Two-Year Cumulative and Functional Patency after Creation of Endovascular Arteriovenous Hemodialysis Fistulae.

PURPOSE: To assess 2-year cumulative and functional patency of endovascular arteriovenous fistulae (endoAVF) created with the WavelinQ device. MATERIALS AND METHODS: Patients who had fistulae created at a single center from December 2019 to December 2020 were included in this retrospective study. Forty-three patients underwent endoAVF creation (22 females, 21 males). Data collected included patient demographics, location of fistula creation, interventions performed, and brachial artery flow before and after creation. Two-year cumulative and functional patency rates were assessed with Kaplan-Meier method, and variables that affected patency and maturation were examined using Cox proportional hazards model. RESULTS: Technical success was 95% (41/43), and in 4 patients, the fistula did not mature for dialysis use (9.7%). For the remaining 37 patients with endoAVF maturation, 25 had ulnar-ulnar fistulae, 10 had radial-radial fistulae, and 2 had interosseous artery-vein fistulae. Mean maturity time was 73 days, and brachial artery flow of >886 mL/min was predictive of maturation. Mean tunneled dialysis catheter removal time was 133 days. Number of interventions per patient-year was 0.38, where 8 were maturation procedures (5 vein elevations/transpositions and 3 coil embolizations) and 21 were maintenance angioplasties. Two-year cumulative/secondary and functional patency rates were 89.4% and 92.1%, respectively, with a mean follow-up of 665.7 days. Examined variables did not impact cumulative or functional patency. One adverse event was migration of coil to the heart, which was successfully retrieved at time of procedure. CONCLUSIONS: Two-year patency of 89.4% and functional patency of 92.1% were observed after endoAVF creation with WavelinQ device.

Arteriovenous Access for Hemodialysis: A Review.

Importance: Hemodialysis requires reliable vascular access to the patient's blood circulation, such as an arteriovenous access in the form of an autogenous arteriovenous fistula or nonautogenous arteriovenous graft. This Review addresses key issues associated with the construction and maintenance of hemodialysis arteriovenous access. Observations: All patients with kidney failure should have an individualized strategy (known as Patient Life-Plan, Access Needs, or PLAN) for kidney replacement therapy and dialysis access, including contingency plans for access failure. Patients should be referred for hemodialysis access when their estimated glomerular filtration rate progressively decreases to 15 to 20 mL/min, or when their peritoneal dialysis, kidney transplant, or current vascular access is failing. Patients with chronic kidney disease should limit or avoid vascular procedures that may complicate future arteriovenous access, such as antecubital venipuncture or peripheral insertion of central catheters. Autogenous arteriovenous fistulas require 3 to 6 months to mature, whereas standard arteriovenous grafts can be used 2 to 4 weeks after being established, and "early-cannulation" grafts can be used within 24 to 72 hours of creation. The prime pathologic lesion of flow-related complications of arteriovenous access is intimal hyperplasia within the arteriovenous access that can lead to stenosis, maturation failure (33%-62% at 6 months), or poor patency (60%-63% at 2 years) and suboptimal dialysis. Nonflow complications such as access-related hand ischemia ("steal syndrome"; 1%-8% of patients) and arteriovenous access infection require timely identification and treatment. An arteriovenous access at high risk of hemorrhaging is a surgical emergency. Conclusions and Relevance: The selection, creation, and maintenance of arteriovenous access for hemodialysis vascular access is critical for patients with kidney failure. Generalist clinicians play an important role in protecting current and future arteriovenous access; identifying arteriovenous access complications such as infection, steal syndrome, and high-output cardiac failure; and making timely referrals to facilitate arteriovenous access creation and treatment of arteriovenous access complications.

Real-World Experience With the Angio-Seal Closure Device: Insights From Manufacturer and User Facility Device Experience Database.

