Arteriovenous Fistula Outcomes Research Articles

A decade of arteriovenous fistula creations in the ⩾75 years population: Equal opportunity or sub-optimal use of resources.

The optimal vascular access in the elderly remains contentious in the context of increasingly limited resources and anticipated survival on hemodialysis. Research focus has shifted to include the impact of vascular access on quality of life. This study explored clinical outcomes in individuals aged ⩾75 years who had an arteriovenous fistula (AVF) created in a single center over a 10-year period. Demographic and clinical data concerning AVFs created January 2009-December 2019 were identified from a prospective database for retrospective analysis. Outcome measures were AVF patency and failure to mature rates plus overall patient and vascular access survival. The Vascular Access Specific Quality of life measure (VASQoL) was completed in a contemporary cohort aged ⩾75 years established on HD in October 2021. AVF outcomes were available for 272 patients (93%). The failure to mature (FTM) rate was 36% with the significant predictors of AVF FTM being the creation of a radiocephalic AVF (OR 8.13, 95% CI 8.02-8.52, p < 0.01), female gender (OR 4.84, 95% CI 4.70-5.41, p < 0.01), and a history of peripheral vascular disease (OR 5.25, 95% CI 5.22-6.00, p value = 0.02). Functional patency was associated with a median 12-month survival benefit compared to those whose fistula FTM (p < 0.01). The median patency duration for a functionally patent AVF was 3 years. Elderly patients with a fistula reported a lower quality of life in VASQoL scoring than those with central venous catheters. In this cohort, AVF creation in individuals aged ⩾75 years AVFs was associated with comparable AVF patency rates to younger patients. AVF functional patency was associated with superior patient survival compared to those with AVF FTM. A multi-disciplinary surveillance program may help reduce AVF loss. Further work on how vascular access choice impacts quality of life in elderly patients is required.

Profile of Arteriovenous Fistula Surgery in Patients with Chronic Kidney Disease at a Tertiary Care Urology Hospital Karnataka, India: A Prospective Interventional Study

Introduction: Haemodialysis (HD) is the most important treatment approach in patients with Chronic Kidney Disease (CKD), awaiting kidney transplantation, demanding the longterm need for dialysis access. Aim: To study the profile of Arteriovenous Fistula (AVF) surgery in patients undergoing haemodialysis in the Karnataka region, India. Materials and Methods: This prospective, interventional singlecentre study was conducted at the Institute of Nephrology and Urology, KR Hospital Campus, Mysuru, India, from April 2018 to April 2021. All the patients undergoing haemodialysis with AVF aged between 11-90 years were included. Demographic details (age, sex, co-morbidities) and fistula-related complications associated with surgery were examined in the immediate, late, and delayed postoperative period. Categorical variables were presented as numbers and percentages whereas, continuous variables were expressed as mean {Standard Deviation (SD)}. The data was collected in Excel Sheet and the statistical analysis was performed using Statistical Package for Social Sciences (SPSS), version 20.0. Results: In total, 200 patients with a mean (SD) age of 48.8 (13.0) years underwent AVF formation and the majority were below &lt;60 years of age (n=154, 77.0%). The incidence of fistula surgery and patency rates was higher in men (n=140, 70.0%). Most patients had left non dominant arm (n=187, 93.5%) and remaining right non dominant arm (n=13, 6.5%). The most common site of AVF was left brachial cephalic (n=135, 67.5%). The most common cause of CKD was diabetes mellitus (n=90, 45.0%). The most common immediately observed complications were bleeding (n=13, 6.5%), pain (n=12, 6.0%) and oedematous limb (n=5, 5.0%). Stitch abscess was the most common late complication observed in 14 patients (7%). Rupture of the aneurysm and AVF failure were delayed complications observed in eight (1.5%) and 17 (8.5%) patients, respectively. Conclusion: In this study, bleeding, stitch abscess and AVF failure were found to be the most common immediate, late, and delayed postoperative complications, respectively. However, more studies are required to understand the outcome of AVF in Chronic Renal Failure (CRF) patients from India.

Doppler ultrasound assessment of calcified radial arteries prior to radio-cephalic arterio-venous fistula placement: an observational study.

In elderly and diabetic patients, arterial calcifications are prevalent and result in worse outcomes of arterio-venous fistulas (AVFs). Optimal ultrasound criteria for assessment of calcified arteries are unknown. We report our experience with ultrasound assessment of calcified arteries prior to placement of radio-cephalic (RC) AVFs. We included 85 patients in whom a RC-AVF placement was planned. Patients were divided according to the presence of radial artery calcifications into a calcified group (moderate/severe calcifications, N = 18) and control group (no changes/mild atherosclerosis, N = 67). Doppler ultrasound parameters were analyzed in the calcified group with focus on assessment of the artery, including grading of calcifications and Doppler measurements at rest and during reactive hyperemia (RH). In the calcified group mean patients' age was 72 ± 11 years, 72% were diabetics, mean resistance index (RI) during RH was 0.78 ± 0.09 (range 0.63-0.90). In 14 (78%) patients an AVF was successfully placed and in 12 it matured (67% maturation rate). A lower RI at rest was observed in the primary failure sub-group with high area under the ROC curve (0.89) and a cut-off value of 0.90 for RI. There was no difference in RI at RH between failed and matured AVFs. 1-year secondary patency was 66% and in eight patients with follow-up ultrasound available, blood flow was 350-1300 ml/min. For comparison, in the control group a radio-cephalic AVF was placed in all patients, primary failure rate was 6%, maturation rate 85% and 1-year secondary patency was 77%. Our very limited experience suggests that successful RC-AVF placement and maturation with good 1-year patency rates is possible in patients with moderately/severely calcified arteries and RI during RH of up to 0.90.

