Endoscopic techniques for management of large colorectal polyps, strictures and leaks.

The implementation of screening colonoscopy with polyp removal has significantly decreased mortality rates associated with colorectal cancer (CRC), although it remains a major cause of cancer-related deaths globally. CRC typically originates from adenomatous polyps, and increased removal of these growths has led to reduced CRC incidence and mortality. Endoscopic polypectomy techniques, including hot and cold snare polypectomy, play a pivotal role in this process. While both methods are effective for small polyps (<10 mm), recent evidence favors cold snare polypectomy due to its superior safety profile and comparable complete resection rates. Large polyps (>10 mm), particularly those with advanced features, pose increased cancer risks and often require meticulous assessment and advanced endoscopic techniques, including endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD), for resection. This chapter also provides a practical overview of endoscopic techniques for managing colonic obstructions and pericolonic fluid collections, detailing their indications, advantages, disadvantages, and complications. The goal is to improve understanding and application in clinical practice. Additionally, we provide a summary of endoscopic closure techniques that have revolutionized the management of perforations and fistulas, offering safe and effective alternatives to surgery.

Drug-Coated Balloon Angioplasty in Patients Undergoing Complex Percutaneous Coronary Intervention.

Background: There are limited clinical data on drug-coated balloon (DCB)-based percutaneous coronary intervention (PCI) compared with drug-eluting stent (DES)-only PCI in patients with complex coronary artery lesions. Objectives: The goal of the current study was to investigate the efficacy of DCB in patients undergoing PCI for complex coronary artery lesions. Methods: From an institutional registry of patients with de novo complex coronary artery lesions, 126 patients treated with DCB-based PCI were compared with 234 propensity score-matched patients treated with DES-only PCI. Complex coronary artery lesions were defined as the presence of at least 1 of the following: bifurcation, chronic total occlusion, unprotected left main disease, long lesion ≥38 mm, multivessel disease, lesion requiring ≥3 devices, or severe calcification. The primary endpoint was target vessel failure (TVF) at 2 years, a composite of cardiac death, target vessel-related myocardial infarction, and target vessel revascularization. Results: Baseline characteristics were comparable between the 2 groups. DCB-based PCI showed a comparable risk of TVF vs DES-based PCI (7.6% vs 8.1%; HR: 0.81; 95% CI: 0.33-1.99; P = 0.638). The risks of cardiac death (5.0% vs 5.7%; HR: 0.78; 95% CI: 0.24-2.49), target vessel-related myocardial infarction (0.9% vs 1.3%; HR: 2.65; 95% CI: 0.26-27.06), and target vessel revascularization (3.5% vs 2.0%; HR: 1.30; 95% CI: 0.30-5.67) were also comparable between the 2 groups. Conclusions: DCB-based PCI showed comparable risks of TVF vs those of DES-only PCI in patients with complex coronary artery lesions. DCB might be considered as a suitable alternative device to DES in patients undergoing complex PCI. (Long-term Outcomes and Prognostic Factors in Patient Undergoing CABG or PCI; NCT03870815).

Oxygen-generating biomaterials for cardiovascular engineering: unveiling future discoveries.

Oxygen-generating biomaterials are emerging as a groundbreaking solution for transforming cardiovascular engineering. These biomaterials generate and release oxygen within various biomedical applications, marking a new frontier in healthcare. Most cardiovascular treatments face a significant challenge, ensuring a consistent oxygen supply to nurture engineered tissues or even implanted devices. Traditional methods relying on passive oxygen diffusion often fall short, hindering functional cardiovascular tissue development. Oxygen-generating biomaterials, incorporating agents like calcium peroxide, provide a controlled oxygen source to the surrounding cells. This innovation potentially enhances cell viability, stimulates growth and boosts metabolic activity crucial for tissue health. Applications include repairing cardiac and vascular tissues, disease modeling, drug testing and personalized medicine, promising tailored treatments. Challenges like material toxicity and oxygen release control need consideration. As research progresses, the use of these innovative biomaterials in clinical translation could reshape cardiovascular healthcare, revolutionizing patient outcomes in heart disease treatment.

The effects of fibroblast growth factor-23 on diagnosis of cerebral infarction and vertebral basilar artery stenosis☆.

