Long-Term Outcomes of Arteriovenous Fistulas with Unassisted versus Assisted Maturation: A Retrospective National Hemodialysis Cohort Study

Significance Statement Before successful use in dialysis, many arteriovenous fistulas (AVFs) require one or more endovascular or surgical interventions to assist clinical maturation. However, the effect of assisted maturation on long-term postmaturation AVF outcomes is poorly studied. In this retrospective analysis, the authors analyzed the US Renal Data System to identify elderly patients who underwent AVF creation after initiation of hemodialysis, and whose AVF was used successfully for dialysis with or without assisted maturation. Their analysis of the relationship between the number of prematuration AVF interventions and postmaturation AVF outcomes found a positive association between the number of prematuration interventions and the likelihood of primary patency loss and frequency of interventions after maturation. These findings highlight the high burden of costly interventions to assist clinical maturation for successful AVF use. Background About half of arteriovenous fistulas (AVFs) require one or more interventions before successful dialysis use, a process called assisted maturation. Previous research suggested that AVF abandonment and interventions to maintain patency after maturation may be more frequent with assisted maturation versus unassisted maturation. Methods Using the US Renal Data System, we retrospectively compared patients with assisted versus unassisted AVF maturation for postmaturation AVF outcomes, including functional primary patency loss (requiring intervention after achieving AVF maturation), AVF abandonment, and frequency of interventions. Results We included 7301 patients ≥67 years who initiated hemodialysis from July 2010 to June 2012 with a catheter and no prior AVF; all had an AVF created within 6 months of starting hemodialysis and used for dialysis (matured) within 6 months of creation, with 2-year postmaturation follow-up. AVFs matured without prior intervention for 56% of the patients. Assisted AVF maturation with one, two, three, or four or more prematuration interventions occurred in 23%, 12%, 5%, and 4% of patients, respectively. Patients with prematuration interventions had significantly increased risk of functional primary patency loss compared with patients who had unassisted AVF maturation, and the risk increased with the number of interventions. Although the likelihood of AVF abandonment was not higher among patients with up to three prematuration interventions compared with patients with unassisted AVF maturation, it was significantly higher among those with four or more interventions. Conclusions For this cohort of patients undergoing assisted AVF maturation, we observed a positive association between the number of prematuration AVF interventions and the likelihood of functional primary patency loss and frequency of postmaturation interventions.