Vessel diameter and radiocephalic arteriovenous fistula: A meta-analysis and Markov model

OBJECTIVE

The aim of this study was to determine the optimal radial artery (RA) and cephalic vein (CV) diameter for the best functional maturation (FM) of radiocephalic arteriovenous fistula with their financial implication.

METHODS

A systematic review and meta-analysis following Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines included 4610 patients. The data was initially subjected to Pearson correlation to evaluate success-to-failure ratios on the endpoint of FM, to rule out the impact of confounders. This allowed for the meta-analysis using a random-effects model, assessing odds ratios (ORs) at 95% confidence intervals (CIs) relative to the line of no effect. Outcomes were subjected to Markov chain model, incorporating transition probabilities and sequential decision-making. Post-hoc analysis was performed to assess the adequacy of the sample size. This review is registered with International Prospective Register for Systematic Review (PROSPERO): CRD42022348509.

RESULTS

There was a moderate negative correlation (r = -0.44; P > .05), indicating no significant linear relationship. A CV diameter of 2 to 2.4 mm was associated with the best FM (OR, 1.29; 95% CI, 1.01-1.65; P < .04), whereas an RA diameter of 2 mm achieved an OR of 1.27 (95% CI, 0.95-1.7). The cost per arteriovenous fistula creation was £3079 for CV-based and £4285 for RA-diameter based approach. The CV diameter of 2 to 2.4 mm was the most cost-effective at £2411. Post-hoc power analysis confirmed the adequacy of the sample size with an effect size of d = 0.547 for an objective inference.

CONCLUSIONS

Superior maturation is plausible with a CV diameter of 2 to 2.4 mm and a RA diameter of 2 mm or more. Diameters below these thresholds yield poorer outcomes, whereas larger diameters provide no additional benefit.

Patency of arteriovenous fistulas and grafts for dialysis access: An analysis using the Korean National Health Insurance Service database from 2008 to 2019

BACKGROUND

Arteriovenous (AV) access practice and its outcomes vary internationally. To provide a better understanding of the patterns and outcomes of AV access creation, we investigated the patency and risk factors of arteriovenous fistulas (AVFs) and grafts (AVGs) as initial AV access in the Korean adult population using data from the last 10 years.

METHODS

The National Health Insurance Service database was queried retrospectively to identify patients undergoing hemodialysis with AVFs and AVGs as well as their clinical characteristics and outcomes from 2008 to 2019. AV access patency and its associated risk factors were evaluated.

RESULTS

During the study period, 64,179 AVFs and 21,857 AVGs were placed. The mean patient age was 62.6 ± 13.6 years (21.5% were ⩾75 years old), and 39.3% patients were women. More than half of the patients underwent AV access creation at tertiary care hospitals. At 1 year, the primary, primary assisted, and secondary patency rates were 62.2%, 80.7%, and 94.2% for AVFs, and 46.0%, 68.4%, and 86.8% for AVGs, respectively. AVG, older age, female sex, diabetes, and creation at general hospitals (vs tertiary hospitals) were associated with decreased patency outcomes (all, p < 0.05).

CONCLUSION

This study using national data showed that three quarters of patients with AV access had AVF and AVF showed superior performance to AVG and identified several patient and center factors related to AV access patency in Korea.

International survey of radiocephalic arteriovenous fistula: ISRAF survey

AIMS

The objective of this survey was to encompass the full scope of international practice, entailing all technical, non-technical, preoperative stratification and functional maturation (FM) of RCAVF.

METHODS

The survey contained n = 19 questionnaires with n = 46 variables completed by n = 85 providers from n = 21 nations across n = 5 continents. The numerical values were subjected to mean with standard error whereas the nominal data to a non-parametric (Kruskal-Wallis & Spearman correlation test) and analysis of variance (ANOVA). The test of homogeneity, & probability was reported 95% confidence intervals (CI) alongside error plots. Furthermore, a decision and higher attribute tree model was constructed based on current survey for higher FM in RCAVF.

RESULTS

FM is independently associated with volume of surgeon per year (procedures performed) (p < 0.01) [High Volume: 73% (95% CI, 68-77%) versus Average volume: 63% (95% CI, 59-66%) vs Low volume: 56% (95% CI, 51-61%)]. FM increased by 8% with every 20 more procedures per group of surgeons on end point of FM. Amongst continents: Australia, America, Asia and South America demonstrated higher FM to Africa & Europe (p < 0.05). UK possessed a lower FM 58% (95% CI, 48-68%) in comparison to the world & Europe respectively [65% (95% CI, 61-70%) vs 61% (95% CI, 58--65%)]. There was a positive causal link between angle of anastomosis at 30-76° (p < 0.01), longitudinal & S-shaped incision & arteriotomy length of 3 & 4 mm to higher FM (p < 0.05).

CONCLUSION

FM in RCAVF is independently & incrementally associated with the volume of surgeon per year. There is a diverse inclusion, exclusion and technical approach in RCAVF creation. This survey advocates the importance of international collaboration and/or registry in assimilation, consolidate and development of consensus.

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

INTRODUCTION

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.

METHODS

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.

RESULTS

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.

