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A systematic review and meta-analysis of randomised controlled trials (RCTs) was performed to determine the effectiveness and safety of drug coated balloon (DCB) angioplasty compared with uncoated plain balloon (PB) angioplasty in treating arteriovenous access stenosis. MEDLINE, Embase, Scopus, and the Cochrane Central Register of Controlled Trials were searched for RCTs comparing paclitaxel coated DCB and PB angioplasty for arteriovenous access stenosis. The last date of the literature search was 31 December 2020. Risk of bias of the retrieved studies was assessed with the Cochrane Collaboration tool for assessing risk of bias (RoB 2.0). The random effects model was used to estimate the risk of loss of target lesion patency (six and 12 months) and circuit patency (six and 12 months). Procedure related adverse events and mortality rate were also compared. Patency results were pooled using the time to event meta-analytical method and the quality of evidence was assessed according to the GRADE approach. Sixteen eligible trials, including 1 682 lesions, were included in the quantitative analysis for the efficacy and safety of paclitaxel coated DCBs. DCBs were associated with a lower risk of loss of target lesion patency at six months (HR 0.53, 95% CI 0.42 – 0.66) and 12 months (HR 0.60, 95% CI 0.47 – 0.76), and were also associated with improved six and 12 month circuit patency. Overall quality of evidence was moderate to low. Procedural complications were rare, and the risk of death up to 12 months was similar between the two groups (OR 1.03, 95% CI 0.68 – 1.56). Paclitaxel coated DCBs reduced the risk of loss of target lesion patency and circuit patency in arteriovenous access stenosis compared with PBs. Considering the heterogeneity of the included trials, there is a need to investigate optimal treatment regimens regarding drug dose and agent of the DCB and the treatment procedure. [ABSTRACT FROM AUTHOR]

Background: 3,5,3-triiodothyronine (T3) was found to decrease ischemia-reperfusion (I/R) injury of liver and myocardium in animal models when preconditioned 48 hours in advance of the I/R injury. The purpose of this study was to evaluate the effects of T3 preconditioning on renal I/R injury with different time intervals and to determine the changes in antioxidants, apoptosis, and nitric oxide synthase (NOS) in each condition. Methods: In male C57BL/6 mice, renal I/R injury was induced by temporary ligation of the bilateral renal pedicles for 45 minutes followed by a reperfusion period for 24 hours. Preconditioning with intraperitoneal injection of T3 was performed 24 or 6 hours before or at the time of I/R injury. Results: From the histologic examination, tubular injury was decreased in mice preconditioned with T3 6 hours before I/R injury. The levels of proinflammatory cytokines were decreased with T3 preconditioning, either 6 hours or at the time of I/R injury. The levels of glutathione were increased in all treatment groups. Expressions of neuronal NOS were increased when preconditioned 6 hours before or at the time of I/R injury. The number of apoptotic tubular epithelial cell evaluated by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay was decreased when preconditioned immediately before I/R injury. Conclusion: Preconditioning with T3 6 hours or immediately before I/R injury had a protective effect on renal I/R injury. The changes of NOS and antiapoptosis, other than well-known antioxidative properties, may play a role in the effect of short-term preconditioning. [Copyright &y& Elsevier]

Percutaneous vertebroplasty is a widely used treatment for vertebral compression fracture. It is relatively safe, but it can be complicated by pulmonary or cerebral embolism caused by the cement injected during the procedure. Here, we present a case of a 69-year-old male with extensive deep vein thrombosis from the inferior vena cava to the right iliac and left femoral veins, which occurred 10 months after vertebroplasty. He was treated successfully by catheter-directed thrombolysis, angioplasty, and stenting. To the best of our knowledge, this is the first report of the successful treatment of delayed thrombosis caused by migrated cement inside the inferior vena cava. [Copyright &y& Elsevier]

