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.

Early and Midterm Outcomes of Chimney Endovascular Aortic Repair for Ruptured Abdominal Aortic Aneurysms.

PURPOSE: To compare the outcomes of endovascular aortic aneurysm repair using a chimney technique (ch-EVAR) with those of the standard EVAR (st-EVAR) for ruptured abdominal aortic aneurysms (RAAA). MATERIALS AND METHODS: We implemented ch-EVAR for juxtarenal RAAA based on obvious anatomical indications after converting the strategy for RAAA from open repair to EVAR. A retrospective, cohort-based study was conducted on patients with RAAA who were treated using EVAR in our hospital between July 2011 and March 2022. EVAR cases were extracted, and outcomes were compared between ch-EVAR and st-EVAR. Patient clinical status, anatomical variables, treatment, and follow-up data were evaluated. RESULTS: A total of 56 (82%) and 12 (18%) patients were treated by st-EVAR and ch-EVAR, respectively. Thirty-day mortality rates were comparable between the 2 groups [8.9% in st-EVAR vs 8.3% in ch-EVAR (p= 0.95)]. Short-term outcomes showed that no type Ia endoleak occurred in either group. Midterm outcomes, including sac enlargement [7.5% in st-EVAR vs 0% in ch-EVAR (p= 0.37)], shrinkage [77.5% in st-EVAR vs 80.0% in ch-EVAR (p= 0.86)], and overall survival and freedom from aneurysm-related reintervention at 3 years [64.7% and 96.4% in the EVAR group vs 91.7% and 100% in the ch-EVAR group, respectively (p= 0.30 and 0.52)], were not significantly different between the 2 groups. CONCLUSION: Ch-EVAR for RAAA showed remarkably excellent outcomes, comparable to those of st-EVAR. Ch-EVAR is considered technically feasible in experienced centers. The indications for EVAR for RAAA may be further expanded using the chimney technique, resulting in overall improved outcomes for RAAA. CLINICAL IMPACT: This is a retrospective, single-center analysis of 68 patients with ruptured abdominal aortic aneurysms (RAAAs) treated by endovascular repair (EVAR) to investigate the efficacy of the chimney technique for juxtarenal RAAA. Thirty-day mortality rate was 8.3% for the chimney EVAR group, which was equivalent to that in the standard EVAR group. Mid-term outcomes including sac enlargement/shrinkage, overall survival, and freedom from aneurysm-related reintervention were comparable between the two groups. This report suggests the possibility of broadening the selection criteria of the current endovascular strategy using the chimney technique.

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 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.

Using bifurcated endoprosthesis after iliac artery recanalization for concomitant abdominal aortic aneurysm and chronic total occlusions of access routes.

OBJECTIVE: Concurrent abdominal aortic aneurysm (AAA) and unilateral iliac occlusion is a challenge in the implantation of bifurcated stent grafts (BFGs). The endovascular approach is less invasive than open surgery; the aortouni-iliac (AUI) graft with crossover femorofemoral bypass (CFFB) has many problems associated with extra-anatomic reconstruction. We attempted endovascular aneurysm repair (EVAR) using BFGs in such cases and evaluated the outcomes. METHODS: This was a retrospective study. Between October 2012 and December 2017, there were 649 patients who underwent surgery for AAA, of whom 32 patients underwent open reconstruction and 617 patients underwent endovascular aneurysm repair; 15 patients with unilateral occluded iliac arteries and AAA were included. The analysis included patients with unilateral iliac chronic total occlusion (CTO). The intraoperative, postoperative, and follow-up variables were reviewed. RESULTS: The occluded lesions were the common iliac artery in 5 patients, the common iliac artery-external iliac artery (EIA) in 2 patients, the EIA in 7 patients, and the EIA-common femoral artery in 1 patient. The mean occlusive length was 89.7 ± 43.6 mm, and the mean AAA size was 54.6 ± 5.6 mm. Technical success was achieved in 13 patients (87%). All patients underwent recanalization through the true lumen and stent placement. The only procedure-related complication was distal embolism, which was treated with intraoperative thrombectomy. Recanalization of CTO lesions was not possible in two patients (13%), who underwent AUI graft placement with CFFB. The 30-day mortality and morbidity rates were 0%. The mean follow-up periods were 12 and 32 months for patients who underwent BFG placement and AUI graft placement with CFFB, respectively. During follow-up, the primary patency rate of successfully recanalized arteries was 100%. Aneurysm size decreased in four patients who underwent BFG placement; no change was seen in the other 11 patients. Freedom from aneurysm-related events was 100%; no patient needed secondary interventions. All patients with claudication pain preoperatively reported improvement in their symptoms during follow-up. In addition, the ankle-brachial index improved significantly from 0.51 ± 0.25 preoperatively to 0.88 ± 0.20 postoperatively (P < .001) in patients who underwent BFG placement. CONCLUSIONS: Recanalization of unilateral iliac CTO lesions and placement of BFG in cases with concomitant aneurysmal disease and unilateral iliac occlusive disease demonstrated a significant primary patency rate with improvements in claudication and ankle-brachial index.