CONCLUSION

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.

Expert consensus on the establishment and maintenance of native arteriovenous fistula

Vascular access is the lifeline of hemodialysis patients. There are great differences in the establishment and use of vascular access in different countries and regions around the world. We believe that on the basis of good evaluation and planning, it is recommended that hemodialysis patients choose native arteriovenous fistula first. In view of the new progress of vascular access views domestic and international at home and abroad in recent years, we organized experts to recommend the establishment and maintenance of arteriovenous fistula (AVF) for the Chinese population, including preoperative evaluation and planning of the establishment of AVF, AVF surgery, perioperative drug intervention measures and postoperative maintenance, and put forward suggestions for future research directions. The recommendations in this consensus are general and clinicians need to make treatment decisions based on the actual situation.

Association of preoperative vein mapping with hemodialysis access characteristics and outcomes in the Vascular Quality Initiative

BACKGROUND

Preoperative vein mapping before arteriovenous fistula (AVF) or arteriovenous graft (AVG) placement has been debated as a possible method of improving hemodialysis access outcomes for patients. However, high-quality national studies that have addressed this relationship are lacking. Thus, we assessed the association of preoperative vein mapping with hemodialysis access configuration and outcomes.

METHODS

In the present cohort study, we analyzed all patients who had undergone AVF or AVG placement with data captured in the Vascular Quality Initiative hemodialysis access dataset from August 2011 to September 2019. The patients were stratified by whether they had undergone preoperative vein mapping. The primary (configuration) outcomes were access type (AVF vs AVG) and location (upper arm vs forearm). The secondary (longitudinal) outcomes were the successful initiation of hemodialysis, maintenance of secondary patency, and the need for reintervention 1 year after the index operation.

RESULTS

Overall, 85.6% of the 46,010 included patients had undergone preoperative vein mapping. Of the 46,010 patients, 76.1% and 23.9% had undergone AVF and AVG creation, respectively. AVF creation (77.6% vs 67.3%) and forearm location (54.6% vs 47.3%) were more frequent for the patients who had undergone preoperative vein mapping than for those who had not (P < .001). After adjusting for baseline differences between the groups, preoperative vein mapping was associated with increased odds of receiving an AVF vs AVG (adjusted odds ratio, 1.64; 95% confidence interval [CI], 1.55-1.75) and forearm vs upper arm access (adjusted odds ratio, 1.22; 95% CI, 1.16-1.30). The incidence of the loss of secondary patency was lower for patients with preoperative vein mapping (P < .001), and persisted after risk adjustment (adjusted hazard ratio, 0.81; 95% CI, 0.75-0.88).

CONCLUSIONS

Preoperative vein mapping was associated with favorable hemodialysis access configurations and outcomes in real-world practice. These data suggest that the use of preoperative vein mapping could improve the likelihood of favorable outcomes for patients requiring hemodialysis access.

Real-World Usage of the WavelinQ EndoAVF System

BACKGROUND

Dependent on existing deep to superficial perforating venous branches, the WavelinQ EndoAVF System is a novel technique used to create an arteriovenous fistula (AVF) between ulnar or radial veins and concomitant arteries for dialysis access. We sought to examine a single center's success rates and short-term follow-up using this device.

METHODS

All consecutive patients undergoing placement of a WavelinQ AVF from October 2018 to July 2019 were included. Preoperative/intraoperative variables including demographics, preoperative/postoperative duplex ultrasonography, success rate of procedure, and subsequent endovascular/surgical procedures were obtained. Descriptive statistics and comparison of groups requiring subsequent intervention were performed.

RESULTS

Thirty-five patients underwent placement of the WavelinQ AVF, with 32 (91%) patients having at least one documented follow-up. These patients were predominantly male (23/32, 72%) with an average age of 60.2 and 23 of 32 (72%) patients were on dialysis. Initial fistula creation success rate was 100%. Average procedural length was 120 min, fluoroscopy time 9.6 min, and contrast usage 52.2 mL. Eight of 32 (25%) patients had perioperative complications (3 hematomas, 3 contrast extravasations, 1 resolved vessel spasm all resolving spontaneously, and 1 pseudoaneurysm requiring surgical repair). Thirteen of 32 (41%) patients underwent subsequent endovascular interventions to assist with maturation [9/32 (28%) branch coiling, 5/32 (16%) angioplasty/stenting, and 3/32 (9%) access thrombectomy] and 4 of 32 (13%) patients required subsequent surgical interventions (1 pseudoaneurysm repair, 1 revision of fistula, and 2 definitive AVF creation in thrombosed grafts). The majority of accesses (30/32, 94%) were ulnar-ulnar fistulas and overall patency at average follow-up of 73 days was 88% (28/32) with average brachial artery inflow volume of 1,078 cc/min and average cephalic vein (18/32) outflow volume of 447 cc/min. Eleven of 23 (48%) patients on dialysis were successfully using the EndoAVF at follow-up.

CONCLUSIONS

The WavelinQ AVF system has a high initial procedural success rate, although a significant portion of patients require subsequent endovascular procedures to aid in maturation. Further work on determining factors predictive of need for reintervention is necessary.