, respectively. During follow-up, no stent fracture was observed. No major amputations were performed. CONCLUSIONS: Our study showed that isolated popliteal artery lesions in patients with symptomatic PAD could easily be treated with the GORE® TIGRIS® Vascular Stent, as good short-term results were achieved at 12 months. Therefore, the discontinuation of this product removed a useful tool with a simple release mechanism from the endovascular armamentarium of vascular specialists.

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Endovascular stenting is a safer alternative to open surgery for use in treating cerebral arterial stenosis and significantly reduces the recurrence of ischemic stroke, but the widely used bare-metal stents (BMSs) often result in in-stent restenosis (ISR). Although evidence suggests that drug-eluting stents are superior to BMSs in the short term, their long-term performances remain unknown. Herein, we propose a potential vascular stent modified by immobilizing clickable chemerin 15 (C15) peptides on the stent surface to suppress coagulation and restenosis. Various characterization techniques and an animal model were used to evaluate the surface properties of the modified stents and their effects on endothelial injury, platelet adhesion, and inflammation. The C15-immobilized stent could prevent restenosis by minimizing endothelial injury, promoting physiological healing, restraining the platelet-leukocyte-related inflammatory response, and inhibiting vascular smooth muscle cell proliferation and migration. Furthermore, in vivo studies demonstrated that the C15-immobilized stent mitigated inflammation, suppressed neointimal hyperplasia, and accelerated endothelial restoration. The use of surface-modified, anti-inflammatory, endothelium-friendly stents may be of benefit to patients with arterial stenosis. STATEMENT OF SIGNIFICANCE: Endovascular stenting is increasingly used for cerebral arterial stenosis treatment, aiming to prevent and treat ischemic stroke. But an important accompanying complication is in-stent restenosis (ISR). Persistent inflammation has been established as a hallmark of ISR and anti-inflammation strategies in stent modification proved effective. Chemerin 15, an inflammatory resolution mediator with 15-aa peptide, was active at picomolar through cell surface receptor, no need to permeate cell membrane and involved in resolution of inflammation by inhibiting inflammatory cells adhesion, modulating macrophage polarization into protective phenotype, and reducing inflammatory factors release. The implications of this study are that C15 immobilized stent favors inflammation resolution and rapid re-endothelialization, and exhibits an inhibitory role of restenosis. As such, it helps the decreased incidence of ISR.

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Vascular stent implantation remains the major therapeutic method for cardiovascular diseases currently. We here introduced crucial biological functional biological function factors (SDF-1α, VEGF) and vital metal ions (Zn2+) into the stent surface to explore their synergistic effect in the microenvironment. The combination of the different factors is known to effectively regulate cellular inflammatory response and selectively regulate cell biological behavior. Meanwhile, in the implemented method, VEGF and Zn2+ were loaded into heparin and poly-l-lysine (Hep-PLL) nanoparticles, ensuring a controlled release of functional molecules with a multi-factor synergistic effect and excellent biological functions in vitro and in vivo. Notably, after 150 days of implantation of the modified stent in rabbits, a thin and smooth new intima was obtained. This study offers a new idea for constructing a modified surface microenvironment and promoting tissue repair.

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Over the last few decades, the use of covered stent grafts became increasingly popular; as it plays a pivotal role in the management of various atherosclerotic diseases that are rising in both incidence and prevalence. Subsequently, vascular stent infections, although rare, are becoming a well-recognized complication with possibly devastating consequences, owing to the difficulties associated with its diagnosis and treatment. This has prompted significant interest in the condition regarding its pathophysiology, modifiable and non-modifiable risk factors, diagnostic and therapeutic approaches, and the possible implementation of prophylactic measures. We herein present a case of a patient with an infected aortoiliac stent 4 weeks after endovascular revision with atherectomy and additional stent insertion. The patient initially developed nonspecific symptoms and later developed a life-threatening hemorrhage, which was urgently controlled using a percutaneously inserted covered stent at the infected site. Definitive treatment using extraanatomical bypass implantation and an explantation of the infected stents was performed with excellent clinical response.