OBJECTIVES: This study aimed to explore the correlation between Fibroblast Growth Factor-23 (FGF23) levels and Cerebral Infarction (CI), and to determine whether there is a significant relationship between FGF23 and the occurrence and severity of CI. METHODS: The study categorized Cerebral Infarction (CI) patients into severe and mild stenosis groups based on vertebrobasilar artery stenosis, using Digital Subtraction Angiography (DSA) and Magnetic Resonance Imaging (MRI). The study compared the levels of Fibroblast Growth Factor-23 (FGF23) in the serum of CI patients and healthy controls using a t-test and evaluated the diagnostic effectiveness of serum FGF23 using a Receiver Operating Characteristic (ROC) curve. Additionally, the study analyzed the correlation between FGF23 levels and CI severity after treatment using the National Institute of Health Stroke Scale score. RESULTS: The study found a significant increase in serum Fibroblast Growth Factor-23 (FGF23) levels in patients with Cerebral Infarction (CI) compared to healthy volunteers, (p < 0.001). A higher serum FGF23 level was observed in the severe stenosis group than in the mild stenosis group (p < 0.001). Furthermore, the study showed that a high FGF23 level at admission was significantly related to more severe symptoms of CI as indicated by the National Institute of Health Stroke Scale (NIHSS) score on the 7th day after treatment (p < 0.001). CONCLUSIONS: This study discovered a correlation between Fibroblast Growth Factor-23 (FGF23) levels, vertebrobasilar artery stenosis, and short-term prognosis in patients who had recently experienced acute Cerebral Infarction (CI).

Colonic stenting: is the bridge to surgery worth its cost? A cost-effectiveness analysis at a single Asian institution.

Purpose: In patients with acute left-sided colonic obstruction, stenting can convert an emergency operation into a semi-elective procedure. However, its use continues to be debated. We performed a cost-effective analysis using our institution's experiences. Methods: Endoscopic, surgical, and financial details were prospectively collected for patients who presented with acute colonic obstruction and underwent stenting between 2019 and 2022. Outcomes were defined as technical/clinical success and successful surgical resection. The financial cost of stenting was compared with the expected cost without stenting. Results: Forty patients were included, with 29 undergoing definitive resection. The most common pathology was primary colon cancer (27 patients, 93%). Endoscopic stenting had high technical (90%) and clinical (83%) success rates, with low rates of complications such as perforation (2 patients, 7%) and migration (0 patients, 0%). As a bridge to surgery, the median procedure time was 226 minutes and the surgical outcomes also showed a low rate of complications (3 patients, 11%), such as anastomotic leakage (0 patients, 0%), intraabdominal abscesses (2 patients, 7%), and 30-day postoperative mortality (0 patients, 0%). The cumulative costs with colonic stenting were $32,900, while the expected costs with emergency surgery, including stoma reversal, were $40,700 (healthcare cost-savings of $7,800 per person). The difference was mainly due to the avoidance of upfront emergency surgery. The incremental cost-effectiveness ratio was 0.81, favoring colonic stenting over upfront emergency surgery. Conclusion: Colonic stenting as a bridge to surgery is safe and cost-effective for treating left-sided colonic obstruction with high success rates and low complication rates.

One-Month Dual Antiplatelet Therapy in High Bleeding Risk Asian Patients Undergoing Percutaneous Coronary Intervention　- Onyx ONE Clear 2-Year Results.