Objectives: There are few long-term follow-up studies about the result of revascularization surgery for the treatment of popliteal artery entrapment syndrome (PAES). We performed this retrospective study to analyze the long-term result of revascularization surgery in patients with advanced PAES during the last 16 years. Methods: Twenty-two limbs in 18 consecutive patients with PAES were treated surgically at Seoul National University Hospital between January 1994 and December 2009. The preoperative diagnosis of PAES was made by duplex ultrasonography, three-dimensional computed tomography angiography, magnetic resonance imaging, or conventional angiography. The method of surgical approach was determined by the extent of arterial occlusion in preoperative images. Results: The mean age was 31 years old and the majority of patients were men (94%). The chief complaints were claudication in 18 limbs, ischemic rest pain in three limbs, and toe necrosis in one limb. All 22 limbs underwent revascularization for advanced PAES with segmental arterial occlusion. Fourteen limbs underwent musculotendinous section and popliteo-popliteal interposition graft (13 posterior approaches, one medial approach), five femoropopliteal (below-knee) bypasses, one femoro-posterior tibial bypass, and two popliteo-posterior tibial bypasses. All revascularization surgeries were performed with reversed saphenous veins. The overall primary graft patency rates at 1, 3, and 5 years were 80.9%, 74.6%, and 74.6%, respectively. Comparing 5-year graft patency according to the extent of arterial occlusion, patients with occlusion confined to the popliteal artery (n = 14) showed a better patency rate than patients with occlusion extended beyond the popliteal artery (n = 8) with no statistical significance (83.6% vs 53.6%; P = .053). Comparing 5-year graft patency according to the inflow artery, superficial femoral artery inflow (n = 6) showed a worse patency rate than popliteal artery inflow (n = 16) (30.0% vs 85.9%; P = .015). Conclusion: In advanced popliteal entrapment syndrome, longer bypass with superficial femoral artery inflow showed poor long-term graft patency rate. The graft patency rate was excellent in patients whose arterial occlusion was confined to the popliteal artery and treated by popliteal interposition graft with reversed saphenous vein. With these data, we suggest that longer bypass extending beyond the popliteal artery might only be indicated in patients with critical limb ischemia when the extent of disease does not allow short interposition graft. [Copyright &y& Elsevier]

Objective: Spontaneous isolated dissection of the superior mesenteric artery (SIDSMA) is extremely rare. Various treatment options are currently available, including conservative management, anticoagulation, endovascular stenting, and surgical repair. Herein, we present our experience in the treatment of symptomatic SIDSMA. Methods: A retrospective study was conducted on 14 consecutive patients with symptomatic SIDSMA between January 2000 and January 2010. All patients had acute onset abdominal pain. The decision to intervene was based on patient symptoms and signs, as well as the morphologic characteristics of superior mesenteric artery (SMA) dissection on computed tomography (CT) angiography. Endovascular stenting (ES) was indicated in patients with severe compression of the true lumen or dissecting aneurysm likely to rupture. Self-expandable stents were placed via a right common femoral approach. None of the patients underwent anticoagulation, and patients who underwent ES were maintained on antiplatelet therapy for 3 months postoperatively. Results: The median age of the study subjects was 59 years (range, 50-75 years). The median follow-up time was 27.5 months (range, 2-64 months). Treatment included conservative management without the use of anticoagulation in seven patients, ES in six, and necrotic bowel resection in one. Four patients with severe compression of the true lumen or large dissecting aneurysm underwent ES as a primary treatment. ES was additionally performed in two patients in whom initial conservative treatment failed (increasing dissecting aneurysm at 7-day follow-up CT scan in one and a reappearance of abdominal pain after resuming diet in the other). The median fasting time was significantly shorter in patients with primary ES (2.5 days) than in those managed conservatively (8.0 days). No complications associated with the SIDSMA or ES were developed. The patency of stents was demonstrated on follow-up CT scans up to 60 months (range, 1-60 months). Conclusions: Conservative management without anticoagulation can be applied successfully to the patients with symptomatic SIDSMA. Primary endovascular stenting is indicated if patients have suspected bowel ischemia, compression of the true lumen of the SMA >80%, or SMA aneurysm of >2.0 cm in diameter on initial CT scan. Endovascular stenting can also be provided to the patients in whom initial conservative treatment failed, as a rescue therapy. [Copyright &y& Elsevier]