Clinical profile and outcome of arteriovenous fistulae in children onmaintenance hemodialysis from a low-resource setting.

Arteriovenous fistula (AVF) is the recommended access of choice in children on maintenance hemodialysis. The challenges of creating and maintaining a fistula in children are many. The objective of our study was to describe the clinical profile and outcomes of AVFs in children from a resource-limited setting. A retrospective analysis of children who have had an AVF for maintenance hemodialysis from 2010 to 2020 was performed. The center protocol for creation and management of complications was followed. Failure of fistula to mature was defined as primary failure. Primary patency was defined as the time from creation of access to the first complication requiring intervention. The primary failure rate, duration of primary patency and associated risk factors, and 1- and 3-year primary fistula patency rates were studied. Thirty-six children (38 AVFs) with the median (interquartile range) age of 11 (8, 13) years were included. Brachiocephalic anastomosis was the most common site (75%) of AVF. The primary failure rate was 5.5% (2 of 36). The mean (95% confidence interval) duration of primary patency was 42.3 (29.9, 54.7) months. There were no particular factors associated with the duration of primary patency. The 1- and 3-year primary patency rate was 91% and 73%, respectively. In resource-limited settings, AVF had good primary patency and is a feasible and durable access for maintenance hemodialysis in children.

Letter: Stereotactic Radiosurgery for Dural Arteriovenous Fistulas: A Systematic Review and Meta-Analysis and International Stereotactic Radiosurgery Society Practice Guidelines.

To the Editor: We read with interest the article by Singh et al1 synthesizing the modern literature around the use of stereotactic radiosurgery (SRS) in the treatment of cranial dural arteriovenous fistulas (DAVFs). Neurointervention has disrupted the established treatment paradigm for many neurosurgical conditions. From intracranial aneurysms and large vessel occlusions to hydrocephalus, neuroendovascular surgery favorably altered the natural history and reduced the treatment-related morbidity of these and other disease processes. This has changed the mindset of clinicians who treat patients with cerebrovascular disease. For instance, a patient with an unruptured wide-necked aneurysm may be better served with an endovascular treatment that leaves a small neck remnant than with clip reconstruction that affords complete occlusion but requires a considerably more invasive surgical approach. Endovascular therapy has, in a generally safe and minimally invasive fashion, lowered the clinical risk of many pathologies without affording complete cure. In light of the available literature, a similar shift in mindset may be warranted regarding SRS for the treatment of cranial DAVFs. Just as SRS met with initial skepticism regarding its efficacy for vestibular schwannomas,2 neurointerventionalists and cerebrovascular surgeons have been slow to embrace its utility for DAVFs.3 In recent years, mounting evidence has emerged to support the efficacy of SRS as more than just a salvage therapy after failed endovascular embolization of DAVFs.4,5 In light of this, a recent systematic review and meta-analysis by Singh et al1 on behalf of the International Stereotactic Radiosurgery Society has summarized the DAVF SRS outcomes and provided some practice guidelines. In their analysis of 705 SRS-treated patients with DAVF in 21 studies, the authors reported complete occlusion and symptomatic cure rates of nearly 70% and 80%, respectively.1 In comparison, a recent meta-analysis of transarterial DAVF embolization using ethylene vinyl alcohol copolymer (Onyx; Medtronic Neurovascular) reported a complete occlusion rate of 82%.6 A multicenter retrospective analysis of the Consortium for Dural Arteriovenous Fistula Outcomes Research (CONDOR) database reported a complete obliteration rate of 55% after initial Onyx embolization.7 In this CONDOR study, the final obliteration rate with Onyx was less than 70%, even after all treatments. Surgical DAVF series typically report a higher obliteration rates than endovascular series, but many of these surgical cases have failed endovascular therapy, and operative morbidity and mortality rates up to 17% have been reported.3,8,9 The rates of post-SRS hemorrhage and permanent neurological deficits reported by Singh et al1 in their meta-analysis were 1.1% and 1.3%, respectively. By comparison, the risk of permanent neurological deficit after DAVF embolization was 4% in the meta-analysis by Sadeh-Gonike et al6 and 16.1% in the CONDOR database.7 In a separate analysis of unruptured high-grade DAVFs from CONDOR, post-treatment hemorrhage rates in the observation, endovascular, surgical, and SRS groups were 6.9%. 1.6%, 2.3%, and 0%, respectively.4 Although there were relatively few patients in the SRS group (n = 19), the risk of post-treatment hemorrhage seems to be similar among the various therapeutic modalities for unruptured DAVFs. DAVFs can be rewarding lesions to address for neurointerventionalists, as they provide a satisfying combination of technical skill, anatomic knowledge, and innovative approaches (ie, transvenous, direct puncture, combined surgical and endovascular). However, these cases can require hours of radiation exposure for the patient over potentially multiple embolization sessions, and there is a modest risk of DAVF recurrence even after initial angiographic cure. Based on analyses of the CONDOR database, obliteration of a low-grade DAVF after a single embolization session was achieved in <40% of cases,10 and the rate of recurrent arteriovenous shunting after angiographic cure (which required a mean of >2 embolization sessions) was 7%.11 Based on these findings, SRS may warrant consideration as a first-line treatment for unruptured DAVFs.1 If patients understand the potential risks associated with the latency period between treatment and efficacy, SRS should be discussed with unruptured patients with DAVF as a viable and reasonable alternative to embolization and surgical ligation. Definitive evidence from randomized comparative trials among the various treatment strategies for DAVFs is unlikely to be forthcoming for such a rare condition. Therefore, we will continue to rely on large multicenter databases, such as CONDOR, for our best available evidence regarding management outcomes and complications in contemporary neurovascular practice. The practice guidelines put forth by the ISRS underscore the favorable risk to benefit profile of SRS for appropriately selected DAVFs.

