Two-Year Results of a First-In-Human Study in Patients Surgically Implanted With a Bioprosthetic Venous Valve, the VenoValve in Patients With Severe Chronic Venous Insufficiency.

OBJECTIVE: Two-year follow-up results from a first-in-human study of patients implanted with the VenoValve are evaluated for supporting the long-term clinical safety and performance of the device. BACKGROUND: Chronic Venous Insufficiency (CVI) involves improper functioning of lower limb vein valves and inability of these valves to move blood back towards the heart. CVI symptoms include swelling, varicose veins, pain, and leg ulcers. Currently, there is no cure for this condition and treatment options are limited. This study provides 2-year outcomes for 8 patients who were implanted with the bioprosthetic VenoValve for treating severe CVI with deep venous reflux measured at the mid-popliteal vein. The 6-month and 1-year results were previously published. METHODS: Eleven patients with C5 & C6 CVI were implanted with VenoValve into the midthigh femoral vein and followed for 2 years. Assessed clinical outcomes include device-related adverse events, reflux time, disease severity, and pain scores. RESULTS: All 11 implant procedures were successful. Two-year follow-up data was obtained for 8 subjects: 1 patient died of non-device related causes, 1 was lost to follow-up, and 1 refused to follow-up due to the COVID-19 pandemic. No device-related adverse events occurred between the first and second years of follow-up. Reported 2-year clinical performance outcomes included significant decreases in mean reflux times of the mid-popliteal vein (61%), and significant improvements in mean scores for disease severity rVCSS (56%) and VAS pain (87%). CONCLUSIONS: Results from this study support long-term safety and effectiveness of the VenoValve for improving CVI severity by reducing reflux and thereby venous pressures in the lower extremities. With limited treatments for valvular incompetence involved in severe, deep venous CVI, the device may be considered as a novel therapy. A pivotal trial in the United States is currently being conducted to assess the device in a larger number of patients.

One-Year First-in-Human Success for VenoValve in Treating Patients With Severe Deep Venous Insufficiency.

OBJECTIVE: The clinical outcomes of this first-in-human (FIH) study provide safety and performance results 1 year after implantation of the VenoValve. BACKGROUND: Chronic venous insufficiency (CVI) is most often caused by valve failure in the venous system, which circulates blood from the lower limbs back to the heart and lungs. Severe diseases significantly influence quality of life, and current treatment options are limited. This study provides 1-year patient outcomes from 11 patients implanted with the VenoValve for treatment of severe deep venous CVI in C5 and C6 patients. Earlier results from 6-month follow-ups were previously published. METHODS: This prospective FIH study assessed the safety and performance of the VenoValve surgically implanted in 11 patients with C5 and C6 disease. All patients were followed up for at least 1 year. Assessments for adverse events, reflux time, disease severity, pain scores, and quality of life were reported. RESULTS: Implantation of VenoValve into the deep femoral vein was successful in all patients. Adverse events included 1 hematoma, 3 superficial wound infections, and 1 bleeding complication due to over-anticoagulation. One VenoValve became occluded due to patient non-compliance with anticoagulation medication. One-year clinical outcomes included significant decreases in mean reflux times (54%), and significant improvements in mean disease severity revised venous clinical severity score (56%), mean visual analog scale pain scores (76%), and Venous Insufficiency Epidemiologic and Economic Study QOL/sym scores. CONCLUSIONS: The promising results from this FIH study demonstrate sustained safety and effectiveness of the VenoValve at 1 year post-implantation, and support further study for its use as a novel treatment for severe, deep venous CVI caused by valvular incompetence. A pivotal, prospective, non-blinded, single-arm, multi-center study in the United States with seventy-five (75) patients is in progress to assess the safety and effectiveness of VenoValve in these patients through 30 days and 6 months. The clinical trial is registered on ClinicalTrials.gov under identifier: NCT04943172 (https://clinicaltrials.gov/ct2/show/NCT04943172?term=hancock+jaffe&draw=2&rank=1).

Human trial using the novel bioprosthetic VenoValve in patients with chronic venous insufficiency.