Purpose: Computed tomography venography (CTV) with three-dimensional reconstruction can provide complementary road maps for varicose vein (VV) surgery. The purpose of this study is to verify the role of CTV in the treatment of VV in terms of advantages and complications. Methods: Ninety-four consecutive patients with VV underwent conventional high ligation, stripping, and varicosectomy by a single vascular surgeon in 2007. All patients were evaluated with duplex ultrasound and CTV. Patients with renal dysfunction, allergy to radiocontrast, telangiectasia only, or treated by endovenous laser therapy (EVLT) were excluded from the study. Computed tomography (CT) examination was performed with a 16-Multidetector CT scanner (Siemens, Erlangen, Germany) and 3D images were reconstructed by personal computer-based software (Rapidia, Infinitt, Seoul, Korea). Medical records and the CT images were reviewed retrospectively. Results: VV surgeries were done in 127 limbs of 94 patients (both in 33, right in 29, and left in 32). There were 56 females and 38 males with the mean age of 57 years (range, 28-79 years). The CEAP classification was C2-3 EpAsPr. Perforators larger than 1 mm near the varicose veins were detected and marked on the CT volume-rendering images. The average numbers of perforators marked by CTV were 12.07 ± 4.27 in each limb. The perforators were evaluated by duplex for the presence of reflux (≥0.5 sec). Mean number of perforators with reflux in each limb was 1.41 ± 1.67, which were ligated during the surgery. Incidental detections of other disease were done in six patients, including uterine myomas, an ovarian cyst, a gallstone, a scrotoal varicocele, and a pes anserine bursitis. Operation was performed with the CTV images on screen. CTV was helpful in designing the operation in most patients. Three-D CTV images of saphenopopliteal junction especially provided thorough understanding of the complex variable anatomy of the lesion. There were no CT-related complications, such as renal dysfunction or allergic reaction. Conclusions: CT venography can provide excellent road map for VV surgery without significant complications. It cannot replace duplex ultrasound, but can provide powerful 3D images for designing operation as well as education and research. [Copyright &y& Elsevier]

Purpose: Since the publication of Dialysis Outcomes Quality Initiative (DOQI) guidelines, the use of native veins for the construction of arteriovenous fistulas (AVF) for hemodialysis has been highly recommended rather than prosthetic arteriovenous grafts (AVG). Upper arm basilic vein transposition (BVT) has been accepted widely, with superior patency compared with AVG, but only a few studies have reported outcomes of forearm BVT (FBVT). This study evaluated the efficacy of FBVT compared with direct AVF (DAVF) and AVG in a tertiary referral center. Methods: From January 2005 to December 2007, 461 patients underwent AV access for hemodialysis in Seoul National University Hospital. We retrospectively reviewed the medical records and dialysis sheets and evaluated the current AVF function in the outpatient clinic or by telephone interviews. Patients were grouped by the operation type: DAVF, FBVT, and AVG. The outcomes compared were primary, assisted-primary and secondary patency rates, maturation failure, and complications. Result: The mean age was 59 years (range, 14-92 years), and 280 patients (60.7%) were male. By operation type, the 461 accesses were 389 DAVF (84.4%), 34 FBVT (7.4%), and 38 AVG (8.2%). Mean follow-up duration was 21 months (range, 1-51 months). The primary patency rates for DAVF, FBVT, and AVG were 67.6%, 41.5%, 35% at 12 months and 53.9%, 30.2%, 10.3% at 24 months, respectively. The secondary patency rates were 89.2%, 79.1%, 78.3% at 12 months and 83.8%, 74.4%, 64.9% at 24 months, respectively. Maturation failure occurred in five DAVF patients and in one FBVT patient. The infection rate was 0.3% in DAVF and 12.5% in AVG, but no infection occurred in patients with FBVT. Multivariate analysis revealed that age and history of previous access were associated with lower primary patency. Conclusion: Forearm BVT showed an acceptable, high 2-year patency rate and fewer thromboses and infectious complications than AVG. Forearm BVT could be considered before forming an upper arm AVF or forearm AVG, if the basilic vein is available. [Copyright &y& Elsevier]

