Local hyperthermia mediated by gold nanoparticle-integrated silicone-covered stent: feasibility and tissue response in a rat esophageal model.

BACKGROUND: To assess the feasibility and tissue response of using a gold nanoparticle (AuNP)-integrated silicone-covered self-expandable metal stent (SEMS) for local hyperthermia in a rat esophageal model. METHODS: The study involved 42 Sprague-Dawley rats. Initially, 6 animals were subjected to near-infrared (NIR) laser irradiation (power output from 0.2 to 2.4 W) to assess the in vitro heating characteristics of the AuNP-integrated SEMS immediately after its placement. The surface temperature of the stented esophagus was then measured using an infrared thermal camera before euthanizing the animals. Subsequently, the remaining 36 animals were randomly divided into 4 groups of 9 each. Groups A and B received AuNP-integrated SEMS, while groups C and D received conventional SEMS. On day 14, groups A and C underwent NIR laser irradiation at a power output of 1.6 W for 2 min. By days 15 (3 animals per group) or 28 (6 animals per group), all groups were euthanized for gross, histological, and immunohistochemical analysis. RESULTS: Under NIR laser irradiation, the surface temperature of the stented esophagus quickly increased to a steady-state level. The surface temperature of the stented esophagus increased proportionally with power outputs, being 47.3 ± 1.4 °C (mean ± standard deviation) at 1.6 W. Only group A attained full circumferential heating through all layers, from the epithelium to the muscularis propria, demonstrating marked apoptosis in these layers without noticeable necroptosis. CONCLUSIONS: Local hyperthermia using the AuNP-integrated silicone-covered SEMS was feasible and induced cell death through apoptosis in a rat esophageal model. RELEVANCE STATEMENT: A gold nanoparticle-integrated silicone-covered self-expanding metal stent has been developed to mediate local hyperthermia. This approach holds potential for irreversibly damaging cancer cells, improving the sensitivity of cancer cells to therapies, and triggering systemic anticancer immune responses. KEY POINTS: • A gold nanoparticle-integrated silicone-covered self-expanding metal stent was placed in the rat esophagus. • Upon near-infrared laser irradiation, this stent quickly increased the temperature of the stented esophagus. • Local hyperthermia using this stent was feasible and resulted in cell death through apoptosis.

Placement of a subcutaneous ureteral bypass in a Miniature Pinscher with presumed xanthine urolithiasis as a result of allopurinol treatment.

INTRODUCTION: This case report describes the long-term success of a subcutaneous ureteral bypass device in a dog for treatment of a ureteral obstruction. The suspected xanthine urolithiasis was secondary to treatment with allopurinol for leishmaniasis. The dog presented initially with lethargy, anuria and abdominal pain. Mild azotemia was found on biochemical analysis and abdominal ultrasound revealed bilateral ureteral obstruction. A subcutaneous ureteral bypass was subsequently placed using a standard surgical technique. The dog recovered uneventfully and the azotemia resolved within days. Follow-up examinations were performed every trimester for over three years and no complications like obstruction of the bypass tubes, urinary tract infection or azotemia were recognized during this follow-up period. Allopurinol was replaced with domperidone as long-term treatment against Leishmaniasis which resulted in a mild increase of the leishmania serum antibody titer. The subcutaneous ureteral bypass placement was successful and safe in this dog and is a valuable alternative in cases of ureteral obstruction also in dogs.