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.

Treatment of Cutaneous Ulcers with Multilayered Mixed Sheets of Autologous Fibroblasts and Peripheral Blood Mononuclear Cells.

BACKGROUND/AIMS: We have developed a mixed-cell sheet consisting of autologous fibroblasts and peripheral blood mononuclear cells with a high potency for angiogenesis and wound healing against refractory cutaneous ulcers in mouse and rabbit models. To increase the effectiveness of the mixed sheet, we developed a multilayered mixed sheet. METHODS: We assessed the therapeutic effects of multilayered sheets on cutaneous ulcers in mice. Growth factors and chemokines were assessed by enzyme-linked immunosorbent assay. Angiogenesis and fibroblast migration were measured by using tube formation and migration assays. Wound healing rate of cutaneous ulcers was evaluated in mice with diabetes mellitus. RESULTS: The concentration of secreted vascular endothelial growth factor, hepatocyte growth factor, transforming growth factor, C-X-C motif chemokine ligand (CXCL)-1, and CXCL-2 in multilayered sheets was much higher than that in single-layered mixed-cell sheets (single-layered sheets) and multilayered sheets of fibroblasts alone (fibroblast sheets). The supernatant in multilayered sheets enhanced angiogenic potency and fibroblast migration compared with single-layered and fibroblast sheets in an in vitro experiment. The wound healing rate in the multilayered sheet-treated group was higher compared with the no-treatment group (control) at the early stage of healing. Moreover, both vessel lumen area and microvessel density in tissues treated with multilayered sheets were significantly increased compared with tissues in the control group. CONCLUSION: Multilayered sheets promoted wound healing and microvascular angiogenesis in the skin by supplying growth factors and cytokines. Accordingly, our data suggest that multilayered sheets may be a promising therapeutic material for refractory cutaneous ulcers.

Venous hemodynamics assessed with air plethysmography in legs with lymphedema.

This study was conducted to identify specific abnormalities using the results from air plethysmography in legs with lymphedema. A routine air plethysmography exercise protocol was performed in 31 patients with unilateral leg lymphedema, and the results were compared with those of 53 patients with unilateral great saphenous vein reflux and 15 normal subjects. The venous filling index in legs with lymphedema (2.1 ± 1.2 mL/sec) was smaller than in legs with great saphenous vein reflux (6.4 ± 4.1 mL/sec, p < 0.05), but was not different from that in normal legs (1.9 ± 1.2 mL/sec). The ejection fraction was similar in all groups. The residual volume fraction in legs with lymphedema (35 ± 32%) was larger than that in normal subjects (13 ± 23%, p < 0.05), but was not significantly different from that in the contralateral leg of the lymphedema patients (32 ± 27%). In conclusion, we found no specific air plethysmography findings in uncomplicated lymphedema.

Aggressive Decongestion in Limbs with Lymphedema without Subcutaneous Echo-Free Space.

BACKGROUND: To study the impact of aggressive decongestion in limbs with lymphedema without subcutaneous echo-free space (SEFS) in subcutaneous tissue ultrasonography. METHODS: In 13 patients with arm lymphedema (ALE) (13 arms) and 16 patients with leg lymphedema (LLE) (18 legs) without SEFS, an aggressive decongestion was performed as the first phase of complex decongestive therapy. Measurements of circumference and calculation of limb volume were performed before and after the treatment. RESULTS: In ALE, no significant reduction in arm volume (median -63 [range -251 to 176] mL) or edema ratio (-4 [-15 to 12]%) was confirmed. On the other hand, a small but significant reduction in leg volume (-207 [-834 to 131] mL, P < 0.001) and edema ratio (-4 [-14 to 2]%, P < 0.01) was confirmed in LLE. CONCLUSION: In limbs with lymphedema without SEFS, the impact of aggressive decongestion seemed limited.

Identification of Anatomical Risk Factors for Type II Endoleak to Guide Selective Inferior Mesenteric Artery Embolization.

