Report of a semi-branched stent-graft to treat a type 1a endoleak after failed EVAR.

BACKGROUND: Endovascular techniques are advancing with the change of treatment paradigm for abdominal aortic aneurysms. Fenestrated EVAR (fEVAR) and branched EVAR (bEVAR) are used for complex aortic aneurysm repair. Both fEVAR and bEVAR have their own advantages and disadvantages. Semi-branches are a new feature that attempt to combine the advantages of both fEVAR and bEVAR. TECHNIQUE: We describe the use of a 4-vessel semi-branched EVAR in a failed EVAR case with a type 1a endoleak. CONCLUSION: The novel feature of semi-branches in custom-made EVAR devices in endovascular aortic treatment following failed EVAR appear to be a feasible option.

Insight into the fracture energy dissipation mechanism in elastomer composites via sacrificial bonds and fillers.

Most tough elastomer composites are reinforced by introducing sacrificial structures and fillers. Understanding the contribution of fillers and sacrificial bonds in elastomer composites to the energy dissipation is critical for the design of high-toughness materials. However, the energy dissipation mechanism in elastomer composites remains elusive. In this study, using a tearing test and time-temperature superposition, we investigate the effect of fillers and sacrificial bonds on the energy dissipation of elastomer composites consisting of poly(lipoic acid)/silver-coated Al fillers. We found that the fillers and sacrificial bonds mutually enhance both the intrinsic fracture energy and the bulk energy dissipation, and moreover the sacrificial bonds play a more important role in enhancing fracture toughness than the fillers. It is unreasonable to rely solely on the loss factor for bulk energy dissipation. The addition of sacrificial bonds results in a chain segment experiencing greater binding force compared to the addition of fillers. This suggests that the chain segment consumes more energy during its movement. By calculating the length of the Kuhn chain segment and the Kuhn number, it is evident that the addition of sacrificial bonds results in a greater binding force for the chain segment than the addition of fillers, and this enhanced binding force increases the energy consumption during the motion of the chain segment.

Clinical outcomes of MANTA closure device in percutaneous endovascular aortic aneurysm repair.

OBJECTIVE: The MANTA device is a plug-based vascular closure device (VCD) designed for large bore femoral arterial access site closure. It showed promising results in transcatheter aortic valve replacement cases. In this study, we report our results and evaluate the MANTA VCD in percutaneous endovascular aortic aneurysm repair (pEVAR). METHODS: All data of consecutive patients who underwent an elective pEVAR between October 2018 and December 2022 were retrospectively reviewed. In all patients at least one common femoral artery was intended to close with the MANTA VCD. Depending on the sheath size, the 14Fr or 18Fr MANTA VCD was used. On the preoperative computed tomography scan, the diameter of the common femoral artery (CFA) was measured and the amount of calcification based on the Peripheral Arterial Calcium Scoring System (PACSS) was scored. Primary outcome was procedural technical success. Procedural technical success was defined as placement of the MANTA closure device resulting in vascular closure with patent CFA, without requiring immediate open or endovascular surgery. The secondary outcomes were access site complications requiring reintervention and all-cause mortality at 30-day follow-up. RESULTS: In total, 152 consecutive patients underwent pEVAR with 291 common femoral artery closure procedures with the Manta VCD. Mean age was 74.1 ± 6.4 years, with a mean body mass index of 27.7 ± 4.4 kg/m2. The mean diameter of the CFA was 10.5 ± 1.9 mm. In 52.6% of the cases, there were no calcification on the preoperative computed tomography scan. The 18Fr and 14Fr Manta VCD were used 169 and 122 times, respectively. The technical success rate was 96.6%. Major vascular complications were reported in 4.5% of the cases, without any death-related events. CONCLUSIONS: This single-center retrospective cohort study analyzed the procedural technical success, major vascular complications and all-cause mortality at 30-day follow-up of the MANTA vascular closure device in 152 pEVAR patients with 291 common femoral artery closure procedures. The technical success rate was 96,6%. Major vascular complications were reported in 4.5% of the cases, without any death related events. We concluded that the MANTA device is a safe and feasible option with a high rate of technical success in patients undergoing pEVAR.

Single-Center Experience With Inner-Branched Endograft for the Treatment of Pararenal Abdominal Aortic Aneurysms.

