Project description:In an incident hemodialysis (HD) population, we aimed to investigate whether arteriovenous fistula (AVF) creation before HD initiation was associated with improved AVF patency compared with AVF creation from a central venous catheter (CVC), and also to compare patient survival between these patients. Between January 2011 and December 2013, 524 incident HD patients with identified first predialysis vascular access with an AVF (pre-HD group, n = 191) or an AVF from a CVC (on-HD group, n = 333) were included and analyzed retrospectively. The study outcome was defined as AVF patency and all-cause mortality (time to death). On Kaplan-Meier survival analysis, primary and secondary AVF patency rates did not differ significantly between the two groups (P = 0.812 and P = 0.586, respectively), although the overall survival rate was significantly higher in the pre-HD group compared with the on-HD group (P = 0.013). On multivariate analysis, well-known patient factors were associated with decreased primary (older age and diabetes mellitus [DM]) and secondary (DM and peripheral arterial occlusive disease) AVF patency, whereas use of a CVC as the initial predialysis access (hazard ratios, 1.84; 95% confidence intervals, 1.20-2.75; P = 0.005) was significantly associated with worse survival in addition to well-known patient factors (older age, diabetes mellitus, and peripheral arterial occlusive disease). Worse survival in the on-HD group was likely confounded by selection bias because of the retrospective nature of our study. Therefore, the observed lower mortality associated with AVF creation before HD initiation is not fully attributable to CVC use, but rather, affected by other patient-level prognostic factors. There were no CVC-related complications in the pre-HD group, whereas 10.2% of CVC-related complications were noted in the on-HD group. In conclusion, among incident HD patients, compared with patients who underwent creation of an AVF from a CVC, initial AVF creation showed similar primary and secondary AVF patency rates, but lower mortality risk. We also observed that an initial CVC use was an independent risk factor associated with worse survival. A fistula-first strategy might be the best option for incident HD patients who are good candidates for AVF creation.
Project description:Rationale & objectiveTo facilitate the process of dialysis for patients with kidney failure, an arteriovenous fistula (AVF) is created using either a surgical or percutaneous approach. We sought to compare the efficacy and procedural outcomes in creating an AVF percutaneously using Ellipsys (Avenu Medical) or WavelinQ (Becton Dickinson Medical) with surgery in all patients with kidney failure requiring a permanent AVF for dialysis.Study designSystematic review and meta-analysis.Setting & study populationsAll patients requiring a permanent AVF for dialysis.Selection criteria for studiesWe included studies that compared either the Ellipsys device or WavelinQ directly with surgery to create an AVF for long-term dialysis.Data extractionTwo reviewers independently reviewed the studies and extracted the data. Conflicts were resolved with a discussion and approval from the senior author.Analytical approachFixed-effects or random-effects models were used to pool the fixed sizes and 95% CIs based on the level of heterogeneity.ResultsThere was no statistically significant difference observed between surgical AVF and endovascular AVF when comparing the primary outcomes of procedural success (OR = 1.44; 95% CI, 0.35, 5.88; P = 0.61; I2 = 0%), complications (OR = 0.28; 95% CI, 0.06, 1.46; P = 0.13; I2 = 69%), and the secondary outcomes of interest that included follow-up time (mean difference [MD] = -17.71; 95% CI, -189.53, 154.12; P = 0.84; I2 = 94%), failure rate (OR = 1.03; 95% CI, 0.21, 5.13; P = 0.97; I2 = 85%), and time to 2-needle cannulation (MD = -5.40; 95% CI, -38.88, 28.08; P = 0.75; I2 = 0%). However, a statistically significant difference was seen among the 2 groups for procedural time (MD = -54.25; 95% CI, -59.78, -48.71; P < 0.001; I2 = 98%), number of interventions needed to maintain patency (OR = 1.73; 95% CI, 1.22, 2.45; P < 0.01; I2 = 94%), and primary patency rate (OR = 0.34; 95% CI, 0.23,0.52; P < 0.001; I2 = 0%).LimitationsThe total number of studies included in this review was limited, with 3 of the 4 included studies being retrospective and only 1 being prospective. There was a lack of heterogeneity and randomization.ConclusionsPercutaneous fistula creation using Ellipsys or WavelinQ is a unique and safe alternative with outcomes comparable to surgery. Future studies are needed, including observational studies in current clinical practice, to evaluate the efficacy and outcomes of endovascular AVF creation in clinical populations.