BACKGROUND: Chronic venous insufficiency (CVI) is a disease characterized by failure of the venous valves that allow blood from the lower limbs to return to the heart. The more severe types of CVI (C4b-C6 disease) significantly influence patients' quality of life (QOL). The treatment options for CVI of the deep system are limited. The present study is the first-in-human study using a prosthetic venous valve, VenoValve, to initially evaluate patient outcomes. We evaluated the feasibility, initial safety, and performance outcomes of the VenoValve. METHODS: Ten patients with C5-C6 CVI of the deep venous system secondary to postthrombotic syndrome had had a VenoValve surgically implanted into the femoral vein in Bogota, Colombia, under approval of the local ethics committee and Colombian National Food and Drug Surveillance Institute, national health care regulatory body, or the Colombian National Food and Drug Surveillance Agency. Follow-up examinations were conducted postoperatively at 2 and 14 days and then every 30 days for 6 months. The results of the assessments for adverse events, reflux time, disease severity (venous clinical severity scores), pain scores (visual analog scale), and QOL (VEINES-QOL/Sym [venous insufficiency epidemiological and economic study-QOL/symptoms] questionnaire) were documented. RESULTS: Ten patients underwent successful implantation of the VenoValve into the femoral vein as outpatients (100% technical success rate). Of the 10 patients, 9 had undergone VenoValve placement under regional anesthesia and 1 under local anesthesia. Six patients had required bovine patch angioplasty of the vein. Four adverse events occurred, including one case of hematoma at the incision site that was aspirated, 2 cases of superficial wound infection in C6 patients treated with antibiotics, and 1 case of a bleeding complication due to warfarin anticoagulation. One patient's VenoValve had thrombosed at 5 months due to nontherapeutic anticoagulation. Improvements in all 5 patients who had reached the 6-month follow-up mark with the VenoValve were demonstrated during the study period by decreases in the venous clinical severity scores (61% decrease from baseline), visual analog scale for pain scores (57% decrease), and reflux time (40% decrease) and a statistically significant improvement in the VEINES-QOL/Sym questionnaire. The patient with the occluded VenoValve had experienced improvements in all areas except for the reflux time. The latter patient had shown improvement because her ulcer had nearly healed before the occurrence of the thrombosis. CONCLUSIONS: The early results of the first-in-human trial using the VenoValve appear promising, with improvements in clinical outcomes and QOL. The VenoValve is the first prosthetic valve that has shown success at 6 months of follow-up. These findings offer insight for creating better outcomes for these highly disabled patients.

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.

KDOQI Clinical Practice Guideline for vascular access: 2019 update

The National Kidney Foundation's Kidney Disease Outcomes Quality Initiative (KDOQI) has provided evidencebased 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

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.

Medicare Costs Associated With Arteriovenous Fistulas Among US Hemodialysis Patients.

BACKGROUND: An arteriovenous fistula (AVF) is the recommended vascular access for hemodialysis (HD). Previous studies have not examined the resources and costs associated with creating and maintaining AVFs. STUDY DESIGN: Retrospective observational study. SETTING & PARTICIPANTS: Elderly US Medicare patients initiating hemodialysis therapy during 2010 to 2011. PREDICTOR: AVF primary and secondary patency and nonuse in the first year following AVF creation. OUTCOMES: Annualized vascular access costs per patient per year. RESULTS: Among patients with only a catheter at HD therapy initiation, only 54% of AVFs were successfully used for HD, 10% were used but experienced secondary patency loss within 1 year of creation, and 83% experienced primary patency loss within 1 year of creation. Mean vascular access costs per patient per year in the 2.5 years after AVF creation were $7,871 for AVFs that maintained primary patency in year 1, $13,282 for AVFs that experienced primary patency loss in year 1, $17,808 for AVFs that experienced secondary patency loss in year 1, and $31,630 for AVFs that were not used. Similar patterns were seen among patients with a mature AVF at HD therapy initiation and patients with a catheter and maturing AVF at HD therapy initiation. Overall, in 2013, fee-for-service Medicare paid $2.8 billion for dialysis vascular access-related services, ∼12% of all end-stage renal disease payments. LIMITATIONS: Lack of granularity with certain billing codes. CONCLUSIONS: AVF failure in the first year after creation is common and results in substantially higher health care costs. Compared with patients whose AVFs maintained primary patency, vascular access costs were 2 to 3 times higher for patients whose AVFs experienced primary or secondary patency loss and 4 times higher for patients who never used their AVFs. There is a need to improve AVF outcomes and reduce costs after AVF creation.

