Balloon angioplasty vs nitinol stent placement in the treatment of venous anastomotic stenoses of hemodialysis grafts after surgical thrombectomy

Abstract

Most arteriovenous hemodialysis grafts fail ≤18 months after implantation, most commonly due to intimal hyperplasia at the venous anastomosis. This open prospective study compared balloon angioplasty vs nitinol stent placement in the treatment of venous anastomotic stenosis after thrombectomy of prosthetic brachial-axillary accesses. Between February 2007 and December 2010, 61 patients with an initial thrombosis of a prosthetic brachial-axillary access were admitted to our hospital. Of these patients, 28 (46%), treated before June 2008, underwent thrombectomy plus balloon angioplasty of the venous anastomosis (group A), whereas the remaining 33 (54%) patients, who were treated after July 2008, underwent graft thrombectomy plus angioplasty with self-expanding nitinol stent placement (group B). Primary, primary-assisted, and secondary patency rates were calculated using Kaplan-Meier analysis and compared between the two groups with the log-rank test. Primary patency was 32% at 3 months, 24% at 6 months, and 14% at 12 months in group A, and the respective values were 85%, 63% and 49% in group B. Primary patency was significantly better in group B than in group A (P < .001; log-rank test). Cumulative median patency was 60 days in group A and 260 days in group B. Patient age, sex, comorbidities, graft material, and graft age did not have prognostic significance. Primary-assisted and secondary patency rates were significantly higher in group B. Graft thrombectomy plus angioplasty with self-expanding nitinol stent placement provides significantly higher patency rates compared with thrombectomy plus plain balloon angioplasty of the venous anastomosis.