INTRODUCTION: Ce rapport de cas décrit le succès à long terme d'une dérivation urétérale sous-cutanée chez un chien pour le traitement d'une obstruction urétérale. L'urolithiase xanthique suspectée était secondaire à un traitement à l'allopurinol contre la leishmaniose. Le chien a d'abord présenté une léthargie, une anurie et des douleurs abdominales. L'analyse biochimique a révélé une légère azotémie et l'échographie abdominale a révélé une obstruction urétérale bilatérale. Une dérivation urétérale sous-cutanée a été mise en place selon une technique chirurgicale standard. Le chien s'est rétabli sans incident et l'azotémie a disparu en quelques jours. Des examens de suivi ont été effectués tous les trimestres pendant plus de trois ans et aucune complication telle qu'une obstruction du tube de dérivation, une infection urinaire ou une azotémie n'a été constatée au cours de cette période de suivi. L'allopurinol a été remplacé par de la dompéridone dans le cadre d'un traitement à long terme contre la leishmaniose, ce qui a entraîné une légère augmentation du titre des anticorps sériques contre la leishmaniose. La mise en place d'une dérivation urétérale sous-cutanée s'est avérée efficace et sûre chez ce chien et constitue une alternative intéressante en cas d'obstruction urétérale, y compris chez les chiens.

Evaluation of renovated double J stents using ureter models with and without stenosis.

PURPOSE: Commercial double J stents (DJS) have a uniform shape regardless of the specific nature of various ureteral diseases. We tested renovated DJS and compared them with conventional DJS using ureter models. METHODS: One straight ureter model included stenosis at the distal ureter near the ureterovesical junction and the other did not. We used conventional DJS and renovated 5- and 6-Fr soft DJS for ureter stones and 6-, 7-, and 8.5-Fr hard DJS for tumors. The DJS comprised holes in the upper, middle, or lower one-third of the shaft (length, 24 cm; 2-cm-diameter coils at both ends). More holes were created along the shaft based on the ureteral disease location. Conventional DJS had holes spaced 1 cm apart along the shaft. Renovated DJS had holes spaced 1 cm apart along the shaft with 0.5-cm intervals on the upper, middle, or lower one-third of the shaft. Urine flow was evaluated. RESULTS: As the DJS diameter increased, the flow rate decreased. The flow rates of DJS with holes in the lower shaft were relatively lower than those of conventional DJS and DJS with holes in the upper and middle shafts. In the ureter model without stenosis, 6-, 7-, and 8.5-Fr renovated stents exhibited significantly higher flow rates than conventional stents. In the ureter model with stenosis, 5-, 6-, 7-, and 8.5-Fr renovated stents did not exhibit significantly higher flow rates than conventional stents. CONCLUSION: Renovated stents and conventional stents did not exhibit significant differences in urine flow with stenosis.

In vivo evaluation of safety and performance of a tapered nitinol venous stent with inclined proximal end in an ovine iliac venous model.

A tapered stent with inclined proximal end is designed for fitting the iliac anatomically. The aim of the present study was to evaluate the safety and performance of the new stent in ovine left iliac veins. The experiment was performed in 30 adult sheep, and one nitinol-based VENA-BT® iliac venous stent (KYD stent) was implanted into each animal's left common iliac vein. Follow-up in all sheep consisted of angiographic, macroscopic, and microscopic examinations at Day 0 (< 24 h), Day 30, Day 90, Day 180 and Day 360 post-stenting (six animals per each time-point). 30 healthy ~ 50 kg sheep were included in this study and randomly divided into five groups according to the follow-up timepoint. All stents were implanted successfully into the left ovine common iliac vein. No significant migration occurred at follow-up. There is no statistically significant difference between the groups (p > 0.05), indicating no serious lumen loss occurred during the follow-up period. Common iliac venous pressure was further measured and the results further indicated the lumen patency at follow-up. Histological examinations indicated that no vessel injury and wall rupture, stent damage, and luminal thrombus occurred. There was moderate inflammatory cell infiltration around the stent in Day-0 and Day-30 groups with the average inflammation score of 2.278 and 2.167, respectively. The inflammatory reaction was significantly reduced in Day-90, Day-180 and Day-360 groups and the average inflammation scores were 0.9444 (p < 0.001, Day-90 vs Day-0), 1.167 (p < 0.001, Day-180 vs Day-0) and 0.667 (p < 0.001, Day-90 vs Day-0), respectively. The microscopic examinations found that the stents were well covered by endothelial cells in all follow-up time points. The results suggested that the KYD stent is feasible and safe in animal model. Future clinical studies may be required to further evaluate its safety and efficacy.