PURPOSE: Angio-Seal (Terumo Medical Corporations, Somerset, New Jersey) device is indicated for femoral arteriotomy closure. Real-world published data on complications are limited. We present 1 year of safety events involving Angio-Seal from the US Food and Drug Administration's post-market surveillance database of Manufacturer and User Facility Device Experience (MAUDE). Steps for managing frequent device-related problems are discussed. MATERIALS AND METHODS: Angio-Seal MAUDE data from November 2019 to December 2020 was classified according to (1) mode of device failure, (2) complication, (3) treatment, and (4) Cardiovascular and Interventional Radiological Society of Europe (CIRSE) adverse event classification system. RESULTS: There were 715 safety events, involving Angio-Seal VIP (93.1%), Evolution (5.7%), STS Plus (1.1%), and sizes 6F (62.5%) and 8F (37.5%). Failure mode involved unrecognized use of a damaged device (43.4%), failed deployment (20.1%), failed arterial advancement (6.3%), detachment of device component (4.9%), failed retraction (3.6%), operator error (1.1%), and indeterminate (20.6%). Of total, 44.8% of events were associated with patient harm. Complications involved minor blood loss (34.1%), hematoma (5.6%), significant blood loss (1.4%), and pseudoaneurysm (1.4%). Of total, 43.3% of cases required manual compression (MC), whereas 8.8% required more advanced intervention. Interventions included surgical repair (49.2%), thrombin injection (9.5%), balloon tamponade (6.3%), covered stent (4.8%), and unspecified (30.2%). Majority of safety events were CIRSE grade 1 (92.0%), followed by grades 2 (3.1%), 3 (4.6%), and 6 (deaths, 0.3%). Minority of devices were returned for manufacturer analysis (27.8%). CONCLUSIONS: The majority of safety events were associated with minor blood loss or local hematoma and could be addressed with MC alone. Most events were attributed to damaged device; however, very few devices were returned to manufacturer for analysis. This should be encouraged to allow for root cause analysis in order to improve safety profile of devices. System-level strategies for addressing barriers to under-reporting of safety events may also be considered. CLINICAL IMPACT: Our study highlights important safety events encountered in real-world practice with Angio-Seal closure device. The MAUDE database captures real-world device malfunctions not typically appreciated in conventional clinical trials. Our study provides valuable insight for clinician-users on anticipating and managing the most common device malfunctions. Additionally, our data provide feedback for manufactures to optimize product design and direct manufacturer user training to improve safety. Finally, we hope that the study promotes system-level strategies that foster reporting of safety events and undertaking of root cause analysis.

Vascular Closure Devices For Axillary Artery Access: A Systematic Review and Meta-Analysis.

PURPOSE: To evaluate the technical success and complication rates of vascular closure devices (VCDs) in the axillary artery. MATERIALS AND METHODS: MEDLINE and Embase were searched independently by two reviewers to identify observational studies from inception through October 2021. The following outcomes were meta-analyzed: technical success, hematoma, dissection, pseudoaneurysm, infection, and local neurological complications. Complications were also graded as mild, moderate, and severe. A logistic regression evaluating the influence of sheath size for the outcome of technical success rate was performed using individual patient-level data. RESULTS: Of 1496 unique records, 20 observational studies were included, totaling 915 unique arterial access sites. Pooled estimates were as follows: technical success 84.8% (95% confidence interval [CI]: 78%-89.7%, I2=60.4%), hematoma 7.9% (95% CI: 5.8%-10.6%, I2=0%), dissection 3.1% (95% CI: 1.3%-7.3%, I2=0%), pseudoaneurysm 2.7% (95% CI: 1.3%-5.7%, I2=0%), infection <1% (95% CI: 0%-5.7%, I2=20.5%), and local neurological complications 2.7% (95% CI: 1.7%-4.4%, I2=0%). There was a significant negative association between sheath size and technical success rate (odds ratio [OR]: 0.87 per 1 French (Fr) increase in sheath size, 95% CI: 0.80-0.94, p=0.0005). Larger sheath sizes were associated with a greater number of access-site complications (adjusted odds ratio [aOR]: 1.21 per 1 Fr increase sheath size, 95% CI: 1.04-1.40, p=0.013). CONCLUSIONS: Off-label use of VCDs in the axillary artery provides an 85% successful closure rate and variable complication rate, depending on the primary procedure and sheath size. Larger sheaths were associated with a lower technical success and greater rate of access-related complications. CLINICAL IMPACT: Safe arterial access is the foundation for arterial intervention. While the common femoral artery is a well established access site, alternative arterial access sites capable of larger sheath sizes are needed in the modern endovascular era. This article provides the largest synthesis to date on the use of vascular closure devices for percutaneous axillary artery access in endovascular intervention. It should serve clinicians with added confidence around this approach in terms of providing a reference for technical success and complications. Clinically, this data is relevant for patient consent purposes as well as for practice quality improvement in setting safety standards for this access site.

Objective Performance Goals Based on a Systematic Review and Meta-Analysis of Clinical Outcomes for Bare-Metal Stents and Percutaneous Transluminal Angioplasty for Hemodialysis-Related Central Venous Obstruction.

