Stent Migration: A Risk in the Treatment of Renal Access Patients

Objectives: Central venous strictures often lead to significant arm swelling and access malformation in patients with chronic renal failure. The purpose of this study is to acknowledge the risk of stent migration in this subset of patients treated for failing access grafts. Methods: A retrospective chart review of patients undergoing diagnostic fistulagrams and percutanous intervention of malfunctioning accesses was done from June 2007 to November 2012 in two major hospitals in Baton Rouge, Louisiana. A total of 5184 fistulagrams were performed. 1189 (22.9%) procedures involved percutaneous thrombectomy of the accesses. 2882 (55.6%) procedures included balloon dilatation of the access or venous outflow strictures. 796 (15.3%) patients had stents placed either in the access or proximal central veins. Results: Of the 796 stents placed in this series, six migrated after deployment over varied time periods. Five stents migrated to the heart requiring open heart surgical removal. One patient had a stent migrate from the right subclavian vein to the innominate vein. Conclusions: Migration of stents can occur in the treatment of failing renal access grafts. This is the largest reported series to date in the literature of such events in renal failure patients. The majority of stents migrated to the heart. The high flow system generated by these renal access grafts and eventual gradual central vein dilatation in this patient population increase the risk of future migration. Interventionalists must be cognizant of this potential complication with the need for selective accurate placement of stents.Despite proper placement, stent migration may be unavoidable.