Project description:Background: Data on congenital systemic arteriovenous fistulas are largely based on individual case reports. A true systemic arteriovenous fistula needs to be differentiated from other vascular malformations like capillary or venous hemangiomas, which are far more common. Objectives: We sought to identify the varied symptoms, diagnostic challenges, describe interventional treatment options, and postulate an embryological basis for this uncommonly described entity. Methods: This is a descriptive study of a cohort of systemic arteriovenous fistulas seen in the department of pediatric cardiology at a tertiary cardiac institute from 2010 to 2020, with prospective medium-term follow-up. A total of seven cases were identified. The diagnosis was confirmed by computed tomographic imaging, magnetic resonance angiography, or conventional angiography. Results: All were successfully closed using duct occluders or embolization coils with no recurrence in six cases over a median duration of follow-up of 48 months (interquartile range: 16; 36–52 months). Four of the seven cases underwent follow-up imaging using echocardiography or ultrasound. Conclusion: The incidence of congenital systemic arteriovenous fistulas is low and accounted for 0.009% of pediatric outpatients seen over 10 years at our institute. The spectrum of clinical presentation varies from an innocuous swelling or a pulsating mass to frank heart failure. Strong clinical suspicion and advanced imaging modalities have helped identify some hitherto undescribed connections. Large malformations with multiple communications may persist or recur despite transcatheter closure.
Project description:Background and purposeSpinal arteriovenous fistulas are challenging to cure by endovascular means, with a risk of incomplete occlusion or delayed recurrence. The authors report herein their preliminary experience using the pressure cooker technique for the embolization of spinal arteriovenous fistulas.Materials and methodsFifteen patients (8 men; mean age, 60.3 years) underwent an endovascular treatment of a spinal arteriovenous fistula (12 dural spinal arteriovenous fistulas and 3 epidural spinal arteriovenous fistulas) in 2 different institutions using the pressure cooker technique. Two microcatheters could be navigated in the segmental artery in all patients using 2 guiding catheters. A proximal plug was achieved with highly concentrated cyanoacrylate ± coils. The liquid embolic agent injected to cure the fistula was diluted cyanoacrylate (n = 11) or ethylene-vinyl alcohol (n = 4). Technical and clinical complications were systematically recorded. Clinical and angiographic outcomes were systematically evaluated at follow-up.ResultsOne (6.7%) procedure-related complication was recorded, which consisted of a transient radicular deficit, related to nerve root ischemia. Clinical improvement was observed in 10/14 (71%) patients for whom clinical follow-up was available. Complete spinal arteriovenous fistula occlusion on a follow-up angiography was observed in 11/12 patients (91.7%) for whom angiographic follow-up was available. One patient (8.3%) presented with a delayed recurrence at 29 months.ConclusionsThe pressure cooker technique is feasible, with either glue or ethylene-vinyl alcohol, for the embolization of spinal arteriovenous fistulas. Our results suggest the safety and effectiveness of this technique.
Project description:ObjectiveTo assess the feasibility, efficacy, and safety of targeted embolization for cavernous sinus dural arteriovenous fistulas (CSDAVF).Materials and methodsThis retrospective study investigated patients with CSDAVF who underwent endovascular treatment at a tertiary hospital between October 1991 and March 2023. Treatment strategies were determined based on clinical symptoms and shunt characteristics. Targeted or non-targeted curative embolization was performed to achieve complete shunt occlusion. Initially, targeted embolization, selective occlusion of the shunted pouch while preserving the normal cavernous sinus lumen, was conducted, should that fail, non-targeted embolization was performed. In contrast, palliative embolization solely reduced shunt flow. Clinical signs, imaging characteristics, and outcomes were evaluated according to the agreed treatment strategy.ResultsIn total, 198 patients with CSDAVF (mean age 59.0 ± 12.1 years, 23.2% male) participated in this study. Of which, 94 patients (47.5%) were treated with targeted embolization, 75 (37.9%) with non-targeted embolization, and 29 (14.6%) with palliative treatment. For patients undergoing curative embolization, 55.7% (94/169) successfully achieved targeted embolization; this procedure was usually used to treat focal fistulas (restrictive or late-restrictive types), whereas diffuse fistulas (proliferative type) often underwent non-targeted or palliative embolization. For patients that underwent targeted embolization, the rate of complete or near-complete occlusion on immediate post-treatment digital subtraction angiography was 93.6% (88/94), with a complication rate of 2.1% (2/94), symptom improvement rate of 96.8% (91/94), and retreatment rate of 5.3% (5/94). No serious complications were reported during follow-up.ConclusionWhen successful, targeted embolization of CSDAVF causes low rates of cranial nerve palsy, retreatment, and good clinical outcomes.