Background: One-month dual antiplatelet therapy (DAPT) in high bleeding risk (HBR) patients undergoing percutaneous coronary intervention (PCI) with the Resolute OnyxTM zotarolimus-eluting stents (ZES) is safe and effective. Asian patients have a unique ischemia/bleeding risk profile. Here, we compare the outcomes between Asian and non-Asian patients after PCI and 1-month DAPT. Methods and Results: Onyx ONE Clear was a prospective, multicenter study enrolling HBR patients undergoing PCI with the Resolute Onyx ZES (ClinicalTrials.gov identifier NCT03647475). Event-free patients after 1-month DAPT transitioned to single antiplatelet therapy. Clinical outcomes between 1 month and 2 years were compared between patients from Asian and non-Asian countries after 1 : 1 propensity score matching accounting for baseline differences. Patients from Asian countries represented 18% (n=273) of the study group (n=1,507). Non-Asian patients had greater clinical complexity; however, these differences were minimal after matching. There were no significant differences in ischemic outcomes between matched cohorts from 1 month to 2 years, including the primary composite endpoint of cardiac death or myocardial infarction (12% vs. 12%; P>0.99). However, there were significantly fewer Bleeding Academic Research Consortium types 3-5 bleeding events in the Asian vs. non-Asian cohort (4% vs. 9%; P=0.007), despite similar bleeding risk profiles after matching. Conclusions: After propensity score matching, HBR patients from Asian countries undergoing PCI treated with 1-month DAPT had similar ischemic outcomes but fewer bleeding events between 1 month and 2 years compared with patients from non-Asian countries.

Coronary Bioresorbable metallic stents:Advancements and future perspectives.

Percutaneous coronary intervention is a critical treatment for coronary artery disease, particularly myocardial infarction, and is highly recommended in clinical guidelines. Traditional metallic stents, although initially effective, remain permanently in the artery and can lead to complications such as in-stent restenosis, late thrombosis, and chronic inflammation. Given the temporary need for stenting and the potential for late complications, bioresorbable stents have emerged as a promising alternative. However, bioresorbable polymeric stents have encountered significant clinical challenges due to their low mechanical strength and ductility, which increase the risks of thrombosis and local inflammation. Consequently, bioresorbable metals are being considered as a superior option for coronary stents. This review examines the progress of bioresorbable metallic stents from both preclinical and clinical perspectives, aiming to provide a theoretical foundation for future research. Iron, zinc, and magnesium are the primary materials used for these stents. Zinc-based bioresorbable stents have shown promise in preclinical studies due to their biocompatibility and vascular protective properties, although human clinical studies are still limited. Magnesium-based stents have demonstrated positive clinical outcomes, being fully absorbed within 12 months and showing low rates of late lumen loss and target lesion failure at 6- and 12-months post-implantation. Initial trials of iron-based stents have indicated favorable mid-term safety and efficacy, with complete absorption by the body within three years and consistent luminal expansion beyond six months post-implantation. Despite these advancements, further trials are needed for comprehensive validation. In conclusion, while current materials do not fully meet the ideal requirements, ongoing research should focus on developing bioresorbable stents with enhanced performance characteristics to better meet clinical needs.

Serial Vascular Responses of Balloon-Expandable Stent With Biodegradable Film-Type Graft in a Rabbit Iliac Artery Dissection Model (BioGard Study).

BACKGROUND AND OBJECTIVES: Arterial dissection during endovascular therapy rarely occurs but can be lethal. A fabric-based covered graft stents yield poor clinical outcomes. A novel balloon-expandable stent with biodegradable film graft for overcoming these issues was evaluated in a rabbit iliac artery model. METHOD: Eighteen rabbits with iliac artery dissections were induced by balloon over-inflation on angiography (Ellis type 2 or 3) and treated using the test device (3.0×24 mm). Subsequently, survived twelve animals underwent histologic examinations and micro-computed tomography (CT) at 0, 2, 4, and 8 weeks and 3, 6, 9, and 12 months and angiography at one-year. RESULTS: There were no adverse cardiovascular events during the one-year. Early-stage histologic examination revealed complete sealing of disrupted vessels by the device, exhibiting mural hematoma, peri-stent red thrombi, and dense infiltration of inflammatory cells. Mid- and long-term histologic examination showed patent stents with neointimal hyperplasia over the stents (% area stenosis: 11.8 at 2 weeks, 26.1 at 1 month, 29.7 at 3 months, 49.2 at 9 months, and 51.0 at 1 year), along with mild peri-strut inflammatory response (Grade: 1-2 at mid-term and 0-1 at long-term). The graft film became scarcely visible after six months. Both CT and angiography revealed no instances of thrombotic occlusion or in-stent restenosis (% diameter stenosis: 5.7 at 2 weeks, 12.3 at 1 month, 14.2 at 3 months, 25.1 at 9 months, and 26.6 at 1 year). CONCLUSIONS: The novel balloon-expandable stent with a biodegradable film graft demonstrates feasibility in managing severe artery dissection and preventing lethal vascular events in animal model.

