Search Results (142)

Thoracic endovascular aortic repair (TEVAR) for cardiovascular diseases often encounters complications that are closely linked to the mechanical properties of stent-grafts. Both the design and material properties influence device performance, but the specific impacts of material properties remain underexplored and poorly understood. This study aims to fill this gap by systematically investigating how material science can modulate stent-graft mechanics. Four types of bare nitinol stents combined with expanded polytetrafluoroethylene (e-PTFE) or polyethylene terephthalate (PET) grafts were modeled via finite element analysis, creating eight stent-graft configurations. Key mechanical properties—flexibility, crimpability, and fatigue performance—were evaluated to dissect material effects. The results revealed that nitinol’s properties significantly influenced all performance metrics, while PET grafts notably enhanced flexibility and fatigue life. No significant differences in equivalent stress were found between PET and e-PTFE grafts, and both had minimal impacts on radial force. This work underscores the potential of material science-driven optimization to enhance stent-graft performance for improved clinical outcomes. Full article

Optical Coherence Tomography (OCT) is a further light-based intravascular imaging modality and provides a high-resolution, cross-sectional view of coronary arteries. It has a useful anatomic and increasingly physiological evaluation in light of coronary artery disease (CAD). This review provides a critical examination of the increased application of the OCT in assessing coronary artery physiology, beyond its initial mainstay application in anatomical imaging. OCT provides precise information on plaque morphology, which can help identify vulnerable plaques, and is most important in informing percutaneous coronary interventions (PCIs), including implanting a stent and optimizing it. The combination of OCT and functional measurements, such as optical flow ratio and OCT-based fractional flow reserve (OCT-FFR), permits a more complete assessment of coronary stenoses, which may provide increased diagnostic accuracy and better revascularization decision-making. The recent developments in OCT technology have also enhanced the accuracy in the measurement of coronary functions. The innovations may support the optimal treatment of patients as they provide more personalized and individualized treatment options; however, it is critical to recognize the limitations of OCT and distinguish between the hypothetical advantages and empirical outcomes. This review evaluates the existing uses, technological solutions, and future trends in OCT-based physiological imaging and evaluation, and explains how such an advancement will be beneficial in the treatment of CAD and gives a fair representation concerning other imaging applications. Full article

Chronic Coronary Syndrome (CCS) significantly impacts quality of life and increases the risk of adverse cardiovascular events, remaining the leading cause of mortality worldwide. The use of sensor technology in medicine is emerging as a promising approach to enhance the management and monitoring of patients across a wide range of diseases. Recent advancements in engineering and nanotechnology have enabled the development of ultra-small devices capable of collecting data on critical physiological parameters. Several sensors integrated in wearable and implantable devices, instruments for exhaled gas analysis, smart stents and tools capable of real time biochemical analysis have been developed, and some of them have demonstrated to be effective in CCS management. Their application in CCS could provide valuable insights into disease progression, ischemic events, and patient responses to therapy. Moreover, sensor technologies can support the personalization of treatment plans, enable early detection of disease exacerbations, and facilitate prompt interventions, potentially reducing the need for frequent hospital visits and unnecessary invasive diagnostic procedures such as coronary angiography. This review explores sensor integration in CCS care, highlighting technological advances, clinical potential, and implementation challenges. Full article

Objective: This article presents a step-by-step digital technique for fabricating a 3D-printed surgical guide to assist in alveoloplasty for immediate denture placement. Methods: The workflow integrates intraoral scanning, virtual tooth extraction, digital soft tissue modeling, and additive manufacturing to produce a customized guide with an occlusal window and buccal slot, along with a verification stent. Results: This method ensures precise ridge recontouring and verification, enhancing surgical predictability and prosthetic fit. Conclusions: Unlike traditional surgical guides based on conventional casts or manual fabrication, this fully digital approach offers a practical and replicable protocol that bridges digital planning and clinical execution. By improving surgical precision, reducing operative time, and ensuring optimal denture fit, this technique represents a significant advancement in guided pre-prosthetic surgery. Full article