PURPOSE: To use safety and efficacy outcomes following treatment with percutaneous transluminal angioplasty (PTA) and/or stent placement for thoracic central venous obstruction in hemodialysis-dependent patients to establish objective performance goals (OPGs). METHODS: A systematic literature review and meta-analysis were conducted for articles published between January 1, 2000, and August 31, 2021. Efficacy outcomes included primary patency rates at 6 and 12 months, and safety outcomes included adverse events (AEs) categorized as access loss, procedure-related AEs, and serious AEs (SAEs). OPGs were derived from the upper and lower bounds of the 95% confidence intervals for primary patency and SAE rates. RESULTS: Of 66 articles reviewed, 17 met the inclusion criteria (PTA, n = 4; stent placement, n = 5; PTA/stent, n = 8). The 6- and 12-month primary patency rates for PTA were 50.9% and 36.7%, respectively. Based on these findings, the proposed 6- and 12-month primary patency OPGs identifying superiority against PTA were 66.5% and 52.6%, respectively, and those for noninferiority were 39.0% and 25.7%, respectively. For stent placement, the 6- and 12-month primary patency rates were 69.7% and 47.9%, respectively. The proposed 6- and 12-month primary patency OPGs identifying superiority were 82.1% and 64.1%, respectively, and those for noninferiority were 59.3% and 35.8%, respectively. SAE rates for PTA and stent placement were 3.8% and 8.1%, respectively. Proposed safety OPGs for noninferiority versus superiority for PTA and stent placement were 10.1% versus 1.4% and 13.6% versus 4.8%, respectively. CONCLUSION: The OPGs derived from real-world studies of PTA and stent placement may serve as a benchmark for future interventions indicated for this patient population.

The Use of Vascular Closure Devices for Brachial Artery Access: A Systematic Review and Meta-Analysis.

PURPOSE: To estimate the rates of technical success and adverse events of vascular closure devices (VCDs) in the brachial artery and compare the rates of adverse events with manual compression. MATERIALS AND METHODS: MEDLINE and Embase were searched for observational studies examining VCDs in the brachial artery. Meta-analyses were performed using random effects for the following outcomes: (a) technical success, (b) hematoma at the access site, (c) pseudoaneurysm, (d) local neurological adverse events, and (e) total number of adverse events. A pairwise meta-analysis compared VCD with manual compression for the outcomes of hematoma and the total number of adverse events. RESULTS: Of 1,761 eligible records, 16 studies including 510 access sites were included. Primary procedures performed were peripheral arterial disease interventions, percutaneous coronary intervention, and endovascular thrombectomy for ischemic stroke. The technical success rate was 93% (95% CI, 87%-96%; I2 = 47%). Data on the following adverse events were obtained via meta-analysis: (a) hematoma, 9% (5%-15%; I2 = 54%); (b) stenosis or occlusion at access site, 3% (1%-14%; I2 = 51%); (c) infection, 0% (0%-5%; I2 = 0%); (d) pseudoaneurysm, 4% (1%-13%; I2 = 61%); (e) local neurological adverse events, 5% (2%-13%; I2 = 54%); and (f) total number of adverse events, 15% (10%-22%; I2 = 51%). Angio-Seal success rate was 96% (93%-98%; I2 = 0%), whereas the ExoSeal success rate was 93% (69%-99%; I2 = 61%). When comparing VCD and manual compression, there was no difference in hematoma formation (relative risk, 0.75; 95% CI, 0.35-1.63; I2 = 0%; P = .47) or the total number of adverse events (relative risk, 0.75; 95% CI, 0.35-1.58; I2 = 76%; P = .45). CONCLUSIONS: Despite being off-label, studies suggest that VCDs in the brachial artery have a high technical success rate. There was no significant difference in adverse events between VCDs and manual compression in the brachial artery.

Percutaneous Hemodialysis Fistula Creation.

Two devices have been recently introduced to the European Union and North American clinical practice that allow for percutaneous creation of autogenous hemodialysis fistulae (percutaneous arteriovenous fistulae [pAVFs]). Although there are many similarities between the devices, there are several important differences. The adoption of either or both technologies by an interventionalist may be determined by the individual's familiarity and preferences. Current and future outcomes will shape the acceptance and use of this technology. This review focuses on the similarities and differences between the devices, procedures, published outcomes to date, and their interpretation and other clinical considerations toward the initiation of a successful pAVF program.

Uterine Artery Embolization for Pedunculated Subserosal Fibroids: A Systematic Review and Meta-Analysis.

PURPOSE: To provide a comprehensive overview of the literature assessing the safety and efficacy of uterine artery embolization (UAE) for patients with pedunculated subserosal fibroids. MATERIALS AND METHODS: MEDLINE and Embase databases were searched without language or publication type restrictions for observational studies to estimate safety (adverse events) and efficacy (devascularization, fibroid volume reduction, and uterine volume reduction) outcomes. Case reports were included to qualitatively report adverse events. Meta-analysis was performed for single proportions and mean changes with random-effects modeling. RESULTS: Of 98 eligible articles, 11 studies were included in the final analysis. Of the adverse events detailed in these cases, 5 events were mild, 2 were moderate (torsion of pedunculated fibroid requiring laparoscopic myomectomy and persistent bleeding after embolization requiring hysterectomy), and 1 was severe (fibroid necrosis causing bowel obstruction requiring bowel resection and hysterectomy). There were no deaths reported in the literature. The pooled risk of adverse events was 1.7% (95% confidence interval [CI], 0.29%-9.2%; 4 of 181; I2 = 0%). The pooled devascularization rate was 75.9% (95% CI, 62.4%-85.6%; 140 of 189; I2 = 75%) at 3.91 months of follow-up. The percent volume reduction of the dominant pedunculated fibroid was 38.6% (95% CI, 33.0%-44.2%; I2 = 0%) at 4.3 months of follow-up. The percent uterine volume reduction was 36.7% (95% CI, 30.3%-43.0%; I2 = 47%) at 3.5 months of follow-up. CONCLUSIONS: UAE for pedunculated subserosal fibroids has a low risk of adverse events and effectively reduces fibroid and uterine size.