Myocardial ischemia caused by the synergistic effect of myocardial bridge and moderate stenosis: case report.

BACKGROUND: Clinical events such as angina pectoris, acute coronary syndrome, and sudden death caused by myocardial bridge (MB) have attracted increasing attention. It is still a challenge to diagnose whether MB can cause the symptoms of patients with MB. For most MB patients, medication remains the primary treatment. CASE PRESENTATION: This article reports a case of chest pain in a patient with MB in the middle segment of the left anterior descending artery (LADm) with moderate stenosis in the proximal segment (LADp). Through functional assessment, we found that neither MB nor fixed stenosis had sufficient effect on coronary blood flow to cause myocardial ischemia, but their synergistic effect resulted in myocardial ischemia. Finally, a stent was implanted in LADp and good clinical results were achieved. CONCLUSIONS: For symptomatic patients with MB combined with fixed stenosis, functional evaluation may be necessary, which has significant guiding significance for treatment strategy selection. For asymptomatic patients, early detection of myocardial ischemia may also improve the prognosis of patients.

Pathological Evaluation of Predictors for Delayed Endothelial Coverage After Currently Available Drug-eluting Stent Implantation in Coronary Arteries: Impact of Lesions With Acute and Chronic Coronary Syndromes.

BACKGROUND: The optimal duration of dual antiplatelet therapy after currently available drug-eluting stent (DES) implantation to prevent stent thrombosis (ST) remains controversial. Delayed healing is frequently identified as a leading cause of ST in the early phase. However, a thorough pathological investigation into strut coverage after currently available DES implantation is lacking-a gap addressed in the current study. METHODS: From our autopsy registry of 199 stented lesions, 4,713 struts from 66 currently available DES-stented lesions with an implant duration ≤370 days were histologically evaluated. Endothelial coverage was defined as the presence of luminal endothelial cells overlying struts and an underlying smooth muscle cell layer. The stented lesions were classified into acute coronary syndrome (ACS) (n = 40) and chronic coronary syndrome (CCS) (n = 26) groups and were compared. Endothelial coverage predictors were identified through logistic analysis. RESULTS: Although ACS and CCS lesions presented comparable clinical characteristics, including age, sex, and cause of death, the latter exhibited a significantly higher prevalence of chronic kidney disease and hemodialysis than the former (33.3% vs. 65.2%; p = 0.02, 7.7% vs. 30.4%; p = 0.02). The poststent implant median duration was significantly shorter in ACS lesions than in CCS lesions (13 [IQR 5-26 days] vs. 40 [IQR 16-233 days]; p < 0.01). The endothelial coverage percentage was 3.5% at 30 days and 27.7% at 90 days after currently available DES implantation. Multivariable logistic regression analysis implicated implant duration of ≤90 days [odds ratio (OR), 0.009; 95% confidence interval (CI), 0.006-0.012; p < 0.01], superficial calcification (OR, 0.11; 95% CI, 0.07-0.17; p < 0.01), ACS culprit site (OR, 0.29; 95% CI, 0.09-0.94; p = 0.039), and circumferentially durable polymer-coated DES (OR, 0.32; 95% CI, 0.24-0.41; p < 0.01) as delayed endothelial coverage predictors. CONCLUSIONS: Endothelial coverage was limited at 90 days after currently available DES implantation, and the ACS culprit site and circumferentially durable polymer-coated DES were identified as independent predictors of delayed endothelial coverage. Our findings suggest the importance of underlying plaque morphology and stent technology for vessel healing after such implantation.

[Clinical outcomes of percutaneous intervention on the unprotected left main coronary artery]. / Desenlaces clínicos de la intervención percutánea sobre tronco coronario izquierdo no protegido.

