Five-year follow-up of randomized clinical trial for pre-emptive inferior mesenteric artery embolization during endovascular aneurysm repair.

OBJECTIVE: Type II endoleak (T2EL) is the most common type of endoleak after endovascular aneurysm repair (EVAR) and a common indication for reintervention due to late sac enlargement. Although pre-emptive embolization of the inferior mesenteric artery (IMA) has been proposed to prevent this, no studies have prospectively demonstrated its efficacy. This study aimed to prove the validity of IMA embolization during EVAR in selective cases by analyzing the mid-term outcomes of a randomized clinical trial (RCT). METHODS: This single-center, parallel-group, non-blinded RCT included participants at high risk of T2EL, characterized by a patent IMA in conjunction with one or more following risk factors: a patent IMA ≥3 mm in diameter, lumbar arteries ≥2 mm in diameter, or an aortoiliac-type aneurysm. The participants were randomly assigned to two groups in a 1:1 ratio: one undergoing EVAR with IMA embolization and the other without. The primary endpoint was T2EL occurrence. The secondary endpoints included aneurysm sac changes and reintervention. In addition to RCT participants, outcomes of patients with low risk of T2EL were also analyzed. RESULTS: The embolization and non-embolization groups each contained 53 patients. Five-year follow-up after the last patient enrollment revealed that T2ELs occurred in 28.3% and 54.7% of patients in the IMA embolization and non-embolization groups, respectively (P = .006). Both freedom from T2EL-related sac enlargement ≥5 mm and cumulative incidence of sac shrinkage ≥5 mm were significantly higher in the IMA embolization group than in the non-embolization group (95.5% vs 73.6% at 5 years; P = .021; 54.2% vs 33.6% at 5 years; P = .039, respectively). The freedom from T2EL-related sac enlargement ≥10 mm, an alternative indicator for T2EL-related reintervention, showed similar results (100% vs 90.4% at 5 years; P = .019). Outcomes in the low-risk group were preferable than those in the non-embolization group and comparable to those in the IMA embolization group. CONCLUSIONS: A lower threshold for pre-emptive IMA embolization when implementing EVAR would be more appropriate if limited to patients at high risk of T2ELs.

Treatment With Small Molecule Inhibitors of Advanced Glycation End-Products Formation and Advanced Glycation End-Products-Mediated Collagen Cross-Linking Promotes Experimental Aortic Aneurysm Progression in Diabetic Mice.

Background Although diabetes attenuates abdominal aortic aneurysms (AAAs), the mechanisms by which diabetes suppresses AAAs remain incompletely understood. Accumulation of advanced glycation end- (AGEs) reduces extracellular matrix (ECM) degradation in diabetes. Because ECM degradation is critical for AAA pathogenesis, we investigated whether AGEs mediate experimental AAA suppression in diabetes by blocking AGE formation or disrupting AGE-ECM cross-linking using small molecule inhibitors. Methods and Results Male C57BL/6J mice were treated with streptozotocin and intra-aortic elastase infusion to induce diabetes and experimental AAAs, respectively. Aminoguanidine (AGE formation inhibitor, 200 mg/kg), alagebrium (AGE-ECM cross-linking disrupter, 20 mg/kg), or vehicle was administered daily to mice from the last day following streptozotocin injection. AAAs were assessed via serial aortic diameter measurements, histopathology, and in vitro medial elastolysis assays. Treatment with aminoguanidine, not alagebrium, diminished AGEs in diabetic AAAs. Treatment with both inhibitors enhanced aortic enlargement in diabetic mice as compared with vehicle treatment. Neither enhanced AAA enlargement in nondiabetic mice. AAA enhancement in diabetic mice by aminoguanidine or alagebrium treatment promoted elastin degradation, smooth muscle cell depletion, mural macrophage accumulation, and neoangiogenesis without affecting matrix metalloproteinases, C-C motif chemokine ligand 2, or serum glucose concentration. Additionally, treatment with both inhibitors reversed suppression of diabetic aortic medial elastolysis by porcine pancreatic elastase in vitro. Conclusions Inhibiting AGE formation or AGE-ECM cross-linking enhances experimental AAAs in diabetes. These findings support the hypothesis that AGEs attenuate experimental AAAs in diabetes. These findings underscore the potential translational value of enhanced ECM cross-linking as an inhibitory strategy for early AAA disease.