PURPOSE: To report a single-center result of patients with pararenal aneurysms treated with inner-branched endograft. MATERIALS AND METHODS: This retrospective study analyzed prospectively collected data of patients treated with elective inner-branched endovascular aneurysm repair (iBEVAR) using an Artivion® E-xtra custom-made endograft. Primary endpoints were clinical and technical success after iBEVAR. Secondary endpoints were overall survival, target vessel patency during follow-up, aneurysm-related mortality, and freedom from reintervention. RESULTS: Over a 56-month period, a total of 23 patients (19 men; 72.3±7.2 years) were treated with iBEVAR with a mean follow-up of 15 months. Technical success was achieved in 96% of procedures, incorporating 87 inner branches. Two (8.3%) intraoperative complications (target vessel dissection) were reported, without additional reinterventions needed. Two (8.3%) patients died within 30 days after initial procedure. One due to respiratory failure and the other from an ischemic stroke. During follow-up, 3 patients (13%) required reintervention, either to repair a type I or type III endoleak (n=2) or to place an iliac-branched device, that did not succeed during the initial iBEVAR procedure (n=1). Primary target vessel patency and freedom from reintervention during follow-up was, respectively, 98.9% and 87%. We revealed no aneurysm-related mortality. Overall survival was 78.3%. CONCLUSION: The present study confirms previous findings that iBEVAR on the Artivion® E-xtra design platform is an effective and safe procedure achieving high technical success rate in the treatment of pararenal abdominal aortic aneurysms. CLINICAL IMPACT: Inner branched stent-graft configuration combines the benefits of FEVAR and outer-branched stent-graft technology. Implementation of inner branches in stent-grafts is gradually becoming more widespread for the treatment of aneurysms. This report supports the safe and high technical success rate of inner branched stent-grafts in treatment of pararenal abdominal aortic aneurysms.

Fatal sepsis with peripheral necrosis due to Capnocytophagus canimorsus infection after dog bite: a case report.

Capnocytophaga canimorsus is a commensal bacterium in dogs and cats' saliva that can be transmitted to humans by licking, biting, or scratching. Although rare, an infection with C. canimorsus can have lethal consequences. Based on this case, the authors want to emphasize the importance of adequate wound care, close monitoring, and the use of prophylactic antibiotics after a dog bite or cat bite. Case Presentation: The authors present the case of a healthy 52-year-old patient with severe sepsis, disseminated intravascular coagulation, multiorgan failure, and peripheral necrosis of the lower arms, lower legs, nose, and genitals due to an infection with C. canimorsus after a dog bite. The patient eventually died on the ICU. Clinical Discussion: Due to the severeness of the sepsis, the patient was admitted to the ICU for maximum supportive care. As a last resort to save his life, an amputation of his nose, genitals, lower arms, and a transtibial amputation was proposed. In good consultation with the family, the decision was made not to perform this very mutilating surgery. The therapy was stopped because the loss in quality of life was too severe to justify continuation. The patient died soon after stopping supportive therapy. Conclusion: Based on this case, the authors would like to point out that, although rare, an infection with C. canimorsus can have devastating consequences with a high mortality and morbidity rate. It is important to know about this complication and to be aware of the importance of adequate wound care, close monitoring, and the use of prophylactic antibiotics after a dog bite or cat bite.

Molecular design of a highly matched and bonded interface achieves enhanced thermal boundary conductance.

Interfacial binding and phonon mismatch are two crucial parameters in determining thermal boundary conductance. However, it is difficult for polymer/metal interfaces to possess both significant interfacial binding and weak phonon mismatch to achieve enhanced thermal boundary conductance. Herein, we circumvent this inherent trade-off by synthesizing a polyurethane and thioctic acid (PU-TA) copolymer with multiple hydrogen bonds and dynamic disulfide bonds. Using PU-TA/aluminum (Al) as a model interface, we demonstrate that the thermal boundary conductance of the PU-TA/Al interfaces measured by transient thermoreflectance is 2-5 times higher than that of traditional polymer/Al interfaces, which is attributed to the highly matched and bonded interface. Furthermore, a correlation analysis is developed, which demonstrates that interfacial binding has a greater impact than phonon mismatch on thermal boundary conductance at a highly matched interface. This work provides a systematic understanding of the relative contributions of the two dominant mechanisms to thermal boundary conductance by tailoring the polymer structure, which has applications in thermal management materials.

Treatment of Aortoiliac Aneurysms: Compatibility of the E-liac Stent Graft (Artivion®, Iliac Branch Device) with Endurant II or IIs (Medtronic®, EVAR).