Background: The debate on percutaneous coronary intervention (PCI) of the unprotected left main coronary artery (LMCA) has been constant over time. Objective: To investigate the clinical and procedural characteristics and cardiovascular outcomes of PCI of unprotected LMCA. Material and methods: Observational study which included patients with unprotected LMCA disease undergoing PCI; patients with cardiogenic shock prior to the procedure were excluded. We describe the clinical and angiographic characteristics, as well as the major adverse cardiac and cerebrovascular events (MACCE) according to the year of the procedure. Results: We included 73 patients, with a SYNTAX I score of 31.2 ± 9.1, mostly with ST-elevation acute coronary syndrome (35%). There was a higher frequency of triple vessel coronary disease (63%) and distal LMCA lesions (35%). The provisional stent technique was the most used for distal lesions (58%) and the 2-stent technique for bifurcation lesions (78%), supported by intravascular ultrasound (IVUS) in 38%. During follow-up, 19 presented MACCE (26%), out of which cardiac death occurred in 13%, non-cardiovascular death in 5%, non-fatal acute myocardial infarction in 1%, cerebrovascular event in 2%, and revascularization of the treated vessel in 4%. Conclusions: It was observed a similar frequency to the one appearing in other studies of cardiovascular events, mainly in patients with intermediate risk, which supports the increasing use of percutaneous intervention in this population.

Introducción: el debate sobre la intervención coronaria percutánea (ICP) del tronco coronario izquierdo (TCI) no protegido ha sido constante a lo largo del tiempo. Objetivo: investigar las características clínicas, de procedimiento y los desenlaces cardiovasculares de la ICP del TCI no protegido. Material y métodos: estudio observacional que incluyó pacientes con enfermedad del TCI no protegido sometidos a ICP; se excluyeron pacientes con choque cardiogénico previo al procedimiento. Describimos las características clínicas y angiográficas, así como los eventos adversos cardiovasculares y cerebrales mayores (MACCE) según el año del procedimiento. Resultados: incluimos 73 pacientes, con puntuación de SYNTAX I de 31.2 ± 9.1, mayormente con síndrome coronario agudo con elevación del ST (35%). Hubo mayor frecuencia de enfermedad coronaria trivascular (63%) y lesión distal del TCI (35%). La técnica de stent provisional fue la más usada para lesiones distales (58%) y la técnica de 2 stents para las lesiones en bifurcación (78%), con apoyo del ultrasonido intravascular (IVUS) en el 38%. En el seguimiento se presentaron 19 MACCE (26%), de los cuales la muerte de causa cardiaca se presentó en el 13%, muerte no cardiovascular en 5%, infarto agudo al miocardio no fatal en 1%, evento vascular cerebral en 2% y nueva revascularización del vaso tratado en 4%. Conclusiones: se observó una frecuencia similar a la de otros estudios de eventos cardiovasculares, especialmente en pacientes con riesgo intermedio, lo cual apoya el uso creciente de la intervención percutánea en esta población.

The Mechanical and Electrochemical Stability of Trimethysilane Plasma Nanocoatings Deposited onto Cobalt Chromium Cardiovascular Stents.

The objective of this study was to evaluate the coating integrity performance and corrosion protection property of trimethylsilane (TMS) plasma nanocoatings that were directly deposited onto cobalt chromium (CoCr) L605 cardiovascular stents. Hydrophilic surfaces were achieved for the TMS plasma nanocoatings that were deposited onto the coronary stents through NH3/O2 (2:1 molar ratio) plasma post-treatment. With a coating thickness of approximately 20-25 nm, the TMS plasma nanocoatings were highly durable and able to resist delamination and cracking from crimping and expansion by a Model CX with a J-Crimp Station. The stent surface that was evaluated by Scanning Electron Microscopy (SEM) and Energy-Dispersive X-ray Spectroscopy (EDS) showed no indications of pitting, corrosion, or adsorption products on either the luminal or abluminal surfaces of the stents, in contrast to the uncoated stent surface. The TMS plasma nanocoatings significantly enhanced the stent's corrosion resistance in immersion experiments that followed the ASTM F2129-15 corrosion protocol, evident in the increase of the open circuit potential (OCP) from 0.01 V for the uncoated L605 stent to 0.18 V for the plasma-nanocoated L605 stent, reducing potential cytotoxic metal ion release. Cyclic polarization (CP) curves show that the corrosion rate (density level) observed in plasma-nanocoated L605 stents was approximately half an order of magnitude lower than that of the uncoated stents, indicating improved corrosion protection of the stents. CP curves of the TMS plasma-nanocoated stents with different coating thicknesses show that, in the range of 20-65 nm, the coating thickness does not result in any difference in the corrosion resistance of the stents.

