Short Term Success of Treatments to Salvage Thrombosed or Failing Synthetic Arteriovenous Grafts in End Stage Renal Disease: A Systematic Review and Network Meta-Analysis of Randomised Controlled Trials

Abstract

This article used network meta-analysis to indirectly estimate differences between treatments to salvage thrombosed/failing synthetic arteriovenous grafts in end stage renal disease that have not been compared head to head. The synthesis of existing evidence showed that stent grafts perform better than balloon angioplasty in decreasing the failure risk at three months. The drug eluting balloon was ranked high as the best treatment, but the evidence stems from one small study and most comparative effect estimates were not statistically significant. Objective: There is currently uncertainty regarding the ideal treatment to salvage thrombosed or failing synthetic arteriovenous grafts (AVGs) in patients with end stage renal disease. Therefore, a systematic review up to December 2018 and network meta-analysis of randomised control trials (RCTs) that compared three month failure risk of available treatments was carried out. Methods: Medline, Scopus, Embase, and the Cochrane Library were the data sources. Pairwise meta-analyses were based on random effects models. Network meta-analysis was conducted within a frequentist framework with a multivariable random effects approach to model treatment effects across studies. The metric of choice was the odds ratio (OR) along with the associated 95% confidence interval (CI). Results: Sixteen two arm RCTs were included involving 2011 patients who were randomised to six different treatments (plain balloon angioplasty, open surgical repair, stents, stent grafts, drug eluting balloons (DEBs), and cutting balloons). The network of RCTs had a star like geometry with plain balloon angioplasty being the common comparator. There were no significant differences between treatments with regards to risk of failure at three months with the exception of stent graft use that significantly reduced the risk of failure compared with plain balloon angioplasty (OR 0.53, 95% CI 0.34e0.84). Based on surface under the cumulative ranking curve (SUCRA) values, the best interventions to salvage thrombosed or failing AVGs were DEB and stent grafts. Conclusions: Stent graft seems to perform better than plain balloon angioplasty in terms of saving thrombosed or failing AVGs. However, this network meta-analysis was limited by the lack of closed loops and thus unable to assess consistency between direct and indirect evidence. The efficacy of DEBs as a promising treatment deserves further investigation and new RCTs are required.