Definitions and End Points for Interventional Studies for Arteriovenous Dialysis Access.

This paper is part of the Clinical Trial Endpoints for Dialysis Vascular Access Project of the American Society of Nephrology Kidney Health Initiative. The purpose of this project is to promote research in vascular access by clarifying trial end points which would be best suited to inform decisions in those situations in which supportive clinical data are required. The focus of a portion of the project is directed toward arteriovenous access. There is a potential for interventional studies to be directed toward any of the events that may be associated with an arteriovenous access' evolution throughout its life cycle, which has been divided into five distinct phases. Each one of these has the potential for relatively unique problems. The first three of these correspond to three distinct stages of arteriovenous access development, each one of which has been characterized by objective direct and/or indirect criteria. These are characterized as: stage 1-patent arteriovenous access, stage 2-physiologically mature arteriovenous access, and stage 3-clinically functional arteriovenous access. Once the requirements of a stage 3-clinically functional arteriovenous access have been met, the fourth phase of its life cycle begins. This is the phase of sustained clinical use from which the arteriovenous access may move back and forth between it and the fifth phase, dysfunction. From this phase of its life cycle, the arteriovenous access requires a maintenance procedure to preserve or restore sustained clinical use. Using these definitions, clinical trial end points appropriate to the various phases that characterize the evolution of the arteriovenous access life cycle have been identified. It is anticipated that by using these definitions and potential end points, clinical trials can be designed that more closely correlate with the goals of the intervention and provide appropriate supportive data for clinical, regulatory, and coverage decisions.

Comparison of post-creation procedures and costs between surgical and an endovascular approach to arteriovenous fistula creation.

INTRODUCTION: Due to early and late failures that may occur with surgically created hemodialysis arteriovenous fistulas (SAVF), post-creation procedures are commonly required to facilitate AVF maturation and maintain patency. This study compared AVF post-creation procedures and their associated costs in patients with SAVF to patients with a new endovascularly created AVF (endoAVF). METHODS: A 5% random sample from Medicare Standard Analytical Files was abstracted to determine post-creation procedures and associated costs for SAVF created from 2011 to 2013. Medicare enrollment during the 6 months prior to and after the AVF creation was required. Patients' follow-up inpatient, outpatient, and physician claims were used to identify post-creation procedures and to estimate average procedure costs. Comparative procedural information on endoAVF was obtained from the Novel Endovascular Access Trial (NEAT). RESULTS: Of 3764 Medicare SAVF patients, 60 successfully matched to endoAVF patients using 1:1 propensity score matching of baseline demographic and clinical characteristics. The total post-creation procedural event rate within 1 year was lower for endoAVF patients (0.59 per patient-year) compared to the matched SAVF cohort (3.43 per patient-year; p<0.05). In the endoAVF cohort, event rates of angioplasty, thrombectomy, revision, catheter placement, subsequent arteriovenous graft (AVG), new SAVF, and vascular access-related infection were all significantly lower than in the SAVF cohort. The average first year cost per patient-year associated with post-creation procedures was estimated at US$11,240 USD lower for endoAVF than for SAVF. CONCLUSIONS: Compared to patients with SAVF, patients with endoAVF required fewer post-creation procedures and had lower associated mean costs within the first year.

Drug eluting grafts for hemodialysis access.