Project description:Few studies have discussed the disease nature and treatment outcomes for bilateral cavernous sinus dural arteriovenous fistula (CSDAVF). This study aimed to investigate the clinical features and treatment outcomes of bilateral CSDAVF. Embase, Medline, and Cochrane library were searched for studies that specified the outcomes of bilateral CSDAVF from inception to April 2022. The classification, clinical presentation, angiographic feature, surgical approach, and treatment outcomes were collected. Meta-analysis was performed using the random effects model. Eight studies reporting 97 patients were included. The clinical presentation was mainly orbital (n = 80), cavernous (n = 52) and cerebral (n = 5) symptoms. The most approached surgical route was inferior petrosal sinus (n = 80), followed by superior orbital vein (n = 10), and alternative approach (n = 7). Clinical symptoms of 88% of the patients (95% CI 80-93%, I2 = 0%) were cured, and 82% (95% CI 70-90%, I2 = 7%) had angiographic complete obliteration of fistulas during follow up. The overall complication rate was 18% (95% CI 11-27%, I2 = 0%). Therefore, endovascular treatment is an effective treatment for bilateral CSDAVF regarding clinical or angiographic outcomes. However, detailed evaluation of preoperative images and comprehensive surgical planning of the approach route are mandatory owing to complexity of the lesions.
Project description:ObjectiveVascular access induced digital ischaemia is an uncommon complication of haemodialysis access procedures and is difficult to manage. Several techniques have been described to treat this phenomenon, with variable long term success. Although all of these procedures have been shown to work, they have a significant failure rate, such as persistent high vascular access flow or loss of access. One of the major technical limitations of these techniques is the lack of quantitative data gathered during the procedure to ensure treatment success. In this study, the aim was to describe a novel technique that can improve the success of banding in preserving access and eliminating digital ischaemia.TechniqueA modified method for arteriovenous fistula banding that incorporates measurements of distal arterial pressure to improve the success of the procedure is described.ResultsSixteen patients with vascular access induced digital ischaemia and high-flow vascular access were treated using the technique. All procedures were technically successful. At 30 days, complete symptomatic relief (clinical success) was seen in 81% (n = 13) of patients. There was no access thrombosis or infection in any of the patients at the 30 day follow up. Six month follow up data were available in seven patients. There was no loss of access patency or recurrence of symptoms observed at six months.ConclusionThis novel technique is simple and effective and can be used safely as first line therapy for the management of vascular access induced digital ischaemia.
Project description:Coronary arteriovenous fistulas are congenital or acquired abnormalities characterized by abnormal communication between the coronary circulation and cardiac chambers or other vessels. Frequently, patients are asymptomatic and their diagnosis can be carried out incidentally by echocardiography. Knowing the echocardiographic findings characteristic of this malformation will prevent the diagnosis from going unnoticed.
Project description:IntroductionWe aimed to substantiate the benefit of postoperative handgrip exercises (HGEs) in enhancing the maturation of an arteriovenous wrist fistula.MethodsWe randomly assigned 119 patients aged 20 to 80 years who had wrist arteriovenous fistulas (AVFs) to undergo either a basic HGE program (group A), an advanced program (group B), or an advanced-plus upper arm banding program (group C). Outcomes were assessed by ultrasonographic evaluation of the diameter and flow at each follow-up. The attending nephrologist decided the clinical use of the fistula.ResultsWe identified no significant differences among the HGE groups in the mean diameter and blood flow 14, 30, 60, and 90 days after the creation of the wrist AVF (P = 0.55, 0.88, 0.21, and 0.19 for the diameter; 0.94, 0.81, 0.49, and 0.56 for the flow, respectively). The intent-to-treat analysis also found no difference in the clinical use of fistulas for hemodialysis (HD) (P = 0.997).ConclusionIn patients with a newly created wrist AVF, advancing frequency, with or without adding intensity using an upper arm tourniquet, of postoperative HGEs did not enhance the growth of the fistula or increase the rate of clinical use over 3 months. (ClinicalTrials.gov ID: NCT03077815).
Project description: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.