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Metallic stenting for treatment of central venous obstruction in hemodialysis patients.

BACKGROUND
Central venous obstruction is a serious and common complication in hemodialysis patients. The recurrence rate is high after balloon dilation, while surgical repair is hazardous in these chronically ill patients. The aim of this study was to evaluate the efficacy of primary Wallstent placement for treatment of hemodialysis-related central venous obstructions.


METHODS
Eighteen hemodialysis patients with symptomatic shunt dysfunction and arm swelling due to subclavian (n = 3) or innominate (n = 15) venous obstructions were treated at Kaohsiung Veterans General Hospital with primary Wallstent placement from November 1998 to August 2001. Technical success and complications were reported. Primary and secondary patency rates of stent and hemodialysis access were calculated by survival analysis with Kaplan-Meier method.


RESULTS
A total of twenty-five Wallstents were deployed for central venous stenosis (n = 18) and occlusion (n = 7) in these 18 hemodialysis patients. The initial technical success rate was 100%. Fourteen episodes of re-obstruction developed during the observation period. Of them, seven episodes occurred within the stent, four episodes outside of but abutting to the peripheral end of the stent, and another three episodes of re-obstruction were attributed to delayed shortening of the Wallstent. Six of the 14 episodes were treated percutaneously with angioplasty alone, while seven episodes necessitated additional stent placement. No stent migration or other complications were encountered. Primary patency rates of stent and hemodialysis access at 3, 6, 12 and 18 months were 100 and 89%, 73 and 68%, 49 and 42%, and 16 and 0%, respectively. Secondary patency rates of stent and hemodialysis access each were both 100% after 3 months, 93 and 100% after 6 months, 85 and 91% after 12 months and, 68 and 72% after 24 months.


CONCLUSIONS
Wallstents are safe to deploy, with excellent technical success for hemodialysis-related central venous obstructions. The Wallstent provides continued use of a hemodialysis access for a substantial period. However, repeated interventions may be necessary to maintain the patency.