Arteriovenous Fistula Survival Research Articles

Incremental hemodialysis and vascular access complications: a 12-year experience in a hospital hemodialysis unit.

Incremental hemodialysis (HD) is considered a valid alternative for patients with residual kidney function. Evidence concerning its effect on vascular access is scarce. We present our 12-year experience of an incremental hemodialysis program with the aim of evaluating survival and complications of arteriovenous fistula in these patients compared to the thrice-weekly scheme. From January 1st, 2006 to December 31st, 2017, 220 incident patients startedhemodialysis, 132 (60%) of whom began hemodialysis with two sessions per week and 88 (40%) with three sessions per week. Demographic and clinical variables were assessed at the start of treatment. Data regarding arteriovenous fistula survival and complications were collected. Both groups had similar baseline sociodemographic and clinical characteristics. A total of 188 (85%) patients were dialyzed with an arteriovenous fistula during follow-up. Eighty-three patients had one or more fistula complications, with no differences between incremental and conventional groups (p = 0.55). Fistula survival rates showed no significant difference between the two groups, whether analyzed from the date of fistula creation (Log Rank p = 0.810) or from the date of initial fistula cannulation (Log Rank p = 0.695). We found no differences in arteriovenous fistula survival or complication rate between patients who started HD with an incremental versus a conventional treatment scheme. Randomized controlled clinical trials may be warranted to achieve a higher degree of evidence.

#1487 Preoperative ultrasound vascular mapping as a predictor of arteriovenous fistula survival: a prospective cohort study

Abstract Background and Aims The morbidity and mortality of hemodialysis (HD) patients is directly related to the vascular access (VA) type. The arteriovenous fistula (AVF) is considered the VA of choice. When compared to the use of catheter, the use of AVF encompasses a lower infectious complications rate and a higher survival rate. The use of catheter has been independently associated with an increased risk of morbidity and mortality, especially during the first year of treatment. It is essential that HD programs maintain a high incidence and prevalence of AVF as a VA. For that reason, a multidisciplinary management is mandatory, with the collaboration of nephrologists, vascular surgeons, radiologists, and nurses. All patients who have an indication of AVF should have a prior ultrasound vascular mapping performed by the nephrologist to determine the most appropriate type of AVF. According to guidelines, there are several factors that increase the risk of AVF failure including advanced age, history of smoking, diabetes mellitus and peripheral vascular disease, among others. Therefore, the aim of this study is to determine the benefits of performing a preoperative ultrasound vascular mapping in terms of AVF survival. The secondary objective is to associate some risk factors to a higher rate of AVF failure. Method We conducted a prospective cohort study between January 2020 and December 2023. The viability of AVF was compared between AVF resulting from a preoperative ultrasound vascular mapping and those AVF without previous mapping. A multivariate analysis was performed with the entire population to determine the factors related to AVF survival. Results This study analyzed a total of 136 AVF, both native and prosthetic. Our population included 106 patients, mostly men (69.79%), with a median age of 68 years old (IR: 56-76), and history of smoking in a 39.10%, of diabetes in a 42.43%, and of peripheral vascular disease in a 17.54%. A preoperative ultrasound vascular mapping was previously performed in 107 AVF (78.7%). A total of 93 AVF were functional (68.4%). Regarding the analyzed risk factors of AVF failure (including advanced age and history of smoking, diabetes mellitus and peripheral vascular disease, and elbow/wrist AVF), we observed that advanced age and elbow AVF were related to higher survival of the AVF (p = 0.048 and p = 0.01 respectively). In the multivariate analysis we observed that advanced age and elbow AVF were independent predictors of AVF survival (p = 0.038 and p = 0.001, respectively). When comparing the cohorts, in the AVFs were the preoperative vascular ultrasound was performed, 78 AVF were functional (72.9%). In the AVFs were no mapping was performed, 15 AVF were functional (51.7%). This difference was statistically significant (p = 0.03). This implies a 21.2% increase in the probability of AVF survival when performing our AVF mapping. Conclusions The performance of a preoperative ultrasound vascular mapping by the nephrologist in our population has been associated to a significant increase in AVF survival. For that reason, we consider that it is an indispensable tool for the creation and monitoring of VA. When analyzing risk factors classically associated to AVF failure, we found that advanced age and elbow AVF were independent predictors of higher AVF survival. Other risk factors, such as history of diabetes mellitus, smoking, and peripheral arterial disease, were not significantly related to AVF failure in our population.

