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Flow Reduction for the Treatment of Recurrent Cephalic Arch Stenosis in Brachiocephalic Hemodialysis Arteriovenous Fistulas

Brachiocephalic fistulas are much more likely to develop cephalic arch stenoses than other types of fistulas (1, 2). Cephalic arch stenosis (CAS) has been implicated in 2% of radiocephalic and 39% of brachiocephalic fistula failures (1). Stenoses at the cephalic arch have been found to be resistant to angioplasty (2) and it has been suggested that high flow is a major cause of venous intimal hyperplasia (3, 4). Banding is a technique that has commonly been used to reduce flow in hypervolemic accesses. The Minimally Invasive Limited Ligation Endoluminal-assisted Revision (MILLER) is a method of banding that uses intraluminal angioplasty balloons to precisely adjust the size of the band and does not require open surgery (5). Banding has previously been used to treat venous intimal hyperplasia in arteriovenous grafts. Fillinger et al. (6) has demonstrated that banded grafts have lower rates of venous intimal hyperplasia than unbanded grafts, suggesting that a significant reduction in flow results in a decrease in venous intimal hyperplasia. We are presenting a study that examines the effect of fistula flow reduction on recurrent CAS. A retrospective analysis of patients who had undergone the MILLER banding procedure (5) to treat Steal syndrome and hypervolemic accesses was conducted. The patient inclusion criterion was recurrent CAS prior to the time of banding, defined as 3 or more percutaneous interventions (angioplasty / stent) at the cephalic arch within 6 months. A paired t-test was used to evaluate the effect of MILLER banding on the frequency of interventions at the cephalic arch, with subjects serving as their own controls. 14 patients (6 male and 8 female) with brachiocephalic fistulas were included in this study. The average patient age was 59; the rate of diabetes and hypertension was 38% and 71%, respectively. The average band size was 4mm (range, 3-5mm). Flow measurements were obtained in 2 patients, and the average flow reduction was from 2713mL/min to 1235mL/min (54% reduction). The average rate of interventions at the cephalic arch was reduced from 5.4 to 1.0 per access-year following the banding procedure (paired t-test, t = 4.55, p < 0.01; Table I). The lesion patency was 83%, 71%, and 71% at 3, 6 and 12 months (Fig. 1). The secondary access patency was 100% at 12 months. The average followup time was 12 months (range, 0.25-33 months). We observed a statistically significant reduction in the rate of CAS following banding (p < 0.01). As such, we consider flow reduction to be an effective treatment for CAS. When angioplasty and stent placement fail to achieve durable cephalic arch patency, the MILLER banding procedure provides the interventionalist with an alternative treatment which is reversible and minimally invasive.