In Reply: Stereotactic Radiosurgery for Dural Arteriovenous Fistulas: A Systematic Review and Meta-Analysis and International Stereotactic Radiosurgery Society Practice Guidelines.

To the Editor: We appreciate the insights regarding our systematic review and meta-analysis and practice guidelines from the International Stereotactic Radiosurgery Society (ISRS) on stereotactic radiosurgery (SRS) for dural arteriovenous fistulas (dAVFs) in a recent Letter to the Editor by Raper et al.1,2 As noted, our analysis found that SRS was estimated to result in complete obliteration (CO) rates of approximately 70% with very favorable symptom improvement and symptom cure rates of roughly 97% and 79%, respectively. CO rates after SRS compare quite favorably with those with Onyx embolization only per the Consortium for Dural Arteriovenous Fistula Outcomes Research (CONDOR) of approximately 55%.3 Of note, multimodality therapy with prior embolization was also noted to be associated with improved symptom cure rates in our analysis, suggesting a potential benefit in the therapeutic ratio for patients with poor prognostic factors for achievement of CO after either SRS or embolization alone. Treatment-related morbidity was also found to be quite limited with incidences of either permanent neurological deficits or hemorrhage after SRS both estimated to be roughly 1%. In our guidelines analysis, we were unable to report on favorable outcomes (as was performed in CONDOR and defined as achievement of CO without hemorrhage) because of lack of patient-level data. As noted, the risk of permanent neurological deficits after SRS compares favorably with embolization with estimates ranging from 4% to 16.1%.3,4 Previous analyses have noted similar rates of hemorrhage after embolization of 1.6%, quite similar to those observed in our analysis after SRS.3 We also noted in our analysis that previous hemorrhage was associated with a higher risk of hemorrhage after SRS similar to findings from CONDOR noting patients with prior hemorrhage had lower rates of favorable outcomes. The favorable risk profile and outcomes of SRS highlighted by our meta-analysis suggest it is an excellent therapeutic option for management of appropriately selected patients with dAVFs. Of note, limitations regarding both our analysis and CONDOR are inclusion of data from experienced and high volume sites that may not be reflective of sites with less experience in management of dAVFs. In the absence of prospective randomized data in part secondary to the rarity of dAVFs, prospective registries are key to further characterize both efficacy and toxicity of SRS for treatment of dAVFs. The prospectively maintained NeuroPoint Alliance SRS registry allows an avenue for analysis of patient-level data and further characterization of the impact of patient, lesion, and treatment characteristics on clinical outcomes after SRS for dAVFs.5 In addition, the International Radiosurgery Research Foundation (IRRF) has a long-standing history of conducting and publishing multi-institutional outcomes on SRS for a variety of indications. On the topic of SRS for dAVFs, the IRRF has published CO rates without hemorrhage ranging from 37% to 80% for 120 patients dependent on the presence of corticovenous reflux (CVR), prior hemorrhage, and noncavernous sinus (NCS) location.6 These findings are similar to our analysis where prior hemorrhage was associated with higher risk of hemorrhage after SRS and NCS dAVF associated with poorer CO and symptom control rates. Another analysis by the IRRF of 131 patients noted inferior CO rates in patients with NCS dAVFs as compared with cavernous sinus (CS) dAVFs with an association with CO and symptom improvement among NCS dAVFs but not among CS dAVFs.7 These findings in combination with those of our analysis suggest a need for improved CO rates, potentially through multimodality approaches for NCS dAVFs. The latency period for dAVFs, similar to arteriovenous malformations treated with SRS, has been characterized through work by the IRRF with similar rates of hemorrhage noted before and after SRS before CO being achieved.8 As noted by Raper et al, counseling on the risk of hemorrhage after SRS during the latency period is key as is patient selection given the association of prior hemorrhage and risk of hemorrhage during the latency period after SRS. Through these successful multi-institutional initiatives through the IRRF, robust clinical evidence has demonstrated the efficacy and safety of SRS for dAVFs. Further studies examining the potential role of multimodality approaches for patients at risk of unfavorable outcomes (particularly those with prior hemorrhages or NCS dAVFs) are warranted.