#2826 The Charlson Comorbidity Index in Registry-Based Research for Survival of Vascular Access

Abstract Background and Aims Several studies have reported higher haemodialysis survival in women; however, the influence of gender on arteriovenous fistula survival has not been extensively studied. For this reason, our aim is to estimate the prevalence of arteriovenous fistulae according to gender, adjusted by the Charlson comorbidity index. Method Retrospective study in patients on haemodialysis programme, by consulting electronic records over a period of 35 months. Demographic variables, primary and secondary patency events were included. The population was categorised on the basis of the Charlson Index and gender. Statistical analysis was performed using Kaplan Meyer survival curves to contrast the impact of comorbidities on the different patency events. Results 52 patients were evaluated, with a mean age of 70.7 ± 1.57 years, 69.2% men, 30.8% women, 42.3% diabetic, Charlson with a median of 7 (6.5 - 7.73), 98.1% had a native fistula, being more frequent the location in the humeral head (63.5%) and predominantly in the left upper limb (65.4% ). 21.2% of patients required some intervention on their AVF. The time required to achieve an event in both primary patency and secondary patency was longer in patients with a Charlson Index less than or equal to 7, and this was statistically significant (Log Rank Test (Mantel-Cox): primary patency p=0.003 and secondary patency p=0.002). In the group of women with a Charlson comorbidity index less than or equal to 7, mean survival for primary and secondary patency was even higher than in all patients, with statistical significance (Log Rank Test (Mantel-Cox ): primary patency p=0.005 and secondary patency p=0.008), a situation not repeated in men where no significant differences in survival were found when analysed according to the Charlson index. Conclusion The Charlson index in our population is a significant factor in the survival of AVFs in women.

#2833 Charlson comorbidity index predicts early failure and overall survival of vascular access among diabetic dialysis patients.

Abstract Background and Aims Vascular access (VA) survival is a determinant factor in the morbidity and mortality of haemodialysis patients, directly influencing their quality of life. Some studies have described the influence of diabetes on the reduced survival of arteriovenous fistulas as an independent factor; however, the correlation between other comorbidities in diabetic patients with vascular access survival has been less well documented. Therefore, our aim is to describe the relationship between comorbidities in diabetic haemodialysis patients and arteriovenous fistula (AVF) patency. Method Descriptive, observational and retrospective study in prevalent patients included in a haemodialysis programme by consulting electronic records over a period of 35 months. Demographic variables; related to vascular access and primary and secondary patency of all accesses were included. The Charlson Comorbidity Index was used to categorise diabetic patients according to comorbidities. Kaplan Meyer survival curves were used to contrast the impact of comorbidities on the different patency. Results 22 patients, mean age 68.36 ± 10.9 years, 68.18% male, 31.82% female, Charlson index with a median of 6.5 (5 - 8), 95.45% had a native fistula, with humero-cephalic location being more frequent (72.72%) and predominance of the left upper arm (68.18%). The time required to reach an event in both primary patency and secondary patency in diabetic patients was longer in patients with a Charlson index less than or equal to 7, this being statistically significant (Log Rank Test (Mantel-Cox): primary patency p=0.022 and secondary patency p=0.032). Conclusion The Charlson Comorbidity Index in our population is a significant factor in arteriovenous fistula survival.

#1335 Distal radio-cephalic arteriovenous fistula survival: comorbid conditions and long-term surveillance in hemodialysis

Abstract Background and Aims With a low incidence of infection and distal ischemia, the distal radio-cephalic arteriovenous fistula (dRCF) is the reference access for hemodialysis (HD). Smaller venous diameter and obesity have been associated with poor distal arteriovenous fistula (AVF) outcomes in some studies. On the other hand, HD patients often suffer from multiple co-morbidities, resulting in an increased number of complications. The impact of all these factors on vascular access survival has not been entirely characterized. We evaluated long-term follow-up demographic and clinical data from a cohort of patients in relation to primary and secondary dRCF survival. Method The study included prevalent patients who had been receiving hemodialysis for at least 6 months at the same reference hospital. From 2008 to 2023, we retrospectively collected dRCF for HD performed by a single reference surgical team. All dRCF could be confirmed to be clinically useful for dialysis (i.e., functional patency). Socio-demographic data were collected. Our medical team (nephrologist and radiologist) periodically performs a physical examination and duplex ultrasound to identify physical signs of possible complications, understand the underlying cause and plan treatment in advance. The time to first repair is termed primary AVF survival, while secondary survival is the time after first repair. Primary and secondary survival analysis was performed using the Kaplan-Meier method. Results Of 253 prevalent patients receiving HD, 82.2% had an AVF. The mean HD vintage was 61 ± 50 months. HD was started on a planned basis in 61.4% of cases, with AVF being the initial access in 71.7% of cases. We included 145 dRCFs for HD. dRCF was the unique AVF that was placed in 74.5% of the patients. Mean age 69.5 ± 14.5 (years), women 31%, mean BMI 27.3 ± 6.08 kg/m2, non-smokers 46.9%, obesity 37.9%, diabetes mellitus 44.8%, ischemic cardiopathy 20%, peripheric vasculopathy 15.9%. Diabetic nephropathy was the most common cause of chronic kidney disease in our population, accounting for 44.8% of cases. dRCF primary failure was 11.11%, 40% of these patients were over 80 years of age. The dRCF was left-sided in 82.2%. dRCF median survival was 64.5 ± 50.4 months; survival rates at 12, 36 and 60 months were 92%, 67% and 41%, respectively. Primary and secondary dRCF median survival was 33 ± 39 months and 50 ± 45 months, respectively. Primary and secondary survival rates at 12, 36 and 60 months were 60%, 32% and 17% and 84%, 53% and 33%, respectively. With a median survival of 62 ± 44 months, 29.7% of the dRCF did not undergo repair either before or during dialysis. The dRCF requiring percutaneous intervention and/or surgical reanastomosis before dialysis was 16.7%. Factors identified as being associated with lower primary survival were obesity and peripheral vasculopathy (p=0.01 and p=0.001, respectively), as shown in Figs. 1 and 2. The percentage of salvage procedures (percutaneous, surgical or both) in obese was 78,2%; 76,7% involved surgical repair, most of which were lipectomies, superficializations with or without transposition. Although not statistically significant (p=0.056), dRCF secondary survival is decreased in diabetic patients (Fig. 3). No statistical impact was found between age, sex, smoking, or ischemic cardiopathy and either primary or secondary survival. Conclusion Our obese patients on HD are a special population with an increased need for surgical reintervention of dRCF, which impacts primary but not secondary survival. Primary dRCF survival is lower in patients with peripheral vascular disease compared to other comorbidities; however, this vasculopathy is not associated with worse secondary dRCF survival with active follow-up. It is likely that individualized and careful long-term active surveillance was a key aspect in improving the functional patency of dRCF in our patients with multiple comorbidities. Undoubtedly, these issues deserve further prospective investigation.