Mechanisms and efficacy of metformin-mediated suppression of established experimental abdominal aortic aneurysms.

Objective: Metformin treatment attenuates experimental abdominal aortic aneurysm (AAA) formation, as well as reduces clinical AAA diameter enlargement in patients with diabetes. The mechanisms of metformin-mediated aneurysm suppression, and its efficacy in suppressing established experimental aneurysms, remain uncertain. Methods: Experimental AAAs were created in male C57BL/6J mice via intra-aortic infusion of porcine pancreatic elastase. Metformin alone (250 mg/kg), or metformin combined with the 5' AMP-activated protein kinase (AMPK) antagonist Compound C (10 mg/kg), were administered to respective mouse cohorts daily beginning 4 days following AAA induction. Further AAA cohorts received either the AMPK agonist AICA riboside (500 mg/kg) as positive, or vehicle (saline) as negative, controls. AAA progression in all groups was assessed via serial in vivo ultrasonography and histopathology at sacrifice. Cytokine-producing T cells and myeloid cellularity were determined by flow cytometric analyses. Results: Metformin limited established experimental AAA progression at 3 (-85%) and 10 (-68%) days following treatment initiation compared with saline control. Concurrent Compound C treatment reduced this effect by approximately 50%. In metformin-treated mice, reduced AAA progression was associated with relative elastin preservation, smooth muscle cell preservation, and reduced mural leukocyte infiltration and neoangiogenesis compared with vehicle control group. Metformin also resulted in reduced interferon-γ-, but not interleukin-10 or -17, producing splenic T cells in aneurysmal mice. Additionally, metformin therapy increased circulating and splenic inflammatory monocytes (CD11b+Ly-6Chigh), but not neutrophils (CD11b+Ly-6G+), with no effect on respective bone marrow cell populations. Conclusions: Metformin treatment suppresses existing experimental AAA progression in part via AMPK agonist activity, limiting interferon-γ-producing T cell differentiation while enhancing circulating and splenic inflammatory monocyte retention.

Effects of leg compression and calf muscle contraction by active ankle motion on venous hemodynamics in sitting individuals.

OBJECTIVES: To clarify the effects of compression and active ankle motion on venous hemodynamics in healthy sitting individuals. METHODS: In the sitting position, 14 participants performed plantar flexion and dorsiflexion of the ankle for 3 s each without compression. Changes in the calf volume were recorded using air plethysmography. Subsequently, the process was repeated with the application of tubular elastic bandage (TEB), followed by anti-thrombotic stocking (ATS). RESULTS: The median interface pressure at the calf was 16 mmHg with TEB and 21 mmHg with ATS. Without compression (N), the median venous volume was 76 mL. This was reduced to 58 mL with TEB and 56 mL with ATS (p < .01 vs. N for both). On the other hand, ejection volume by plantar flexion in N (27 mL) was not significantly changed with TEB (31 mL) or ATS (31 mL). Also, ejection volume by dorsiflexion in N (53 mL, p < .001 vs. plantar flexion) was not significantly changed with TEB (53 mL, p < .01 vs. plantar flexion) or ATS (41 mL, p < .05 vs. plantar flexion). CONCLUSIONS: The venous volume, which is defined as the change in enclosed calf volume from elevation to dependency, in the sitting position reduced similarly with TEB and ATS; however, the ejection volumes did not change significantly. Dorsiflexion exerted a larger ejection volume than plantar flexion in the sitting position.

