Drug-Coated Balloon Angioplasty vs Plain Balloon Angioplasty in patients with coronary In-Stent Restenosis: A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: In-stent restenosis (ISR) remains a significant challenge in interventional cardiology despite advancements in stent technology. Drug-coated balloons (DCBs), which deliver antiproliferative agents directly to the vessel wall, have emerged as a promising alternative to plain balloon angioplasty for ISR treatment. This meta-analysis evaluates the efficacy of DCBs compared to plain balloon angioplasty in patients with coronary ISR. METHODS: A comprehensive search of PubMed and Embase was conducted on June 27, 2024. The search identified randomized controlled trials comparing DCBs and plain balloon angioplasty for ISR treatment. Six trials involving 1,322 patients met the inclusion criteria. Quality was assessed with the Cochrane Risk of Bias tool. Data extraction and statistical analysis were performed using RevMan software, assessing heterogeneity with the I2 statistic and publication bias using funnel plots. RESULTS: The analysis showed that DCBs significantly reduced late in-stent and in-segment luminal loss (P < 0.001) and target lesion revascularization (P = 0.02) compared to plain balloon angioplasty. Major adverse cardiovascular events and the combined endpoint of target lesion revascularization, myocardial infarction, and death also showed highly significant improvements with DCB treatment (P < 0.00001 and P = 0.0002, respectively). However, no significant effect was observed on myocardial infarction and mortality rates. CONCLUSION: DCBs significantly reduce in-stent late luminal loss, target lesion revascularization, and major adverse cardiovascular events compared to plain balloon angioplasty.

Safety of paclitaxel-coated devices in the femoropopliteal arteries: A systematic review and meta-analysis.

BACKGROUND: Clinical benefit of paclitaxel-coated devices for patients with peripheral arterial disease has been confirmed in randomized controlled trials (RCTs). A meta-analysis published in 2018 identified late mortality risk over a long follow-up period due to use of paclitaxel-coated devices in the femoropopliteal arteries, which caused enormous controversy and debates globally. This study aims to further evaluate the safety of paclitaxel-coated devices by incorporating the most recently published data. METHODS: We searched for candidate studies in PubMed (MEDLINE), Scopus, EMBASE (Ovid) online databases, government web archives and international cardiovascular conferences. Safety endpoints of interest included all-cause mortality rates at one, two and five years and the risk ratio (RR) was used as the summary measure. The primary analysis was performed using random-effects models to account for potential clinical heterogeneity. FINDINGS: Thirty-nine RCTs including 9164 patients were identified. At one year, the random-effects model yielded a pooled RR of 1.06 (95% CI [0.87, 1.29]) indicating no difference in short-term all-cause deaths between the paclitaxel and control groups (crude mortality, 4.3%, 214/5025 versus 4.5%, 177/3965). Two-year mortality was reported in 26 RCTs with 382 deaths out of 3788 patients (10.1%) in the paclitaxel arm and 299 out of 2955 patients (10.1%) in the control arm and no association was found between increased risk of death and usage of paclitaxel-coated devices (RR 1.08, 95% CI [0.93, 1.25]). Eight RCTs recorded all-cause deaths up to five years and a pooled RR of 1.18 (95% CI [0.92, 1.51]) demonstrated no late mortality risk due to use of paclitaxel-coated devices (crude mortality, paclitaxel 18.2%, 247/1360 versus control 15.2%, 122/805). CONCLUSIONS: We found no significant difference in either short- or long-term all-cause mortalities between patients receiving paclitaxel-coated and uncoated devices. Further research on the longer-term safety of paclitaxel usage (e.g., 8- or 10-year) is warranted. REGISTRATION: PROSPERO, CRD42021246291.

Combined Endothelialization Promoting and Surface Binding Chimeric Conjugate with Low Thrombogenicity.

Endothelialization of blood contacting implants, e.g., vascular stents, is regarded as a prerequisite for an improved performance in terms of minimizing thrombogenicity and the inhibition of restenosis. Commonly used materials, such as Ti-based alloys, can be surface-modified in order to improve endothelial cell (EC) colonization as well as to reduce platelet adhesion. Standard modification techniques involve silanization and are laborious and time-consuming. We propose a novel single-step procedure based on a surface-recognizing peptide generated by phage display methodology. Combining this with a polyethylene glycol (PEG) spacer and an EC-specific sequence yielded a conjugate applicable for the modification of Ti surfaces.