Analysis of patency rates and factors associated with arteriovenous fistula in maintenance hemodialysis patients followed for 10 years

Objective This study analyzed the long-term arteriovenous fistula (AVF) patency rate and its determinants in patients undergoing maintenance hemodialysis. Methods General data and laboratory examinations of hemodialysis patients were collected retrospectively. The primary patency time, primary functional patency time, cumulative patency time, cumulative functional patency time, and temporary central venous catheterization (CVC) time were counted. Cox regression was used to analyze the relationships between different factors and AVF survival time. Kaplan-Meier survival analysis was used to analyze the primary patency, primary functional patency, cumulative patency, and cumulative functional patency rates between different groups. Results A total of 174 patients were included (mean age 58.38 ± 15.35 years), 57 women (32.76%) and 68 diabetics (39.08%). Univariate and multivariate Cox regression showed a correlation between UCR and AVF primary patency time, primary functional patency time, cumulative patency time, and cumulative functional patency time (HR 1.127, 1.116, 1.127, 1.115, 1.088, 1.075, 1.087, 1.013; 95%CI 1.055–1.204, 1.043–1.194, 1.055–1.204, 1.042–1.194, 1.022–1.158, 1.006–1.149, 1.021–1.157, 1.004–1.147; p < 0.001, 0.001, <0.001, 0.002, 0.008, 0.033, 0.009, 0.039, respectively). Duration of temporary CVC was also correlated (HR 1.013, 1.013, 1.013, 1.014, 1.008, 1.008, 1.008, 1.008; 95%CI 1.007–1.018, 1.008–1.019, 1.008–1.019, 1.009–1.020, 1.004–1.012, 1.004–1.012, 1.004–1.012, 1.004–1.012; p < 0.001, <0.001, <0.001, <0.001, <0.001, <0.001, <0.001, <0.001, respectively). Female sex was correlated with the primary patency time and the primary functional patency time (HR 1.755, 1.765, 1.767; 95%CI 1.028–2.997, 1.034–3.014, 1.021–3.057; p = 0.039, 0.037, 0.042, respectively), but not with the cumulative patency time and the cumulative functional patency time, the primary patency rate and primary functional patency rate of AVF were higher in male than in female patients (χ2 = 4.439, 4.531; p = 0.035, 0.033, respectively). The primary patency rate, primary functional patency rate, cumulative patency rate, and cumulative functional patency rate of AVF with UCR > 10.11 group are lower than those with UCR ≤ 10.11 (χ2 = 10.745, 10.712, 4.605, 4.472; p = 0.001, 0.001, 0.032, 0.034, respectively). The group of DTCP ≤ 42 days is better than DTCP > 42 days (χ2 = 6.014, 6.055, 8.572, 8.461; p = 0.014, 0.014, 0.003, 0.004, respectively). Conclusion Women with high UCR values at the beginning of dialysis and a long duration of temporary CVC have a poor long-term survival rate of AVF. Therefore, UCR can be used as an indicator to predict the long-term survival rate of AVF. Simultaneously, clinicians should remove the temporary catheter as early as possible if conditions permit it.

Cannulation Technique of Vascular Access in Hemodialysis and the Impact on the Arteriovenous Fistula Survival: Systematic Review and Meta-Analysis.