Perivascular Adipose Tissue Is a Major Source of Nitric Oxide in Saphenous Vein Grafts Harvested via the No-Touch Technique.

Background Saphenous vein grafts (SVGs) are broadly used in coronary artery bypass grafting despite their inferior patency compared with arterial grafts. Recently, the no-touch technique (NT), in which an SVG is harvested with a pedicle of perivascular adipose tissue (PVAT) without conduit distension, was shown to improve long-term patency compared with conventional preparation (CV), wherein outer tissue is removed with distension. The NT was also reportedly associated with reduced atherosclerosis. Although endothelial damage provoked by conventional distension may underlie poor patency when CV is performed, the precise mechanisms underlying the salutary effects of the NT have been unclear. Methods and Results Residual SVGs prepared with CV (CV-SVGs) or NT (NT-SVGs) were obtained during coronary artery bypass grafting. Nitric oxide (NO2-/NO3- (NOx)) levels after 24 hours of tissue culture were quantified. The protein expression and localization were analyzed. The isometric force of SVG strips was measured. NT-SVGs showed superior NOx production to CV-SVGs. PVAT generated the majority of NOx in NT-SVGs. PVAT highly expressed arginosuccinate synthase 1, a rate-limiting enzyme in the molecular circuit for NO synthesis, thereby continuously providing the substrate for NO. A substantial level of endothelial NO synthase was also expressed in PVAT. Pharmacological inhibition of arginosuccinate synthase 1 or endothelial NO synthase significantly suppressed the NOx production in NT-SVGs. PVAT induced vasorelaxation through NO production, even in the endothelium-denuded SVG strips. Conclusions Preserving PVAT was predominantly involved in the superior NOx production in NT-SVGs. Since NO plays crucial roles in suppressing atherosclerosis, this mechanism may greatly contribute to the excellent patency in NT-SVGs.

Hardness Sensed by Skin Palpation in Legs with Lymphedema Is Predominantly Correlated with Dermal Thickening.

Background: We aimed to clarify whether pathological changes in skin and subcutaneous tissue with lymphedema affected the skin hardness sensed by palpation. Methods and Results: In 50 patients with unilateral legs with lymphedema (LE), the skin hardness of the lower inner thigh and lower inner calf was determined using a scale ranging from 1 (softest) to 7 (hardest) based on palpation. Then, the skin hardness was correlated with the measurements of skin/subcutaneous tissue ultrasonography images obtained from the palpated parts. Multivariate logistic regression analysis demonstrated that dermal thickness was a significant factor that affected the difference in skin hardness between the LE and the contralateral asymptomatic leg for both thigh (p < 0.05) and calf (p < 0.01). When the thigh and calf in the LE were individually studied, subcutaneous echogenicity (p < 0.05), indicating subcutaneous inflammation/fibrosis, and subcutaneous thickness (p < 0.01) also seemed to affect skin hardness, respectively. Conclusions: The skin hardness sensed in the LE seemed to be affected predominantly by dermal thickening. In addition, the pathological changes in the subcutaneous tissue caused by LE seemed to have an impact on skin hardness. Clinical Trial Registration number 2020-150.

Hyperbaric Oxygen Therapy Is an Effective Adjunctive Therapy to Manage Treatment-Resistant Venous Leg Ulcers.

We report five cases of venous leg ulcers (VLU) that were resistant to conservative therapy for 22-119 months and were eventually healed via hyperbaric oxygen therapy (HBOT). In one patient, VLU recurred four times and was managed using HBOT, each time. The VLU sizes ranged from 18 to 68 cm2 before HBOT. HBOT was administered at 2.0 atmospheres absolute with 100% oxygen for 60 min per session, five sessions a week during hospitalization. All VLUs healed after 17-66 sessions of HBOT.

A pilot study using cell-mixed sheets of autologous fibroblast cells and peripheral blood mononuclear cells to treat refractory cutaneous ulcers.