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Magnesium alloy stents (MAS) have broad application prospects in the treatment of cardiovascular diseases. However, poor corrosion resistance and biocompatibility greatly limit the clinical application of MAS. In this work, the coating consisting of MgF2 layer, polydopamine layer, fucoidan and collagen IV was constructed on Mg-Zn-Y-Nd (ZE21B) alloy to improve its corrosion resistance and pro-endothelialization potential. The fucoidan and collagen IV in the coating could obviously enhance the hemocompatibility and pro-endothelialization potential respectively. Compared with bare ZE21B alloy, the fucoidan/collagen composite coating modified ZE21B alloy possessed lower corrosion current density and better corrosion resistance. Moreover, the modified ZE21B alloy exhibited relatively low hemolysis rate, fibrinogen adsorption and platelet adhesion in the blood experiments, suggesting the improved hemocompatibility. Furthermore, the modified ZE21B alloy favorably supported the adhesion and proliferation of vascular endothelial cells (ECs) and effectively regulated the phenotype of smooth muscle cells (SMCs), thus improving the pro-endothelialization potential of vascular stent materials. The fucoidan/collagen composite coating can significantly improve the corrosion resistance and pro-endothelialization potential of ZE21B alloy, showing great potential in the development of degradable MAS.

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BACKGROUND:Clinical use of vascular stents involves high medical costs,but it may also bring long-term benefits in reducing cardiovascular events and improving the quality of life in patients.Economics evaluation can help decision makers better understand the balance between the cost and benefit of treatment. OBJECTIVE:To analyze the related articles of health economics and discuss the hot spots in the study of the effect and problems of vascular stents in medical quality management. METHODS:The articles concerning health economics evaluation of vascular stents were retrieved from the core set of the Web of Science.The VOSviewer_1.6.19 software was used to make a visualization analysis of the annual publication volume,institutions,countries,keywords,etc.Finally,the research hot spots on the effects and problems of vascular stents were analyzed from the perspective of health economics and medical quality management. RESULTS AND CONCLUSION:(1)120 articles in English were finally included.In the past 10 years,the highest number of articles published in this field was in 2019,with 10 articles.The institution with the largest number of articles published was Harvard University in the United States with 20 articles,and the country with the largest number of articles published was the United States with 58 articles.(2)Keyword cluster analysis demonstrated that the cost-effectiveness analysis of bare metal stents and drug-eluting stents in coronary disease,the cost-effectiveness analysis of angioplasty stent intervention,and the effect of coronary stents in percutaneous coronary intervention are the research hot spots in the field of health economics evaluation of vascular stent research.(3)In the context of medical quality management,the paper further summarized the research hot spots on the therapeutic effect of vascular stents as follows:long-term effect of vascular stents,safety,drug release mechanism research,personalized therapy,restenosis problems,and stent insertion technology.(4)The results of highly cited literature analysis exhibited that drug-eluting stents release drugs to reduce the risk of vascular restenosis,and the restenosis rate is lower than that of bare metal stents,but the cost is usually higher.Biodegradable stents combine the advantages of bare metal stents and drug-eluting stents,that is,avoiding long-term stent existence and reducing the risk of restenosis,but their cost may be higher,and there may be some complications in the short term,and they are not widely used at present.(5)In addition to the direct stent cost,factors that need to be considered when comparing the cost-effectiveness of vascular stents include the risk and cost of stent re-intervention,the risk and cost of complications,the duration and cost of drug therapy,and the quality of life of patients.Therefore,while the initial cost of drug-eluting and biodegradable stents may be higher than bare metal stents,they may lead to better clinical outcomes in the long term,resulting in a more favorable cost effect.(6)Future research directions should focus on making personalized vascular stent treatment decisions,observing the long-term effect of stent treatment,the impact of the stent on patients'quality of life,formulating health policies,rational allocation of medical resources,and the establishment of long-term follow-up mechanisms.