Adequate cannulation technique (CT) methods and successful puncture are essential for hemodialysis (HD) and arteriovenous fistula (AVF) maintenance. This systematic review and meta-analysis was designed to identify which CT allows better AVF primary patency and lower rates of complications in HD patients. The search was carried out on the CINAHL, MEDLINE, Cochrane Library, and Joanna Briggs Institute Library databases to identify all randomized controlled trials (RCTs) and observational studies comparing clinical outcomes of buttonhole (BH) versus rope ladder cannulation (RL) from 2010 to 2022. The Risk-of-Bias (Rob 2) tool was used for RCTs and the ROBINS-I was used for non-randomized studies. RevMan 5.4 was used for the meta-analysis. A total of five RCTs, one quasi-randomized controlled trial, and six observational studies were included. When compared with RL cannulation, BH cannulation significantly increased bacteremia (RR, 2.76, 95% CI (1.14, 6.67), p = 0.02) but showed no differences in AVF primary patency (HR, 1.06, 95% CI (0.45, 4.21), p = 0.90). There was no thrombosis reduction (RR, 0.51, 95% CI (0.23, 1.14), p = 0.10) or intervention number reduction (RR, 0.93, 95% CI (0.49, 1.80), p = 0.84) with BH. Outcomes like pain, hematoma, and aneurism could not be merged due to a lack of data, reported as medians, as well as due to different definitions. The quality in general was poor and the heterogeneity among the studies prevented us from merging the outcomes.

Effect of far-infrared therapy device on arteriovenous fistula maturation and lifespan in hemodialysis patients: a randomized controlled clinical trial.

Arteriovenous fistula (AVF) is the first choice of vascular access for hemodialysis treatment, and its surgical maturity rate is not high, and its postoperative complications (mostly stenosis) significantly shorten its life. At present, there are few studies on treatment methods to improve the maturity and survival of AVF. In this study, the effect of far infrared therapy (FIR) on the maturity and longevity of arteriovenous fistula in hemodialysis patients was discussed, and the protective mechanism of AVF induced by FIR therapy was explored, aiming at exploring a new treatment method. The hemodialysis patients admitted to the 900th Hospital of the Chinese Joint Logistics Support Force of the People's Liberation Army from January 2021 to April 2023 were randomly divided into control group and intervention group, with 40 cases in each group. Among them, the control group was coated with mucopolysaccharide polysulfonate cream; Intervention group: The patients were treated with mucopolysaccharide polysulfonate cream and far infrared radiation at the same time. After 3 months' intervention, the arteriovenous fistula (vein diameter, mature time of arteriovenous fistula, blood flow controlled by pump during dialysis, blood flow of brachial artery during dialysis and the occurrence of complications of internal fistula (oozing, occlusion and infection) and the pain score (numerical rating scale, NRS) of the two groups were compared, and the curative effects were compared. There was no significant difference in general data between the two groups (P > 0.05), which indicated that the study was comparable. After 3 months' intervention, the vein diameter, pump-controlled blood flow and brachial artery blood flow in the intervention group were significantly higher than those in the control group (P < 0.05). And the maturity time, NRS score and complication rate of arteriovenous fistula were significantly lower than those of the control group (P < 0.05). The primary patency rate of AVF in the intervention group was higher than that in the control group, and the overall patency rate between the two groups was statistically significant (P < 0.05). As a promising new treatment method, far infrared therapy can effectively promote the maturity of AVF, increase venous diameter, pump controlled blood flow during dialysis, brachial artery blood flow during dialysis, and prolong the service life of AVF.

Association of vitamin D metabolites with arteriovenous fistula function in hemodialysis patients: A single center study.

Arteriovenous fistula (AVF) is a primary dialysis vascular access commonly used for maintaining hemodialysis (MHD) patients. Vitamin D (VD) is a fat-soluble steroid hormone that is closely related to vascular endothelial function. This study aimed to investigate the association between VD metabolites and AVF failure in patients undergoing HD. This study included 443 HD patients using AVF between January 2010 and January 2020. The AVF operations in these patients were newly created by the same physician. We analyzed the AVF patency rates using the chi-square test. Univariate and multivariate logistic regression analyses were performed to explore risk factors for AVF failure. Survival analysis was performed to explore AVF survival at different serum 25-hydroxyvitamin D (25(OH)D) concentrations. Logistic regression analyses showed that male sex; age; BMI; serum albumin, triglyceride, phosphorus, 25(OH)D, iPTH and hemoglobin levels, history of hypertension, CHD, diabetes, stroke, and antiplatelet drug use; and smoking habits were not risk factors for AVF failure. The failure incidence rates of AVF in subjects in the VD deficiency and non VD deficiency group were not statistically significant (25.0% vs. 30.8%, p=0.344). The AVF failure incidence rates at 1, 3, and 5 years in the patients with 25(OH)D levels more than 20 ng/mL were 26%, 29%, and 37%, respectively, and the one-year AVF failure incidence rates were 27% in the patients with 25(OH)D levels less than 20 ng/mL. In addition, the Kaplan-Meier analysis suggested that the no significant differences were noted when calculating the cumulative survival rates of AVF between the two groups within 50 months of AVF using. Our findings suggest that 25(OH)D deficiency is not associated with AVF failure incidence rates, and that 25(OH)D deficiency has no significant impact on long-term cumulative AVF survival rate.