Deep brain stimulation: Challenges at the tissue-electrode interface and current solutions.

Deep brain stimulation (DBS) is used to treat the motor symptoms of Parkinson's disease patients by stimulating the subthalamic nucleus. However, optimization of DBS is still needed since the performance of the neural electrodes is limited by the body's response to the implant. This review discusses the issues with DBS, such as placement of electrodes, foreign body response, and electrode degradation. The current solutions to these technical issues include modifications to electrode material, coatings, and geometry.

Enhanced Hemocompatibility of a Direct Chemical Vapor Deposition-Derived Graphene Film.

A wide range of biomedical devices are being used to treat cardiovascular diseases, and thus they routinely come into contact with blood. Insufficient hemocompatibility has been found to impair the functionality and safety of these devices through the activation of blood coagulation and the immune system. Numerous attempts have been made to develop surface modification approaches of the cardiovascular devices to improve their hemocompatibility. However, there are still no ideal "blood-friendly" coating materials, which possess the desired hemocompatibility, tissue compatibility, and mechanical properties. As a novel multifunctional material, graphene has been proposed for a wide range of biomedical applications. The chemical inertness, atomic smoothness, and high durability make graphene an ideal candidate as a surface coating material for implantable devices. Here, we evaluated the hemocompatibility of a graphene film prepared on quartz glasses (Gra-glasses) from a direct chemical vapor deposition process. We found that the graphene coating, which is free of transfer-mediating polymer contamination, significantly suppressed platelet adhesion and activation, prolonged coagulation time, and reduced ex vivo thrombosis formation. We attribute the excellent antithrombogenic properties of the Gra-glasses to the low surface roughness, low surface energy (especially the low polar component of the surface energy), and the negative surface charge of the graphene film. Given these excellent hemocompatible properties, along with its chemical inertness, high durability, and molecular impermeability, a graphene film holds great promise as an antithrombogenic coating for next-generation cardiovascular devices.

Protecting the skin-implant interface with transcutaneous silver-coated skin-and-bone-integrated pylon in pig and rabbit dorsum models.

Implant-associated soft tissue infections at the skin-implant interface represent the most frequent complications in reconstructive surgery and lead to implant failures and revisions. Titanium implants with deep porosity, called skin-and-bone-integrated-pylons (SBIP), allow for skin ingrowth in the morphologically natural direction, thus restoring a reliable dermal barrier and reducing the risk of infection. Silver coating of the SBIP implant surface using physical vapor deposition technique offers the possibility of preventing biofilm formation and exerting a direct antimicrobial effect during the wound healing phase. In vivo studies employing pig and rabbit dorsum models for assessment of skin ingrowth into the pores of the pylon demonstrated the safety of transcutaneous implantation of the SBIP system. No postoperative complications were reported at the end of the follow-up period of 6 months. Histological analysis proved skin ingrowth in the minipig model without signs of silver toxicity. Analysis of silver release (using energy dispersive X-ray spectroscopy) in the model of intramedullary-inserted silver-coated SBIP in New Zealand rabbits demonstrated trace amounts of silver after 3 months of in-bone implantation. In conclusion, selected temporary silver coating of the SBIP implant surface is powerful at preventing the periprosthetic infections without imparing skin ingrowth and can be considered for clinical application.

Biocompatibility and stability during storage of Foley urinary catheters coated chlorhexidine loaded nanoparticles by nanocoating: in vitro and in vivo evaluation.

Foley urinary catheters were coated by chlorhexidine-loaded micelles and chlorhexidine-loaded nanospheres. In our prior study, the nanocoating of Foley urinary catheter was investigated for chlorhexidine-release study, degradation, antibacterial evaluation, and cytotoxicity assessment. These studies presented the 1 month antibacterial property of nanocoating deposited via the layers of micelles and nanospheres. In this study, we evaluated the biocompatibility of these catheters, including hemocompatibility, skin irritation, skin sensitization, and stability during the age of coated urinary catheter. Results demonstrated that coated urinary catheters presented slight hemolysis, whereas skin irritation on rabbit and skin sensitization on Dunkin Hartley guinea pig showed no signs of dermal toxicity, which indicated that inflammation, redness, and swelling did not occur. Moreover, the stability of coated urinary catheters during storage indicated no change in chlorhexidine peaks by high performance liquid chromatography. Information from these studies supports the biocompatibility of coated urinary catheters via nanocoating and their use as indwelling devices to prevent urinary tract infections.

