Prevalence and clinical significance of anatomic variant in cephalic arch on preoperative mapping venography

The aim of the current study was to determine the prevalence of anatomic variant in cephalic arch on preoperative mapping venography and evaluate patency rates and predictors of patency in patients with brachiocephalic fistulas. The prevalence of anatomic variant in cephalic arch was retrospectively evaluated in 1004 consecutive patients who underwent bilateral preoperative mapping venography from July 2006 to December 2018 in a single center. The overall prevalence of anatomic variant in cephalic arch was 17.2% (173/1004). For patency analysis, 128 patients with brachiocephalic fistulas were divided into two groups: a standard anatomy (SA) group (n = 97) and a variant anatomy (VA) group (n = 31). There were no significant differences in clinical characteristics between the two groups. The primary patency rate did not differ significantly between the two groups. The secondary patency rate was significantly (p = 0.009) lower in the VA group than in the SA group. Older age (HR 1.03; 95% CI 1.01-1.05; p = 0.007) was a negative predictor of primary patency, and antiplatelet agent (HR 0.53; 95% CI 0.33-0.84; p = 0.007) and large-diameter cephalic vein (HR 0.52; 95% CI 0.31-0.86; p = 0.012) were positive predictors of primary patency. Older age (HR 1.04; 95% CI 1.01-1.07; p = 0.011) and anatomic variant in cephalic arch (HR 2.9; 95% CI 1.19-7.06; p = 0.019) were negative predictors of secondary patency. The current study provides insight into the clinical significance of anatomic variant in cephalic arch. Anatomic variant in cephalic arch should be considered as a potential risk factor for decreased patency of brachiocephalic fistula during preoperative planning.