# Endovascular Salvage of Native Arteriovenous Fistulas in Hemodialysis Patients: Assisted Primary Patency Outcomes of a Single-Center Study

## TL;DR

This study examines the success of endovascular salvage procedures in restoring native arteriovenous fistulas for hemodialysis patients in a Colombian hospital.

## Contribution

The study provides patency outcomes of endovascular salvage in a resource-limited setting, highlighting its effectiveness.

## Key findings

- Primary assisted patency rates were 95%, 67%, and 63% at one, six, and 12 months, respectively.
- Radiocephalic fistulas showed a 100% patency rate at 12 months, while brachiobrachial fistulas had a 33% rate.

## Abstract

Introduction: Patients with end-stage kidney disease (ESKD) on hemodialysis (HD) require a functional vascular access, of which the best option is a native arteriovenous fistula (AVFn). These fistulas may fail due to multiple factors, which may delay HD, and salvage endovascular interventions are indicated to restore fistula patency. Given the increasing incidence of ESKD, it is essential to describe demographic and clinical characteristics of patients with AVFn, as well as their patency outcomes after the first salvage intervention. The purpose of this study is to evaluate the assisted primary patency at one, six, and 12 months in a third-level hospital in Colombia.

Methods: We conducted a retrospective cross-sectional study to characterize patients undergoing endovascular salvage of arteriovenous fistulas (AVFs) and describe assisted patency at one, six, and 12 months. Our study included patients treated between January 2023 and June 2025 at the Hospital Departamental de Villavicencio, a tertiary-level hospital and regional referral center in Colombia. Exclusion criteria included patients with prior open surgical salvage, undetermined procedural success, or incomplete medical records. Data were obtained from electronic medical records, which included demographic, clinical, and procedural characteristics. Descriptive statistics were performed using RStudio (RStudio, PBC, Boston, MA).

Results: A total of 43 patients were included in the study (mean age 59 years, 70% male). Hypertension was the leading cause of ESKD (38, 88%) and the most frequent comorbidity (42, 98%). Thrombosis was the main cause of AVFn dysfunction (34, 79%). Most fistulas were brachiocephalic (32, 74%) and left-sided (26, 60%). The median time from dysfunction to salvage was 8 days. Angioplasty was performed in 42 patients (98%), followed by thrombectomy in 22 (51%), stent placement in 12 (28%), and thromboaspiration in 12 (28%). Primary assisted patency at one, six, and 12 months was observed in 41 (95%), 29 (67%), and 27 (63%) patients, respectively. Radiocephalic fistulas showed the best performance, with a 12-month patency rate of 100% (4/4), whereas brachiobrachial fistulas showed the lowest rate at 33% (1/3). Statistical analysis demonstrated no significant associations between anatomical site, previous CVC placement, thrombosis risk factors, or previously documented thrombosis and patency at one, six, and 12 months.

Conclusions: Our results highlight the promising results of salvage procedures for AVF in patients undergoing HD, even in a resource-limited setting, demonstrating adequate assisted primary patency duration. More robust prospective studies are needed to validate our findings and to identify prognostic factors associated with long-term AVF patency after endovascular salvage. Additionally, it is critical to develop surveillance protocols focused on fistula research and care, as well as the development of institutional guidelines.