The effects of protrusion into the axillary vein on long-term outcomes of stent-grafts used to treat cephalic arch stenoses in dysfunctional brachiocephalic fistulas.

PURPOSE: To assess long-term patency rates of cephalic arch stent-grafts in brachiocephalic fistulas and the importance of device position.

MATERIALS AND METHODS: This retrospective study reviewed 152 patients with dysfunctional brachiocephalic fistulas and cephalic arch stenosis treated with Viabahn stent-grafts at a single tertiary center between 2012 and 2021. Median age was 67.5 years(25 - 91) and median follow up was 637 days(3- 3368). A grading system of protrusion was applied; Grade 0=no protrusion, Grade 1=perpendicular and Grade 2=in-line protrusion. Subsequent fistulograms were available in 133/152(88%)patients and were assessed for central vein stenosis within 10mm of the stent-graft. Clinical records were assessed for sequelae of stent-graft protrusion. Stent-graft primary and cumulative circuit patency were calculated using the Kaplan-Meier method.

RESULTS: One-hundred six(70%) stent-grafts protruded; 56 Grade 1 and 50 Grade 2. Central vein stenosis was seen in 1(2%) case of no protrusion(Grade 0) and 38(28%) cases of protrusion(p<0.0001). There was no significant difference in stenosis between Grade 1 and 2 protrusion(p=0.15). No adverse clinical sequelae occurred in 147(97%) patients. Eight patients had a new access subsequently formed in the same arm and 3/8 developed symptoms due to the previous stent-graft protrusion(all Grade 2). Primary patency of the stent-graft at 6 and 12 months was 73% and 50%. Cumulative access circuit patency at 1, 2 and 5 years was 84%,72% and 54%.

CONCLUSION: This study demonstrated that protrusion of a cephalic arch stent-graft into the central vein is safe, and only clinically relevant when a subsequent ipsilateral access is created.