BACKGROUND/AIMS: We invented a cell-mixed sheet consisting of autologous fibroblast cells and peripheral blood mononuclear cells (PBMNCs) to treat refractory cutaneous ulcers. These sheets secrete the growth factors needed throughout the wound healing process in animal models. METHODS: We performed this study as a pilot phase I clinical trial (UMIN-CTR: UMIN000031645). Fibroblast cells were isolated and cultured from the oral tissue, and PBMNCs were collected by apheresis. A cell-mixed sheet was prepared by co-culturing these collected cells for 3 days. The primary observation index was safety, including all adverse events. Additional observation indices were wound healing over 1, 3, and 6 months; wound healing rate at 7 days and 1, 3, and 6 months. RESULTS: Six patients with venous leg ulcers (VLUs) were enrolled in the study, including three patients who were treated with the cell-mixed sheet transplantation. One patient was excluded because no fibroblast cells grew from the oral tissue culture, and other two were excluded because the growth factor secreted from mixed-cell sheets did not reach the reference value. The VLUs of two patients who received the cell-mixed sheet transplantation healed, and the VLU in one patient decreased in size. CONCLUSIONS: This pilot study demonstrated that cell-mixed sheets might be a new topical intervention to treat VLUs. However, it was also suggested that this treatment might be limited when using autologous cells collected from patients with VLUs. Therefore, it may be necessary to use high-quality allogeneic cells instead of autologous cells to improve the feasibility of this treatment.

Treatment Results of Endovascular Aneurysm Repair Using the Parallel Stent-Graft Double D Technique for Distal Saccular Abdominal Aortic Aneurysms and Common Iliac Aneurysms.

BACKGROUND: Endovascular aneurysm repair (EVAR) using a bifurcated stent graft may involve technical challenges when aortic disease (aneurysm or dissection) consists of a length <70 mm between the inferior renal artery and aortic bifurcation or narrow aortic bifurcation that is common in asymmetric distal abdominal aortic aneurysms (AAAs) or iliac artery aneurysms (IAAs). We use EVAR with the double D technique (DDT-EVAR) for such cases, which involves straight type of stent grafts with same diameter in left and right that are deployed parallel to an aortic cuff that has been previously placed. In addition, DDT-EVAR can preserve the inferior mesenteric artery (IMA) for IAA. METHODS: DDT-EVAR was performed for 21 of 910 (2%) cases from April 2007 to April 2019 at our institution. The median patient age was 74 years (range, 52-85). Nineteen patients (90%) were men. Six patients (all saccular; 1 rupture) had AAAs, 12 had IAAs, and 3 had chronic type B aortic dissociation (TBAD) for re-entry closure. AAA and IAA had diameters of 45 mm (range, 34-71) and 34 mm (range, 25-58), respectively. An aortic cuff was used for 19 (90%) cases. Endurant II (Medtronic, Santa Rosa, CA) was used for 12 cases. The Excluder (W.L. Gore & Associates, Inc, Flagstaff, AZ) was used for 7 cases. Endurant II was used for 20 cases, and the VBX (W.L. Gore & Associates, Inc) was used for 1 case as stent-graft limbs. RESULTS: The procedural success rate was 100%. The median operative time was 146 min (range, 88-324). IMA planned for preservation was successful for all 12 cases. Type I and type III endoleaks were not observed. With TBAD, flow to the false lumen decreased or disappeared, and no complications during the hospital stay were associated with the procedure. For 2 patients whose procedure involved Endurant II stent-graft limb, limb occlusions were observed postoperatively, and reintervention was required. No other patients required additional treatment at a median follow-up of 18 months (range, 4-50). CONCLUSIONS: DDT-EVAR is a safe and straightforward technique for the treatment of distal AAA, common iliac artery aneurysm, and TBAD. It may help preserve the IMA and internal iliac artery, even when it is impossible to preserve them with a bifurcated stent graft.

