Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 64 3 2026 05 20 170 178 Roozbeh Cheraghali Vascular and Endovascular Surgery Department, Sina Hospital, Tehran University of Medical Sciences, Tehran, Iran Sepide Javankiani Department of General Surgery, Tehran University of Medical Sciences, Tehran, Iran Yasin Alipour Students’ Scientific Research Center, Tehran University of Medical Sciences, Tehran, Iran Seyed Amir Miratashi Yazdi Department of Surgery, Sina Hospital, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran 2025 08 03 2025 11 02 Introduction: The survival of arterio-venous (AV) fistula and the high rate of hospitalization of these patients (about 20% of the hospitalizations of these patients) are one of the most important challenges of the health system in the management of ESRD patients all over the world. Since AVF failure increases the mortality of patients and causes an increase in treatment costs, determining the optimal site (distal radiocephalic vs. antecubital brachiocephalic) as well as patient factors influencing functional success is crucial. Methods: This observational study was conducted in 2022 on ESRD patients, candidates for hemodialysis who underwent fistula bypass surgery in a tertiary center. Fifty patients we enrolled in the distal radiocephalic fistulas (DRF) groups, and 50 received antecubital brachiocephalic fistulas (ACBF). Demographic characteristics of the patients, such as age, gender, history of diabetes, high blood pressure, and smoking, were recorded. The primary outcome was AVF maturation at 120 days (functional vs. failed). A secondary outcome was early failure, defined as the absence of bruit or thrill within 30 days. Results: 100 patients were examined in two groups (according to the location of the fistula), and the average age was reported as 52.4 ± 12.5. AVF failure was reported in 38% of patients, of which 26% occurred within the first 30 days and 12% occurred within 30 to 120 days. The AVF failure rate was similar between DRF and ACBF groups (P value: 1.00).  No statistically significant difference was seen for the failure rate of fistulas based on gender (P value: 0.715).  In adjusted analysis, each additional year of age increased the odds of maturation by 4.3% (OR 1.043, 95% CI 1.004–1.083; P value = 0.029), and hypertension was independently associated with higher maturation odds (OR 2.747, 95% CI 1.119–6.746; P value = 0.027). For early failure (<30 days), female patients had 4.7-fold higher odds of failure than males (OR 4.676, 95% CI 1.556–14.048; p = 0.006), while other covariates showed no significant associations. Conclusion: This study examined the factors that contribute to the failure of arteriovenous fistulas in ESRD patients who are eligible for hemodialysis. The findings demonstrated that various factors, including age and history of hypertension, can affect its success rate. These results are congruent with previous articles and emphasize the importance of choosing the correct type of fistula and careful management of risk factors in improving treatment. https://acta.tums.ac.ir/index.php/acta/article/view/11751 https://acta.tums.ac.ir/index.php/acta/article/download/11751/6036