Objective: About a quarter of peripheral vein grafts fail due in part to intimal hyperplasia. The proliferative capacity and response to growth inhibitors of medial smooth muscle cells and adventitial fibroblasts in vitro were studied to test the hypothesis that intrinsic differences in cells of vein grafts are associated with graft failure. Methods: Cells were grown from explants of the medial and adventitial layers of samples of vein grafts obtained at the time of implantation. Vein graft patency and function were monitored over the first 12 months using ankle pressures and Duplex ultrasound to determine vein graft status. Cells were obtained from veins from 11 patients whose grafts remained patent (non-stenotic) and from seven patients whose grafts developed stenosis. Smooth muscle cells (SMCs) derived from media and fibroblasts derived from adventitia were growth arrested in serum-free medium and then stimulated with 1 μM sphingosine-1-phosphate (S1P), 10 nM thrombin, 10 ng/ml epidermal growth factor (EGF), 10 ng/ml platelet-derived growth factor-BB (PDGF-BB), PDGF-BB plus S1P, or PDGF-BB plus thrombin for determination of incorporation of [3H]-thymidine into DNA. Cells receiving PDGF-BB or thrombin were also treated with or without 100 μg/ml heparin, which is a growth inhibitor. Cells receiving thrombin were also treated with or without 150 nM AG1478, an EGF receptor kinase inhibitor. Results: SMCs and fibroblasts from veins of patients that developed stenosis responded more to the growth factors, such as PDGF-BB alone or in combination with thrombin or S1P, than cells from veins of patients that remained patent (P = .012). In addition, while PDGF-BB-mediated proliferation of fibroblasts from grafts that remained patent was inhibited by heparin (P < .03), PDGF-BB-mediated proliferation of fibroblasts from veins that developed stenosis was not (P > .5). Conclusion: Inherent differences in the proliferative response of vein graft cells to PDGF-BB and heparin may explain, in part, the variability among patients regarding long term patency of vein grafts. [Copyright &y& Elsevier]

Objective: Increased blood flow causes neointimal atrophy, whereas relief of wall tension with an external wrap causes arterial medial atrophy. To study the effects of blood flow and wall tension separately and together, we applied tight or loose wraps on high-flow or normal-flow iliac arteries in baboons. Method: Baboon external iliac arteries were wrapped with loose-fitting and tight-fitting expanded polytetrafluoroethylene (ePTFE), leaving part unwrapped. A downstream arteriovenous fistula was constructed on one side to increase blood flow approximately twofold. The arteries were perfusion-fixed with 10% formalin after 4 (n = 5) and 28 days (n = 5). Results: At 4 days, compared with the unwrapped artery, the loosely and tightly wrapped normal-flow artery showed significant medial atrophy (23% and 30%, respectively; P < .05). The tightly wrapped artery showed a loss of cells (27%; P = .02) but no change in cell density. At 28 days, the medial cross-sectional area was decreased by the tight wrap and loose wrap under normal (45% and 28%, respectively; P < .05) and high (43% and 29%, respectively; P < .05) flow. High flow did not alter the effect of wrapping nor did it affect the unwrapped medial area. At 28 days, the normal and high flow tightly wrapped media showed an insignificant loss of cells but had increased cell density (47% and 30%, respectively; P < .05), suggesting preferential loss of extracellular matrix. Decorin was expressed at the late time only in the tightly wrapped normal and high-flow media and was associated with tight packing of the collagen, as detected by picrosirius red staining. Conclusion: Loose-fitting and tight-fitting ePTFE wraps induced an inflammatory foreign body response that caused medial atrophy with loss of cells and extracellular matrix; the tight wrap was more effective. High blood flow did not prevent or augment medial atrophy. [Copyright &y& Elsevier]

Regardless of the type of arterial reconstruction, luminal narrowing (stenosis or restenosis) develops in approximately one third of the vessels. In the past, the focus of research has been on the mechanisms of stenosis (intimal hyperplasia, pathologic remodeling) and pharmacologic approaches to prevention. An alternative approach is to induce intimal atrophy after luminal narrowing has developed, thus limiting treatment to only those patients that develop a problem. This approach to treat established disease by reducing wall mass through induction of cell death and extracellular matrix removal would be particularly useful for treating stenosis in synthetic bypass grafts or stented vessels, in which intimal hyperplasia is the primary mechanism of stenosis. This approach may be applicable as well to other vascular proliferative disorders, such as pulmonary hypertension and chronic transplant arteriopathy. Proof of principle has been shown in experiments with antibodies to platelet-derived growth factor (PDGF) receptors that cause neointimal regression in baboon polytetrafluoroethylene (PTFE) grafts and with angiotensin-converting enzyme inhibitors that induce medial atrophy in hypertensive arteries. Possible molecular targets could include PDGF receptors, A20, and BMP4. Further studies are needed to determine the utility of such a therapeutic approach to vascular disease. [Copyright &y& Elsevier]