Extracellular Fluid Content in the Legs of Patients with Chronic Venous Disease.

BACKGROUND: This study aimed to determine the factors that affect the extracellular fluid (ECF) content in the legs of patients with chronic venous disease (CVD). METHODS: Bioimpedance analysis and air plethysmography (APG) were performed in 79 patients with CVD who visited our clinic between September 2016 and March 2019. The normal right legs (N) of 14 healthy volunteers were also reviewed for comparison. The ratio of ECF resistance (Re) of the leg to that of the arm (ReL/ReA) was used to express the ECF content in the tested leg. The severity of CVD was expressed using the clinical, etiological, anatomical, and pathophysiological (CEAP) classification. RESULTS: The ReL/ReA decreased as the CEAP class increased (N: median; 0.81 [range 0.66-0.95], C0-1: 0.79 [0.60-0.98], C2: 0.77 [0.56-1.08], C3: 0.67 [0.57-0.85], C4: 0.64 [0.44-0.89]). Older age, female sex, and CEAP class affected the ReL/ReA, but body mass index did not. The ReL/ReA did not correlate with the parameters that were derived from APG, including the venous filling index. CONCLUSIONS: We found that the ECF content in legs of patients with CVD might be primarily affected by patient-related factors and CEAP class, as opposed to venous hemodynamics.

Endovascular Aneurysm Repair With Re-entry Closure in a Patient With Abdominal Aortic Aneurysm Concomitant With Acute Type B Aortic Dissection.

INTRODUCTION: Abdominal aortic aneurysm (AAA) concomitant with acute aortic dissection is rare. CASE REPORT: An acute type B aortic dissection involving AAA in a 58 year old woman is described. Computed tomography angiography demonstrated that the false lumen of the abdominal aorta including the aneurysm remained patent, secondary to entry sites in the abdominal aorta, bilateral external iliac arteries, and a membrane tear of the left renal artery (LRA). The aneurysm was isolated by endovascular aneurysm repair and LRA stenting; all entry sites were occluded by endovascular treatment that included covered stenting of the LRA. Imaging performed three months after the procedure confirmed complete thrombosis of the false lumen and AAA sac shrinkage. DISCUSSION: Endovascular treatment with covered stents is reported as an alternative strategy for treatment of AAA concomitant with acute aortic dissection involving a visceral artery.

Allogeneic fibroblast sheets accelerate cutaneous wound healing equivalent to autologous fibroblast sheets in mice.

BACKGROUND/AIMS: This study sought to confirm the difference of the wound-healing effect, cell survival, and immune response between autologous fibroblast sheets and allogeneic fibroblast sheets. METHODS: Regarding wound healing, autologous or allogeneic fibroblast sheets were transplanted onto a mouse cutaneous wound healing model and the wound contraction rate was evaluated. The luciferase-expressing fibroblast sheet was prepared and the survival of the cell sheet was evaluated by IVIS® after autologous or allogeneic transplantation. Histological evaluation was performed at five and 14 days after transplantation. RESULTS: Allogeneic fibroblast-sheet transplantation showed significant wound contraction at the early phase of wound healing, which was equivalent to that seen with the autologous fibroblast sheets. Luminescence of the autologous and allogeneic luciferase-expressing fibroblast sheets peaked on Day 5, and no luminescence was observed on Day 13. In the allogeneic fibroblast-sheet transplant group, a significant accumulation of immune cells was observed in the healed tissue but not in the early stage of wound healing. CONCLUSION: The allogeneic fibroblast sheets showed comparable rates of cell survival and wound-healing effects to those of the autologous fibroblast sheets, despite the subsequent immunogenic response. This result supports the potential practical clinical application of scaffold-free allogeneic fibroblast sheets based on the paracrine effect.

Interface Pressures Derived from a Tubular Elastic Bandage.