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.

A randomised control trial protocol of MuST for vascular access cannulation in hemodialysis patients (MuST Study): contributions for a safe nursing intervention

BackgroundThe vascular access preservation and the maintenance of a complication-free fistula remains an Achilles’ heel of hemodialysis in chronic kidney patients due to its substantial contribution to the morbidity and mortality. Systematic studies in the area of examining cannulation practices, achieving complication-free cannulation, and strategies to improve fistula survival are needed. For this reason, we consider it essential to create and investigate new methodologies for approaching fistula in patients on regular HD.The Multiple Single Cannulation Technique (MuST) is based on the association between the rope-ladder (RL) using the arteriovenous vessel through progressive rotation, and the buttonhole (BH) since there are three specific cannulation sites for each cannulation day during the week. The MuST is simple to implement and seems to be a very promising technique in terms of patient safety. Previous studies already showed an arteriovenous fistula survival similar to RL but significantly higher than BH.MethodsThis MuST study is a multicenter, prospective, non-blind, parallel-group, randomized controlled trial with the intervention group submitted to MuST and a control group undergoing the rope-ladder, up to 100 subjects for each group. Patients will be randomized 1:1 to one of two cannulation technique (CT), and the follow-up period of this study will be 12 months. Primary outcome is to evaluate the arteriovenous fistula survival rate at 12 months determined by the percentage of fistulas in use from the beginning of the study to the date of the first clinical intervention by angioplasty or vascular surgery, to maintain or restore patency (unassisted patency). Secondary outcome is to evaluate arteriovenous fistula survival rate at 12 month determined by the percentage of fistulas in use from the study start to the date of access abandonment due to dysfunction, patient abandonment, or death, treatment change modality or study end. We will also evaluate the assisted primary patency and include the following secondary outcomes associated with the cannulation technique: Infection, Hematoma, Aneurysm development, and pain.DiscussionThe study will investigate whether fistula survival can be improved when using cannulation by MuST compared to the RL. MuST study will provide important information on fistula survival when cannulated by MuST but also information related to its use in fistulas previously cannulated by other CTs.Trial registrationClinicalTrials.gov identifier NCT05081648 registered on 18 October 2021.

MO790: Arteriovenous Fistula Calcifications—Risk Factors and Impact on Arteriovenous Fistula Functionality

Abstract BACKGROUND AND AIMS Vascular calcifications have been recognized as frequent findings in patients with end-stage renal disease (ESRD) and have intricate mechanisms, including chronic kidney disease—mineral and bone disorders (CKD-MBD), inflammation and advanced atherosclerosis. The pathogenesis of arteriovenous fistula (AVF) calcifications is not fully understood, since it involves many other factors related to haemodialysis (HD) such as haemodynamic variables or vessel wall shear stress. The current study aims to assess the risk factors related to AVF calcifications and the impact on AVF functionality. METHOD The study included 174 chronic HD patients, mean age 58 ± 12 years, 35% female, median AVF duration 44 ± 52 months, with 35.9% radio-cephalic AVF, 12.1% brachio-basilic AVF, 52% brachio-cephalic AVF. The same nephrologist performed Doppler and B-mode AVF US scans in order to record AVF calcifications (defined as areas of hyperechogenicity with or without posterior shadowing within the arterial wall), as well as other complications (stenosis, partial thrombosis, aneurysms). In the same month of the AVF ultrasound assessment, cardiac echocardiography was performed in order to assess valvular calcifications. Laboratory parameters were analysed in the same month (Hb, calcium, phosphorus, serum bicarbonate, iPTH, albumin, ferritin, CRP). Dialysis efficiency (mean eKt/V in the month of ultrasound assessment) was recorded. The AVF survival was followed for 1 year after the initial evaluation, or up to the patient's death/transplantation. Statistical analysis was performed using MedCalc 14.8.1.0. RESULTS In our group, we found that the prevalence of AVF calcifications was 38% (66/174). Significantly more radiocephalic AVFs (47%) had calcifications than brachio-cephalic (38%) or brachio-basilic AVFs (15%), P = 0.04. The presence of calcifications was associated with longer AVF duration (P &amp;lt; .001), the presence of concomitant AVF stenosis (P = .04) and lower Hb levels (P = .02). The presence of AVF calcifications was not significantly associated with age, cardiac calcifications, or the presence of diabetes mellitus. Moreover, there was no statistically significant difference between the eKT/v values obtained in the group with AVF calcifications versus without AVF calcifications. We used the Cox proportional hazards model adjusted for standardized predicted values to determine whether patients with AVF calcifications had an increased risk of AVF failure. We found that after 1 year, 18,1% AVFs with calcifications had failed (12/66) while only 4.6% AVFs without calcifications had failed (5/108) [P = 0.02, hazard ratio (HR) 3.5, 95% confidence interval (95% CI) 1–11.3]. CONCLUSION The prevalence of AVF calcifications was 38% and affects radio-cephalic AVFs the most. AVF calcifications detected through ultrasound represent a risk factor for AVF failure, but the mechanism might be different from the pathways engaged in other vascular calcifications associated with CKD. We found no correlation with concomitant cardiac calcifications or CKD-MBD related biochemical changes. We found that AVF calcifications rather associate with HD-related factors (longer AVF duration and the presence of AVF stenosis). We suggest that periodic screening via ultrasound may be an easy method to diagnose AVF calcifications.