Characteristics and Outcomes of Arteriovenous Fistula in Hemodialysis Pediatric Patients: Impact of the Monocyte-to-Lymphocyte Ratio in Access Dysfunction

Characteristics and Outcomes of Arteriovenous Fistula in Hemodialysis Pediatric Patients: Impact of the Monocyte-to-Lymphocyte Ratio in Access Dysfunction

Outflow Patency Correlates with Radiosurgical Outcomes of Lateral Sinus Dural Arteriovenous Fistula.

To explore the impact of outflow patency on radiosurgical outcomes of lateral sinus dural arteriovenous fistulas (DAVFs). We retrospectively examined 83 lateral sinus DAVFs treated with Gamma Knife radiosurgery (GKRS) between 1995 and 2020. Two neuroradiologists blinded to the therapeutic outcomes served as imaging evaluators on pre-GKRS digital subtraction angiography and magnetic resonance images. The sinovenous outflow of lateral sinus DAVF was scored using combined conduit score (CCS), ranging from 0 (total occlusion) to 8 (full patency). The patients' follow-up magnetic resonance and digital subtraction angiography images were used to validate the radiosurgical outcomes (obliteration or non-obliteration) of lateral sinus DAVF. Cox regression and Kaplan-Meier analyses were performed to determine the correlations between the variables and outcomes. Among the 83 cases, 60 (72%) lateral sinus DAVFs achieved obliteration after a GKRS at a median latency period of 24.5months. After adjustment for aggressive presentation, cortical venous reflux, straight sinus reflux, and optic nerve sheath enlargement, a CCS of >6 was independently associated with lateral sinus DAVF obliteration (hazard ratio: 2.335, P=0.007). The estimated 36-month probabilities of obliteration were 80% versus 53.6% for lateral sinus DAVFs with a CCS of >6 versus ≤6. Lateral sinus DAVFs with a CCS of >6, indicating a nearly patent sinovenous outflow, were more likely to be obliterated after GKRS. Sinovenous outflow patency is a factor associated with therapeutic outcomes in radiosurgery for lateral sinus DAVFs.

Upper limb exercise for arteriovenous fistula maturation in people requiring permanent haemodialysis access.

The failure of arteriovenous fistulas (AVF) to mature is a major problem in patients with kidney failure who require haemodialysis (HD). Preoperative planning is an important factor in increasing functional AVF. Upper limb exercise has been recommended to gain AVF maturation. Studies of pre- and post-operative upper limb exercises in patients with kidney failure patients have been reported; however, the optimal program for this population is unknown due to inconsistent results among these programs. We aimed to determine if upper limb exercise would be beneficial for AVF maturation (prior to and post AVF creation) in patients with kidney failure and to improve AVF outcomes. This review also aimed to identify adverse events related to upper limb exercise. We searched the Cochrane Kidney and Transplant Register of Studies up to 15 March 2022 through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov, and other resources (e.g. reference list, contacting relevant individuals, and grey literature). We included randomised controlled trials (RCTs) and quasi-RCTs, comparing upper limb exercise training programs with no intervention or other control programs before or after AVF creation in patients with kidney failure. Outcome measures included time to mature, ultrasound and clinical maturation, venous diameter, blood flow in the inflow artery, dialysis efficacy indicator, vascular access function (functional AVF), vascular access complications, and adverse events. Study selection and data extraction were taken by four independent authors. Bias assessment and quality assessment were undertaken independently by two authors. The effect estimate was analysed using risk ratio (RR) with 95% confidence intervals (CI) for dichotomous data, or mean difference (MD) or standardised mean difference (SMD) for continuous data. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Nine studies (579 participants) were included, and seven studies (519 participants) conducting post-operative exercise training could be meta-analysed. Three comparisons were undertaken: (i) isotonic exercise training versus no intervention; (ii) isometric versus isotonic exercise training; and (iii) isotonic (high volume) versus isotonic exercise training (low volume). Due to insufficient data, we could not analyse pre-operative exercise training. Overall, the risk of bias was low for selection and reporting bias, high for performance and attrition bias, and unclear for detection bias. Compared to no intervention, isotonic exercise training may make little or no difference to ultrasound maturation (2 studies, 263 participants: RR 1.09, 95% CI 0.94 to 1.25; I² = 0%; low certainty evidence), but may improve clinical maturation (2 studies, 263 participants: RR 1.14, 95% CI 1.02 to 1.27; I² = 0%; low certainty evidence). Compared to isotonic exercise training, isometric exercise training may improve both ultrasound maturation (3 studies, 160 participants: RR 1.56, 95% CI 1.21 to 2.00; I² = 22%; low certainty evidence) and clinical maturation (3 studies, 160 participants: RR 1.80, 95% CI 1.18 to 2.76; I² = 53%; low certainty evidence). Venous diameter (3 studies, 160 participants: MD 0.84 mm, 95% CI 0.45 to 1.23; I² = 0%; low certainty evidence) and blood flow in the inflow artery (3 studies, 160 participants: MD 140.62 mL/min, 95% CI 38.72 to 242.52; I² = 0%; low certainty evidence) may be greater with isometric exercise training. It is uncertain whether isometric exercise training reduces vascular access complications (2 studies, 110 participants: RR 2.54, 95% CI 0.38 to 17.08; I² = 47%; very low certainty evidence). It is uncertain whether high volume isotonic exercise training improves venous diameter (2 studies, 93 participants: MD 0.19 mm, 95% CI -0.75 to 1.13; I² = 34%; very low certainty evidence) or blood flow in the inflow artery (1 study, 15 participants: MD -287.70 mL/min, 95% CI -625.99 to 60.59; very low certainty evidence) compared to low volume isotonic exercise training. None of the included studies reported time to mature, dialysis efficacy indicator, vascular access function, or adverse events. Our findings suggest that the current research evidence examining upper limb exercise programs is of low quality, attributable to variability in the type of interventions used and the overall low number of studies and participants.

