Functional patency rates of arteriovenous fistula of a retrospective cohort study from one of the biggest centers in Canada

BackgroundThe main barriers to arterio-venous fistula (AVF) utilization are primary failure, long maturation duration, and low secondary patency rates.MethodsIn this retrospective cohort study, primary, secondary, functional primary, and functional secondary patency rates were calculated and compared between two age groups (< 75 years and > = 75 years) and between radiocephalic (RC-) and upper arm (UA-) AVFs, and factors determining the duration of functional secondary patency were evaluated.ResultsBetween 2016 and 2020, 206 predialysis patients whose AVFs had been created previously initiated renal replacement treatment. RC-AVFs comprised 23.3% and were created after favorable analysis of the forearm vasculature. Overall, the primary failure rate was 8.3, and 84.7% started hemodialysis with a functioning AVF. Functional secondary patency rates of primary AVFs were better with RC-AVFs [1,3 and 5 year rates of 95.8, 81.9 and 81.9% versus 83.4, 71.8 and 59.2% for UA-AVFs (log rank p: 0.041)]. There was no difference between the two age groups for any of the AVF outcomes assessed. Among patients whose AVF was abandoned, 40.3% had gone on to have a second fistula created. This was significantly less likely in the older group (p < 0.01). In conclusion: (1) UA-AVFs were placed more commonly than RC-AVFs; (2) a selection bias existed whereby RC-AVFs were only created after favorable forearm vasculature was demonstrated or suspected; (3) superior functional secondary patency rates were observed with RC-AV's, perhaps stemming from this selection bias; (4) the elderly were more likely to have only one AVF creation attempt.