Prognostic Value of Poststenting Fractional Flow Reserve After Imaging-Guided Optimal Stenting.

BACKGROUND: Prognostic value of poststenting fractional flow reserve (FFR) remains uncertain in patients undergoing an imaging-guided optimal stenting strategy. OBJECTIVES: The authors evaluated the prognostic value of poststenting FFR according to the intracoronary imaging-guided lesion preparation, stent sizing, and postdilation (iPSP) strategy to optimize stent outcomes. METHODS: Poststenting FFR assessment was performed in 1,108 lesions in 1,005 patients from the IRIS-FFR registry. The primary outcome was target vessel failure (TVF), a composite of cardiac death, target vessel myocardial infarction, and target vessel revascularization at 5 years. RESULTS: At the index procedure, 326 lesions (29.4%) were treated using all 3 parts of the iPSP strategy. In the overall population, poststenting FFR was significantly associated with the risk of TVF at 5 years (per 0.01 increase of FFR, adjusted HR [aHR]: 0.94; 95% CI: 0.90-0.98; P = 0.004). Significant interaction was detected between poststenting FFR and the iPSP strategy on the risk of TVF at 5 years (P = 0.045 for interaction). In the iPSP group, poststenting FFR was not associated with the risk of TVF at 5 years (per 0.01 increase of FFR, aHR: 1.00; 95% CI: 0.96-1.05; P = 0.95), whereas a significant association between poststenting FFR and TVF at 5 years was observed in the no iPSP group (per 0.01 increase of FFR, aHR: 0.94; 95% CI: 0.90-0.99; P = 0.009). CONCLUSIONS: Poststenting FFR showed a significant association with cardiac events. However, its prognostic value appeared to be limited after the application of an imaging-guided optimal stenting strategy.

Migration of double-J ureteral stent in patients with ureteroileal anastomosis stricture undergoing radical cystectomy and orthotopic neobladder: Analysis risk factors of stent migration.

The objective was to evaluate the incidence and degree of double-J ureteral stent (DJUS) migration. Additionally, we aimed to investigate the risk factors associated with stent migration in the orthotopic neobladder group. In this retrospective study, 61 consecutive patients were included; 35 patients (45 DJUS placements) underwent radical cystectomy with orthotopic neobladder and 26 patients (35 DJUS placements) underwent urinary bladder without cystectomy between July 2021 and March 2023. All the patients were treated with a DJUS for ureteric strictures. The technical success rate was 100% in each group. The DJUS migration was significantly higher in the orthotopic neobladder group, with 22 of 45 cases (48.9%), compared to the urinary bladder group, which had 4 of 35 cases (11.4%) (P ≤ .001). Among the patients in the orthotopic neobladder group who experienced DJUS migration, stent dysfunction occurred in 18 cases (81.8%), which was statistically significant (P = .003). Multivariate logistic regression analysis revealed that only the size of the DJUS was significantly and positively associated with migration (odds ratio:10.214, P = .010). DJUS migration can easily occur in patients undergoing radical cystectomy and orthotopic neobladder, and smaller stent sizes are associated with a higher incidence of migration.

Endovascular treatment of wide-neck bifurcation aneurysms using pCONUS2 HPC bridging device with single antiplatelet: A Case Series.