Bridge of Tunneled Cuffed Catheter as a Risk for Future Arteriovenous Fistulae Failure.

Background: A clinically tunneled cuffed catheter (TCC) for hemodialysis (HD) is often inserted into end-stage renal disease patients, who have an immature or no arteriovenous fistula (AVF), for the performance of HD to relieve uremic syndrome or to solve uncontrolled fluid overload, hyperkalemia, or metabolic acidosis. The catheter is primarily regarded as a bridge until the AVF matures and can be cannulated for HD. However, the effect of the bridge of the TCC on the future patency of AVFs remains elusive. Methods: This nationwide population-based observational study compared the hazards of AVF failure and the time to AVF failure. We enrolled 24,142 adult incident patients on HD, who received HD via AVFs for at least 90 days between 1 January 2010 and 31 December 2015. The subjects were divided into two groups, according to the history of TCC, and were followed-up until the failure of the AVF, mortality, or the end of the study. A propensity score-matched analysis based on 1:1 matching of age, sex, and baseline comorbidities was utilized to reduce bias and confounding variables. Results: A Kaplan–Meier survival curve revealed that patients with and without a history of TCC had significantly better AVF survival rates (log-rank test; p < 0.001). A history of TCC was independently associated with a higher risk of new AVF or AVG creation due to AVF failure, after the adjustment of the Charlson comorbidity index score (corresponding adjusted hazard ratios of 2.17 and 1.52; 95% confidence intervals of 1.77–2.67 and 1.15–1.99). For the impact of time on AVF failure, patients with a TCC bridge had a significantly higher incidence of new AVF creation during the first year after the AVF cannulation. Conclusion: A history of a TCC bridge was an independent risk factor for AVF failure and the time of AVF failure was significantly higher during the first year after the fistula cannulation in the TCC bridge group.

Impact of Previous Tunneled Vascular Catheters and their Location on Upper Limb Arteriovenous Fistula Function.

Long-term arteriovenous fistula (AVF) survival has been shown to be adversely affected by the presence of previous tunneled vascular catheters (TVC). We analyzed the effect of previous TVCs and their location (ipsilateral versus contralateral) on the successful function of upper-limb AVFs in the first 12 months after creation. We retrospectively reviewed clinical data on patients' first upper-limb AVFs, created between January 2013 and December 2017. We analyzed the rates of successful AVF function (successful cannulation using two needles for ≥50% sessions over a 2-week period) at 6 and 12 months after creation, time to AVF maturation, and rates of assisted maturation. In total, 287 patients with first AVFs were identified, of which 142 patients had a previous TVC (102 contralateral, 40 ipsilateral) and 145 had no previous TVC. The no TVC group had higher rates of AVF function at both 6 months (69% versus 54%, OR, 1.84; 95% CI, 1.00 to 3.39, P=0.05) and 12 months (84% versus 64%, OR, 3.10; 95% CI, 1.53 to 6.26, P=0.002) compared with the TVC group. The contralateral TVC group had higher rates of AVF function at 6 months (60% versus 40%, OR, 2.21; 95% CI, 1.01 to 4.88, P=0.05), but not at 12 months (66% versus 58%, OR, 1.42; 95% CI, 0.62 to 3.25, P=0.40) compared with the ipsilateral TVC group. The median time to AVF maturation in the contralateral and ipsilateral TVC groups were 121.5 and 146 days respectively (P=0.07). Assisted maturation rates were lower in no TVC group compared with the TVC group (12% versus 28%, P=0.007), but similar between the contralateral and ipsilateral TVC groups (29% versus 26%, P=0.74). Previous TVC use was associated with poorer AVF function at 6 and 12 months, with a higher rate of assisted maturation. The presence of an ipsilateral TVC was associated with lower successful AVF use at 6 months, compared with contralateral TVC.

Cannulation Technique of Vascular Access in Haemodialysis and the Impact on the Arteriovenous Fistula Survival: Protocol of Systematic Review.