Complication rates associated with antegrade use of vascular closure devices: a systematic review and pooled analysis.

BACKGROUND: Vascular closure devices (VCDs) have become a mainstay in endovascular interventions in recent years. On-label use only allows for retrograde interventions originating at the common femoral artery (CFA). However, off-label use in antegrade and/or superficial femoral artery (SFA) access has become more common in the treatment of peripheral arterial disease. Despite this, there is a paucity of comparative literature assessing individual VCD safety profiles and relative complication risks of CFA vs SFA applications. METHODS: MEDLINE and EMBASE systematic searches were performed from inception to October 2019 to identify studies assessing VCD use in antegrade CFA and SFA interventions. Abstract selection and data extraction were performed by two independent reviewers. Primary outcomes included bleeding-related complications, vessel occlusion or stenosis, embolization, pseudoaneurysm formation, or arteriovenous fistula formation. RESULTS: Twenty-four unique studies with 4124 vascular closure events via six unique VCDs were included (Angioseal, Exoseal, Femoseal, Glubran 2, Mynx, Starclose; 3698 CFA, 426 SFA). Pooled occurrence of all complications across closure devices used in the CFA and SFA ranged from 0.9% (Mynx) to 7.4% (Starclose) and 0% (Perclose) to 10.1% (Starclose), respectively, depending on VCD type. Clinically meaningful differences were identified between devices with a trend toward significance (P = .08 CFA, P = .07 SFA). Individual devices demonstrated a range of bleeding complication rates from 0.4% (Mynx) to 7.2% (Femoseal) for the CFA site and from 0% (Perclose) to 6.4% (Starclose) for the SFA site (P = .01 and P = .03, respectively). Significant heterogeneity between studies precludes definitive characterization of the device as cause for variations in bleeding complication rates. Pooled complication rates did not differ between the CFA and SFA arms (4.6% vs 5.8%, P = .56). Bleeding complication rates also did not differ between the CFA and SFA arms (3.6% vs 3.6%, P = .98). CONCLUSIONS: Clinically meaningful differences in overall pooled complications were identified between VCDs with a trend toward significance. Significant differences between VCDs exist with respect to bleeding risk. However, this must be interpreted with caution as these differences could be secondary to interstudy heterogeneity. Finally, no difference was identified between antegrade SFA and CFA VCD use with respect to overall complication and bleeding risks.

Endovascular community response to mortality data in use of paclitaxel devices for peripheral vascular disease.

OBJECTIVE: We examined the endovascular community response to data demonstrating increased mortality in paclitaxel devices for the treatment of peripheral arterial disease in femoropopliteal lesions. METHODS: A retrospective observational study using the Vascular Quality Initiative Peripheral Vascular Intervention registry dataset was performed to examine paclitaxel device use for peripheral arterial disease in femoropopliteal arteries treated from 2017 to 2019. A total of 41,707 patients and 52,208 procedures were analyzed during the study period. A post hoc analysis was performed to examine paclitaxel device use during selected periods in 2019. RESULTS: The total number of femoropopliteal procedures in 2017, 2018, and 2019 were 17,458, 21,140, and 21,322, respectively. Paclitaxel devices were used for 8852 arteries in 2017, 10,691 in 2018, and 6732 in 2019, which was significantly reduced in 2019 compared with 2017 or 2018 (P < .0001) and 2019 compared with the 2018 and 2017 volumes combined (P < .0001). Post hoc analysis of selected periods in 2019 demonstrated variable use throughout 2019. CONCLUSIONS: After the report of data with concerns of mortality associated with paclitaxel device use in 2018, a rapid reduction in overall paclitaxel device use was observed in 2019.

Hepatic Arterial Blood Flow Modulation in Patients with Hepatocellular Carcinoma: A Pilot Study of the Influence of Intraarterial Norepinephrine Assessed with CT Perfusion.

