Search Results (8)

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

Newborns with congenital heart disease often require interventions linked to high morbidity and mortality rates. In the last few decades, many transcatheter interventions have become the first-line treatments for some critical conditions in the neonatal period. A catheter-based approach provides several advantages in terms of procedural time, length of hospitalization, repeatability and neurodevelopmental issues (usually related to cardiopulmonary bypass). The main transcatheter procedures will be reviewed, as they are now valid alternatives to conventional surgical management. Full article

Introduction. Pancreatic ductal adenocarcinoma (PDA) is associated with poor prognosis and 98% loss-of-life expectancy. 80% of patients with PDA are unfit for radical surgery. In those cases, emphasis is set on management of cancer-related symptoms, among which obstructive jaundice is most common. Endoscopic ultrasound-guided biliary drainage (EUS-BD) emerges as a valid alternative to the well-accepted methods for treatment of biliary obstruction. Patient Selection. Five consecutive patients with unresectable pancreatic malignancy, were subjected to EUS-BD, particularly EUS-guided choledochoduodenostomy (EUS-CDS). Ethics. Oral and written informed consent was obtained in all cases prior procedure. Technique. EUS-guided puncture of the common bile duct was performed, followed by advancement of a guidewire to the intrahepatic bile ducts. After dilation of the fistulous tract with a cystotome, a fully covered self-expandable metal stent was inserted below the hepatic confluence and extending at least 3 cm in the duodenum. Technical and clinical success was achieved in four patients without adverse events. In one patient procedure failed due to dislocation of the guidewire, with consequent biliary leakage requiring urgent surgery. Recovery was uneventful with no further clinical sequelae and there was no mortality associated with procedure. Discussion. Introduced in 2001, EUS-guided biliary drainage has become an accepted option for treatment of obstructive jaundice. According to recent guidelines published by European Society of Gastrointestinal Endoscopy (ESGE) in 2022, EUS-CDS is a preferred modality to percutaneous transhepatic biliary drainage (PTBD) and surgery in patients with failed ERCP, with comparable efficiency and better safety profile, which is supported by our experience with the procedure. Conclusions. Our case series suggests that EUS-CDS is an excellent option for palliative management of malignant distal biliary obstruction, emphasizes on the importance of adequate technique and experience for the technical success, and urges the need for future research on establishing the best choice for guidewire and dilation device. Full article

Background. Stenting of patent ductus arteriosus (PDA) is a minimally invasive catheter-based temporary palliative procedure that is an alternative to a surgical shunt in neonates with duct-dependent pulmonary perfusion. Methods. An observational, single-centre, cross-sectional study of patients with duct-dependent pulmonary perfusion undergoing PDA-stenting as a stage I procedure and an analysis of short- to mid-term follow-up until a subsequent surgical procedure (stage II), with a focus on the interstage course. Results. Twenty-six patients were treated with PDA-stenting at a median (IQR) age of 7 (4–10) days; 10/26 patients (38.5%) (6/10 single pulmonary perfusion) were intended for later univentricular palliation, 16/26 patients (61.5%) (13/16 single pulmonary perfusion) for biventricular repair. PDA diameter was 2.7 (1.8–3.2) mm, stent diameter 3.5 (3.5–4.0) mm. Immediate procedural success was 88.5%. The procedure was aborted, switching to immediate surgery after stent embolisation, malposition or pulmonary coarctation in three patients (each n = 1). During mid-term follow-up, one patient needed an additional surgical shunt due to severe cyanosis, while five patients underwent successful catheter re-intervention 27 (17–30) days after PDA-stenting due to pulmonary hypo- (n = 4) or hyperperfusion (n = 1). Interstage mortality was 8.6% (2/23), both in-hospital and non-procedure-related. LPA grew significantly (p = 0.06) between PDA-stenting and last follow-up prior to subsequent surgical procedure (p = 0.06). RPA Z-scores remained similar (p = 0.22). The subsequent surgical procedure was performed at a median age of 106 (76.5–125) days. Conclusions. PDA-stenting is a feasible, safe treatment option, with the need for interdisciplinary decision-making beforehand and surgical backup afterwards. It allows adequate body and pulmonary vessel growth for subsequent surgical procedures. Factors determining the individual patient’s course should be identified in larger prospective studies. Full article