We report a case of a 25-year-old Caucasian female with a septic thrombosis in the inferior vena cava (IVC) which contained a toothpick. She was admitted with fever and abdominal pain for 2 weeks. Computed tomography scan showed thrombus with air density in the suprarenal IVC. However, there was no evidence of duodenocaval fistula. Because of the patient''s reluctance for surgery, endovascular therapy was tried. A partially-deployed nitinol stent was used as a filter, and aspiration thrombectomy was performed. Unexpectedly, a toothpick was retrieved within the stent. Anticoagulants and antibiotics were administered. A follow-up computed tomography after 2 months showed total resolution of the residual thrombus. [ABSTRACT FROM AUTHOR]

Purpose: To compare the efficacy of lymph node (LN) embolization using N-butyl cyanoacrylate versus ethanol sclerotherapy in the management of symptomatic postoperative pelvic lymphorrhea.Materials and Methods: Thirty-three patients with 40 instances of symptomatic postoperative lymphorrhea were treated with either LN embolization or sclerotherapy at Seoul National University Hospital from January 2009 to July 2017 and were retrospectively included (LN embolization group: 24 lymphoceles of 19 patients, mean age of 59.29 years; sclerotherapy group: 16 lymphoceles of 14 patients, mean age of 60.95 years). The types of operations were hysterectomy and bilateral oophorectomy with pelvic lymph node dissection (n = 9), radical prostatectomy (n = 3), and renal transplantation (n = 2) for the sclerotherapy group and radical prostatectomy (n = 10) and hysterectomy and bilateral oophorectomy with pelvic lymph node dissection (n = 9) for the LN embolization group. The 3 most common indications of treatment were lower extremity edema (n = 11), pain (n = 11), and fever (n = 8). The amount of leak before treatment (initial daily drainage) and clinical outcomes, including the clinical success rate in 3 weeks, treatment period, and complication rate were compared between both groups.Results: LN embolization showed a higher 3-week clinical success rate than sclerotherapy in a univariate analysis (83.3% and 43.8%, P = .026). There was no statistically significant difference in the treatment period and the complication rate (7.1 days and 12.3 days, P = .098; 8.3% and 25.0%, P = .184).Conclusions: LN embolization is more effective for treating postoperative pelvic lymphorrhea than sclerotherapy with similar safety. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the safety and efficacy of Lipiodol lymphangiography and 3 adjunctive N-butyl cyanoacrylate (NBCA) glue embolization techniques for the management of postoperative lymphatic leakage.Materials and Methods: This retrospective study included 27 patients with postoperative lymphatic leakage (17 with ascites, 3 with chylothorax, 6 with lymphoceles, and 1 with a skin fistula) who underwent Lipiodol lymphangiography for diagnostic and therapeutic purposes in 3 tertiary referral centers between August 2010 and January 2016. Adjunctive glue embolization was performed as needed by using 3 different techniques: "lymphopseudoaneurysm" embolization, closest upstream lymph node embolization, or direct upstream lymphatic vessel embolization.Results: Sixteen patients were observed to determine the therapeutic effect of lymphangiography, and 8 patients (50%) recovered without further embolization. In 16 patients, including 11 who underwent immediate embolization after lymphangiography and 5 who underwent delayed embolization, a total of 28 embolizations (12 lymphopseudoaneurysms, 14 lymph nodes, and 2 lymphatic vessels) were performed. The technical and clinical success rates of the adjunctive embolizations were 89% (25 of 28) and 94% (15 of 16), respectively. The overall clinical success rate was 85% (23 of 27). The median time from initial lymphangiography to recovery was 5 days. No procedure-related major complications were reported.Conclusions: Lipiodol lymphangiography and adjunctive glue embolization techniques appear safe and provide promising efficacy for the management of postoperative lymphatic leakage. [ABSTRACT FROM AUTHOR]