Behaviour of Vascular Smooth Muscle Cells on Amine Plasma-Coated Materials with Various Chemical Structures and Morphologies.

Amine-coated biodegradable materials based on synthetic polymers have a great potential for tissue remodeling and regeneration because of their excellent processability and bioactivity. In the present study, we have investigated the influence of various chemical compositions of amine plasma polymer (PP) coatings and the influence of the substrate morphology, represented by polystyrene culture dishes and polycaprolactone nanofibers (PCL NFs), on the behavior of vascular smooth muscle cells (VSMCs). Although all amine-PP coatings improved the initial adhesion of VSMCs, 7-day long cultivation revealed a clear preference for the coating containing about 15 at.% of nitrogen (CPA-33). The CPA-33 coating demonstrated the ideal combination of good water stability, a sufficient amine group content, and favorable surface wettability and morphology. The nanostructured morphology of amine-PP-coated PCL NFs successfully slowed the proliferation rate of VSMCs, which is essential in preventing restenosis of vascular replacements in vivo. At the same time, CPA-33-coated PCL NFs supported the continuous proliferation of VSMCs during 7-day long cultivation, with no significant increase in cytokine secretion by RAW 264.7 macrophages. The CPA-33 coating deposited on biodegradable PCL NFs therefore seems to be a promising material for manufacturing small-diameter vascular grafts, which are still lacking on the current market.

Preclinical studies of non-stick thin film metallic glass-coated syringe needles.

Our objective in this study was to determine the biocompatibility and hemocompatibility of thin film metallic glass (TFMG) and its potential use in hypodermic needles for intramuscular or intravenous injection. Mouse and rabbit models were employed under approval from the Institutional Animal Care and Use Committee (n = 5/group, two groups in total for both animal models). Platelet-rich plasma (PRP) was collected from the whole blood of rabbits (ear vein) without anti-coagulant for use in in vitro coagulation tests. Histological analysis and optical microscopy were used to assess the endothelial structure of the inner lining of veins after being punctured with needles and detained for 3 days. Histological analysis of ear vein sections revealed that the extent of endothelial damage after puncturing with a TFMG-coated needle was 33% less than that produced by bare needles. Our results confirm that the deposition of a thin TFMG layer (e.g., Zr53Cu33Al9Ta5) on the surface of hypodermic needle can have remarkably clinical benefits, including anti-adhesion, reduced invasion, and minimal endothelial damage. Our results also confirm the good biocompatibility and hemocompatibility of the TFMG coatings.

Surface coating and speckling of the human iliotibial tract does not affect its load-deformation properties.

Stochastic surface patterns form an important requirement to facilitate digital image correlation and to subsequently quantify material properties of various tissues when loaded and deformed without artefacts arising from material slippage. Depending on the samples' natural colour, a surface pattern is created by speckling with colour or dye only, or it requires combined surface coating and speckling before to enhance the contrast, to facilitate high-quality data recording for mechanical evaluation. However, it is unclear to date if the colours deployed for coating and speckling do significantly alter the biomechanical properties of soft tissues. The given study investigated the biomechanical properties of 168 human iliotibial tract samples as a model for collagen-rich soft tissues, separated into four groups: untreated, graphite speckling only, water-based coating plus graphite speckling and solvent-based coating plus graphite speckling following a standardized approach of application and data acquisition. The results reveal that elastic modulus, ultimate tensile strength and strain at maximum force of all groups were similar and statistically non-different (p ≥ 0.69). Qualitatively, the speckle patterns revealed increasing contrast differences in the following order: untreated, graphite speckling only, water-based coating plus graphite speckling and solvent-based coating plus graphite speckling. Conclusively, both coating by water- and solvent-based paints, as well as exclusive graphite speckling, did not significantly influence the load-deformation parameters of the here used human iliotibial tract as a model for collagen-rich soft tissues. In consequence, water- and solvent-based coating paints seem equally suitable to coat collagen-rich soft tissues for digital image correlation, resulting in suitable speckle patterns and unbiased data acquisition.