Bioabsorbable polymer stents (BPSs) were developed to address the long-term clinical drawbacks associated with permanent metallic stents by gradually dissolving over time before these drawbacks have time to develop. However, the polymers used in BPSs, such as polylactic acid (PLA), have lower mechanical properties than metals, often requiring larger struts to provide the necessary structural support. These larger struts have been linked to delayed endothelialisation and an increased risk of stent thrombosis. To address this limitation, this study investigated the incorporation of high-strength basalt fibres into PLA to enhance its mechanical performance, with an emphasis on optimising the processing conditions to achieve notable improvements at minimal fibre loadings. In this regard, PLA/basalt fibre composites were prepared via twin-screw extrusion at screw speeds of 50, 200, and 350 RPM. The effects were assessed through ash content testing, tensile testing, SEM, and rheometry. The results showed that lower screw speeds achieved adequate fibre dispersion while minimising the molecular weight reduction, leading to the most substantial improvement in the mechanical properties. To examine whether a second extrusion run could enhance the fibre dispersion, improving the composite’s uniformity and, therefore, mechanical enhancement, all the batches underwent a second extrusion run. This run improved the dispersion, leading to increased strength and an increased modulus; however, it also reduced the fibre–matrix adhesion and resulted in a notable reduction in the molecular weight. The highest mechanical performance was observed at 10% fibre loading and 50 RPM following a second extrusion run, with the tensile strength increasing by 20.23% and the modulus by 27.52%. This study demonstrates that the processing conditions can influence the fibres’ effectiveness, impacting dispersion, adhesion, and molecular weight retention, all of which affect this composite’s mechanical performance. Full article

Vein graft restenosis remains a major complication following coronary artery bypass grafting (CABG), mainly due to the abnormal proliferation of vascular smooth muscle cells (VSMCs) and impaired endothelial repair. While external stents (eStents) can provide mechanical support and limit adverse remodeling, traditional metallic stents are non-degradable and may induce chronic inflammation and fibrosis. In contrast, many bioresorbable materials degrade too quickly or lack mechanical strength. These challenges highlight the need for external stents that combine sufficient mechanical strength with biodegradability to support long-term graft patency. This is the first study that develops a chlorogenic acid–strontium (SrCA)-loaded polycaprolactone bioresorbable eStent that inhibits VSMC proliferation and enhances endothelial repair via Hippo–Yes-associated protein (YAP) signaling, addressing vein graft restenosis post-CABG. Combining mechanical support and biodegradability, it overcomes the limitations of non-degradable stents and rapidly degrading biomaterials, elucidates the potential of natural polyphenol–metal ion complexes in vascular remodeling, and offers an innovative strategy for the prevention of vein graft restenosis. Full article

The natural history of focal non-infected lesions of the abdominal aorta (fl-AA) remains unclear and largely depends on their aetiology. These lesions often involve a focal “tear” or partial disruption of the arterial wall. Penetrating aortic ulcers (PAUs) and intramural hematomas (IMHs) are examples of focal tears in the aortic wall that can either progress to dilatation (saccular aneurysm) or fail to fully propagate through the medial layers, potentially leading to aortic dissection. These conditions typically exhibit a morphology consistent with eccentric saccular aneurysms. The management of focal non-infected pathologies of the abdominal aorta remains a subject of debate. Unlike fusiform abdominal aortic aneurysms, the inconsistent definitions and limited information regarding the natural history of saccular aneurysms (sa-AAAs) have prevented the establishment of universally accepted practice guidelines for their management. As emphasized in the latest 2024 ESVS guidelines, the focal nature of these diseases makes them ideal candidates for endovascular repair (class of evidence IIa—level C). Moreover, the Society for Vascular Surgery just referred to aneurysm diameter as an indication for treatment suggesting using a smaller diameter compared to fusiform aneurysms. Consequently, the management of saccular aneurysms is likely heterogeneous amongst different centres and different operators. Endovascular repair using tube stent grafts offers benefits like reduced recovery times but carries risks of migration and endoleak due to graft rigidity. These complications can influence long-term success. In this context, the use of endovascular bifurcated grafts may provide a more effective solution for treating these focal aortic pathologies. It is essential to achieve optimal sealing regions through anatomical studies of aortic morphology. Additionally, understanding the anatomical characteristics of focal lesions in challenging necks or para-visceral locations is indeed crucial in device choice. Off-the-shelf devices are favoured for their time and cost efficiency, but new endovascular technologies like fenestrated endovascular aneurysm repair (FEVAR) and custom-made devices enhance treatment success and patient safety. These innovations provide stent grafts in various lengths and diameters, accommodating different aortic anatomies and reducing the risk of type III endoleaks. Although complicated PAUs and focal saccular aneurysms rarely arise in the para-visceral aorta, the consequences of rupture in this segment might be extremely severe. Experience borrowed from complex abdominal and thoracoabdominal aneurysm repair demonstrates that fenestrated and branched devices can be deployed safely when anatomical criteria are respected. Elective patients derive the greatest benefit from a fenestrated graft, while urgent cases can be treated confidently with off-the-shelf multibranch systems, reserving other types of repairs for emergent or bail-out cases. While early outcomes of these interventions are promising, it is crucial to acknowledge that limited aortic coverage can still impede effective symptom relief and lead to complications such as aneurysm expansion or rupture. Therefore, further long-term studies are essential to consolidate the technical results and evaluate the durability of various graft options. Full article