The development of new methods for drug elution of graft material, biofiber films and resurfacing of prosthetic graft surfaces offers new opportunities for improvement of graft function in arteriovenous (AV) access. Three areas of research include developing grafts that reduce the development of neointimal hyperplasia, reducing infection and reducing thrombogenicity. The only drug eluting graft presently being used, is the heparin coated expanded polytetrafluoroethylene (ePTFE) graft, which has been shown to decrease the incidence of early thrombosis. New drug eluting grafts include those with paclitaxel and those with antibiotics. The development of a hybrid coated prosthetic graft that can deliver targeted gene therapies holds great promise in the field.

Optiflow anastomotic device for hemodialysis vascular access creation.

The need to have consistent methods and consistent technique to optimize hemodialysis outcomes is behind the concept of the Optiflow™ device. This device was created to allow for consistency in size of the arterial anastomosis and consistency in angle of the vein to the artery at the anastomosis. Early data suggest that allowing these two technical entities can improve outcomes in regards to flow and maturity in arteriovenous fistula creation. This article is a summary of early data that demonstrate the impact the Optiflow device on brachial cephalic fistulas.

Bioengineered human acellular vessels for dialysis access in patients with end-stage renal disease: two phase 2 single-arm trials.

BACKGROUND: For patients with end-stage renal disease who are not candidates for fistula, dialysis access grafts are the best option for chronic haemodialysis. However, polytetrafluoroethylene arteriovenous grafts are prone to thrombosis, infection, and intimal hyperplasia at the venous anastomosis. We developed and tested a bioengineered human acellular vessel as a potential solution to these limitations in dialysis access. METHODS: We did two single-arm phase 2 trials at six centres in the USA and Poland. We enrolled adults with end-stage renal disease. A novel bioengineered human acellular vessel was implanted into the arms of patients for haemodialysis access. Primary endpoints were safety (freedom from immune response or infection, aneurysm, or mechanical failure, and incidence of adverse events), and efficacy as assessed by primary, primary assisted, and secondary patencies at 6 months. All patients were followed up for at least 1 year, or had a censoring event. These trials are registered with ClinicalTrials.gov, NCT01744418 and NCT01840956. FINDINGS: Human acellular vessels were implanted into 60 patients. Mean follow-up was 16 months (SD 7·6). One vessel became infected during 82 patient-years of follow-up. The vessels had no dilatation and rarely had post-cannulation bleeding. At 6 months, 63% (95% CI 47-72) of patients had primary patency, 73% (57-81) had primary assisted patency, and 97% (85-98) had secondary patency, with most loss of primary patency because of thrombosis. At 12 months, 28% (17-40) had primary patency, 38% (26-51) had primary assisted patency, and 89% (74-93) had secondary patency. INTERPRETATION: Bioengineered human acellular vessels seem to provide safe and functional haemodialysis access, and warrant further study in randomised controlled trials. FUNDING: Humacyte and US National Institutes of Health.

HeRO graft versus lower extremity grafts in hemodialysis patients with long standing renal failure.

BACKGROUND: The role of the HeRO graft in central venous pathology has been defined in the literature and clinically. There have been two publications or abstracts that have compared the patency rates and outcomes of this graft to the lower extremity graft. AIM: The outcomes of both publications leads to an algorithm suggested by the author in determining which procedure should be used for specific patients. METHODS: Both papers trend to show that lower extremity grafts have improved patency rates when compared to the HeRO device in the upper extremity. DISCUSSION: The author will use these data to demonstrate that in younger patients and in patients with low morbidity and mortality, salvaging the upper extremity area for access may show that the HeRO device provides benefit for these patients.

Early cannulation graft: Acuseal.

AIM: To review the published literature on the early cannulation graft, Acuseal. METHODS: 235 reported cases have been published and reviewed. These cases are both prospective and retrospective, from either multicenter or single centers. Patency rates and complication rates were reviewed. Economic value of early cannulation grafts were also analyzed. RESULTS: Over 135 patients were cannulated within 2.5 days after implantation. No increase in complications were noted and similar primary and secondary patency rates were observed compared to the literature. Economic evaluation both in the UK and US demonstrate benefit of this graft when compared to catheters, fistulas and other grafts. CONCLUSION: Early stick grafts demonstrate similar patency and complication rates when compared to published literature of standard grafts.Economic benefit is also noted using this graft.