PURPOSE: This pilot study aims to evaluate the effect of hepatic intraarterial norepinephrine injection in vasculature modulation for hepatocellular carcinoma (HCC) tumors. MATERIALS AND METHODS: This is a single-center prospective study of patients with HCC with proven single-lobe tumors > 3 cm. Eight patients were included, with a mean age of 63 y ± 8. All patients had Barcelona Clinic Liver Cancer stage B HCC and an Eastern Cooperative Oncology Group performance status of 0. Mean tumor size was 6.1 cm ± 1.8; all tumors were hypervascular. Patients underwent CT hepatic perfusion before and after injection of 24 µg of norepinephrine intraarterially (4 µg/mL; total 6 mL injected at a rate of 1 mL/s). Color-coded perfusion maps were used to assess the effects of local therapy on hepatic perfusion values. Tumor-to-liver ratio (TLR) was calculated from the ratio of tumor perfusion to background liver perfusion value. RESULTS: Seven of 8 patents had significant (P = .04) absolute increase in tumor perfusion vs background liver, varying from incremental (-2 mL/min/100 mL) to 290 mL/min/100 mL. There was a nonsignificant increase in TLR from 2.7 ± 1.3 to 2.9 ± 1.4 after norepinephrine injection (P = .8). Mean peak time to maximal increase in tumor perfusion after injection was 6.1 s (range, 4.5-9.1 s). Norepinephrine injection was well tolerated without major adverse events. CONCLUSIONS: Norepinephrine causes increased blood flow toward HCC tumors, but with a corresponding smaller increase in blood flow to noncancerous liver tissue, with no observed systemic side effects.

A Single-Center Experience With Percutaneous Interventional Management of Refractory Chylous Ascites.

PURPOSE: Management of chylous ascites is poorly understood with no management guidelines. We retrospectively reviewed patients treated for chylous ascites at our institution to evaluate efficacy and safety of lipiodol lymphangiography and embolization. MATERIALS AND METHODS: Seven patients underwent percutaneous interventional management of chylous ascites (average age 52.5 years, 3 female, 6 post-surgical, 1 pancreatitis) from 2012. All patients underwent lipiodol inguinal lymph node injection. Adjunctive glue embolization was performed if a leak was identified. Data were collected on the cause of chylous ascites, conservative management strategies, procedural details, and success. RESULTS: All patients had chylous ascites refractory to conservative management. Preprocedure lymphoscintigraphy identified a retroperitoneal leak in 6 patients. Seven patients underwent 12 lymphangiogram procedures; 8 were performed at our institution. Lymphangiography identified a leak in 5 patients (71%). Success was achieved in 2 patients (28%) treated at our institution after glue embolization following cannulation of the leaking lymphatic channels and 1 patient (14%) after lymphangiography alone for an overall success rate of 43% (3/7). Two patients (29%) were successfully treated after one procedure. Two patients (29%) unsuccessfully treated at our institution were referred to a specialized center in the United States. No 30 day post procedural complications. CONCLUSIONS: In our experience, lymphangiography and embolization was a safe, relatively effective and minimally invasive method for treating medically refractory chylous ascites. Complex cases required referral to a specialized institution with resources unavailable at our tertiary care center.

KDOQI Clinical Practice Guideline for Vascular Access: 2019 Update.

The National Kidney Foundation's Kidney Disease Outcomes Quality Initiative (KDOQI) has provided evidence-based guidelines for hemodialysis vascular access since 1996. Since the last update in 2006, there has been a great accumulation of new evidence and sophistication in the guidelines process. The 2019 update to the KDOQI Clinical Practice Guideline for Vascular Access is a comprehensive document intended to assist multidisciplinary practitioners care for chronic kidney disease patients and their vascular access. New topics include the end-stage kidney disease "Life-Plan" and related concepts, guidance on vascular access choice, new targets for arteriovenous access (fistulas and grafts) and central venous catheters, management of specific complications, and renewed approaches to some older topics. Appraisal of the quality of the evidence was independently conducted by using a Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach, and interpretation and application followed the GRADE Evidence to Decision frameworks. As applicable, each guideline statement is accompanied by rationale/background information, a detailed justification, monitoring and evaluation guidance, implementation considerations, special discussions, and recommendations for future research.

Drug-Coated Balloon Angioplasty in Hemodialysis Circuits: A Systematic Review and Meta-Analysis.

PURPOSE: To perform a systematic review and meta-analysis assessing patency outcomes following drug-coated balloon angioplasty (DCBA) in hemodialysis circuits. MATERIALS AND METHODS: MEDLINE and EMBASE systematic searches were performed from inception to November 2018 to identify comparative studies assessing DCBA vs plain old balloon angioplasty (POBA) in hemodialysis circuits. Abstract selection, data extraction, and quality assessment were performed by 2 independent reviewers. Primary outcome was loss of target lesion patency at 3, 6, 12, and 24 months for autogenous arteriovenous fistula (AVF), prosthetic arteriovenous graft (AVG), and hemodialysis-related central venous stenosis. RESULTS: Twelve studies comprising 908 patients were included. There was a significant improvement in patency among AVF after DCBA vs POBA at 3, 6, 12, and 24 months (odds ratio 0.58 [95% confidence interval, 0.36-0.94]; odds ratio 0.40 [95% confidence interval 0.23-0.70]; odds ratio 0.39 [95% confidence interval, 0.25-0.61]; and odds ratio 0.20 [95% confidence interval, 0.07-0.62]). This benefit persisted on subgroup analysis of randomized controlled trials (RCTs) only. Meta-analysis of results specific to AVG could not be performed, as only 1 RCT was identified that favored DCBA. Hemodialysis-associated central vein stenosis did not demonstrate a significant difference in patency rates between DCBA and POBA on meta-analysis. Twelve-month mortality and same-day complication rates did not differ between arms. CONCLUSIONS: Significant improvement in patency was identified with DCBA in AVF at 3, 6, 12, and 24 months. A single comparative study identified benefit of DCBA use in the AVG group. No significant benefit was identified with DCBA for central stenosis.