Hemodialysis Access Outcome in Elderly Population and its Association with Mortality

Objective: to determine the outcome of arteriovenous fistula in the elderly compared to the younger age group and its association with mortality so that the best approach to hemodialysis access can be defined.&#x0D; Study Design: Prospective longitudinal study&#x0D; Place and Duration of Study: Department of Vascular Surgery, CMH, Lahore Pakistan, from Jan 2020 to Aug 2021.&#x0D; Methodology: All the Patients who presented to access the Surgical Clinic were categorized into three groups according to their age. Outcome variables like fistula maturation, complications and mortality were compared according to age groups.&#x0D; Result: A total of 184 patients were recruited. We found that in the age group &gt;70 years, there was male predominance (12, 54.5%), three-quarters of them were on hemodialysis at the time of access surgery, only half of them were functional at one year of follow-up, and 6 (27.3%) were not alive at the time of contact. In addition, the pseudo aneurysm was the most common complication in this group, which was the most dreadful of all access-related complications and further put the already frail at risk.&#x0D; Conclusion: No single optimal approach can be expected to meet the needs of all, and an extensive patient-centred case-based discussion is required for each patient in the hope that optimal dialysis access can be created. Age cannot be defined as an independent risk factor for access creation.

Early Failure of Arteriovenous Fistula (AVF): The Effect of Diabetes and Hypertension in a Cross-Sectional Study.

Background: Identification and control of clinical predictors of arteriovenous (AVF) failure can improve the long-term outcome of hemodialysis patients. The effects of these factors on the outcome of AVF are not still clear. So, we aimed this study to compare the effect of hypertension and diabetes on early failure of AVF. Methods: In this retrospective study, we evaluated 400 patients with ESRD referred to our clinic for the creation of the first AVF from July 14, 2001, through August 7, 2018. One month after AVF creation, the patients were referred to the clinic for patency control. Demographic characteristics, previous history of diabetes and hypertension, and laboratory data of all patients were recorded preoperatively. Data were entered to SPSS v.24 and Study data were analyzed with chi-square and independent student t-test. Then, early failure of AVF and its relationship with a history of diabetes and hypertension were assessed. Results: There was no statistically significant relationship between the history of diabetes and early AVF failure risk in ESRD patients (OR, 0.78; 95% CI, 0.25 to 2.43). Furthermore, the history of hypertension was significantly lower in the early failure of AVF group (OR, -2.82; 95% CI, -1.42 to -5.59). Although, this effect faded when using regression analysis (OR, -2.67; 95% CI, -0.97 to -7.36). There was a higher Body mass index in the non-early failure group (p = 0.041). There was no significant difference in age (p = 0.512), gender (p = 0.091), history of smoking (p = 0.605), treatment with insulin (p = 0.683), oral antidiabetic agents (p = 0.734), duration of diabetes (p = 0.384), and duration of hypertension (p = 0.093). Conclusion: We reported that the history of diabetes was not higher in the early failure group, while there was a lower risk of AVF failure in patients with a previous history of hypertension.