Rescue Stenting of Isolated Middle Cerebral Artery (MCA) Dissections (MCAD) with Antithrombogenic Coated Stents and Mono-Antiplatelet Therapy (MAPT).

Objective: Acute ischemic stroke (AIS) is a leading cause of death, but isolated middle cerebral artery dissection (MCAD) is rarely reported. The aim of this article is to sum up the current information on this pathology and to explore the technical aspects of its endovascular treatment with emphasis on novel coated, antithrombogenic stents and antiplatelet management. Another part of this article offers our experience with the problematics represented by a small sample group of patients with an MCAD diagnosis who were treated in our center. Methods: We conducted literature research and a retrospective review of patients treated for anterior circulation AIS at our comprehensive stroke center from January 2022 to March 2024. The cohort included 16 patients diagnosed with isolated MCAD, 9 received antithrombogenic coated stents, while 7 received bare metal stents. Pharmacological management of coated stents involved the use of Cangrelor for acute antiplatelet therapy, transitioning to oral Ticagrelor. Results: Among the 16 patients treated, those with antithrombogenic coated stents showed no major complications and had a lower incidence of intracranial hemorrhage compared to the bare metal stent group. The average National Institutes of Health Stroke Scale (NIHSS) score at discharge improved in both groups. Functional outcomes and mortality rates were slightly better in the coated stent group, but no statistical significance was proven. Conclusions: Antithrombogenic coated stents, in conjunction with MAPT, demonstrated a safe and effective option for treating isolated MCAD. These stents offer promising potential for improved outcomes and reduced complications compared to traditional treatments. Further multicentric studies with larger cohorts are recommended to validate these findings.

Management of cephalic arch stenosis in hemodialysis access: Updated systematic review and meta-analysis.

INTRODUCTION: Cephalic arch stenosis (CAS) is often recurrent, resistant to treatment and the intervention outcome is not well validated so far. We purposed to assess the clinical outcomes of CAS treatment in patients with hemodialysis access. METHODS: Electronic bibliographic sources were searched up to December 4 2023 to identify studies reported outcome after treating CAS. Direct and indirect evidence was combined to compare odds ratios (OR) and surfaces under the cumulative ranking curves across the different treatment modalities through meta-analysis and network meta-analyses (NMA). This systematic review was conducted in accordance with the PRISMA-P. The review is registered in PROSPERO (CRD42022296513). RESULTS: Four randomized controlled trials (RCTs) and 15 non-RCTs were included in the analysis. The study population differed in fistula type, restenosis or thrombosis, and significant heterogeneity was observed among the publications. The risk of bias was low to serious. Meta-analysis found no significant difference between DCB and PTA in primary patency at 6 and 12 months (OR 1.16 and 0.60, respectively; low certainty of evidence). Favorable result with STG compared to stent or PTA at 3, 6, and 12 month was observed (OR 4.28, 5.13, and 13.12, and 4.28, 5.13, 13.12, respectively; low certainty of evidence). Regarding primary patency, the treatment rankings, from highest to lowest, were STG (92.7%), transposition (76.0%), stent (67.5%), DCB (46.3%), and PTA (64.5%) at 12 months. CONCLUSION: Despite data limitations, the low-quality evidence suggests that STG may merit consideration as a primary treatment option when all alternatives are applicable, given their potential for better primary patency and higher treatment ranking.

Ultrasound-guided nitinol stent implantation to treat early restenosis of arteriovenous fistula: A 69-case study with 1-year outcome.

