Objective
Arteriovenous fistulas (AVF) are considered superior to arteriovenous grafts (AVG) because of longer secondary patency after successful cannulation for dialysis. We evaluated whether access interventions before successful cannulation impact the relative longevity of AVF and AVG after successful use.
Methods
This retrospective study of a prospective database identified patients who initiated dialysis with a catheter, and subsequently had a permanent access (289 AVF and 310 AVG) placed between 1/1/06-12/31/11 and successfully cannulated for dialysis at a large medical center. Patients were followed until 6/30/14, and we evaluated the clinical outcomes (secondary patency and frequency of interventions) of the vascular accesses.
Results
An intervention before successful cannulation was required more frequently with AVF than with AVG (50.5 vs 17.7%; OR 4.74; 95% CI 3.26 to 6.86, P < .0001). As compared to AVF that matured without interventions, those that required intervention had shorter secondary patency after successful cannulation (HR 1.84; 95% CI 1.30–2.60, P < .0001) and required more interventions per year after successful use (RR 1.81; 95% CI 1.49–2.20, P < .0001). Similarly, AVG that required intervention before successful cannulation had shorter secondary patency than those without prior intervention (OR 1.98, 95% CI 1.52 to 4.02, P < .0001) and required more interventions per year after successful use (RR 1.49; 95% CI 1.27–1.74, P < .0001). AVF requiring intervention before maturation had inferior secondary patency as compared to AVG that were cannulated without prior intervention (HR 1.45, 95% CI 1.08 to 2.01, P = 0.01), but required fewer annual interventions after successful use (RR 0.57; 95% CI 0.49–0.66, P < .0001).
Conclusions
The patency advantage of AVF over AVG is no longer evident in patients requiring an AVF intervention prior to successful cannulation, but the AVF require fewer interventions after successful use.