Prospective multicenter study with a 1-year analysis of a new vascular graft used for early cannulation in patients undergoing hemodialysis.

OBJECTIVE: More than 85% of patients with end-stage renal disease start dialysis through a tunneled dialysis catheter (TDC) for long periods while their arteriovenous fistula or vascular access graft (arteriovenous graft [AVG]) matures. Because TDCs are associated with a high risk of complications, including death and infection, use of an AVG that can be cannulated safely immediately after implantation may reduce morbidity in these patients by allowing earlier TDC removal. We report a prospective multicenter study of a new early-cannulation AVG (Gore ACUSEAL Vascular Graft; W. L. Gore & Associates, Flagstaff, Ariz). METHODS: Patients requiring creation of a prosthetic vascular access for hemodialysis were enrolled between July 2010 and February 2012 and observed for 12 months. Data were collected on the patients' baseline characteristics; location, position, loss of patency, and revisions of prior AVGs; dialysis sessions using the AVG; and major adverse events related to graft implantation or cannulation. Cumulative and primary unassisted graft patency rates were calculated. A subgroup analysis compared outcomes in patients in whom the AVG was first cannulated within 72 hours after implantation with outcomes in patients in whom the initial cannulation was performed >21 days postoperatively. RESULTS: The population of this study was formed by 138 patients who received an ACUSEAL graft. During follow-up, 17 patients died and the AVG was abandoned in 27. The median value for follow-up was 360 days for all patients (variance 15,387). The overall mean time to initial cannulation was 15 days, with 54 grafts (40%) first cannulated within 72 hours after graft implantation and 33 grafts first cannulated >21 days afterward. The reason for late cannulation in some patients was dependent on the implanting surgeon's decision and the surgeon's personal experience with early cannulating grafts. The 1-year overall cumulative patency rate was 79% (95% confidence interval, 71%-85%); the primary unassisted patency rate was 35% (95% confidence interval, 27%-44%). Adverse events included 6 hematomas (two of which were related to cannulation and occurred 107 and 169 days, respectively, after AVG implantation), 15 graft infections, and 15 cases of steal syndrome requiring intervention. Patients in the early- and later-cannulation groups had similar characteristics and no significant differences in rates of cumulative or primary unassisted patency or adverse events. CONCLUSIONS: This study demonstrated that the new, early-cannulation AVG graft can be cannulated soon after implantation without a significant difference in patency and complication rates compared with rates associated with standard cannulation of expanded polytetrafluoroethylene grafts in the literature. This new AVG may allow early removal or avoidance of TDC use in patients undergoing hemodialysis, potentially reducing or eliminating the number of days of catheter-dependent dialysis, but further studies will be needed to demonstrate this potential.

Arteriovenous graft configuration in hemodialysis: does it matter?

PURPOSE: The current guidelines for arteriovenous graft (AVG) configuration in hemodialysis state the following sequence: forearm loop, upper arm straight or curved and upper arm looped. These recommendations are based upon literature from the 1980s. Modern patient demographics and patient treatment algorithms, i.e., the Fistula First initiative (FFI), have greatly changed the current practice environment. It is not clear if these changes alter the outcomes of AVGs based upon configuration. METHODS: The most recent National Kidney Foundation Kidney Disease Outcomes Quality Initiative (NKF/K-DOQI) guidelines for vascular access were reviewed. Articles cited to support recommendations for AVG configuration were evaluated. The following search terms: arteriovenous graft configuration, access configuration, PTFE configuration in hemodialysis and straight, looped, curved graft configuration were used to search PubMed, Ovid, Medline and Google scholar. Articles that included data comparing AVG configuration were included. Citations within those articles were examined for publications overlooked in the initial search. Four articles and one abstract were reviewed and separated into pre- and post-FFI groups. RESULTS: Pre-FFI articles demonstrate superiority of forearm looped AVG over straight forearm grafts. Post-FFI, the literature suggests that primary patency, thrombosis and steal are not affected by configuration and location, although looped configuration may have superior secondary patency. CONCLUSIONS: The available literature is mixed regarding the effect of configuration on AVG outcomes. Current studies illustrate the effect may be limited and that larger randomized controlled trials are necessary to draw firm conclusions. Regardless, adequate inflow and an appropriately sized outflow vein are paramount for optimal graft performance.