Effect of Anticoagulant and Antiplatelet Drugs on Outcome of Arterio-Venous Fistula Created for Hemodialysis Access

Background: Arteriovenous fistula (AVF) creation is the primary mode of achieving vascular access for hemodialysis in chronic renal failure (CRF). Because of high complication rates like thrombosis, maintenance of the fistula is a major challenge. Although antiplatelet and anticoagulant drugs are emerging rapidly for improving the outcome of AVF but fear of bleeding, hematoma, subsequent compression of AV fistula and blockade restrict their use in many dialysis centers. Objective: To see the effect of anticoagulant &amp; antiplatelet drugs in improving primary patency rate and reducing early thrombus formation of AVF. Methods: This clinical trial was conducted in the Department of Urology Bangabandhu Sheikh Mujib Medical University, Dhaka from November, 2018 to October, 2019. Ninety six ESRD patients who underwent AV fistula with immediate postoperative had thrill and murmur were included as study population as per selection criteria. Informed written consent was taken from all the patients. Patients were divided into two groups using computer generated random number (group I and group II). In group I, patients anticoagulation and antiplatelet drugs were used and in group II, patients anticoagulation and antiplatelet drugs were not used after creation of AVF. Patients were followed up on 3rd POD, at 2 weeks and at 4 weeks after the operation and re-evaluated with clinical examinations and investigations. The outcome were evaluated and compared between two groups. Results: In this study maximum patients were more than 40 years old in both groups. Mean age was 47.89 ± 12.54 years in group I and 46.29 ± 14.78 in group II. Males were predominant in both groups. Male to female ratio was 3.36:1 and 5.8:1 in group I and group II respectively in this study. In this study 35.4% in Group I and 45.8% in Group II patients had hypertension. 47.9% in Group I and 60.4% in Group II patients had DM. Thrombosis was significantly lower in study group (group I) than control group (group II). Primary patency was significantly higher at 4th week after treatment in group I than group II. Bleeding was observed in one (2.1%) patients at 1rd POD in group I who came with emergency &amp; managed conservatively. Haematoma was observed in 1 (2.1%) patients at 3rd POD in group I. Conclusion: Use of antiplatelet and anticoagulant agents prevented the loss of AV patency. But it still needs to be determined whether the potential benefits of anticoagulant &amp; antiplatelet therapy outweights the risk of adverse events. Bangladesh J. Urol. 2021; 24(1): 90-98

Revisiting the Role of Ultrasound Mapping in Arteriovenous Fistula Formation: A Single-Center Experience

Background: The global prevalence of chronic kidney disease (CKD) continues to increase, with the arteriovenous fistula (AVF) as the most preferred vascular access for hemodialysis. Whether routine preoperative ultrasound mapping improves the outcome of AVF formation compared with clinical examination alone remains controversial. Methods: This retrospective study included patients undergoing AVF surgery with and without preoperative ultrasound at our center between September 2017 and August 2020. Outcome measures included AVF early and mid-term outcome. Cox regression analysis was performed to identify independent predictors of favorable AVF outcome. Results: A total of 158 patients received an AVF during the study period. Both groups with (n = 79) and without (n = 79) ultrasound mapping were similar regarding baseline characteristics (age, sex, comorbidities). Patency rates were comparable between the 2 groups at 30 days, 3 months, and 6 months after AVF surgery, although there was a trend toward more favorable outcome for the mapping group ( P = .07). Kaplan-Meier analysis showed that at the end of study, the ultrasound mapping group had a higher mid-term patency rate; however, the improvement was not significant ( P = .07). Cox regression analysis did not reveal age, gender, comorbidities, and ultrasound as predictors of AVF survival. Conclusion: Our study did not find a significant benefit from routine preoperative ultrasound mapping in creating AVFs for hemodialysis. Further well-designed and adequately powered trials are needed to demonstrate the beneficial role of routine preoperative ultrasound mapping for vascular access in CKD coupled with clinical evaluation in short- and long-term AVF outcome.

Vascular Factors Affecting Outcomes of Snuffbox AV Fistula with Side-to-Side Anastomosis: A Single Institutional Observational Study

Background: Angioaccess is considered the "Tendon of Achilles" for hemodialysis. Arteriovenous fistula (AVF) is the commonly entailed vascular access for hemodialysis. Objectives: The present study evaluates the outcomes of anatomical snuffbox AVF by preoperative and postoperative color Doppler scans. It also determines the anatomical snuffbox AVF maturation rate concerning preoperative radial artery diameter (RAD), cephalic vein diameter (CVD), cephalic vein distensibility, and peak systolic velocity (PSV). Methods: This study was conducted from April 2020 to January 2021 on end-stage renal diseases (ESRD) patients undergoing an operation for anatomical snuffbox AVF creation at our center after taking permission from the institutional ethics committee and written informed consent from patients. Results: Thirty-five ESRD patients underwent snuffbox arteriovenous fistula (SBAVF) creation, including 68% males and 32% females. Diabetes mellitus was noted in 40% and hypertension in 80%. Successful AVF maturation was noted in 92% (69.57% of males and 30.43% of females). The mean RAD assessed on color Doppler ultrasonography (CDUS) preoperatively was 1.79 mm, while the peak velocity of the radial artery at the snuffbox was 23.80 cm/s. Conclusions: We recommend applying the side-to-side configuration as its anastomosis angle is less owing to the lesser kink on the anastomotic site. A longer segment of anastomosis is achieved, and better fluid dynamics and WSS profiles are seen in this configuration with good outcomes.

