Numerous studies have identified the fistula as the best access for hemodialysis with fewest complications. The radiocephalic fistula (RCF) is the first access of choice, but often results in poor maturation. Therefore, an increased number of brachiocephalic fistulas (BCF) have been placed. Cephalic arch stenosis (CAS) can occur in patients with fistula access. The current study was done to determine the incidence and associated comorbidities in patients with BCF or RCF who have CAS. A retrospective review of 450 hemodialysis patients in 3 outpatient hemodialysis units between July 1, 2000 and July 1, 2005 (60 months) was preformed. We reviewed demographics, medications, and indications for venograms. Interventional Radiologists reviewed the venograms for evidence of CAS. Radiology reports were screened to determine incidence of thrombosis, treatment with either angioplasty or stent placement and if a complication such as venous rupture occurred. One hundred and twenty-seven patients had fistula access with at least 1 venogram. Of these, 30 were RCF and 97 were BCF. Cephalic arch stenosis occurred in 77% of patients with BCF and in 20% of patients with RCF. Those with diabetes had a lower rate of occurrence than those without (p<0.01). Cephalic arch stenosis led to a high rate of thrombosis (p<0.01). The probability of having multiple radiology procedures was higher with CAS than without (p<0.01). Cephalic arch stenosis is an important problem in hemodialysis patients who have fistula access, and contributes to thrombosis. Diabetes was found to have a negative association with CAS for undefined reasons. Attempts to understand this relationship are important.