Clinical and Economic Benefits of Stent Grafts in Dysfunctional and Thrombosed Hemodialysis Access Graft Circuits in the REVISE Randomized Trial
Is it more efficient and cost effective to maintain arteriovenous graft hemodialysis access circuits after rescue with percutaneous transluminal angioplasty with or without concurrent Viabahn stent grafts over 24 months?
Over 24 months, the use of stent grafts significantly reduced the number of reinterventions for all patients and reduced overall treatment costs for patients presenting with thrombosis.
Prospective Randomized Control Study
W. L. Gore & Associates Inc. (Flagstaff, Arizona).
Mohr, Belinda A. et al. Clinical and Economic Benefits of Stent Grafts in Dysfunctional and Thrombosed Hemodialysis Access Graft Circuits in the REVISE Randomized Trial. Journal of Vascular and Interventional Radiology , Volume 30 , Issue 2 , 203 - 211.e4
Arteriovenous grafts (AVGs) are an important option for patients on hemodialysis. Unfortunately, AVGs are susceptible to complications that can lead to reinterventions, increased costs and ultimately graft failure/abandonment. The conventional approach for failing grafts related to venous anastomotic stenoses has been percutaneous transluminal angioplasty (PTA). Recently stent grafts (SGs) have emerged as a promising supplemental approach to revising dysfunctional or thrombosed AVGs. In this study, inclusion criteria were patients with an AVG > 30 days old that was dysfunctional or thrombosed with a primary lesion having >50% stenosis and < 30 mm from the venous anastomosis. Patients were split into four groups with either dysfunctional/stenotic or thrombosed grafts and were treated with PTA alone or PTA with SG.
Overall, patients in the SG arm required significantly fewer total reinterventions compared to the patients in the PTA arm and the mean time to reintervention with SG vs PTA was 203 to 108 days. Specifically, patients with thrombosed AVGs treated with SG required 40% less reinterventions of any kind compared to those treated with PTA alone. Patients with graft dysfunction/stenosis initially treated with SG resulted in 16% less reinterventions compared to PTA, which was not statistically significant. Reintervention with PTA was reduced by 44% in patients presenting with thrombosed circuits who were treated with SG (statistically significant). Dysfunctional grafts had reduced PTA reintervention by 17% when the index procedure was augmented with SG (not statistically significant). Thrombosed grafts at presentation resulted in significantly more interventions overall, particularly more thrombectomy/thrombolysis procedures. SG placement in thrombosed grafts reduced future thrombectomy/thrombolysis by 36%.
When randomized by treatment, SG costs were 4% lower than initial PTA alone at 24 months although this was not statistically significant. However, when randomized by presentation, treatment of thrombosed grafts with SG reduced costs by 18% compared to PTA at 24 months. There was no significant cost difference between the two treatment groups with purely stenotic AVGs.
Stent graft placement significantly reduced total reinterventions over 24 months. Subgroup presentation show that reinterventions were significantly reduced at 24 months when thrombosed grafts were treated with stent grafts. Stent graft also decreased reinterventions in dysfunctional grafts, though not significantly. Cost was only statistically significantly reduced when stent grafts were used to treat thrombosed grafts.
Maintaining patent vascular access in ESRD patients is an obstacle that has proven to be fraught with difficulties and frustration for both patients and providers. These challenges inevitably translate into multiple vascular interventions and increased healthcare costs. The REVISE trial has demonstrated that AVGs treated with angioplasty and SG placement can reduce subsequent reinterventions and cost over 24 months, most significant in thrombosed circuits. Given that there are an estimated 457,957 ESRD patients on hemodialysis, consistently reducing reintervention would dramatically decrease the overall healthcare cost. The trial calculated that SG placement could reduce cost by $6,877 for each patient with a thrombosed AVG over two years. This would result in millions of dollars saved if even a small portion of the total ESRD population were treated with SG. Cost savings were contingent upon AVG survival to 2 years as initial upfront costs were expectedly higher with SG placement. This trial specifically looked at AVGs, and there is a larger prevalence of patients who receive dialysis via arteriovenous fistulas (AVFs). A similarly structured trial focused on AVFs and central stenoses could further evaluate initial intervention options and the subsequent effect on reinterventions and cost with AVFs. This could potentially lead to findings that would have larger cost savings to the system.
Bradley Unruh, MD PGY-3
Department of Radiology
Wake Forest Baptist Medical Center