In Vitro and In Vivo Biocompatibility Studies of a Cast and Coated Titanium Alloy.

The biocompatibility of a cast porous and with a calcium titanate reaction layer functionalized titanium alloy (Ti-6Al-7Nb) was tested by means of cell culture, and a small (rat) and large animal (sheep) model. The uncoated titanium material served as a control. In-vitro tests included the validation of osteoblast-like cells attached to the surface of the material with scanning electron microscopy and immunofluorescence of cytoskeletal actin as well as their osteogenic development, the ability to mineralize, and their vitality. Following the in-vitro tests a small animal (rat) and big animal (sheep) model were accomplished by inserting a cylindrical titanium implant into a drill hole defect in the femoral condyle. After 7, 14, and 30 days (rat) and 6 months (sheep) the condyles were studied regarding histological and histomorphometrical characteristics. Uncoated and coated material showed a good biocompatibility both in cell culture and animal models. While the defect area in the rat is well consolidated after 30 days, the sheep show only little bone inside the implant after 6 months, possibly due to stress shielding. None of the executed methods indicated a statistically significant difference between coated and uncoated material.

Multilayering as a solution to medical device failure.

There are three main problems associated with medical device implants: biofilm, wear and corrosion, and bio rejection. A potential solution to these problems is multilayering. Polyelectrolyte multilayered films composed of polyallylamine hydrochloride and poly(4-vinylphenol) have been demonstrated to inhibit Staphylococcus epidermidis growth. Another study examined the wear behavior of polyelectrolyte multilayer coated orthopedic surfaces composed of poly(acrylic acid) and poly(allylamine hydrochloride) and found coated systems resulted in 33 % less wear than uncoated systems. Additionally, a heparin/collagen anti-CD34 antibody ((HEP/COL)5-CD34) multilayer system provided accelerated adhesion of endothelial cells with a significant number of endothelial cells attaching in the first 5 min. This allowed for re-endothelialization to occur possibly reducing cardiac stent bio rejection. This review explores various ways multilayering has been utilized to prolong medical device use and decrease the number of complications associated with them.

Optimized drug-coated balloon angioplasty of the superficial femoral and proximal popliteal arteries using the Tack Endovascular System: TOBA III 12-month results.

OBJECTIVE: The Tack Endovascular System (Intact Vascular, Wayne, Pa) combines low-metallic content with focal delivery to seal areas of dissection associated with balloon angioplasty. The device system is designed to treat vascular dissections in the superficial femoral and proximal popliteal arteries. Tack implants exert low radial force and are associated with minimal metal burden, which reduces the mechanical stress on the arterial wall in treating dissections after balloon angioplasty. This study investigated the safety and effectiveness of the Tack Endovascular System in patients with dissections after drug-coated balloon (DCB) angioplasty. METHODS: The Tack Optimized Balloon Angioplasty III (TOBA III) study is a prospective, multicenter, single-arm study in which patients who underwent percutaneous transluminal angioplasty with the Medtronic IN.PACT Admiral DCB (Medtronic, Dublin, Ireland) and experienced dissection after angioplasty were treated with Tack implants. The primary end points were freedom from major adverse events at 30 days and primary patency at 12 months. RESULTS: A total of 201 patients were enrolled in the trial, 169 with standard-length lesions (≥20 mm and ≤150 mm) and 32 with long-length lesions (>150 mm and ≤250 mm). Safety and effectiveness results were favorable compared with historical benchmarks at 12 months in the standard-lesion cohort. Notably, patients in the standard-lesion cohort experienced 95.0% primary patency, 97.5% freedom from clinically driven target lesion revascularization, 100% freedom from amputation, and 100% survival at 12 months (P < .0001). Primary patency in long-lesion patients was 89.3%, freedom from clinically driven target lesion revascularization was 96.8%, and freedom from amputation was 100% at 12 months. Device success was achieved in 95.8% (182/190) and 97.7% (43/44) of devices deployed into standard-lesion and long-lesion patients, respectively. Procedural success was 99.4% (168/169) and 100% (44/44) in the standard-lesion and long-lesion cohorts, respectively, with only one bailout stent placed in the entire population. CONCLUSIONS: The Tack Endovascular System is a safe and effective treatment option for patients with dissections after angioplasty in the superficial femoral and proximal popliteal arteries, with high patency, low rates of secondary intervention, and low incidence of bailout stenting when it is used in combination with DCB.