Patient compliance limits the efforts of quality improvement initiatives on arteriovenous fistula maturation.

OBJECTIVE: Our institutional quality-improvement (QI) initiative instituted a well-defined office follow-up schedule after arteriovenous fistula (AVF) creation, including an office visit within 30 days, fistulogram within 40 days, if indicated, and a second office visit within 55 days. In addition, a patient liaison contacted patients and dialysis units to improve follow-up. The purpose of this study was to determine the effect of the QI initiative on patient compliance and overall time to AVF permission to cannulate. METHODS: We performed a retrospective review of patients undergoing first-time radiocephalic, brachiocephalic, and basilic vein transposition creation before the QI initiative (pre-QI group: January to April 2012) and during the QI period (QI group: January to April 2013). Categoric data were compared using χ(2) analysis, and nominal data were compared using the Student t-test. RESULTS: We reviewed 198 first-time AVF creations in patients (57% male) with a mean age of 61 years. Demographics and comorbidities between the pre-QI and QI groups were similar. Compliance with the first 30-day postoperative appointment increased significantly after the QI initiative, from 48% in the pre-QI group to 65% in the QI group (P = .015). Yet, the QI initiative did not maintain an effect on the subsequent follow-up checkpoints. No statistical difference was identified for compliance with fistulogram within 40 days of access creation (pre-QI, 12% vs QI, 25%; P = .093) or for compliance with the 55-day postoperative appointment (pre-QI, 33% vs QI, 23%; P = .457). Both checkpoints demonstrated a very high noncompliance rate. Accordingly, the mean time to permission to cannulate was 88 days for both the pre-QI and QI groups, with a failure to mature rate of 22% for the pre-QI group and 21% for the QI group (P = .816). CONCLUSIONS: The QI initiative significantly increased the number of patients complying with the first 30-day follow-up appointment after AVF access creation. However, patient compliance with a timely fistulogram and the second follow-up appointment was poor and not influenced by the QI initiative, limiting the functional effect of the QI initiative on the time to AVF permission to cannulate.

Outcome of the pivotal study of the Aptus endovascular abdominal aortic aneurysms repair system.

OBJECTIVE: Endovascular treatment of abdominal aortic aneurysm (AAA) is associated with benefits over open surgery, yet limitations remain with current endovascular devices. This study was performed to assess outcomes of AAA repair with the Aptus endograft and EndoAnchors (Aptus Endosystems, Sunnyvale, Calif). METHODS: This prospective, multicenter, single-arm investigational device exemption trial was conducted at 25 sites in the United States. A total of 155 patients were enrolled in the trial (mean age, 73 ± 8 years; male, 93.5%; mean AAA diameter, 53.6 ± 7.9 mm). The Aptus endograft is a two-component system: a multilumen, modular endograft with two docking limbs (Aptus Endograft System) and the Heli-FX Aortic Securement System comprising an electronically controlled applier (Heli-FX Applier) with helical EndoAnchors provided in a cassette and a deflectable sheath (Heli-FX Guide) designed for delivery of the applier to the target location for EndoAnchor implantation. The main eligibility criteria included proximal neck length of ≥12 mm, diameter of 19 to 29 mm, and infrarenal angulation of ≤60 degrees. The primary safety end point was freedom from major adverse events at 30 days, and the primary effectiveness end point was successful aneurysm treatment at 12 months. Thrombus-related events (TRE) were defined as limb occlusion or thromboembolism from the endograft. Subjects were observed for a median of 4.2 years, with imaging end points analyzed by a core laboratory and adverse events adjudicated by a clinical events committee. RESULTS: Among 155 enrolled subjects, 153 (98.7%) underwent successful implantation of the Aptus endograft and a median of five EndoAnchors; two subjects were converted to open surgical repair during the initial procedure. Overall, the primary safety and effectiveness end points were met in 98.1% and 97.4% of the subjects, respectively. Aneurysm-related mortality was 0.6%, with one postdischarge cardiac death 18 days after implantation. There were no AAA ruptures. There were no fractures of stents or EndoAnchors. There was one type I endoleak and one type III endoleak. Stent graft migration was noted in five subjects, none associated with sac enlargement, type I endoleak, or EndoAnchor dislocation from the endograft. AAA sac shrinkage of ≥5 mm at 1, 2, and 3 years was observed in 60.3%, 72.9%, and 81.7%, respectively. Sixty-one subjects (39.4%) experienced 113 TRE, associated with 80 reinterventions (in 58 subjects) unassociated with limb loss or death. A root cause analysis of TRE identified small, out-of-specification docking limbs with graft infolding and high local shear, resulting in thrombus formation within the endograft with subsequent distal embolization in some cases. CONCLUSIONS: Early results of the Aptus endograft trial met its safety and effectiveness end points; however, a high rate of TRE was observed because of manufacturing discrepancies. The findings confirm a low rate of type I and type III endoleaks, migration, and non-TRE reintervention with a high rate of aneurysm sac regression during midterm follow-up.