BACKGROUND: It is unclear which patients are the best candidates for inferior mesenteric artery (IMA) embolization to reduce type II endoleak (ELII). Therefore, this study aimed to identify the anatomical risk factors for ELII after endovascular aneurysm repair (EVAR) and to determine the best candidates for preventative, preoperative IMA embolization. MATERIALS AND METHODS: Between April 2007 and September 2014, 196 patients underwent standard EVAR. Anatomical risk factors of postoperative, persistent ELII were detected using logistic regression analysis. Preoperative treatment of the IMA occlusion in patients with anatomical risk factors was performed to reduce ELII. RESULTS: ELII was detected in 48 patients (24.5%). Overall, patency of the IMA (odds ratio [OR], 4.13; P = 0.004) and lumbar artery (LA) diameter ≥2.0 mm (OR, 3.30; P = 0.008) were significant risk factors for ELII, whereas an Endurant stent graft protected against ELII (OR, 0.22; P = 0.023). However, in patients with patent IMA, IMA diameter ≥3.0 mm (OR, 4.09; P = 0.011), LA diameter ≥2.0 mm (OR, 3.16; P = 0.043), and aortoiliac aneurysm (OR, 6.36; P = 0.026) were significant risk factors for ELII. Incidence rates of ELII in patients with and without these factors were 37.8% and 11.2%, respectively. ELII did not occur in patients with risk factors who underwent treatment of preoperative IMA occlusion. CONCLUSIONS: Patients with these risk factors are the candidates for undergoing treatment of preoperative IMA occlusion to reduce ELII.

Midterm Outcomes of Endovascular Aortic Aneurysm Repair with Carbon Dioxide-Guided Angiography.

BACKGROUND: Although iodinated contrast (IC) agents are commonly used in endovascular aneurysm repair (EVAR), perioperative use in patients with renal dysfunction or IC allergies is avoided. Carbon dioxide (CO2)-guided angiography is a promising alternative. We aimed to evaluate short-term and midterm outcomes of EVAR using CO2-guided angiography. METHODS: Three hundred eighty-one patients who underwent EVAR from January 2012 to September 2016 were retrospectively reviewed and divided into an IC-EVAR group (n = 351) and CO2-EVAR group (n = 30). Subjects in the CO2-EVAR group had severe renal dysfunction (n = 27) and IC allergy (n = 4). Intraoperative, postoperative, and follow-up variables were compared. RESULTS: Compared with the IC-EVAR group, preoperative serum creatinine level was significantly higher (2.0 vs. 0.92 mg/dL, P < 0.0001) and mean IC dose was significantly lower (18 vs. 55 mL, P < 0.0001) in the CO2-EVAR group. The fluoroscopy time, operative time, number of stent grafts placed, and technical success rates of the groups were similar; no type I and/or type III endoleaks were detected on completion angiography. There was no acute kidney injury and one case of intestinal necrosis in the CO2-EVAR group, potentially due to cholesterol embolism. Postoperative endoleak, enlargement of aneurysms, survival, freedom from secondary intervention, and renal function change up to 3 months, postoperatively, were similar between the groups. CONCLUSIONS: CO2-EVAR is technically feasible and exhibits prominent renal protection. However, consideration of the aortic lumen status remains an important challenge.

Age-related increase in Wnt inhibitor causes a senescence-like phenotype in human cardiac stem cells.

Aging of cardiac stem/progenitor cells (CSCs) impairs heart regeneration and leads to unsatisfactory outcomes of cell-based therapies. As the precise mechanisms underlying CSC aging remain unclear, the use of therapeutic strategies for elderly patients with heart failure is severely delayed. In this study, we used human cardiosphere-derived cells (CDCs), a subtype of CSC found in the postnatal heart, to identify secreted factor(s) associated with CSC aging. Human CDCs were isolated from heart failure patients of various ages (2-83 years old). Gene expression of key soluble factors was compared between CDCs derived from young and elderly patients. Among these factors, SFRP1, a gene encoding a Wnt antagonist, was significantly up-regulated in CDCs from elderly patients (≥65 years old). sFRP1 levels was increased significantly also in CDCs, whose senescent phenotype was induced by anti-cancer drug treatment. These results suggest the participation of sFRP1 in CSC aging. We show that the administration of recombinant sFRP1 induced cellular senescence in CDCs derived from young patients, as indicated by increased levels of markers such as p16, and a senescence-associated secretory phenotype. In addition, co-administration of recombinant sFRP1 could abrogate the accelerated CDC proliferation induced by Wnt3A. Taken together, our results suggest that canonical Wnt signaling and its antagonist, sFRP1, regulate proliferation of human CSCs. Furthermore, excess sFRP1 in elderly patients causes CSC aging.