Chronic rhinosinusitis (CRS) is a prevalent inflammatory condition of the nasal and paranasal mucosa that significantly impacts the quality of life. Postoperative inflammation and polyp recurrence remain common despite advances in endoscopic sinus surgery (ESS), prompting interest in localized corticosteroid delivery systems. This review analyzes bioresorbable steroid-releasing implants and corticosteroid-impregnated nasal dressings, focusing on their pharmacologic mechanisms, safety, and clinical outcomes. A synthesis of findings from randomized trials and observational studies was performed, with emphasis on devices such as Propel™, NasoPore, Merocel, SinuBand FP, and gel-based dressings. The Propel implant demonstrated robust evidence for reducing adhesions and inflammation with negligible systemic absorption. NasoPore and Merocel provided structural support and localized steroid delivery but lacked controlled-release kinetics. Gel-based dressings and SinuBand FP offered anatomic adaptability, with limited systemic effects. Some methods showed systemic steroid exposure in cortisol monitoring. Corticosteroid-releasing devices enhance ESS outcomes through localized therapy. While Propel is the most validated, other devices remain viable alternatives in specific clinical contexts. Comprehensive safety monitoring and standardized trials are essential to optimize their integration into postoperative care. Full article

Biodegradable vascular stents (BVSs) face challenges related to inadequate mechanical strength, which can lead to adverse clinical outcomes. Improving the mechanical behavior of biodegradable vascular stents through structural design has been extensively explored. However, the corresponding effects of these mechanical enhancements on degradation characteristics remain under-investigated. The present work focuses on examining how different stent design strategies affect the mechanical behavior and degradation characteristics of poly (lactic acid) (PLA) stents. The commercial PLA stent DESolve was adopted, and nine modified stents were constructed based on the geometrical configuration of the DESolve stent. The mechanical properties of the modified stents during radial crimping and three-point bending simulations were thoroughly studied. The degradation dynamics of the stents were characterized by four indices (i.e., mean number average molecular weight, residual volume fraction, mean von Mises stress, and stent diameter). The results indicated that both the widening ratio and direction affected the mechanical performance of the stents by increasing the radial stiffness and radial strength, minimizing recoil%, and decreasing the bending flexibility. Although the widening direction had a relatively minor influence on stent degradation, the associated increase in material volume contributed to an improved volumetric integrity and enhanced lumen preservation. This study established a theoretical basis for evaluating both the mechanical and degradation behaviors of PLA stents, offering valuable insights for future structural design optimization. Full article

Intravascular imaging (IVI) has emerged as a pivotal tool in percutaneous coronary intervention (PCI), offering superior visualization of coronary anatomy compared with conventional angiography. This literature review synthesizes the latest evidence from randomized trials and meta-analyses published since 2022, assessing the comparative efficacy of IVI modalities—including intravascular ultrasound (IVUS) and optical coherence tomography (OCT)—in complex coronary lesions. Multiple landmark trials, such as RENOVATE-COMPLEX PCI, ILUMIEN IV, OCTOBER, and OCTIVUS, demonstrated that IVI-guided PCI significantly improves procedural outcomes, stent optimization, and clinical endpoints such as target-vessel failure, myocardial infarction, and stent thrombosis. OCT was shown to be particularly beneficial in bifurcation and left main interventions, while IVUS consistently improved outcomes in long lesions and complex anatomies. Despite some trials not meeting their primary clinical endpoints, substudy findings and pooled analyses support a shift toward routine IVI use in anatomically complex cases. Consequently, updated guidelines now recommend IVI as a Class I indication in select patient populations. These findings underscore the need for broader clinical adoption and training in IVI techniques to enhance PCI outcomes. Full article