BACKGROUND: To investigate the feasibility, methods and effects of interventional ultrasound in nitinol stent implantation to treat early restenosis after percutaneous transluminal angioplasty (PTA) in autogenous arteriovenous fistula (AVF). METHODS: From April 2018 to December 2021, 69 patients with early restenosis of AVF received ultrasound-guided nitinol stent implantation (UNSI) and were followed-up. Imaging features of the stent and procedure by ultrasound were observed. The technical success rate, clinical success rate and incidence of complications were recorded and counted. Target lesion primary patency (TLPP), access circuit primary patency (ACPP) and access circuit secondary patency (ACSP) were estimated. RESULTS: Ultrasonography can show the structure of the stent and guide the stenting process clearly. Both the technical and clinical success rates were 100%. Thirty-one patients had in-stent restenosis (ISR), which was treated by plain balloon (PB) PTA or drug coated balloon (DCB) PTA. The TLPP at 3, 6, 12 and 24 months were 100.0%, 94.2%, 63.4% and 39.6%, respectively. The ACPP at 3, 6, 12 and 24 months were 98.6%, 91.6%, 60.2% and 35.2%, respectively. The ACSP at 3, 6, 12 and 24 months were 98.6%, 98.6%, 95.6% and 93.8%, respectively. The TLPP of ISR after DCB PTA at 3, 6 and 12 months were 100.0%, 100.0% and 93.6%, respectively. CONCLUSIONS: This pilot study indicates ultrasonography can accurately guide nitinol stent implantation in AVF and this technique is a feasible and minimally invasive treatment for early restenosis after PTA with good short- and medium-term patency. DCB PTA may be used to deal with the ISR and is a way to prolong the patency of nitinol stent.

Safety and efficacy of Kaffes intraductal self-expanding metal stents in the management of post-liver transplant anastomotic strictures.

BACKGROUND: Endoscopic management is the first-line therapy for post-liver-transplant anastomotic strictures. Although the optimal duration of treatment with plastic stents has been reported to be 8-12 months, data on safety and duration for metal stents in this setting is scarce. Due to limited access to endoscopic retrograde cholangiopancreatography (ERCP) during the coronavirus disease 2019 pandemic in our centre, there was a change in practice towards increased usage and length-of-stay of the Kaffes biliary intraductal self-expanding stent in patients with suitable anatomy. This was mainly due to the theoretical benefit of Kaffes stents allowing for longer indwelling periods compared to the traditional plastic stents. AIM: To compare the safety and efficacy profile of different stenting durations using Kaffes stents. METHODS: Adult liver transplant recipients aged 18 years and above who underwent ERCP were retrospectively identified during a 10-year period through a database query. Unplanned admissions post-Kaffes stent insertion were identified manually through electronic and scanned medical records. The main outcome was the incidence of complications when stents were left indwelling for 3 months vs 6 months. Stent efficacy was calculated via rates of stricture recurrence between patients that had stenting courses for ≤ 120 d or > 120 d. RESULTS: During the study period, a total of 66 ERCPs with Kaffes insertion were performed in 54 patients throughout their stenting course. In 33 ERCPs, the stent was removed or exchanged on a 3-month interval. No pancreatitis, perforations or deaths occurred. Minor post-ERCP complications were similar between the 3-month (abdominal pain and intraductal migration) and 6-month (abdominal pain, septic shower and embedded stent) groups - 6.1% vs 9.1% respectively, P = 0.40. All strictures resolved at the end of the stenting course, but the stenting course was variable from 3 to 22 months. The recurrence rate for stenting courses lasting for up to 120 d was 71.4% and 21.4% for stenting courses of 121 d or over (P = 0.03). There were 28 patients that were treated with a single ERCP with Kaffes, 21 with removal after 120 d and 7 within 120 d. There was a significant improvement in stricture recurrence when the Kaffes was removed after 120 d when a single ERCP was used for the entire stenting course (71.0% vs 10.0%, P = 0.01). CONCLUSION: Utilising a single Kaffes intraductal fully-covered metal stent for at least 4 months is safe and efficacious for the management of post-transplant anastomotic strictures.

Efficacy of different stent types in post-liver-transplant anastomotic biliary strictures: a systematic review and meta-analysis.

