Angioscopic prevalence in diabetic patients with everolimus-eluting stent compared to paclitaxel-eluting stent, a serial observation of coronary angioscopy in multicenter

Background: Drug-eluting stents (DES) have reduced in-stent restenosis (ISR) and target legion revascularization (TLR). However, diabetes mellitus (DM) is still major predictor of ISR and TLR in the early phase after DES implantation. This study evaluated angioscopic characteristics in patients with DM having everolimus-eluting stent (EES) compared to those having paclitaxel-eluting stent (PES). Methods: Serial angiographic and angioscopic observation were performed in the first 12 months (average 8.8±3.2 months) in 195 stents of 176 patients who received EES (PROMUS-Element, n = 110) or PES (TAXUS-Element, n = 66) in our 2 hospitals. There were 48 diabetic patients who received EES and 30 diabetic patients who received EES. Then, the prevalence of angioscopic coverage of neointima, yellow grade, in-stent thrombus and TLR was compared between PES and EES, and between DM and non DM retrospectively. Results: The overall prevalence of TLR in our hospitals was 4.5% and TLR in patients with EES was significantly lower than that in patients with PES (3.6% vs. 6.3%, P = 0.032). TLR in DM patients was significant lower in patients with EES than those with PES (8.6% vs. 12.5%, P = 0.043). The overall average of neointima grade was 1.62 and neointima grade in patients with EES was lower than that in patients with PES (1.36 vs. 1.77, P = 0.031). And the prevalence of neointima grade in patients with DM was significantly higher in patients with PES than those with EES (2.28 vs. 1.31, P = 0.016). Prevalence of thrombus on the stent strut was significantly lower in patients with EES than those with PES (7.7% vs. 24.2%, P = 0.001). However, yellow grade was significantly higher in patients with EES than that in patients with PES (1.3 vs. 0.8, P = 0.043). Conclusion: These data suggested that EES showed greater neointimal suppression angioscopically than PES in diabetic patients and EES is more likely to reduce ISR and TLR in patients with DM than PES. It is thought that there is difference in pathological mechanism due to each dugs to suppress atherosclerosis, however it is insufficient. Moreover, in patients with EES there is more yellow neointima, and it is thought that regional inflammation continues and it might induce neoatherosclerosis. It is reported that the other limus-eluting stent such as sirolimus-eluting stent induces more yellow neointimal change. It need to investigate the association between polymer or drug and neointimal change.