RATIONALE: Wide neck bifurcation aneurysms (WNBA) are technically challenging for both surgical and endovascular treatments. Endovascular treatment for WNBA often requires dual antiplatelet therapy (DAPT) post stent insertion. Novel devices such as the pCONUS2 HPC neck bridging device have an HPC coating which reduces the device thrombogenicity. This theoretically allows for use of single antiplatelet therapy (SAPT), which would be advantageous, particularly in treating ruptured aneurysms. This case series aims to evaluate the safety of SAPT regimen only post stent insertion, by presenting our center early clinical experience in using pCONUS2 HPC neck bridging device in patients that are not suitable for DAPT. PATIENT CONCERNS: We report the cases of 3 patients (2 females, 1 male; range: 64-71 years old) who underwent coil embolization for WNBA using the pCONUS2 HPC device (2 unruptured WNBA, and 1 ruptured WNBA). As all 3 patients were allergic to Aspirin, they could only be started on SAPT post endovascular therapy. DIAGNOSIS: All 3 patients were diagnosed with WNBA on angiographic studies. Patient 1 had an unruptured left middle cerebral artery aneurysm; Patient 2 had a ruptured basilar tip aneurysm; Patient 3 had an unruptured anterior communicating artery (ACOM) aneurysm. INTERVENTIONS: All 3 WNBA were treated with pCONUS2 HPC neck bridging device. OUTCOMES: There were no immediate complications. The immediate angiographic result of aneurysm treatment in Patient 1 and Patient 2 demonstrated incomplete occlusions, with delayed complete occlusion of aneurysm in Patient 1 and growth of aneurysmal neck in Patient 2 on follow-up angiograms (range: 6-9 months). No major thrombo-embolic or hemorrhagic complications in the first 2 patients. For Patient 3, the immediate angiographic result of the treated aneurysm demonstrated complete occlusion. However, the patient readmitted 11 days post procedure with cerebral infarction, scoring 5 on the modified Rankin scale on discharge. LESSONS: pCONUS2 HPC as a neck bridging device in treating WNBA has yet to be shown superior to traditional techniques and devices. The theoretical advantage of HPC coating reducing its thrombogenicity requiring only SAPT is yet to be proven safe in clinical practice.

Late Migration of Fully Deployed Left Main Coronary Stent into Aortic Root: A Late Complication and Its Surgical Management.

ABSTRACT: Migration and embolization of a deployed stent is a rare complication of percutaneous coronary interventions (PCI) and can result in serious and potentially life-threatening complications. There are many reports of intracoronary stent entrapment, stripping, and dislodgement during PCI, however, only a few reports about migration. We report a rare case of migration of the left main coronary stent into the aortic root, which happened 5 months after the procedure and was treated by its partial removal through aortotomy along with surgical revascularization. The patient was discharged 5 days later, after an uneventful hospital stay.

Thirty-day outcomes of carotid endarterectomy versus carotid artery stenting in asymptomatic and symptomatic patients: a propensity score-matched analysis.

BACKGROUND: Technological and surgical approaches to carotid artery stenting (CAS) have evolved. Modern randomised controlled trials comparing CAS and carotid endarterectomy (CEA) are limited, and information about updated post-intervention outcomes are mostly from retrospective, small studies. AIMS: This study aims to compare the 30-day outcomes of stroke, transient ischaemic attack (TIA), acute myocardial infarction (AMI) and death with propensity-matched groups of CEA and CAS in asymptomatic and symptomatic patients over a recent study period of new CAS technologies and approaches. METHODS: A retrospective, observational, multicentre analysis was conducted including consecutive symptomatic and asymptomatic patients treated with either primary CEA or CAS for internal carotid artery stenosis, between 2015 and 2022. Patients were propensity score-matched based on comorbidities and assessed according to symptom status. Primary endpoints include composite ipsilateral stroke, TIA, AMI and death within 30 days. Secondary endpoints include technical success and length of hospital stay. RESULTS: From a cohort of 1,110 patients, propensity matching produced 269 distinct treatment pairs (n=538). Most patients were asymptomatic (n=456, 85%). All 6 strokes were minor (CEA=2; CAS=4) and registered among asymptomatic patients. One AMI (CEA) and 1 patient death (CAS) were reported among symptomatic patients. Composite stroke/AMI/death were not significantly different between both types of symptom status and both revascularisation techniques (p=0.44 and p=1, respectively). Technical success was 100%. The length of hospital stay was significantly shorter in asymptomatic patients treated with CAS compared to those treated with CEA (p=0.05), but no difference was registered among symptomatic patients (p=0.32). CONCLUSIONS: Propensity-matched analysis suggests that CAS has similar postprocedural outcomes for stroke, AMI and death at 30 days compared to CEA.

