Maturation Rates of Arteriovenous Fistulas Utilizing Small Veins in the Era of Endovascular Interventions.

Abstract Objective Traditional practice suggests the abandonment of veins smaller than 3 mm in diameter for arteriovenous fistula (AVF) creation, because of low rate of maturation. This study aims to show that with Balloon Assisted Maturation (BAM), undersized veins can be used to create functional AVFs with a high rate of success. Methods All patients who underwent AVF creation between 2014 and 2018 at a tertiary academic medical center were retrospectively reviewed. The patients without pre-operative vein mapping, those who failed to follow-up and the patients who were not on dialysis were excluded. A fistula was considered to be mature if it was successfully cannulated for dialysis. 596 patients were identified for analysis. The cohort was divided into small vein group (SVG, Results In the study cohort, 61.9% of the patients were male, with an average age of 62.8±13.7 years, and an average pre-operative vein size of 2.9±1.1mm. With similar demographic distribution, the subjects in SVG (n=216) had significantly smaller pre-operative vein size of 1.9 ±0.4 mm, than the patients in LGV (n=380), 3.5± 0.8 mm (p=0.001). There were significantly more radio-cephalic AVFs created in SVG (77.8% vs. 48.7%, p The overall maturation rate was 83.1% (n=495), 219 fistulas (36.7%) matured primarily and 276 (46.3%) required interventions. Ninety-one percent of the patients required only 1 or 2 BAMs to achieve maturation. SVG achieved a maturation rate of 75.9% as compared to 87.1% in LGV (p=0.002). A significantly higher number of patients in SVG required BAM for maturation as compared to LVG (67.7% vs. 49.9%, p=0.0002); however, there was no difference in the average number of BAMs required for fistula maturation between the groups (1.5 ± 0.8 for SVG vs. 1.4 ± 0.7 for LVG). In multivariable logistic regression analysis, vein size ≥2.5 mm (OR=2.11, CI:1.36-3.27, p=0.0009) and male sex (OR=2.30, CI:1.49-3.57, p=0.0002) were independent predictors of maturation. Conclusion Small veins can be used for AVF creation with lower but still favorable maturation rates utilizing BAM interventions, especially in male patients. This practice can increase the creation of autogenous dialysis access and potentially reduce complications related to prosthetic dialysis access.