Objective: We sought to clarify the interface pressure (IP) when using a tubular elastic bandage (TEB) and examine the possibility for TEBs to provide IPs comparable to those provided by anti-thrombotic stockings. Materials and Methods: In 40 healthy patients, IPs were measured at the level of calf at its maximum diameter (C) and transition of the medial gastrocnemius muscle into the Achilles tendon (B1) while a single or double layer of TEBs (17.5 cm in circumference) were applied with the patient in a supine position. Results: Including both the C and B1 levels, circumferences and IPs showed a good correlation (single layer; r=0.72, double layer; r=0.75). The IP obtained with a single layer of TEB at the C level (median, 17 mmHg [range, 12-23 mmHg]) was higher than that at the B1 level (14 mmHg [11-18 mmHg], p<0.001). When double-layer TEB was used, the IP at B1 level increased to 18 (14-23) mmHg (p<0.001 vs. single layer). Conclusion: Considering the characteristics of TEBs and using a single or double layer appropriately, creating a pressure profile mimicking that of an anti-thrombotic stocking seemed to be feasible when using a TEB.

Endovascular Aneurysm Repair With Inferior Mesenteric Artery Embolization for Preventing Type II Endoleak: A Prospective Randomized Controlled Trial.

OBJECTIVE: This study aimed to evaluate the effect of inferior mesenteric artery (IMA) embolization during endovascular aneurysm repair (EVAR) in patients at high risk of type II endoleak (T2EL) in randomized controlled trial (RCT). SUMMARY BACKGROUND DATA: Several studies have demonstrated a reduction of T2EL by IMA embolization before EVAR. However, there have been no RCT confirming the efficacy of IMA embolization. METHODS: Patients scheduled for elective EVAR between April 2014 and March 2018 were eligible. Patients at high risk of T2EL (IMA patency with IMA ≥3 mm, LAs ≥2 mm, or an aortoiliac-type aneurysm) were prospectively randomized to receive EVAR with or without IMA embolization. The primary endpoint was occurrence of T2EL during follow-up. Secondary endpoints included aneurysmal sac changes, adverse events from IMA embolization, and reintervention rate due to T2EL. This trial is registered with the University Hospital Medical Information Network, number UMIN000022147. RESULTS: One hundred thirteen patients had high risk and 106 were randomized. In the intention-to-treat analysis, the incidence of T2EL was significantly lower in the embolization group [24.5% vs 49.1%; P = 0.009, absolute risk reduction = 24.5%; 95% confidence interval (CI), 6.2-40.5, number needed to treat = 4.1; 95% CI, 2.5-16.1]. The aneurysmal sac shrunk significantly more in the embolization group (-5.7 ±â€Š7.3 mm vs -2.8 ±â€Š6.6 mm; P = 0.037), and the incidence of aneurysmal sac growth related to T2EL was significantly lower in the embolization group (3.8% vs 17.0%; P = 0.030). There were no complications related to IMA embolization or reinterventions associated with T2EL. CONCLUSIONS: Our results demonstrated the effectiveness of IMA embolization during EVAR in high-risk patients for the prevention of T2EL, which is suggested for avoiding aneurysmal sac enlargement related to T2EL.

Regular Compression Therapy May Not Be Necessary for Lymphedema in Arms without a Subcutaneous Echo-Free Space.