Magnesium (Mg) alloy has been used for medical vascular stents because of its good biocompatibility and degradability, but its rapid degradation and poor blood compatibility limits its further application. In this study, ferulic acid (FA) was conjugated onto the polydopamine (PDA) deposited Mg-Zn-Y-Nd alloy to prepare a PDA/FA multi-functional coating with better corrosion resistance and blood compatibility. The results suggest that the PDA/FA coating possessed potential application for surface modification of a medical Mg alloy. Full article

The transcatheter closure of patent ductus arteriosus (TCPC) has been demonstrated to be feasible even in infants weighing ≤1000 g. However, other percutaneous cardiac interventions (PCI) for such small infants born with congenital heart defects (CHD) or acquired heart defects (AHD) have not been well described. The purpose of this study was to describe the feasibility and safety of PCI in infants ≤1000 g. A retrospective review was conducted between June 2015 and May 2021, looking at 148 consecutive PCIs performed on infants weighing ≤1000 g at the time of the procedure. The procedural success rate was 100%. The major adverse event (AE) rate for TCPC was 3%, while there were no major AEs for other PCI. It is feasible to perform PCIs in infants weighing ≤1000 g with CHD and AHD using currently available technologies. Full article

Poly(L-lactic acid) (PLLA) has been used as a biodegradable vascular scaffold (BVS) material due to high mechanical property, biodegradability, and biocompatibility. However, acidic byproducts from hydrolysis of PLLA reduce the pH after the surrounding implanted area and cause inflammatory responses. As a result, severe inflammation, thrombosis, and in-stent restenosis can occur after implantation by using BVS. Additionally, polymers such as PLLA could not find on X-ray computed tomography (CT) because of low radiopacity. To this end, here, we fabricated PLLA films as the surface of BVS and divided PLLA films into two coating layers. At the first layer, PLLA film was coated by 2,3,5-triiodobenzoic acid (TIBA) and magnesium hydroxide (MH) with poly(D,L-lactic acid) (PDLLA) for radiopaque and neutralization of acidic environment, respectively. The second layer of coated PLLA films is composed of polydopamine (PDA) and then cystamine (Cys) for the generation of nitric oxide (NO) release, which is needed for suppression of smooth muscle cells (SMCs) and proliferation of endothelial cells (ECs). The characterization of the film surface was conducted via various analyses. Through the surface modification of PLLA films, they have multifunctional abilities to overcome problems of BVS effectively such as X-ray penetrability, inflammation, thrombosis, and neointimal hyperplasia. These results suggest that the modification of biodegradable PLLA using TIBA, MH, PDA, and Cys will have important potential in implant applications. Full article

It is generally accepted that stent implantation is the mainstream therapy in clinics for esophageal cancer in the later period. However, the restenosis caused by tumor cells, epithelial cells, and fibroblasts seriously interferes with the stent medical application and limits its long-term services. To address this conundrum, a series of drug-eluting stents were invented and verified to be feasible in the early stage after implantation, but the limited drug loading and good cell compatibility of the stent materials may lead to more serious restenosis and further endanger the patient’s life. In previous work, we modified the esophageal stent material 317L stainless steel (317L SS) surface with a poly-dopamine/poly-ethylenimine layer (PDA/PEI), which had strong anti-tumor functions. In this contribution, we employed a usual drug in clinic, 5-fluorouracil (5-Fu), with series of density onto the PDA/PEI modified 317L SS to investigate the influence of 5-Fu immobilization on the anti-restenosis function. The surface characterization including 5-Fu quantity, atomic force microscopy (AFM). Water contact angle measurement indicated successful preparation of the PDA/PEI/5-Fu layers. The spectrophotometric characterization revealed that the immobilized 5-Fu rapidly released over 24 h. However, the Eca109, Het-1A, and L929 cells culture results suggested that the released 5-Fu made a significant contribution to improving the apoptosis and necrosis of these pathological cells, and the PDA/PEI/5-Fu layers maintain the consistent anti-restenosis function on their surfaces with the PDA/PEI layer after 24 h. All the results demonstrated the PDA/PEI/5-Fu layers’ excellent ability to suppress esophageal tumor cells, epithelial cells, and fibroblasts, suggesting a potential application on the surface modification of esophageal stents for better anti-restenosis function. Full article