Dialysis-Related Parameters Influence Remodeling in the Venous Part of the Native Arteriovenous Fistula.

Background: The aim of this study was to evaluate the association of hemodynamic parameters related to hemodialysis and antropometric parameters of patients with changes in the venous part of the arteriovenous fistula (AVF) at points of needling.

Methods: Two hundred forty-two hemodialysis (HD) patients (60.3% men), with median age 65 (interquartile range [IQR] 56-75) years, on HD treatment for a median of 49 (IQR 20-88) months with functioning fistula were recruited for the study. The history of vascular access, comorbidity, antropometric (body mass index, body surface area, and body composition), and dialysis-related parameters were analyzed. The cross-sectional area of upper extremity vessels were measured using ultrasound and included 2 points: A (arterial point for blood aspiration) and V (venous point for returning the blood after purification). The difference between A and V (A-V) was calculated.

Results: The median cross-sectional area of A was larger than V (1.04 [IQR 0.58-1.7] vs. 0.74 cm [IQR: 0.41-1.39], P <0.0001). The median difference between A and V (A-V) was 0.17 cm and positively correlated with mean blood flow (Qb), effective Kt/V, and time of AVF use. Other analyzed factors had no influence on A-V. In the multivariate analysis, the independent factor increasing the difference (A-V) was mean blood flow measured during HD sessions.

Conclusions: The needling and utilization of AVF for hemodialysis may affect vein anatomy, namely causing dilatation at the arterial point and narrowing at venous point of AVF. We suggest that blood pump velocity of the dialysis machine may have an impact on these changes, but practical importance of these findings has to be elucidated. The significance of (A-V) factor in the prognosis of fistula complications should be further studied and confirmed in the prospective trials.