Drug-eluting balloon angioplasty versus uncoated balloon angioplasty for the treatment of in-stent restenosis of the femoropopliteal arteries.

BACKGROUND: Stents are placed in the femoropopliteal arteries for numerous reasons, such as atherosclerotic disease, the need for dissection, and perforation of the arteries, and can become stenosed with the passage of time. When a stent develops a flow-limiting stenosis, this process is known as "in-stent stenosis." It is thought that in-stent restenosis is caused by a process known as "intimal hyperplasia" rather than by the progression of atherosclerotic disease. Management of in-stent restenosis may include performing balloon angioplasty, deploying another stent within the stenosed stent to force it open, and creating a bypass to deliver blood around the stent. The role of drug-eluting technologies, such as drug-eluting balloons (DEBs), in the management of in-stent restenosis is unclear. Drug-eluting balloons might function by coating the inside of stenosed stents with cytotoxic chemicals such as paclitaxel and by inhibiting the hyperplastic processes responsible for in-stent restenosis. It is important to perform this systematic review to evaluate the efficacy of DEB because of the potential for increased expenses associated with DEBs over uncoated balloon angioplasty, also known as plain old balloon angioplasty (POBA). OBJECTIVES: To assess the safety and efficacy of DEBs compared with uncoated balloon angioplasty in people with in-stent restenosis of the femoropopliteal arteries as assessed by criteria such as amputation-free survival, vessel patency, target lesion revascularization, binary restenosis rate, and death. We define "in-stent restenosis" as 50% or greater narrowing of a previously stented vessel by duplex ultrasound or angiography. SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, and CINAHL databases and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to November 28, 2017. Review authors also undertook reference checking to identify additional studies. SELECTION CRITERIA: We included all randomized controlled trials that compared DEBs versus uncoated balloon angioplasty for treatment of in-stent restenosis in the femoropopliteal arteries. DATA COLLECTION AND ANALYSIS: Two review authors (AK, WA) independently selected appropriate trials and performed data extraction, assessment of trial quality, and data analysis. The senior review author (AD) adjudicated any disagreements. MAIN RESULTS: Three trials that randomized a combined total of 263 participants met the review inclusion criteria. All three trials examined the treatment of symptomatic in-stent restenosis within the femoropopliteal arteries. These trials were carried out in Germany and Austria and used paclitaxel as the agent in the drug-eluting balloons. Two of the three trials were industry sponsored. Two companies manufactured the drug-eluting balloons (Eurocor, Bonn, Germany; Medtronic, Fridley, Minnesota, USA). The trials examined both anatomical and clinical endpoints. We noted heterogeneity in the frequency of bailout stenting deployment between studies as well as in the dosage of paclitaxel applied by the DEBs. Using GRADE assessment criteria, we determined that the certainty of evidence presented was very low for the outcomes of amputation, target lesion revascularization, binary restenosis, death, and improvement of one or more Rutherford categories. Most participants were followed up to 12 months, but one trial followed participants for up to 24 months.Trial results show no difference in the incidence of amputation between DEBs and uncoated balloon angioplasty. DEBs showed better outcomes for up to 24 months for target lesion revascularization (odds ratio (OR) 0.05, 95% confidence Interval (CI) 0.00 to 0.92 at six months; OR 0.24, 95% CI 0.08 to 0.70 at 24 months) and at six and 12 months for binary restenosis (OR 0.28, 95% CI 0.14 to 0.56 at six months; OR 0.34, 95% CI 0.15 to 0.76 at 12 months). Participants treated with DEBs also showed improvement of one or more Rutherford categories at six and 12 months (OR 1.81, 95% CI 1.02 to 3.21 at six months; OR 2.08, 95% CI 1.13 to 3.83 at 12 months). Data show no clear differences in death between DEBs and uncoated balloon angioplasty. Data were insufficient for subgroup or sensitivity analyses to be conducted. AUTHORS' CONCLUSIONS: Based on a meta-analysis of three trials with 263 participants, evidence suggests an advantage for DEBs compared with uncoated balloon angioplasty for anatomical endpoints such as target lesion revascularization (TLR) and binary restenosis, and for one clinical endpoint - improvement in Rutherford category post intervention for up to 24 months. However, the certainty of evidence for all these outcomes is very low due to the small number of included studies and participants and the high risk of bias in study design. Adequately powered and carefully constructed randomized controlled trials are needed to adequately investigate the role of drug-eluting technologies in the management of in-stent restenosis.