Background: Stent selection in the endoscopic management of post-liver-transplant anastomotic biliary strictures remains controversial. This systematic review and meta-analysis aimed to evaluate the potential differences between available stents. Methods: MEDLINE, Cochrane, and Scopus databases were searched until April 2023 for comparative studies evaluating stricture management using multiple plastic stents (MPS) and self-expandable metal stents (SEMS), including fully-covered (FC)- and intraductal (ID)-SEMS. The primary outcome was stricture resolution, while secondary outcomes included stricture recurrence, stent migration and adverse events. Meta-analyses were based on a random-effects model and the results were reported as odds ratios (OR) with 95% confidence intervals (CI). Subgroup analyses by type of metal stent and a cost-effectiveness analysis were also performed. Results: Nine studies (687 patients) were finally included. Considering stricture resolution, SEMS and MPS did not differ significantly (OR 0.99, 95%CI 0.48-2.01; I 2=35%). Stricture recurrence, migration rates and adverse events were also comparable (OR 1.71, 95%CI 0.87-3.38; I 2=55%, OR 0.73, 95%CI 0.32-1.68; I 2=56%, and OR 1.47, 95%CI 0.89-2.43; I 2=24%, respectively). In the subgroup analysis, stricture resolution and recurrence rates did not differ for ID-SEMS vs. MPS or FC-SEMS vs. MPS. Migration rates were lower for ID-SEMS compared to MPS (OR 0.28, 95%CI 0.11-0.70; I 2=0%), and complication rates were higher after FC-SEMS compared to MPS (OR 1.76, 95%CI 1.06-2.93; I 2=0%). Finally, ID-SEMS were the most cost-effective approach, with the lowest incremental cost-effectiveness ratio: 3447.6 £/QALY. Conclusion: Stent type did not affect stricture resolution and recurrence; however, ID-SEMS placement was the most cost-effective approach compared to the alternatives.

Dosimetric characteristics of self-expandable metallic and plastic stents for transpapillary biliary decompression in external beam radiotherapy.

There is little evidence regarding radiation dose perturbation caused by the self-expandable metallic stents (SEMSs) used for transpapillary biliary decompression. We aimed to compare SEMSs with plastic stents (PSs) and clarify their dosimetric characteristics. Fifteen SEMSs (10 braided and 5 lasercut type) and six PSs (diameter: 2.3-3.3 mm) were inserted into a water-equivalent solid phantom. In total, 13 SEMSs had radiopaque markers, whereas the other two did not. Using radiochromic films, the dose difference adjacent to the stents at locations proximal, distal, and arc delivery to the radiation source was evaluated based on comparison to measurement of the dose delivery in phantom without any stent in place. The median values of the dose difference for each stent were used to compare the SEMS and PS groups.Results: The dose difference (median (minimum/maximum)) was as follows: proximal, SEMSs + 2.1% (1.8 / 4.7) / PSs + 5.4% (4.1 / 6.3) (p < 0.001); distal, SEMSs -1.0% (-1.6 /-0.4) / PSs -8.9% (-11.7 / -7.4) (p < 0.001); arc delivery, SEMSs 1.2% (0.9 / 2.3) / PSs 2.2% (1.6 / 3.6) (p = 0.005). These results demonstrated that the dose differences of SEMSs were significantly smaller than those of PSs. On the other hand, the dose difference was large at surface of the radiopaque markers for SEMSs: proximal, 10.3% (7.2 / 20.9); distal, -8.4% (-16.3 / -4.2); arc delivery, 5.5% (4.2 / 9.2). SEMSs for biliary decompression can be safely used in patients undergoing radiotherapy, by focusing on the dose distribution around the stents and by paying attention to local changes in the dose distribution of radiopaque markers.

Advances in self-expandable metal stents for endoscopic ultrasound-guided interventions.

Endoscopic ultrasound (EUS)-guided interventions have evolved rapidly in recent years, with dedicated metal stents playing a crucial role in this process. Specifically, the invention of biflanged short metal-covered stents, including lumen-apposing metal stents (LAMS), and modifications in a variety of tubular self-expandable metal stents (SEMS), have led to innovations in EUS-guided interventions. LAMS or non-LAMS stents are commonly used in the EUS-guided drainage of pancreatic fluid collections, especially in cases of walled-off necrosis. Additionally, LAMS is commonly considered for drainage of the EUS-guided gallbladder or dilated common bile duct and EUS-guided gastroenterostomy. Fully or partially covered tubular SEMS with several new designs are being considered for EUS-guided biliary drainage. This review focuses on advances in SEMS for EUS-guided interventions and discusses related research results.