Objective: High blood flow induces neointimal atrophy in polytetrafluoroethylene (PTFE) aortoiliac grafts and a tight external PTFE wrap of the iliac artery induces medial atrophy. In both nonhuman primate models, atrophy with loss of smooth muscle cells and extracellular matrix (ECM) begins at ≤4 days. We hypothesized that matrix loss would be linked to cell death, but the factors and mechanisms involved are not known. The purpose of this study was to determine commonly regulated genes in these two models, which we hypothesized would be a small set of genes that might be key regulators of vascular atrophy. Methods: DNA microarray analysis (Sentrix Human Ref 8; Illumina, San Diego, Calif; ∼23,000 genes) was performed on arterial tissue from the wrap model (n = 9) and graft neointima from the graft model (n = 5) 1 day after wrapping or the switch to high flow, respectively. Quantitative reverse-transcription polymerase chain reaction (qRT-PCR) was also performed. Expression of this vascular atrophy gene set was also studied after Fas ligand-induced cell death in cultured smooth muscle cells and organ cultured arteries. Results: Microarray analysis showed 15 genes were regulated in the same direction in both atrophy models: 9 upregulated and 6 downregulated. Seven of nine upregulated genes were confirmed by qRT-PCR in both models. Upregulated genes included the ECM-degrading enzymes ADAMTS4, tissue plasminogen activator (PLAT), and hyaluronidase 2; possible growth regulatory factors, including chromosome 8 open reading frame 4 and leucine-rich repeat family containing 8; a differentiation regulatory factor (musculoskeletal embryonic nuclear protein 1); a dead cell removal factor (ficolin 3); and a prostaglandin transporter (solute carrier organic anion transporter family member 2A1). Five downregulated genes were confirmed but only in one or the other model. Of the seven upregulated genes, ADAMTS4, PLAT, hyaluronidase 2, solute carrier organic anion transporter family member 2A1, leucine-rich repeat family containing 8, and chromosome 8 open reading frame 4 were also upregulated in vitro in cultured smooth muscle cells or cultured iliac artery by treatment with FasL, which causes cell death. However, blockade of caspase activity with Z-VAD inhibited FasL-mediated cell death, but not gene induction. Conclusion: Seven gene products were upregulated in two distinctly different in vivo nonhuman primate vascular atrophy models. Induction of cell death by FasL in vitro induced six of these genes, including the ECM-degrading factors ADAMTS4, hyaluronidase 2, and PLAT, suggesting a mechanism by which the program of tissue atrophy coordinately removes extracellular matrix as cells die. These genes may be key regulators of vascular atrophy. [Copyright &y& Elsevier]

• Ta-implanted surface layer on ePTFE was fabricated via sputtering-based plasma immersion ion implantation technique. • Ta-implanted ePTFE exhibited excellent adhesion stability and an extremely low level of Ta ions released from the surface. • Surface properties of the Ta-implanted ePTFE were highly favorable for endothelial cell adherence and growth. • Ta-implanted ePTFE also possessed antithrombogenic properties, suppressing platelet adhesion and activation on the surface. Expanded polytetrafluoroethylene (ePTFE) has been successfully used as an artificial vascular graft material owing to its unique merits of fibrous structure, chemical stability, physical robustness, and nontoxicity. However, its insufficient endothelial cell affinity arising from its highly hydrophobic surface nature induces early thrombus formation and development of neointimal hyperplasia, leading to poor long-term patency rates. In this study, we demonstrate a novel rapid surface modification technique, termed as sputtering-based plasma immersion ion implantation (S-PIII), to elicit favorable vascular responses on the ePTFE surface. This technique enables rapid ion implantation of biologically compatible tantalum (Ta) into ePTFE surfaces, generating a nano-thick Ta-rich surface layer (<30 at.%) without any structural defects or loss of ePTFE's fibrous morphology. Surface properties of ePTFE, such as its biologically inert chemical structure and strong hydrophobicity, are ameliorated considerably after the S-PIII treatment, which is more favorable for endothelial cell (EC) adherence, spreading, and proliferation. In particular, compared to a bare ePTFE surface, Ta-implanted ePTFE possesses an antithrombogenic property, suppressing platelet adhesion and activation on its surface. From an in vivo pilot study with a canine aortic bypass model, Ta-implanted ePTFE demonstrates substantially suppressed early thrombosis with rapid formation of EC monolayers covering the luminal surface. [ABSTRACT FROM AUTHOR]