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To evaluate the midterm efficacy of the Castor stent (CS) versus in situ fenestration (ISF) for reconstructing the left subclavian artery (LSA) in patients with type B aortic dissection (TBAD). Between July 2017 and July 2022, a total of 247 patients with TBAD were enrolled. One hundred thirty-seven patients were treated using CSs (group A), while the remaining 110 patients received ISFs (group B). Data of the two groups were retrospectively analyzed. The success rates of surgery were 99.3% and 95.5% in groups A and B (p = .053), There were no deaths during hospitalization. During surgery, group B showed a longer surgical duration [68.0 (66.0, 77.0) vs. 62.0 (59.0, 66.0) min, p < .001] and intraoperative fluoroscopy time [18.0 (16.0, 20.0) vs. 16.0 (14.0, 18.0) min, p < .001] than group A. The follow-up duration was similar for both groups (44.0 vs. 43.0 months, p = .877), and no patient died. Stent-related complications were significantly lower in group A than in group B (1.5% vs. 8.4%, p = .009). Group A had fewer instances entry flow (0.7% vs. 4.7%, p = .048) and stent stenosis (0.7% vs. 2.8%, p = .206) than group B. All reintervention cases (4.7%) were from group B (p = .011). The rate of false aortic lumen thrombosis was significantly higher in group A than in group B (84.6% vs. 72.9%, p = .024). Both CSs and ISFs are evidently safe, feasible, and effective in achieving positive early outcomes in patients undergoing treatment for TBAD. Notably, at midterm follow-up, CSs appeared to be superior to ISF in terms of reducing stent-related complications and minimizing the need for reintervention.

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Cardiovascular diseases are a pre-eminent global cause of mortality in the modern world. Typically, surgical intervention with implantable medical devices such as cardiovascular stents is deployed to reinstate unobstructed blood flow. Unfortunately, existing stent materials frequently induce restenosis and thrombosis, necessitating the development of superior biomaterials. These biomaterials should inhibit platelet adhesion (mitigating stent-induced thrombosis) and smooth muscle cell proliferation (minimizing restenosis) while enhancing endothelial cell proliferation at the same time. To optimize the surface properties of Ti6Al4V medical implants, we investigated two surface treatment procedures: gaseous plasma treatment and hydrothermal treatment. We analyzed these modified surfaces through scanning electron microscopy (SEM), water contact angle analysis (WCA), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) analysis. Additionally, we assessed in vitro biological responses, including platelet adhesion and activation, as well as endothelial and smooth muscle cell proliferation. Herein, we report the influence of pre/post oxygen plasma treatment on titanium oxide layer formation via a hydrothermal technique. Our results indicate that alterations in the titanium oxide layer and surface nanotopography significantly influence cell interactions. This work offers promising insights into designing multifunctional biomaterial surfaces that selectively promote specific cell types' proliferation─which is a crucial advancement in next-generation vascular implants.

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New horizons in cardiovascular research are opened by using 3D printing for biodegradable implants. This additive manufacturing approach allows the design and fabrication of complex structures according to the patient's imaging data in an accurate, reproducible, cost-effective, and quick manner. Acellular cardiovascular implants produced from biodegradable materials have the potential to provide enough support for in situ tissue regeneration while gradually being replaced by neo-autologous tissue. Subsequently, they have the potential to prevent long-term complications. In this Review, we discuss the current status of 3D printing applications in the development of biodegradable cardiovascular implants with a focus on design, biomaterial selection, fabrication methods, and advantages of implantable controlled release systems. Moreover, we delve into the intricate challenges that accompany the clinical translation of these groundbreaking innovations, presenting a glimpse of potential solutions poised to enable the realization of these technologies in the realm of cardiovascular medicine.