The Venous Window Needle Guide, a hemodialysis cannulation device for salvage of uncannulatable arteriovenous fistulas.

BACKGROUND: Arteriovenous fistulas (AVFs) are recommended for hemodialysis access when possible. A noncannulatable but otherwise well functioning AVF leads to prolonged catheter dependency and frustration for the patient and the renal health care provider team. Difficult cannulation patients include obese individuals in whom cannulation sites are too deep, and others with vein segments that are short, tortuous, or otherwise difficult to palpate. The Venous Window Needle Guide for Salvage of AV Fistulae (SAVE) trial was designed to evaluate the efficacy and safety of the Venous Window Needle Guide (VWING; Vital Access Corp, Salt Lake City, Utah) device for salvage of such noncannulatable AVFs that are otherwise functional. METHODS: The SAVE study included patients with an established and otherwise mature AVF, in whom an additional procedure would otherwise be necessary to establish reliable cannulation. The VWING is a single-piece titanium device that allows repeated access of an AVF through a single puncture site (buttonhole technique). Inclusion criteria included mature AVFs 6.0 to 15.0 mm in depth with multiple failed attempts at cannulation or where the access could not be palpated. The devices were implanted subcutaneously and sutured to the anterior wall of the mature fistula. Study end points were reliable and successful cannulation and avoidance of adverse events during the 6-month follow-up, implant technical success, and clinical cannulation success. RESULTS: Enrollment included 54 patients at 11 trial sites with implantation of 82 VWING devices. Body mass index was 26 to 50 (median, 36), 40 (74%) patients were female, and age was 17 to 84 (median, 59) years. Forty (74%) individuals were diabetic. Thirty-three (61%) patients were white, 16 (30%) black, and 10 (18%) patients were Hispanic, Pacific Islander, or Native American. Three patients were excluded from data analysis for reasons unrelated to the device. Successful AVF access was achieved using the VWING in 49 (96%) of the 51 patients evaluated. The rate of device-related serious adverse events was 0.31 per patient-year; each event was resolved leaving the AVF functional. The rates of sepsis and study-related interventions were 0.04 and 0.65 per patient-year, respectively. There were no study-related deaths. One device was removed because of infection. The AVF survival rate at 6 months was 100%. The total number of study days was 9497 and the estimated number of device cannulations was 4238. CONCLUSIONS: The VWING was safe and effective in facilitating AVF cannulation for patients with an otherwise mature but noncannulatable fistula. Successful AVF access was achieved using the VWING in 49 (96%) of the 51 patients evaluated. The AVF survival rate at 6 months was 100%.

Basilic vein transposition: review of different techniques.

This is a review of the basilic vein procedure and changes that have evolved to improve outcomes. This includes reviewing data on the one-stage vs. two-stage technique as well as elevation for the basilic vein. The review discusses data that help the surgeon decide which technique he should evaluate.