The aim of this study was to compare neointima proliferation in three drug-eluting stents (DES) produced by the same company (Balton, Poland) which are covered with a biodegradable polymer and elute sirolimus (concentration: 1.0 and 1.2 µg/mm2), but have different stent platforms and strut thickness: stainless steel Prolim® (115 µm) and BiOSS LIM® (120 µm) and cobalt-chromium Alex® (70 µm). We analyzed data of patients with quantitative coronary angiography (QCA) and optical coherence tomography (OCT) at 12 months from BiOSS LIM Registry, Prolim Registry and Alex OCT clinical trial. There were 56 patients enrolled, in whom 29 Prolim® stents were deployed, in 11-BiOSS LIM® and in 16-Alex stents. The late lumen loss was the smallest in Prolim® subgroup (0.26 ± 0.17 mm) and did not differ from Alex® subgroup (0.28 ± 0.47 mm). This parameter was significantly bigger in BiOSS® subgroup (0.38 ± 0.19 mm; p < 0.05). In OCT analysis there was no statistically significant difference between Prolim® and Alex® subgroups in terms of mean neointima burden (24.6 ± 8.6 vs. 19.27 ± 8.11%) and neointima volume (28.16 ± 15.10 vs. 24.51 ± 17.64 mm3). In BiOSS® group mean neointima burden (30.9 ± 6.2%) and mean neointima volume (44.9 ± 4.9 mm3) were significantly larger. The morphological analysis revealed that in most cases in all groups the neointima was homogenous with plaque presence only around stent struts. In the QCA and OCT analysis regular DES (Prolim® and Alex®) obtained similar results, whereas more pronounced response from the vessel wall was found in the BiOSS® subgroup.
Keywords: Neointima proliferation; OCT; QCA; Stent strut cross-sectional area; Stent strut thickness.