Poly-l-lactide Polymer-Based Triple Drug-Eluting Stent with Abciximab, Alpha-Lipoic Acid and Sirolimus in Porcine Coronary Restenosis Model

This study evaluated the effect of a novel triple drug-eluting stent containing antithrombotic abciximab, antioxidative alpha-lipoic acid (ALA), and antiproliferative sirolimus in a porcine model. The coronary arteries of pigs were randomized into three groups: triple drug-eluting stent (TES; n=10), sirolimus-eluting stent (SES; n=10), and bare metal stent (BMS; n=10). At 28 days after stent implantation, a histopathologic analysis was performed. There were no significant differences in the injury score. There were significant differences in the neointimal area (2.3±0.6 mm2 in TES vs. 2.5±0.88 mm2 in SES vs. 3.3±0.58 mm2 in BMS, p<0.0001), percent area of stenosis (37.1±9.26% in TES vs. 46.1±15.9% in SES vs. 66.2±10.12% in BMS, p<0.0001), inflammation score (1.0 [range, 0.0-1.0] in TES vs. 1.5 [range, 1.0-2.0] in SES vs. 1.0 [range, 1.0-2.0] in BMS, p<0.05), and fibrin score (2.0 [range, 1.0-2.0] in TES vs. 2.0 [range, 1.0-2.5] in SES vs. 0.0 [range, 0.0-1.0] in BMS, p<0.0001) among the three groups. The occlusion rates using micro-computed tomography showed similar restenosis rates based on histologic analysis (35.4±8.39% in TES vs. 43.4±10.12% in SES vs. 71.4±4.38% in BMS, p<0.0001). TES demonstrated an inhibitory effect on the smooth muscle cells compared to the other stents. It also suppressed inflammation in the stented lesion compared to SES as evidenced by the inflammation score.