The SSTARS (STeroids and stents Against Re-Stenosis) Trial: Different stent alloys and the use of peri-procedural oral corticosteroids to prevent in-segment restenosis.

Abstract

Stent design and technological modifications to allow for anti-proliferative drug elution influence restenosis rates following percutaneous coronary intervention (PCI).
The main aim of this study was to investigate whether peri-procedural administration of corticosteroids or the use of thinner strut cobalt alloy stents would reduce rates of binary angiographic restenosis (BAR) after PCI. In addition, the role of the acute phase highly sensitive C-Reactive protein (hs-CRP) in restenosis in bare metal stents (BMS) was also investigated. This was a two centre, mixed single and double blinded, randomised controlled trial using a factorial design.
The use of prednisolone was compared against placebo, starting at least six hours pre-PCI and continued for 28 days post-PCI. Additionally, cobalt chromium (CoCr) stents were compared to stainless steel (SS) alloy stents, in patients admitted for PCI. The primary end-point was BAR at six months.
Three hundred and fifteen (359 lesions) were randomly assigned to either placebo (n=145) or prednisolone (n=170) and SS (n=160) or CoCr (n=160). The majority (58%) presented with an acute coronary syndrome (ACS), 11% had diabetes and 287 (91%) completed angiographic follow up. The primary endpoint, binary angiographic restenosis, occurred in 26 cases in the placebo group (19.7%) versus 31 cases in the prednisolone group (20.0%) respectively, p=1.00. For the comparison between SS and CoCr stents, BAR occurred in 32 patients (21.6%) versus 25 patients (18.0%) respectively, p=0.46.
Hs-CRP was monitored at 5 points during the trial. The pre-PCI hs-CRP measurement was ≤5mg/l in 213 patients (71%) of whom only 28 (13%) had a raised CRP at day 7. There was some evidence of prednisolone suppressing hs-CRP response at day 7 (-5.98 mg/L, 95%CI: -8.35 to -3.61, p<0.001). There was no correlation between lowering hs-CRP and stenosis diameter at follow-up.
This study showed that treating patients with a moderately high dose of prednisolone to cover most of the period of inflammation associated with restenosis in BMS did not reduce the incidence of BAR. There was also no significant reduction in six month BMS restenosis rates with stents composed of CoCr alloy compared to SS alloy and no observed relationship to hs-CRP.