BACKGROUND: To study the effect of prolonged complex decongestive therapy (CDT) on lymphedema in arms without a subcutaneous echo-free space (SEFS) on subcutaneous tissue ultrasonography. METHODS: Fifty-one patients with arm lymphedema treated for longer than 1 year using CDT in our clinic were retrospectively evaluated. Before starting CDT, subcutaneous tissue ultrasonography was performed to examine for the presence of an SEFS. Two-stage CDT was performed as recommended by the International Society of Lymphology. Limb circumference was measured, and limb volume was calculated at the initial and latest visits. RESULTS: In patients with lymphedema in which SEFS was observed anywhere in the arm on the initial visit (n = 25), the edema ratio was significantly reduced by a median of -15% (range, -106% to 17%; P < 0.001). On the other hand, in the arms with lymphedema in which SEFS was not observed (SEFS[-], n = 26), the edema ratio was not changed significantly by CDT (median, 1% [range, -30% to 23%]). In arms without an SEFS that were not treated using arm sleeves regularly (n = 15), no increase in edema ratio was observed (median, 1% [range, -29% to 16%]). CONCLUSIONS: In arms with lymphedema without SEFS, the effect of CDT on the reduction of arm volume is limited.

Reverse slider technique using the Endurant stent graft for accurate proximal sealing in hostile neck endovascular aneurysm repair.

This report introduces the reverse slider technique to obtain proximal sealing effectively in endovascular aneurysm repair in short or angulated necks. It is the deployment process of the stent graft main body by repeatedly rotating and reversing the external slider with slight loosening of the suprarenal stent. This method helps obtain accurate placement of the proximal edge and effective sealing on the greater curvature side even in short and angulated necks. It is an effective method of extending the proximal sealing zone. It is gained by changing the deployment process with the Endurant stent graft (Medtronic, Santa Rosa, Calif) as an existing popular device.

Compression Therapy Using Bandages Successfully Manages Acute or Subacute Lipodermatosclerosis.

We report nine cases with acute or subacute lipodermatosclerosis treated successfully using multilayer bandages. All patients were women aged 52-90 years. Before presenting to our clinic, all patients had been treated for a tentative diagnosis of cellulitis caused by bacterial infection or inflammation of unknown cause for 3-19 weeks without improvement. Initially, we instructed all patients or their caregivers regarding the bandaging technique to achieve an interface pressure of >40 mmHg. Subsequently, this technique was continued by patients/caregivers. Symptoms subsided within 2-7 weeks in all patients except one who had been noncompliant with the compression therapy.

Chimney Endovascular Aneurysm Repair Using Endurant Stent-Grafts With Bare Balloon-Expandable Stents for Patients With Juxtarenal Aortic Aneurysms.

PURPOSE: To evaluate the advantages of chimney endovascular aneurysm repair (chEVAR) using an Endurant stent-graft with uncovered balloon-expandable stents (BES) for patients with juxtarenal aortic aneurysms. MATERIALS AND METHODS: Twenty-two patients (mean age 78.5±9.0 years; 13 men) who underwent chEVAR using Endurant and uncovered BES between January 2014 and December 2017 were analyzed retrospectively. The maximum aneurysm diameter was 59.1±11.9 mm, and the proximal neck length was 5.2±2.9 mm. Of the 22 cases, 9 (40%) involved proximal neck angulation and 9 (40%) had a conical neck. Single and double chimneys were performed using BES in 19 and 3 cases, respectively. In 2 cases, an additional self-expanding covered stent was used inside the uncovered BES. RESULTS: The technical success was 91% (20/22) as 2 (9%) cases showed minor type Ia endoleak. No postoperative systemic complications or acute renal dysfunction (Acute Kidney Injury Network classification stage 2 or higher) were observed. The mean radiologic observation period was 16.1±9.6 months, and no aneurysm expansion (>5 mm) was observed during this time. The mean maximum aneurysm diameter decreased to 52.9±10.2 mm (p<0.001 vs preoperative), with an individual mean sac regression of 6.2±5.9 mm. Overall primary chimney stent patency was 100%. One of the 2 cases of intraoperative type Ia endoleak resolved at the 6-month imaging, and no new type Ia endoleaks developed in any cases at follow-up. No additional treatment- or aneurysm-related events were observed. CONCLUSION: Short-term outcomes of chEVAR using Endurant with uncovered BES have been favorable when covered stents were unavailable, and it can be useful for high-risk patients with juxtarenal aortic aneurysms.