STAG TRIAL – Is primary stenting better than angioplasty for iliac occlusions?


Primary stenting in iliac occlusion reduces rate of major periprocedural complications. Results of the STAG trial, a multicentre randomised clinical trial comparing angioplasty with stenting for the treatment of iliac occlusion were presented by Naomi Hersey, Sheffield Vascular Institute, Northern General Hospital, Sheffield, UK at the 2010 CIRSE congress in Valencia, Spain.

Hershey told delegates that both percutaneous transluminal angioplasty and primary stenting are key treatment options for iliac occlusions. The 1998 Dutch Iiliac stent trial, which was published in The Lancet, compared the primary stent to angioplasty with selective stent and found that while there was no significant difference in technical or clinical outcome, long-term follow-up showed that angioplasty with a selective stent was significantly different symptomatically. There was no published data comparing primary stent to angioplasty in iliac occlusion, she said. “In the six–centre prospective study, inclusion criteria were defined as more than three months of claudication, presence of an iliac occlusion of less than eight centimetres and at least a single vessel run-off”.

118 patients with iliac occlusion and symptoms of chronic leg ischaemia were randomised to either angioplasty (n=61) or angioplasty and stent insertion (n=57). If percutaneous transluminal angioplasty resulted in any antegrade flow, then a stent was not placed irrespective of the residual gradient. Periprocedural and 30 day complications were recorded. Long-term patency was assessed clinically using the Rutherford scale and angiographically by digital subtraction angiography at one and two years.

Four patients were excluded from the analysis due to protocol violations. There were increased complications within the angioplasty group versus the stent group (24 vs. 5.3%, p=0.004). There were increased complications within the angioplasty group (15 vs. 4%). There were no differences in clinical outcomes at two years. Immediately post procedure there was a significantly higher residual gradient within the angioplasty group group versus stent group (p=0.0001); at two years there was no significant difference in gradient (p=0.2).

Endovascular placement of stents has been proposed as a more effective treatment than angioplasty, a safe and simple treatment excluding additional costs associated with the use of stents.
The STAG trial is the only randomised controlled trial comparing angioplasty and stenting for the treatment of iliac occlusion. There was significantly increased primary failure rate for angioplasty versus stenting and also an increased rate of complication. At two years, the clinical and haemodynamic assessment were not significantly different.