Magnesium alloy stents exhibit significant potential in the treatment of cardiovascular and cerebrovascular diseases due to their remarkable mechanical support and biodegradability. However, bare magnesium alloy stents often degrade too quickly and exhibit inadequate biocompatibility, which severely restricts their clinical applicability. Herein, a composite coating consisting of an MgF₂ conversion layer, a polydopamine (PDA) layer, fucoidan, and hyaluronic acid was prepared to enhance the corrosion resistance and biocompatibility of ZE21B alloy for a vascular stent application. The modified ZE21B alloy exhibited relatively high surface roughness, moderate wettability, and better corrosion resistance. Moreover, the modified ZE21B alloy with a low hemolysis rate and fibrinogen adsorption level confirmed improved hemocompatibility for medical requirements. Furthermore, the ZE21B alloy modified with fucoidan and hyaluronic acid enhanced the adhesion, proliferation, and NO release of endothelial cells (ECs). Simultaneously, it inhibits the adhesion and proliferation of smooth muscle cells (SMCs), promoting a competitive advantage for ECs over SMCs due to the synergistic effects of fucoidan and hyaluronic acid. The incorporation of fucoidan and hyaluronic acid markedly improved the corrosion resistance and biocompatibility of the ZE21B magnesium alloy. This development presents a straightforward and effective strategy for the advancement of biodegradable vascular stents. Full article

Background: Pancreatic stents (PSs) play a crucial role in the management of pancreatic duct obstructions, particularly in the context of endoscopic retrograde cholangiopancreatography (ERCP). However, stent migration remains a significant complication, leading to risks such as pancreatitis, pancreatic duct stenosis, and abscess formation. This study aims to evaluate the efficacy of various endoscopic techniques for retrieving proximally migrated or broken pancreatic stents, highlighting optimal strategies for improving patient outcomes. Methods: A retrospective multicenter review was conducted across six hospitals from 2016 to 2024. Patients with proximally migrated or broken pancreatic stents referred for endoscopic retrieval after failed attempts at other facilities were included. Demographic data, stent characteristics, and retrieval techniques were analyzed. Endoscopic methods included SpyGlass forceps, SpyGlass baskets, Soehendra retriever stents, balloon sweeps, flower baskets, and extension pancreatic sphincterotomy. Procedural success, retrieval times, and post-procedural outcomes were assessed. Results: Twelve patients underwent endoscopic retrieval, including two with broken stents. All procedures were successful, with retrieval times averaging 30 to 45 min. Two patients developed pancreatic duct narrowing, requiring balloon dilation. All patients had new stents placed to maintain duct patency, and no major complications were observed. Follow-up evaluations confirmed complete resolution of migration-related issues, with all stents removed. Conclusions: Endoscopic retrieval of migrated pancreatic stents is highly effective, with specialized techniques ensuring a 100% success rate in this study. Early intervention and the selection of appropriate retrieval methods are critical in minimizing complications. Further research is needed to refine retrieval strategies and standardize protocols to enhance clinical outcomes. Full article

Background/Objectives: Fast-track (FT) protocols have been developed to reduce the surgical burden and enhance recovery, but they still need to be established for carotid endarterectomy (CEA). In this scenario, carotid stenting has gained momentum by answering the need for a less invasive treatment, despite a still debated clinical advantage. We aim to propose a FT protocol for CEA and to analyze its clinical outcomes. Methods: This retrospective, monocentric study enrolled consecutive patients who underwent CEA for asymptomatic carotid stenosis using an FT protocol between January 2016 and December 2024. Patients undergoing CEA for symptomatic carotid stenosis, carotid bypass procedures, and combined interventions were excluded. Our FT protocol comprises same-day hospital admission, exclusive use of local anesthesia, non-invasive assessment of cardiac and neurological status, and selective utilization of cervical drainage. Discharge criteria were goal-directed and included the absence of pain, electrocardiographic abnormalities, hemodynamic instability, neck hematoma, or cranial nerve injury, with a structured plan for rapid readmission if required. Postoperative pain was assessed using the numerical rating scale (NRS), administered to all patients. The perioperative clinical impact of the protocol was evaluated based on complication rates, pain control, length of hospital stay, and early readmission rates. Results: Among 1051 patients who underwent CEA, 853 met the inclusion criteria. General anesthesia was required in 17 cases (2%), while a cervical drain was placed in 83 patients (10%). The eversion technique was employed in 765 cases (90%). Postoperative intensive care unit (ICU) monitoring was necessary for 7 patients (1%). The mean length of hospital stay was 1.17 days. Postoperatively, 17 patients (2%) required surgical revision. Minor stroke occurred in three patients (0.4%), and acute myocardial infarction requiring angioplasty in two patients (0.2%). Inadequate postoperative pain control (NRS > 4) was reported by five patients (0.6%). Hospital readmission was required for one patient due to a neck hematoma. Conclusions: The reported fast-track protocol for elective carotid surgery was associated with a low rate of postoperative complications. These findings support its clinical value and highlight the need for further validation through controlled comparative studies. Furthermore, the implementation of fast-track protocols in carotid surgery should prompt comparative medico-economic research. Full article