[Influence of unmodified and modified sutures on experimental abdominal adhesive process]. / Éksperimental'naia otsenka spaechnogo protsessa v briushnoi polosti pri ispol'zovanii nemodifitsirovannogo shovnogo materiala i modifitsirovannogo geparinom.

OBJECTIVE: Experimental assessment of the effect of modified and unmodified surgical suture material on abdominal adhesive process. MATERIAL AND METHODS: The study was performed on male rats of the Wistar subpopulation. There were 5 animals in each group. In all animals, midline abdominal incision was followed by suturing the parietal peritoneum with modified and unmodified suture material. All animals were euthanized with carbon dioxide vapors in 14 days after surgery. Macro- and microscopic assessment of severity of abdominal adhesive process was carried out. Two types of preparation of excised complexes 'peritoneum-suture material-adhesion' were applied for histological examination: paraffin sections and embedding in epoxy resin. Specimens were stained by Van Gieson and with methylene blue solution. Histological specimens were examined using Axio Imager A1 light microscope (Zeiss, Germany). RESULTS: Polypropylene filaments result extensive adhesions occupying about 75% of the area. Adhesions have a dense structure with signs of vascularization. Modification of suture material with solution of polyhydroxybutyrate/hydroxyvalerate and heparin reduce severity of adhesions. The use of modified suture material was followed by adhesions with more loose structure, no signs of vascularization. Adhesions occupied less than 25% of the area. Histological examination of excised complexes 'peritoneum-suture material-adhesion' revealed accumulation of inflammatory cells around the unmodified suture material, while there were no signs of tissue inflammatory process around the modified sutures. CONCLUSION: Application of polyhydroxybutyrate/hydroxyvalerate and heparin on the surface of surgical sutures is an effective method for prevention of abdominal adhesions.

Drug-coated balloon versus conventional balloon angioplasty of hemodialysis arteriovenous fistula or graft: A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Restenosis remains a significant problem in endovascular therapy for hemodialysis vascular access. Drug-coated balloon (DCB) angioplasty decreases restenosis in peripheral and coronary artery diseases. The aim of this systematic review and meta-analysis is to assess the patency outcomes following DCB angioplasty, as compared to conventional balloon (CB) angioplasty for the stenosis of hemodialysis vascular access. METHODS: A comprehensive search in the MEDLINE, EMBASE, and CENTRAL databases was conducted in order to identify eligible randomized controlled trials evaluating DCB angioplasty for hemodialysis vascular access dysfunction. The primary endpoint was the 6-month target lesion primary patency and the secondary endpoints were 12-month target lesion primary patency and procedure-related complications. Risk ratios (RR) were pooled and relevant subgroups were analyzed separately. RESULTS: Eleven randomized controlled trials comprised of 487 patients treated with DCB angioplasty and 489 patients treated with CB angioplasty were included. There were no significant differences in the target lesion primary patency at 6 months [RR, 0.75; 95% confidence interval (CI), 0.56, 1.01; p = 0.06] and at 12 months (RR 0.89; 95% CI, 0.79, 1.00; p = 0.06). The absence of benefit for the DCB group remained, even in the arteriovenous fistula subgroup or the subgroup of studies excluding central vein stenosis. The risk of procedure-related complication did not differ between the two groups (RR 1.00; 95% CI 0.98, 1.02; p = 0.95). CONCLUSION: DCB angioplasty did not demonstrate significant patency benefit for the treatment of hemodialysis vascular access dysfunction. Wide variations in patency outcomes across studies were noted. Further studies focusing on specific types of access or lesions are warranted to clarify the value of DCB for hemodialysis vascular access. (PROSPERO Number CRD42019119938).