A Practical Grading Scale for Predicting Outcomes of Radiosurgery for Dural Arteriovenous Fistulas: JLGK 1802 Study

Background and Purpose To assess the long-term outcomes of intracranial dural arteriovenous fistula (DAVF) treated with stereotactic radiosurgery (SRS) alone or embolization and SRS (Emb-SRS) and to develop a grading system for predicting DAVF obliteration. Methods This multi-institutional retrospective study included 200 patients with DAVF treated with SRS or Emb-SRS. We investigated the long-term obliteration rate and obliteration-associated factors. We developed a new grading system to estimate the obliteration rate. Additionally, we compared the outcomes of SRS and Emb-SRS by using propensity score matching. Results The 3- and 4-year obliteration rates were 66.3% and 78.8%, respectively. The post-SRS hemorrhage rate was 2%. In the matched cohort, the SRS and Emb-SRS groups did not differ in the rates of obliteration (P=0.54) or post-SRS hemorrhage (P=0.50). In multivariable analysis, DAVF location and cortical venous reflux (CVR) were independently associated with obliteration. The new grading system assigned 2, 1, and 0 points to DAVFs in the anterior skull base or middle fossa, DAVFs with CVR or DAVFs in the superior sagittal sinus or tentorium, and DAVFs without these factors, respectively. Using the total points, patients were stratified into the highest (0 points), intermediate (1 point), or lowest (≥2 points) obliteration rate groups that exhibited 4-year obliteration rates of 94.4%, 71.3%, and 60.4%, respectively (P<0.01). Conclusions SRS-based therapy achieved DAVF obliteration in more than three-quarters of the patients at 4 years of age. Our grading system can stratify the obliteration rate and may guide physicians in treatment selection.

Gender Disparities in Arteriovenous Fistula Maturation Outcomes

The end-stage kidney disease life plan aims to individualize hemodialysis (HD) access selection in patients requiring renal replacement therapy. Paucity of data on risk factors for poor arteriovenous fistula (AVF) outcomes limits the ability of physicians to guide their patients on this decision. This is especially true for women, who are known to have worse AVF outcomes when compared with men. The goal of this study was to identify risk factors associated with poor AVF maturation outcomes in women that will help guide individualized access selection.

Intraoperative Vascular Mapping During Hemodialysis Access Surgery Improves Patient Eligibility for Arteriovenous Fistula Creation

Currently, there is no consensus on how best to evaluate the suitability of vessels for arteriovenous fistula (AVF) creation. Preoperative sonographic vascular mapping performed by a vascular imaging facility is commonly used despite the lack of evidence on AVF outcomes. The goal of this study was to evaluate the utility of intraoperative vascular mapping performed by the operating surgeon during access creation.

Clinical Characteristics and Outcome of Arteriovenous Fistula among Patients Undergoing Haemodialysis with end Stage Renal Disease

Objective: To determine the clinical characteristics and failure rate of arteriovenous fistula (AVF) among patients undergoing haemodialysis with end stage renal disease. Methodology: This was a cross-sectional study, done at department of urology at Bilawal Medical College for Boys, Liaquat University of Medial and Health Sciences Jamshoro Pakistan, with time duration of eleven months from April 2021 to February 2022. All the patients with age of more than 20 years, both genders, end stage renal disease and undergoing haemodialysis were included. The optimal site for fistula development was determined after taking blood pressure and completing the Allen test. Vascular diameter, intravascular thrombosis, arterial wall atherosclerosis, and the opening of arterial inflow and venous outflow access were all assessed during the procedure. End- to- side and side-to-side arteriovenous fistula were established if there were no contraindication. The patients were discharged after establishing the fistula's patency and experiencing the thrill. The patient's fistula patency and hemodialysis performance were assessed till six weeks. All the information was documented in the self-made proforma. SPSS version 26 was used for the data analysis. Results: A total of 100 cases were studied, most of the cases (49.0%) were more than 50 years old and males were most common 71.0%. Out of all, 59(59.0%) cases were diabetics and hypertensive. According to the site of arteriovenous fistulae (AVF), Left radio cephalic AVF was31.0%, left brachio cephalic AVF was 40.0%, left brachio basilic AVF 24.0%, right radio cephalic AVF 03.0%, right Brachio cephalic AVF 1.0% and right brachio basilic AVF 1.0%. At 6th week follow-up arteriovenous fistula was observed successfully functional in 91.0% cases, while 5.0% arteriovenous fistula were burst and in 3.0% it was failed, while one patient was died during this six-weeks follow-up. Conclusion: For haemodialysis, the arteriovenous fistula was observed to be the best and preferable option with higher functioning rate, noninvasive and lower complicated. Keywords: Renal failure, AVF, function, failure

Dural arteriovenous fistulas without cortical venous drainage: presentation, treatment, and outcomes.