Background: Based on a literature review of various studies, comparisons between BH and RL are inconclusive regarding some outcomes. However, in the last 5 years, some studies have been published that may contribute to clarifying which cannulation technique (CT) allows better fistula survival. Aim: To review which cannulation technique allows better primary patency of the arteriovenous fistula in haemodialysis patients. Methods: We will include all randomised controlled trials and observational studies that include comparisons among CTs and thus define the benefits and risks of each CT. A PRISMA-compliant systematic review and meta-analysis will be performed in accordance with the quality and homogeneity of studies. A comprehensive search strategy will be applied to the CINAHL, MEDLINE and Embase electronic databases from January 2000 to September 2021. The primary outcome is the arteriovenous fistula primary patency. To assess the risk of bias in randomised controlled trials or quasi-experimental studies, we will use the tool Revised Cochrane Risk-of-Bias Tool for Randomized Trials (RoB 2). For nonrandomised studies, the Risk of Bias In Non-Randomized Studies of Interventions (ROBINS-I) will be used. Discussion: The evidence generated from this systematic review of current evidence could inform the design and implementation of continuous quality improvement programs in cannulation techniques in haemodialysis patients, as well as contributing to improving the curricula within haemodialysis courses. This protocol was registered with the National Institute for Health Research PROSPERO database prior to commencement (registration number CRD42021237050).

Hemodialysis Patients with Higher Serum Levels of Soluble Receptor for Advanced Glycation End Products Have an Increased Risk for Arteriovenous Fistula Failure

Background: Arteriovenous fistula (AVF) failure due to thrombosis is a major cause of morbidity in patients undergoing regular hemodialysis (HD). Advanced glycation end products (AGEs) and their receptor (RAGE) might contribute to inflammation, neointimal hyperplasia, and thrombosis. RAGE has a C-truncated secretory receptor form, called soluble RAGE (sRAGE). In this study, we aimed to evaluate the association of serum sRAGE with AVF failure due to thrombosis in HD patients. Methods: Eighty-eight prevalent HD patients with functional AVF were included in the study. The presence of stenosis, clinical and laboratory data, and serum sRAGE was evaluated at inclusion. sRAGE concentration was measured by a competitive enzyme-linked immunosorbent assay, and stenosis was detected by ultrasound. Patients were prospectively followed up for 36 months. During this period, AVF failure (defined as the absence of blast or palpable thrill and impossible cannulation with 2 needles because of complete thrombosis) was noted and thrombosis was certified by ultrasound examination. Results: During follow-up, 16 (18.18%) patients lost their vascular access due to thrombosis. In multivariate Cox regression analysis, sRAGE was a significant predictor of vascular access thrombosis (hazard ratio = 1.15, 95% confidence interval: 1.03–1.25, p = 0.012). Kaplan-Meier analysis showed a significantly lower AVF patency time in patients with sRAGE >16.78 ng/mL than those with sRAGE <16.78 ng/mL (p = 0.02). In the subgroup of patients with stenosis at baseline, sRAGE, serum albumin, obesity, and ischemic heart disease were associated with thrombosis. Conclusion: In our study, baseline, systemic sRAGE is associated with the occurrence of thrombosis of AVF, and this marker has a significant impact on AVF survival.

Maturation and survival of arteriovenous fistula: The challenge starts from the preoperative assessment stage.

It is necessary to assess the association between the preoperative indicators and the maturation and survival of arteriovenous fistula (AVF). We retrospectively identified 236 patients with a new AVF created between 2016 and 2018 in our Dialysis Center. Multivariate Logistic regression showed that preoperative arterial diameter (odds ratio [OR] = 1.452, 95% confidence interval [CI] [1.233, 1.710], p < 0.001), preoperative venous diameter (OR = 1.296, 95% CI [1.166, 1.477], p < 0.001), left ventricular ejection fraction (LVEF) (OR = 1.187, 95% CI [1.103, 1.277], p < 0.001), and diabetes mellitus (OR = 0.245, 95% CI [0.107, 0.560], p = 0.01) were independent influential factors for AVF maturation. Two years after the AVF surgery follow-up, multivariate Cox proportional-hazards model showed that the preoperative arterial diameter (OR = 0.510, 95% CI [0.320, 0.813], p = 0.005), preoperative venous diameter (OR = 0.940, 95% CI [0.897, 0.985], p = 0.010) and diabetes mellitus (OR = 1.785, 95% CI [1.117, 2.855], p = 0.016) was prognostic factors of AVF survival. The Kaplan-Meier method showed that the primary survival of AVF in patients with different preoperative arterial diameter was statistically significant (log-rank χ2 = 15.415, p < 0.001), while the secondary survival was not statistically significant (log-rank χ2 = 0.131, p = 0.717). In our cohort, the preoperative arterial and venous diameter and diabetes mellitus were independent influential factors for AVF maturation and prognostic factors of AVF survival. However, the preoperative LVEF only associated with the maturation of AVF. Meanwhile, smaller arterial diameter (≤2.15 mm) was associated with AVF maturation failure, but did not impact secondary survival of AVF.