Preoperative pancreatic stent placement before the enucleation of insulinoma located in the head and neck of the pancreas in proximity to the main pancreatic duct: study protocol for a multicentre randomised clinical trial in Chinese tertiary medical centres.

INTRODUCTION: The surgical intervention approach to insulinomas in proximity to the main pancreatic duct remains controversial. Standard pancreatic resection is recommended by several guidelines; however, enucleation (EN) still attracts surgeons with less risk of late exocrine/endocrine insufficiency, despite a higher postoperative pancreatic fistula (POPF) rate. Recently, the efficacy and safety of preoperative pancreatic stent placement before the EN have been demonstrated. Thus, a multicentre open-label study is being conducted to evaluate the efficacy and safety of stent placement in improving the outcome of EN of insulinomas in proximity to the main pancreatic duct. METHODS AND ANALYSIS: This is a prospective, randomised, open-label, superiority clinical trial conducted at multiple tertiary centres in China. The major eligibility criterion is the presence of insulinoma located in the head and neck of the pancreas in proximity (≤2 mm) to the main pancreatic duct. Blocked randomisation will be performed to allocate patients into the stent EN group and the direct EN group. Patients in the stent EN group will go through stent placement by the endoscopist within 24 hours before the EN surgery, whereas other patients will receive EN surgery directly. The primary outcome is the assessment of the superiority of stent placement in reducing POPF rate measured by the International Study Group of Pancreatic Surgery standard. Both interventions will be performed in an inpatient setting and regular follow-up will be performed. The primary outcome (POPF rate) will be tested for superiority with the Χ2 test. The difference in secondary outcomes between the two groups will be analysed using appropriate tests. ETHICS AND DISSEMINATION: The study has been approved by the Peking Union Medical College Hospital Institutional Review Board (K23C0195), Ruijin Hospital Ethics Committee (2023-314), Peking University First Hospital Ethics Committee (2024033-001), Institutional Review Board of Xuanwu Hospital of Capital Medical University (2023223-002), Ethics Committee of the First Affiliated Hospital of Xi'an Jiaotong University (XJTU1AF2023LSK-473), Institutional Review Board of Tongji Medical College Tongji Hospital (TJ-IRB202402059), Ethics Committee of Tongji Medical College Union Hospital (2023-0929) and Shanghai Cancer Center Institutional Review Board (2309282-16). The results of the study will be published in an international peer-reviewed journal. TRIAL REGISTRATION NUMBER: NCT05523778.

Endovascular repair of an abdominal aortic aneurysm with external iliac artery occlusion using VBX as the contralateral leg via axillary delivery: A case report.

RATIONALE: A hostile iliac access route is an important consideration when enforcing endovascular aneurysm repair (EVAR) for abdominal aortic aneurysms (AAA). Herein, we report a case of AAA with unilateral external iliac artery occlusion, for which bifurcated EVAR was successfully performed using a single femoral and brachial artery access. PATIENT CONCERNS: A 76-year-old man who had undergone surgery for lung cancer 4.5 years prior was diagnosed AAA by computed tomography (CT). DIAGNOSIS: Two and a half years before presentation, CT revealed an infrarenal 48 mm AAA, which had enlarged to 57 mm by 2 months preoperatively. CT identified occlusion from the right external iliac artery to the right common femoral artery, with no observed ischemic symptoms in his right leg. The right external iliac artery, occluded and atrophied, had a 1 to 2 mm diameter. INTERVENTION: Surgery was commenced with the selection of a Zenith endovascular graft (Cook Medical) with an extended body length. Two Gore Viabahn VBX balloon expandable endoprosthesis (VBX; W.L. Gore & Associate) were delivered from the right axilla as the contralateral leg. OUTCOMES: CT scan on the 2nd day after surgery revealed no endoleaks. LESSONS: While the long-term results remain uncertain, this method may serve as an option for EVAR in patients with unilateral external iliac artery occlusion.