Open Thrombectomy of Arteriovenous Fistulas: Worth the Effort or Is It Time to Move On?

Abstract

Arteriovenous (AV) fistulas are the preferred hemodialysis access for patients with end-stage renal disease, although multiple percutaneous interventions are typically needed to maintain functional patency. When AV fistulas thrombose, however, there is debate whether open thrombectomy procedures should be attempted to salvage the access. This study was designed to evaluate outcomes after open thrombectomy of AV fistulas compared with polytetrafluoroethylene (PTFE) AV grafts. We identified all patients who underwent an open thrombectomy procedure for a thrombosed AV fistula or PTFE graft at a single academic medical center between January 2006 and March 2017. The specific type of AV fistula or graft was evaluated as well as patient demographics, comorbidities, medications, and interventions performed to maintain fistula patency. The primary outcome measures—successful dialysis after thrombectomy and time to recurrent thrombosis—were analyzed using Kaplan-Meier and Cox regression models. During the study period, 221 thrombectomy procedures were performed in 160 patients (mean age 52 years, 60% female), of which 82 (37%) were undertaken in AV fistulas and 139 (63%) in AV grafts. Patients with AV fistulas (24% radiocephalic, 42% brachiocephalic, and 34% brachiobasilic), were less likely to be diabetic or have ischemic heart disease (both P < .05) as patients with AV grafts but just as likely to be on antiplatelet or statin agents. After thrombectomy, there was no difference in use of adjuvant interventions to maintain patency (67% fistula vs 73% graft; P = .4), and an equal number of patients in both groups dialyzed successfully (62% fistula vs 55% graft; P = .3) at least once. However, rates of recurrent thrombosis at 1 year were significantly lower for AV fistulas vs grafts (P < .05; Fig), which was confirmed in multivariate analysis where AV fistulas had a 37% lower risk of failure (hazard ratio, 0.63; 95% confidence interval, 0.43-0.93; P < .05) after controlling for confounders. Our data suggest that AV fistula thrombectomy is successful in nearly two-thirds of cases, with improved long-term outcomes compared with PTFE grafts. While the risk of access failure is high after thrombectomy, efforts to salvage AV fistulas are effective in most patients and should be undertaken when feasible.