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BACKGROUND: Chronic thromboembolic pulmonary hypertension (CTEPH) is a serious disease that can progress and lead to a deadly outcome. Despite optimal drug therapy, pulmonary hypertension (PH) remains fatal. Untreatable right heart failure (RHF) from CTEPH is eventually a significant cause of death. However, unloading the right heart and increasing systemic output are the treatment goals in these patients. CASE PRESENTATION: A 42-year-old female presented to the emergency department with worsening dyspnea experienced for three days before admission. There were also complaints of leg edema, ascites, orthopnea, and palpitation. Physical examination revealed an attenuated second heart sound, abdominal ascites, and bilateral leg edema. She had a history of frequent readmissions due to RHF despite optimal medical therapy and was diagnosed with CTEPH 5 months ago. It was decided that the patient would undergo interatrial septal (IAS) stenting with a vascular stent of 8 mm × 39 mm × 135 cm. The results were good; her symptoms and signs of RHF improved, and she was eventually discharged from the hospital. Four months after the procedure, the patient was able to engage in physical activities without any limitations. CONCLUSIONS: A palliative IAS stent is one of the choices for intractable RHF management in patients with CTEPH. The vascular stent can be used as an alternative in order to make the interatrial connection more stable and last longer.

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

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The interventional therapy of vascular stent implantation is a popular treatment method for cardiovascular stenosis and blockage. However, traditional stent manufacturing methods such as laser cutting are complex and cannot easily manufacture complex structures such as bifurcated stents, while three-dimensional (3D) printing technology provides a new method for manufacturing stents with complex structure and personalized designs. In this paper, a cardiovascular stent was designed, and printed using selective laser melting technology and 316L stainless steel powder of 0-10 µm size. Electrolytic polishing was performed to improve the surface quality of the printed vascular stent, and the expansion behavior of the polished stent was assessed by balloon inflation. The results showed that the newly designed cardiovascular stent could be manufactured by 3D printing technology. Electrolytic polishing removed the attached powder and reduced the surface roughness Ra from 1.36 µm to 0.82 µm. The axial shortening rate of the polished bracket was 4.23% when the outside diameter was expanded from 2.42 mm to 3.63 mm under the pressure of the balloon, and the radial rebound rate was 2.48% after unloading. The radial force of polished stent was 8.32 N. The 3D printed vascular stent can remove the surface powder through electrolytic polishing to improve the surface quality, and show good dilatation performance and radial support performance, which provides a reference for the practical application of 3D printed vascular stent.

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With the advancement of additive manufacturing (AM), customized vascular stents can now be fabricated to fit the curvatures and sizes of a narrowed or blocked blood vessel, thereby reducing the possibility of thrombosis and restenosis. More importantly, AM enables the design and fabrication of complex and functional stent unit cells that would otherwise be impossible to realize with conventional manufacturing techniques. Additionally, AM makes fast design iterations possible while also shortening the development time of vascular stents. This has led to the emergence of a new treatment paradigm in which custom and on-demand-fabricated stents will be used for just-in-time treatments. This review is focused on the recent advances in AM vascular stents aimed at meeting the mechanical and biological requirements. First, the biomaterials suitable for AM vascular stents are listed and briefly described. Second, we review the AM technologies that have been so far used to fabricate vascular stents as well as the performances they have achieved. Subsequently, the design criteria for the clinical application of AM vascular stents are discussed considering the currently encountered limitations in materials and AM techniques. Finally, the remaining challenges are highlighted and some future research directions are proposed to realize clinically-viable AM vascular stents. STATEMENT OF SIGNIFICANCE: Vascular stents have been widely used for the treatment of vascular disease. The recent progress in additive manufacturing (AM) has provided unprecedented opportunities for revolutionizing traditional vascular stents. In this manuscript, we review the applications of AM to the design and fabrication of vascular stents. This is an interdisciplinary subject area that has not been previously covered in the published review articles. Our objective is to not only present the state-of-the-art of AM biomaterials and technologies but to also critically assess the limitations and challenges that need to be overcome to speed up the clinical adoption of AM vascular stents with both anatomical superiority and mechanical and biological functionalities that exceed those of the currently available mass-produced devices.

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