Pre-emptive or reactive treatment, angioplasty or stent-graft? The outcome for interventions for venous stenosis in early-cannulation arteriovenous grafts

Abstract

Background: Early-cannulation arteriovenous grafts (ecAVG) have good initial patency, but frequent episodes of reintervention for venous stenosis (VS) and thrombosis limit their use. Stent grafts (SG) have shown promise in reducing re-interventions and improving functional patency for dysfunctional ecAVG and recurrent VS. There is little data on the impact of stent grafts as the first elective procedure for VS. The aim of this study was to determine firstly, if treating VS whilst asymptomatic has a better outcome than treating after presentation with thrombosis; and secondly, to determine the best initial treatment for asymptomatic VS: SG or angioplasty. Methods: A retrospective study was performed of 259 ecAVG with a sutured anastomosis. The case-mix and outcomes of 153 who presented with VS was analysed by presentation (elective at surveillance or emergency following thrombosis), and then for only elective patients, by treatment (SG vs angioplasty). Results: There was no significant difference in case-mix and time to presentation by mode of presentation (100 elective and 53 with thrombosis) other than a higher rate of pro-thrombotic disorders in thrombosed ecAVG. Thrombosed ecAVG had poorer outcomes with increased re-intervention rates and thrombosis in the following year, and reduced long-term functional patency. In patients presenting electively, primary SG rather than angioplasty led to significantly reduced thrombosis rates, a longer time to re-intervention in the following year, and superior long-term functional patency. The use of SG was the same in both groups. Both the mode of presentation and the type of intervention performed were independently predictive of a poorer subsequent functional patency. Conclusions: Primary elective stent-grafting may be the optimal strategy to reducing maintenance costs with ecAVG.

Screening and surveillance of venous stenosis in AVG: Is it time to rethink our assumptions?

“…Recent observational series support the key impact of the initial treatment with a strong association between the type of initial treatment of VS and the subsequent outcome. 19 There have been two real advances in recent yearsstent grafts (SG) and drug-eluting balloons (DEB). Evolving data from both appear to offer benefits beyond that achieved with percutaneous balloon angioplasty (PBA).…”

“…18 The outcome of first intervention differs widely to that of secondary procedure. 19 There is largely observational evidence, supported by two RCT that the key time for identifying VS is before there is thrombosis, thrombosis itself being associated with poorer long-term outcomes. Given the large proportion of patients that had prior thrombosis in the RCT, any impact of screening/surveillance would be greatly diminished.…”

“…Recent observational series support the key impact of the initial treatment with a strong association between the type of initial treatment of VS and the subsequent outcome. 19…”

“…Evolving data from both appear to offer benefits beyond that achieved with percutaneous balloon angioplasty (PBA). 19,21 This would seem logical as the inherent pathological abnormality of VS (upregulated vascular smooth muscle cells) differs substantially from acellular atheroma in the arterial system, where angioplasty alone may be sufficient. The trials around SG are more advanced than DEB, and have the benefit of a more well recognised and defined role in symptomatic VS.…”

The impact of stent-graft sizing on venous stenosis re-intervention and arteriovenous graft patency: Free-floating stent outflow is associated with improved outcomes

“…Thus, effective intervention for VS is a key target for improving patient outcomes and reducing costs of vascular access provision. 1…”