Therapeutic strategies for cell-based neovascularization in critical limb ischemia.

Critical limb ischemia (CLI) causes severe ischemic rest pain, ulcer, and gangrene in the lower limbs. In spite of angioplasty and surgery, CLI patients without suitable artery inflow or enough vascular bed in the lesions are often forced to undergo amputation of a major limb. Cell-based therapeutic angiogenesis has the potential to treat ischemic lesions by promoting the formation of collateral vessel networks and the vascular bed. Peripheral blood mononuclear cells and bone marrow-derived mononuclear cells are the most frequently employed cell types in CLI clinical trials. However, the clinical outcomes of cell-based therapeutic angiogenesis using these cells have not provided the promised benefits for CLI patients, reinforcing the need for novel cell-based therapeutic angiogenesis strategies to cure untreatable CLI patients. Recent studies have demonstrated the possible enhancement of therapeutic efficacy in ischemic diseases by preconditioned graft cells. Moreover, judging from past clinical trials, the identification of adequate transplant timing and responders to cell-based therapy is important for improving therapeutic outcomes in CLI patients in clinical settings. Thus, to establish cell-based therapeutic angiogenesis as one of the most promising therapeutic strategies for CLI patients, its advantages and limitations should be taken into account.

Innovative Procedure for Inferior Mesenteric Artery Embolization Using the Amplatzer Vascular Plug 4 during Endovascular Aneurysm Repair.

PURPOSE: The aim of this study is to present an easy and quick technique for embolization of the inferior mesenteric artery (IMA) during endovascular aneurysm repair (EVAR). TECHNIQUE: We performed IMA embolization using a conventional EVAR device alone with the femoral artery approach during EVAR, which has not been reported previously. First, a 16F or 18F DrySeal Sheath is inserted from the femoral artery into the site around the IMA. Second, cannulation is performed in the IMA with an angiography catheter having a 0.038-inch inner lumen that is used for gate cannulation during EVAR. Third, IMA embolization is performed using the Amplatzer Vascular Plug 4 (AVP4). The use of the DrySeal Sheath facilitates cannulation of the IMA, and its combination with a stent-graft balloon allows the AVP4 to be placed at the root of the IMA without deviation of the catheter. The success rate of the procedure was 90.9% (30/33 cases). The median procedure time was 11.6 min. No complications due to IMA embolization were noted. CONCLUSION: This procedure enables safe and quick placement of the AVP4 in the IMA using the catheter insertion approach from the femoral artery, which has been conventionally regarded as difficult.

Treatment Options for Celiac Stenosis and Pancreaticoduodenal Artery Aneurysms.

Celiac stenosis may result in a pancreaticoduodenal artery aneurysm (PDAA). Celiac stenosis with a PDAA is rare and treatment guidelines are absent. Here, we report 4 cases of celiac stenosis treated using different methods. Of these, 3 involved PDAAs. The PDAAs were successfully treated with coil embolization. For celiac stenosis, we performed open surgery for decompression in 1 patient, stenting in 2 patients, and bypass grafting in 1 patient. In the patients who underwent stenting, stent-associated thrombosis occurred. PDAAs can be treated with coil embolization; however, treatment of celiac stenosis with the endovascular approach might be difficult.

Hypoxic preconditioning reinforces cellular functions of autologous peripheral blood-derived cells in rabbit hindlimb ischemia model.

Peripheral blood mononuclear cell (PBMNC) is one of powerful tools for therapeutic angiogenesis in hindlimb ischemia. However, traditional approaches with transplanted PBMNCs show poor therapeutic effects in severe ischemia patients. In this study, we used autograft models to determine whether hypoxic pretreatment effectively enhances the cellular functions of PBMNCs and improves hindlimb ischemia. Rabbit PBMNCs were cultured in the hypoxic condition. After pretreatment, cell adhesion, stress resistance, and expression of angiogenic factor were evaluated in vitro. To examine in vivo effects, we autografted preconditioned PBMNCs into a rabbit hindlimb ischemia model on postoperative day (POD) 7. Preconditioned PBMNCs displayed significantly enhanced functional capacities in resistance to oxidative stress, cell viability, and production of vascular endothelial growth factor. In addition, autologous transplantation of preconditioned PBMNCs significantly induced new vessels and improved limb blood flow. Importantly, preconditioned PBMNCs can accelerate vessel formation despite transplantation on POD 7, whereas untreated PBMNCs showed poor vascularization. Our study demonstrated that hypoxic preconditioning of PBMNCs is a feasible approach for increasing the retention of transplanted cells and enhancing therapeutic angiogenesis in ischemic tissue.