Magnesium-based coronary stents have gained significant interest due to their excellent biocompatibility, biodegradability, and mechanical properties. However, a key limitation of magnesium in biomedical applications is its low corrosion resistance, which compromises its structural integrity and mechanical strength over time. Polymeric coatings can overcome this challenge, enhancing magnesium-based implants’ corrosion resistance and overall performance. This study applied a polylactic acid (PLA) nanofiber coating to WE43 magnesium (Mg) stents via electrospinning to reduce their corrosion rate. Both uncoated and coated stents underwent in vitro immersion tests in Hank’s solution for 1, 3, 7, and 14 days. The effectiveness of the PLA coating was evaluated through morphological analysis, chemical composition assessment, corrosion behavior (weight change), magnesium ion release, and in vitro biocompatibility. The corrosion observed in the uncoated WE43 stents indicates that protective coatings are necessary to regulate degradation rates over extended implantation periods. The results demonstrated that coated stents exhibited improved performance, maintaining the integrity of the PLA coating for up to 14 days. The coated stents demonstrated reduced surface damage and lower weight loss resulting from lower magnesium release. In our study, the coated stents demonstrated a reduced corrosion rate (0.216 ± 0.013 mm/year) compared with the uncoated stents (0.312 ± 0.010 mm/year), both after 14 days. Additionally, in vitro biocompatibility results confirmed the non-toxic nature of PLA-coated stents, which enhances cellular proliferation and contributes to a more favorable environment for vascular healing. These findings suggest that PLA coatings can effectively prolong the functional durability of WE43 Mg stents, offering a promising solution for enhancing the performance of biodegradable stents in cardiovascular applications. Full article

This study aimed to assess the clinical value of three-dimensional printed personalised vascular models (3DPPVMs) in assisting with the pre-operative planning and simulation of endovascular interventions. CT angiographic images of four cases, namely, abdominal aorta aneurysm (AAA), carotid artery stenosis, coronary artery stenosis, and renal artery stenosis, were selected, and 3DPPVMs were obtained. A total of 21 clinicians specialising in interventional radiology and vascular surgery were invited to participate in the study, comprising 6 radiologists and 15 vascular surgeons. Of these, 66.7% had not used a 3DPPVM prior to their participation. Considering all areas of experience and all four models, it was observed that 75% of the participants gave a ranking of 7 or above out of 10 with regard to the recommendation of the use of the 3DPPVMs. The mean scores of the participants’ ranking of the models ranged from 3.2 to 4.3 out of 5. The AAA model was ranked the highest for realism (4.10 ± 0.89, p = 0.002), the planning of interventions and simulations (3.90 ± 1.12 and 4.05 ± 0.95), the development of haptic skills (3.56 ± 0.98), reducing the procedure time (3.47 ± 1.12), and clarifying the pathology to patients (4.33 ± 0.69, p all >0.05), indicating consistency amongst the participants. The carotid artery model was ranked the highest for accurately displaying anatomical structures (4.3 ± 0.73). All the 3DPPVMs enhanced the understanding of the disease demonstrated, with rankings between 3.8 and 3.95. All the models aided in elucidating the intervention procedure required and in the planning of vascular interventions, with rankings of 3.5 and 3.9. The highest rankings were given by qualified clinicians with 8 or more years of experience. This study shows the potential value of using 3D-printed vascular models in education for clinicians and patients, as well as for clinical training and the pre-surgical simulation of endovascular stent-grafting procedures. Full article