Current evidence suggests that intracranial dural arteriovenous fistulas (dAVFs) without cortical venous drainage (CVD) have a benign clinical course. However, no large study has evaluated the safety and efficacy of current treatments and their impact over the natural history of dAVFs without CVD. The authors conducted an analysis of the retrospectively collected multicenter Consortium for Dural Arteriovenous Fistula Outcomes Research (CONDOR) database. Patient demographics and presenting symptoms, angiographic features of the dAVFs, and treatment outcomes of patients with Borden type I dAVFs were reviewed. Clinical and radiological follow-up information was assessed to determine rates of new intracranial hemorrhage (ICH) or nonhemorrhagic neurological deficit (NHND), worsening of venous hyperdynamic symptoms (VHSs), angiographic recurrence, and progression or spontaneous regression of dAVFs over time. A total of 342 patients/Borden type I dAVFs were identified. The mean patient age was 58.1 ± 15.6 years, and 62% were women. The mean follow-up time was 37.7 ± 54.3 months. Of 230 (67.3%) treated dAVFs, 178 (77%) underwent mainly endovascular embolization, 11 (4.7%) radiosurgery alone, and 4 (1.7%) open surgery as the primary modality. After the first embolization, most dAVFs (47.2%) achieved only partial reduction in early venous filling. Multiple complementary interventions increased complete obliteration rates from 37.9% after first embolization to 46.7% after two or more embolizations, and 55.2% after combined radiosurgery and open surgery. Immediate postprocedural complications occurred in 35 dAVFs (15.2%) and 6 (2.6%) with permanent sequelae. Of 127 completely obliterated dAVFs by any therapeutic modality, 2 (1.6%) showed angiographic recurrence/recanalization at a mean of 34.2 months after treatment. Progression to Borden-Shucart type II or III was documented in 2.2% of patients and subsequent development of a new dAVF in 1.6%. Partial spontaneous regression was found in 22 (21.4%) of 103 nontreated dAVFs. Multivariate Cox regression analysis demonstrated that older age, NHND, or severe venous-hyperdynamic symptoms at presentation and infratentorial location were associated with worse prognosis. Kaplan-Meier curves showed no significant difference for stable/improved symptoms survival probability in treated versus nontreated dAVFs. However, estimated survival times showed better trends for treated dAVFs compared with nontreated dAVFs (288.1 months vs 151.1 months, log-rank p = 0.28). This difference was statistically significant for treated dAVFs with 100% occlusion (394 months, log-rank p < 0.001). Current therapeutic modalities for management of dAVFs without CVD may provide better symptom control when complete angiographic occlusion is achieved.

Consortium for Dural Arteriovenous Fistula Outcomes Research (CONDOR): rationale, design, and initial characterization of patient cohort.

Cranial dural arteriovenous fistulas (dAVFs) are rare lesions, hampering efforts to understand them and improve their care. To address this challenge, investigators with an established record of dAVF investigation formed an international, multicenter consortium aimed at better elucidating dAVF pathophysiology, imaging characteristics, natural history, and patient outcomes. This report describes the design of the Consortium for Dural Arteriovenous Fistula Outcomes Research (CONDOR) and includes characterization of the 1077-patient cohort. Potential collaborators with established interest in the field were identified via systematic review of the literature. To ensure uniformity of data collection, a quality control process was instituted. Data were retrospectively obtained. CONDOR comprises 14 centers in the United States, the United Kingdom, the Netherlands, and Japan that have pooled their data from 1077 dAVF patients seen between 1990 and 2017. The cohort includes 359 patients (33%) with Borden type I dAVFs, 175 (16%) with Borden type II fistulas, and 529 (49%) with Borden type III fistulas. Overall, 852 patients (79%) presented with fistula-related symptoms: 427 (40%) presented with nonaggressive symptoms such as tinnitus or orbital phenomena, 258 (24%) presented with intracranial hemorrhage, and 167 (16%) presented with nonhemorrhagic neurological deficits. A smaller proportion (224 patients, 21%), whose dAVFs were discovered incidentally, were asymptomatic. Many patients (85%, 911/1077) underwent treatment via endovascular embolization (55%, 587/1077), surgery (10%, 103/1077), radiosurgery (3%, 36/1077), or multimodal therapy (17%, 184/1077). The overall angiographic cure rate was 83% (758/911 treated), and treatment-related permanent neurological morbidity was 2% (27/1467 total procedures). The median time from diagnosis to follow-up was 380 days (IQR 120-1038.5 days). With more than 1000 patients, the CONDOR registry represents the largest registry of cranial dAVF patient data in the world. These unique, well-annotated data will enable multiple future analyses to be performed to better understand dAVFs and their management.