PURPOSE: Iliac branch devices (IBD) are widely used to treat aortoiliac aneurysms with an unfit distal landing zone for standard endovascular aneurysm repair (EVAR). The aim of this retrospective study was to examine the treatment of aortoiliac aneurysms with the combination of the Endurant II(s) stent graft system (Medtronic®) and the E-liac stent graft (Artivion®). MATERIALS AND METHODS: Data of all patients who underwent an EVAR combined with unilateral or bilateral IBD between January 2015 and January 2020 were analyzed. Primary outcomes were technical success at implantation (successful EVAR with IBD extension placement and patency of the grafts without type 1 or type 3 endoleak), and type 1b/3 endoleak, hypogastric artery patency and IBD-related reinterventions during follow-up. Secondary outcomes were all type 1 endoleak, all reinterventions, rupture, and mortality during follow-up. RESULTS: A total of 38 patients were treated with a combination of EVAR with IBD. Technical success was 94.7% (n = 36/38). The 30-day survival was 100%. Median follow-up time was 31 months (range 8-56). During follow-up, no patients developed type 1b or type 3 endoleak and all hypogastric arteries at the side of IBD remained patent. The overall reintervention rate at 12 months follow-up was 5.3% (n = 2/38) and the IBD-related reintervention rate was 2.6% (n = 1/38). CONCLUSION: The combination of the Endurant II(s) and the E-liac stent graft system is an effective and safe procedure for patients with an aortoiliac aneurysm. We confirm the high hypogastric artery patency rate using IBD. Furthermore, these devices have a high technical success rate even when it is combined with an Endurant II(s) EVAR main body.

Deficiency of TLR4 homologue RP105 aggravates outward remodeling in a murine model of arteriovenous fistula failure.

Arteriovenous access dysfunction is a major cause of morbidity for hemodialysis patients. The pathophysiology of arteriovenous fistula (AVF) maturation failure is associated with inflammation, impaired outward remodeling (OR) and intimal hyperplasia. RP105 is a critical physiologic regulator of TLR4 signaling in numerous cell types. In the present study, we investigated the impact of RP105 on AVF maturation, and defined cell-specific effects of RP105 on macrophages and vascular smooth muscle cells (VSMCs). Overall, RP105-/- mice displayed a 26% decrease in venous OR. The inflammatory response in RP105-/- mice was characterized by accumulation of anti-inflammatory macrophages, a 76% decrease in pro- inflammatory macrophages, a 70% reduction in T-cells and a 50% decrease in MMP-activity. In vitro, anti-inflammatory macrophages from RP105-/- mice displayed increased IL10 production, while MCP1 and IL6 levels secreted by pro-inflammatory macrophages were elevated. VSMC content in RP105-/- AVFs was markedly decreased. In vitro, RP105-/- venous VSMCs proliferation was 50% lower, whereas arterial VSMCs displayed a 50% decrease in migration, relative to WT. In conclusion, the impaired venous OR in RP105-/- mice could result from of a shift in both macrophages and VSMCs towards a regenerative phenotype, identifying a novel relationship between inflammation and VSMC function in AVF maturation.

Liposomal prednisolone inhibits vascular inflammation and enhances venous outward remodeling in a murine arteriovenous fistula model.

Arteriovenous fistulas (AVF) for hemodialysis access have a 1-year primary patency rate of only 60%, mainly as a result of maturation failure that is caused by insufficient outward remodeling and intimal hyperplasia. The exact pathophysiology remains unknown, but the inflammatory vascular response is thought to play an important role. In the present study we demonstrate that targeted liposomal delivery of prednisolone increases outward remodeling of the AVF in a murine model. Liposomes accumulate in the post-anastomotic area of the venous outflow tract in which the vascular pathology is most prominent in failed AVFs. On a histological level, we observed a reduction of lymphocytes and granulocytes in the vascular wall. In addition, a strong anti-inflammatory effect of liposomal prednisolone on macrophages was demonstrated in vitro. Therefore, treatment with liposomal prednisolone might be a valuable strategy to improve AVF maturation.

Vascular remodeling and intimal hyperplasia in a novel murine model of arteriovenous fistula failure.

OBJECTIVE: The arteriovenous fistula (AVF) still suffers from a high number of failures caused by insufficient outward remodeling and intimal hyperplasia (IH) formation from which the exact mechanism is largely unknown. A suitable animal model is of vital importance in the unraveling of the underlying pathophysiology. However, current murine models of AVF failure do not incorporate the surgical configuration that is commonly used in humans. Because the hemodynamic profile is one of the key determinants that play a role in vascular remodeling in the AVF, it is preferable to use this same configuration in an animal model. Here we describe a novel murine model of AVF failure in which the configuration (end-to-side) is similar to what is most frequently performed in humans. METHODS: An AVF was created in 45 C57BL/6 mice by anastomosing the end of a branch of the external jugular vein to the side of the common carotid artery with interrupted sutures. The AVFs were harvested and analyzed histologically at days 7, 14, and 28. Identical veins of unoperated-on mice served as controls. Intravenous near-infrared fluorescent fluorophores were used to assess the patency of the fistula. RESULTS: The patency rates at days 7, 14, and 28 days were 88%, 90%, and 50%, respectively. The mean circumference increased up to day 14, with a maximum 1.4-fold increase at day 7 compared with the control group (1.82 ± 0.7 vs 1.33 ± 0.3 mm; P = .443). Between days 14 and 28, the circumference remained constant (2.36 ± 0.2 vs 2.45 ± 0.2 mm; P = .996). At 7 days after surgery, the intimal area consisted mainly of an acellular layer that was structurally analogous to a focal adherent thrombus. Starting at 14 days after surgery, venous IH increased significantly compared with the unoperated-on group (14 days: 115,090 ± 22,594 µm(2), 28 days: 234,619 ± 47,828 µm(2), unoperated group: 2368 ± 1056 µm(2); P = .001 and P < .001, respectively) and was mainly composed of cells positive for α-smooth muscle actin. We observed leukocytes in the adventitial side of the vein at all time points. CONCLUSIONS: Our novel murine AVF model, which incorporates a clinically relevant configuration of the anastomosis, displays similar features that are characteristic of failing human AVFs. Moreover, our findings suggest that coagulation and inflammation could both potentially play an important role in the formation of IH and subsequent AVF failure. Near-infrared fluoroscopy was a suitable alternative for conventional imaging techniques. This murine AVF-model is a valuable addition to the AVF animal model arsenal.