Outcomes at a single center after subintimal arterial flossing with antegrade-retrograde intervention for critical limb ischemia.

OBJECTIVE: The subintimal arterial flossing with antegrade-retrograde intervention technique has been used to overcome antegrade recanalization failures for peripheral lower limb arterial occlusive disease. There are few outcomes published for this technique and we sought to evaluate outcomes at our institution over a 7-year period. METHODS: A retrospective review was performed of all subintimal arterial flossing with antegrade-retrograde intervention procedures of infrainguinal occlusive disease from 2009 to 2016. Retrograde and antegrade accesses were combined when occlusions could not be crossed from the antegrade direction. Baseline patient characteristics, procedures, procedure time, fluoroscopy time, contrast used, and radiation dose were collected. Posterior tibial waveforms, ankle-brachial index, limb salvage, vessel patency, and the presence of symptoms were assessed at follow-up. RESULTS: Treatment was performed in 52 limbs in 52 patients (35 men and 17 women; mean age, 77.62 ± 11.61 years) with critical limb ischemia and no appropriate venous conduit for surgical bypass. Among the cohort, 63.5% were diabetics, 98% had hypertension, 53.8% had a prior myocardial infarction, and 36.5% end-stage renal disease. The average Rutherford Category before the intervention was 5.08 ± 1.01. Retrograde pedal access was most commonly obtained in the anterior tibial artery/dorsalis pedis (55.7%), followed by the posterior tibial artery (40.3%). The technical success rate was 63.5% (33/52); adjunctive stenting was needed in 19 (36.5%) to optimize results. Preprocedural ankle-brachial index score was 0.54 ± 0.25, which improved after the procedure to an ankle-brachial index score of 0.77 ± 0.25. The primary patency rates at 3 and 6 months were 65% and 60%, respectively. The limb salvage rate at a mean follow-up of 5.4 months was 78.8%. There were 5 complications; 4 were hematomas managed conservatively and 1 was a major retroperitoneal bleed resulting in patient death. CONCLUSIONS: Retrograde pedal access is a viable revascularization technique for achieving limb salvage in patients with critical limb ischemia with acceptable patency for limb-threatening ischemia. This technique expands revascularization options after failed conventional endovascular antegrade approaches.

Transabdominal Direct Sac Puncture Embolization of Type II Endoleaks after Endovascular Abdominal Aortic Aneurysm Repair.

PURPOSE: To determine the efficacy and safety of transabdominal direct sac puncture embolization of type II endoleaks after endovascular abdominal aortic aneurysm repair (EVAR). MATERIALS AND METHODS: This retrospective review included 30 patients (4 women, 26 men; mean age = 79.1 years) who underwent 33 transabdominal direct sac puncture embolization procedures for type II endoleaks after EVAR. Embolization agents included cyanoacrylate glue only (45.5%), glue/coils (36.4%), and Onyx with or without glue/coils (18.1%). Technical success was defined as complete endoleak embolization on intraprocedural fluoroscopy. The primary outcome was freedom of aneurysm growth, which was defined as ≤ 5% aneurysm sac volume change on follow-up computed tomography (CT) imaging or ≤ 5 mm aneurysm sac diameter change on ultrasound without definite endoflow. Aneurysm sac volumes before and after embolization were manually segmented from CT images. The procedural complication rate was calculated. RESULTS: Technical success was achieved in 97% of patients (29/30). Follow-up imaging was available in 27 patients (25 CT; 2 ultrasound), and mean imaging follow-up duration was 15.5 months. Freedom of aneurysm growth was achieved in 85.2% of patients (23/27) after 1 or more embolization procedures. Median fluoroscopic and procedure times were 11.3 minutes and 90 minutes, respectively. The complication rate was 9.1% (3/33) and included 1 case of nontarget embolization with transient neuropraxia and 2 self-limiting rectus sheath hematomas relating to the percutaneous puncture site. No aneurysm-related mortality occurred during the follow-up period. CONCLUSIONS: Percutaneous transabdominal embolization is a safe and efficacious treatment for type II endoleak, with a short procedure time.

Comparison between Surgical and Endovascular Hemodialysis Arteriovenous Fistula Interventions and Associated Costs.