ESR, CRP, and failure of Arterio-Venous Fistula (AVF)

Background: The survival of arteriovenous fistula (AVF) remains an important problem for hemodialysis patients, accounting for 20% of all hospitalizations related to AV access problems in western countries. We designed an observational prospective cohort study on 265 AVFs and evaluated their results after 4 months of fistula creation and its relation to laboratory tests as ESR and CRP levels. Methods: Wrist or antecubital AVFs were created for patients with End-Stage renal disease. All laboratory tests (ESR and CRP) were checked quantitatively. The patients were followed-upfor at least 4 months and failure or maturation of AVFs were recorded in a checklist. Results: 177 (66.8%) males and 88 (33.2%) females were included. The surgeon created 161(60.8%) wrist and 98 (37%) antecubital AVFs. The mean age of patients was 53.18±17.1, ranged from 8 to 91 years old. CRP and total protein had significant differences between the two groups of failure and mature accesses (0.029 and 0.045 respectively). Conclusion: High CRP level is recognized as a reliable predictor for the survival of AVF.

Stable incidence and survival of arteriovenous fistulas over 39 years: A long-term national cohort study.

The age and number of comorbidities in the hemodialysis population has increased over time. This may influence the construction and survival of the arteriovenous fistula (AVF). The present study explored the incidence and survival of AVFs over a period of 39 years. A retrospective cohort study was conducted based on Danish registries. Incident hemodialysis patients between 1977 and 2015 were included. The incidence of AVF and factors associated with the construction of an AVF were described. Risk factors for AVF survival and repair were explored by Kaplan Meier and Cox proportional hazard analysis. The total number of arteriovenous accesses (AVF and arteriovenous grafts) were 10,187 and there were 4201 central venous catheters (CVC). No significant difference in the proportion of AVFs during the 39 years was seen. Age and renal diagnosis did not influence the proportion of AVFs. Patients with CVCs were found to have a significantly higher prevalence of comorbidities (p < 0.01). AVF survival remained stable during the 39 years. The first constructed AVF had the best survival, 35% still functioning after 15 years. Factors such as brachiocephalic AVF, female sex, and diabetic nephropathy increased the risk of AVF failure (Odds Ratio (OR): 2.46, 95% Confidence Interval (CI) (2.29-2.65), 1.17 (1.10-1.25), and 1.21 (1.12-1.3)), respectively. Despite an older dialysis population, the proportion and survival of the AVF in the Danish dialysis population has not changed, probably because of increased awareness of AVF as the first choice of vascular access and improved surveillance, surgery, and repair.

Arteriovenous fistula formation with adjuvant endovascular maturation

BackgroundThe clinical utility of the native arteriovenous fistula (AVF) has been limited by the prolonged time required for maturation, the low overall maturation rate, and subsequent abandonment. Endovascular intervention has been increasingly accepted as the first-line therapy for AVF stenosis. The objective of the present study was to evaluate the AVF formation outcomes when early endovascular intervention was selectively performed to bring about timely AVF maturation. MethodsWe performed a retrospective study (February 2014 to February 2020) of 82 AVF consecutive patients (mean age, 62.5 ± 13.5 years; range, 17-83; 58 men [70.7%]) with end-stage renal failure who had undergone vascular access construction at a single institution. The 4-year AVF patency, vascular diameters, hemodialysis parameters, reintervention rate, and mortality were analyzed. ResultsRadiocephalic AVF was the most common fistula constructed (71 patients; 88.6%). The evaluation at a mean of 46.2 ± 56.0 days (range, 5-343 days) after AVF formation revealed 33 immature AVFs (40.2%). Subsequently, 19 patients had undergone endovascular procedures, including angioplasty and/or stenting of the juxta-anastomosis, cannulation zones, and/or outflow segments to bring about timely maturation of the AVF. Hence, 93.9% of the AVFs had reached functional patency (maturation) by 6 months after formation, with a mean time to maturation of 67.8 ± 65.9 days (range, 5-320 days). After reaching maturation, the primary access functional patency was 82% ± 4.3% at 6 months, 58% ± 5.5% at 12 months, and 34% ± 6.8% at 48 months. The primary assisted access functional patency was 95% ± 2.4% at 6 months, 90% ± 3.3% at 12 months, and 83% ± 4.7% at 48 months. A total of 121 endovascular interventions were performed to maintain patency, equating to an endovascular reintervention rate of 0.37 procedure/patient year. The mean arterial, venous, and brachial flow rates did not change significantly after maturation with a mean AVF (primary assisted functional patency) survival time of 5.9 ± 0.26 years (range, 5.33-6.36 years) from maturation. Only 12 thromboses had occurred after the first follow-up review after AVF formation. These were all salvaged using endovascular techniques, leading to 100% total secondary functional patency at 4 years. The 5-year estimated all-cause mortality was 45.6% ± 12.7%. ConclusionsThe AVF maturation rate and interval to maturation were improved when early endovascular intervention was selectively performed after AVF formation. This allowed for near universal maturation. In addition, once matured, the use of ongoing endovascular reinterventions allowed for a low reintervention rate and long-term patency, providing reliable long-term renal vascular access.