Stent Graft versus Balloon Angioplasty for Failing Dialysis-Access Grafts

Abstract

with TEVAR was impressive. With longer follow-up, this may translate into improved survival with fewer long-term complications. Stent Graft versus Balloon Angioplasty for Failing Dialysis-Access GraftsHaskal ZJ, Trerotola S, Dolmatch B, et al. N Engl J Med 2010;362:494-503. Conclusion: Revision of a venous anastomotic stenosis of a prosthetic dialysis access graft with a stent graft provides longer-term patency and freedom from repeat intervention than revision with standard balloon angioplasty.Summary: Secondary patency of hemodialysis grafts is at best 50% at 3 years. Many interventions are typically required to maintain dialysis-access graft patency. The authors sought to test the hypothesis that revision of venous anastomotic stenosis with stent grafts constructed with the same material as the dialysis-access graft itself would improve long-term patency compared with that provided by revision with balloon angioplasty alone. Theoretically, stent graft revision would prevent elastic recoil associated with balloon angioplasty alone and prevent intimal hyperplasia in-growth at the venous anastomosis, resulting in improved patency of the revised grafts.This was a prospective multicenter trial. There were 190 patients undergoing hemodialysis with dialysis-access grafts and a venous anastomosis stenosis that were randomly assigned to receive balloon angioplasty alone or balloon angioplasty plus placement of a stent graft at the site of the venous anastomotic lesion. Patency of the treatment area and patency of the entire vascular access graft were the primary end points.At 6 months, patency of the treatment area was greater in the stent graft group than in the balloon angioplasty group (51% vs 23%, P Ͻ .001). Six-month patency of the dialysis access circuit was improved in the stent graft group vs the balloon angioplasty group (38% vs. 20%, P ϭ .008). Freedom from subsequent intervention at 6 months was also greater in the stent graft group than in the balloon angioplasty group (32% vs 16%, P ϭ .03). Restenosis was greater in the balloon angioplasty group than in the stent graft group (78% vs 28%, P Ͻ .001). Other adverse events at 6 months were equivalent in the two treatment groups.Comment: There is still a need for dialysis-access grafts. Results of this study suggest stent grafts provide better patency in treating venous anastomotic strictures of dialysis-access grafts than that provided by balloon angioplasty alone. Although the results are statistically significant, there are details to be considered before declaring the results clinically significant. Grafts in this study were treated before actual thrombosis. Many access grafts do not come to revision until they have thrombosed, and it is controversial whether surveillance and treatment of patent, but not thrombosed dialysis grafts, actually results in overall prolongation of usable access. In addition, 6 months after revision with a stent graft, there is primary patency in only half the patients. Stent grafts are more expensive than balloon angioplasty a...

Diagnosis and Treatment of Insufficient Dialysis Vascular Access

“…In the case of repeat stent occlusion, it is necessary to surgically place the graft again. A number of current studies describe improved patency rates compared to PTA alone for stenoses of the dialysis graft in the region of the venous anastomosis and the venous outflow when using covered stent grafts [79,80]. The study by Haskal et al is a prospective randomized multicenter study with only a six-month follow-up [80].…”

Novel Therapies for Hemodialysis Vascular Access Dysfunction

“…A previous 6-month trial comparison between stent grafts and PTA alone also reported better patency rates with the stent grafts (47). However, in the 6-month report, the graft thrombosis rates were not significantly different than the rates after PTA alone, and graft survival rates were not reported.…”

Effect of the time to intervention on the outcome of thrombosed dialysis access grafts managed percutaneously

“…P atent vascular access is critical for patients with kidney failure who rely on regularly scheduled hemodialysis. Detailed evidence-supported guidelines have been developed regarding vascular access placement (1)(2)(3)(4), and much has been written about the surveillance, maintenance, biology, cost, and interventional techniques for these accesses (5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15). Similarly, predictors of success following radiological intervention of these access sites have been evaluated, including pressure, the degree of stenosis, and procedure type (16,17).…”

“…Percutaneous endovascular techniques have proven to be successful with the added benefits of lower cost and periprocedural morbidity when compared to surgical thrombectomy (3,11). Studies have shown that surveillance of indwelling arteriovenous (AV) grafts can reduce the number of thromboses, and that procedure technique can influence success (11,12,(22)(23)(24). Allon et al (23) reported dramatic improvement in the maintenance of AV grafts in their dialysis population on implementation of a multidisciplinary approach that involved the transition of procedures to an outpatient setting, aggressive surveillance, and detailed logistical support.…”

“…Allon et al (23) reported dramatic improvement in the maintenance of AV grafts in their dialysis population on implementation of a multidisciplinary approach that involved the transition of procedures to an outpatient setting, aggressive surveillance, and detailed logistical support. The potential relationships of numerous variables to patency over time have been evaluated for graft access procedures (12,14,16,18,22,23) and several studies have addressed parameters for preventing thrombosis (5)(6)(7)15). However, to the best of our knowledge, no study has addressed the effect of the time interval/delay from clinical presentation of a thrombosis to the procedure on intervention success.…”