PURPOSE: To compare: (i) rate of arteriovenous fistula (AVF) interventions in both incident and prevalent end-stage kidney disease patients; (ii) their associated costs; and (iii) intervention-free survival between patients with surgical hemodialysis arteriovenous fistula (SAVF) versus those with an endovascularly created fistula (endoAVF). MATERIALS AND METHODS: Data from the United States Renal Data System (USRDS) were abstracted to determine the rate of AVF interventions performed in the first year and associated costs (based on Medicare payment rates) for SAVFs created from 2011 to 2013 in the incident and prevalent patient cohorts. Comparative data for endoAVF were obtained from the Novel Endovascular Access Trial (NEAT). Event rates, intervention-free survival, and costs were compared between endoAVF and SAVF cohorts after 1:1 propensity score (PS) matching. RESULTS: In the matched incident patients, the event rate was 0.74 per patient-year (PY) for endoAVF versus 7.22/PY for SAVF (P < .0001), with a difference in expenditures of $16,494. Similarly, in matched prevalent patients the event rate was 0.46/PY for endoAVF vs 4.10/PY for SAVF (P < .0001), resulting in a cost difference of $13,389. Time-to-event analysis showed that at 1 year, 70% of endoAVF patients experienced freedom from intervention versus only 18% of SAVF patients for incident patients; these numbers were 62% and 18% for endoAVF and SAVF prevalent patients, respectively (P < .0001 for both). CONCLUSIONS: Both incident and prevalent patients with endoAVF required fewer interventions and had lower costs within the first year compared with matched patients with SAVF.

Financial Impact of PEVAR Compared With Standard Endovascular Repair in Canadian Hospitals.

OBJECTIVES: The percutaneous endovascular abdominal aortic repair (PEVAR) approach is a minimally invasive technique that has demonstrated clinical benefit over traditional surgical cut down associated with standard endovascular abdominal aortic aneurysm (AAA) repair (EVAR). The objective of our study was to evaluate the budget impact to a Canadian hospital of changing the technique for AAA repair from the EVAR approach to the PEVAR approach. METHODS: We examined the budget impact of replacing the EVAR approach with the PEVAR approach in a Canadian hospital that performs 100 endovascular AAA repairs annually. The model incorporates the costs associated with surgery, length of stay, and postoperative complications occurring within 30 days. RESULTS: The use of PEVAR in AAA repair is associated with increased access device costs when compared with the EVAR approach (CAD$1000 vs CAD$400). However, AAA repair completed with the PEVAR approach demonstrates reduced operating time (101 minutes vs 133 minutes), length of stay (2.2 days vs 3.5 days), time in the recovery room (174 minutes vs 193 minutes), and postoperative complications (6% vs 30%), which offset the increased device costs. The model establishes that switching to the PEVAR approach in a Canadian hospital performing 100 AAA repairs annually would result in a potential cost avoidance of CAD$245,120. CONCLUSIONS: A change in AAA repair technique from EVAR to PEVAR can be a cost-effective solution for Canadian hospitals.

Endovascular Proximal Forearm Arteriovenous Fistula for Hemodialysis Access: Results of the Prospective, Multicenter Novel Endovascular Access Trial (NEAT).

BACKGROUND: Hemodialysis arteriovenous fistulas (AVFs) are suboptimally used primarily due to problems with maturation, early thrombosis, and patient nonacceptance. An endovascular approach to fistula creation without open surgery offers another hemodialysis vascular access option. STUDY DESIGN: Prospective, single-arm, multicenter study (Novel Endovascular Access Trial [NEAT]). SETTINGS & PARTICIPANTS: Consecutive adult non-dialysis-dependent and dialysis-dependent patients referred for vascular access creation at 9 centers in Canada, Australia, and New Zealand. INTERVENTION: Using catheter-based endovascular technology and radiofrequency energy, an anastomosis was created between target vessels, resulting in an endovascular AVF (endoAVF). OUTCOMES: Safety, efficacy, functional usability, and patency end points. MEASUREMENTS: Safety as percentage of device-related serious adverse events; efficacy as percentage of endoAVFs physiologically suitable (brachial artery flow ≥ 500mL/min, vein diameter ≥ 4mm) for dialysis within 3 months; functional usability of endoAVFs to provide prescribed dialysis via 2-needle cannulation; primary and cumulative endoAVF patencies per standardized definitions. RESULTS: 80 patients were enrolled (20 roll-in and 60 participants in the full analysis set; the latter are reported). EndoAVFs were created in 98% of participants; 8% had a serious procedure-related adverse event (2% device related). 87% were physiologically suitable for dialysis (eg, mean brachial artery flow, 918mL/min; endoAVF vein diameter, 5.2mm [cephalic vein]). EndoAVF functional usability was 64% in participants who received dialysis. 12-month primary and cumulative patencies were 69% and 84%, respectively. LIMITATIONS: Due to the unique anatomy and vessels used to create endoAVFs, this was a single-arm study without a surgical comparator. CONCLUSIONS: An endoAVF can be reliably created using a radiofrequency magnetic catheter-based system, without open surgery and with minimal complications. The endoAVF can be successfully used for hemodialysis and demonstrated high 12-month cumulative patencies. It may be a viable alternative option for achieving AVFs for hemodialysis patients in need of vascular access.