Arteriovenous access failure: more than just intimal hyperplasia?

Haemodialysis vascular access patency is severely compromised by fistula non-maturation and access stenosis. Intimal hyperplasia (IH) is considered the culprit lesion in failed fistulas, resulting in luminal narrowing and stenosis. This review focuses on the biology and pathophysiology of fistula failure and highlights not only the classically associated IH but also some relatively neglected but potentially important contributors such as inadequate outward remodelling. In addition, the complex process and fragile balance of successful fistula maturation might be partially hindered by pre-existent chronic kidney disease-mediated vasculopathy. Further unravelling the (patho)physiology of outward remodelling and IH could contribute to novel therapies and enhance fistula patency.

Effects of octreotide on expression of L-type voltage-operated calcium channels and on intracellular Ca2+ in activated hepatic stellate cells.

BACKGROUND: The contractility of hepatic stellate cells (HSCs) may play an important role in the pathogenesis of cirrhosis with portal hypertension. The aim of this study was to research the effects of octreotide, an analogue of somatostatin, on intracellular Ca2+ and on the expression of L-type voltage-operated calcium channels (L-VOCCs) in activated HSCs, and to try to survey the use of octreotide in treatment and prevention of cirrhosis with portal hypertension complications. METHODS: HSC-T6, an activated HSCs line, was plated on small glass coverslips in 35-mm culture dishes at a density of 1 x 10(5)/ml, and incubated in DMEM media for 24 hours. After the cells were loaded with Fluo-3/AM, intracellular Ca2+ was measured by Laser Scanning Confocal Microscopy (LSCM). The dynamic changes in activated HSCs of intracellular Ca2+, stimulated by octreotide, endothelin-1, and KCl, respectively, were also determined by LSCM. Each experiment was repeated six times. L-VOCC expression in HSCs was estimated by immunocytochemistry. RESULTS: After octreotide stimulation, a significant decrease in the intracellular Ca2+ of activated HSCs was observed. However, octreotide did not inhibit the increases in intracellular Ca2+ after stimulation by KCl and endothelin-1. Moreover, octreotide did not significantly affect L-VOCC expression. These results suggest that neither L-VOCC nor endothelin-1 receptors in activated HSCs are inhibited by octreotide. CONCLUSIONS: Octreotide may decrease portal hypertension and intrahepatic vascular tension by inhibiting activated HSCs contractility through decreases in intracellular Ca2+. The somatostatin receptors in activated HSCs may be inhibited by octreotide.

Topical mydriatic and cycloplegic spray for Chinese children.

PURPOSE: To assess the efficacy and tolerance of mydriatic and cycloplegic spray versus drops for Chinese children. METHODS: The effects of the spray (cyclopentolate 0.25%, phenylephrine 0.625%, and tropicamide 0.5%) and the drops (cyclopentolate 1%, phenylephrine 0.5%, and tropicamide 0.5%) were evaluated in 29 children (58 eyes) in two separate sessions. There was a 1-week period between the applications of the spray and the drops. Dilated pupil size and refraction after cycloplegia were the primary outcome variables used to assess the efficacy. A subjective discomfort score was used to assess acceptance of the spray and the drops. RESULTS: The mean age of the study population was 4.33 +/- 1.39 years (range, 3 to 8 years). The mean pupil size was 6.9 mm for the spray and 6.6 mm for the drops. The spray appeared to be slightly more effective than the drops, with a mean difference of 0.3 mm that was statistically significant (P = .001, two-tailed t test). No statistically significant difference in cycloplegic response was found between the spray and the drops (P = .535, two-tailed t test). Administration of the spray caused less discomfort than did administration of the drops (P < .001, Wilcoxon signed-rank test). CONCLUSIONS: The spray system appears to be clinically equivalent to the drops for achieving effective pupil dilation and cycloplegia, even in a population with dark irides such as ours. Tolerability and acceptance improved because the spray was applied to the closed eyelids.