Risk factors for the development of cephalic arch stenosis

The creation of a vascular access is necessary in hemodialysis patients, including those with marginal vessels. Upper arm fistulae are attractive due to the ease of creation and of achieving high access flow rates. Cephalic arch stenosis (CAS) can lead to failure of upper arm fistulae and is increasingly identified. We hypothesized that CAS is promoted by high blood flow rates, brachiocephalic fistulae, and an angle of cephalic vein insertion approaching 90 degrees.

All patients requiring a fistulogram between January 2004 and May 2006 had surveillance fluoroscopy of the central veins. Demographic, clinical and laboratory parameters were collected and the angle of the cephalic vein insertion measured by 3 blinded independent observers.

Fifty-eight patients had fistulograms and CAS was detected in 18 subjects. Significant differences between the CAS and non-CAS groups were brachiocephalic fistula site (p = 0.046), access flow (mL/min) (p = 0.012), and absence of diabetes (p = 0.03). Univariate predictors of CAS include access flow (per 100 mL/min) (p = 0.042), platelet count (p = 0.031) and calcium-phosphate product (p = 0.026). The relationship of brachiocephalic site and CAS was confounded by access flow [(per 100 mL/min)*brachiocephalic fistula site (p = 0.016)] and fistula age [brachiocephalic fistula site*fistula age (p = 0.017)]. In multivariate analysis, renovascular disease, calcium-phosphate product, platelet count and access flow (per 100 mL/min)*brachiocephalic fistula predicted CAS (p < 0.001, Negelkerke's R-Square = 0.55). The angle of insertion of the cephalic vein was not predictive for CAS.

CAS may be a long-term consequence of high blood flow rates. The interaction of access flow and brachiocephalic fistula supports the hypothesis that high flow through a brachiocephalic fistula promotes CAS. The multiple factors influencing cephalic arch remodeling require further research.