Long-term coronary arterial response to biodegradable polymer biolimus-eluting stents in comparison with durable polymer sirolimus-eluting stents and bare-metal stents: five-year follow-up optical coherence tomography study.

OBJECTIVE The long-term coronary arterial response of biodegradable polymer biolimus-eluting stents (BES) remains unclear. We sought to evaluate the coronary arterial response of biodegradable polymer BES at 5 years after stent implantation using optical coherence tomography (OCT) as compared with that of durable polymer sirolimus-eluting stents (SES) and bare-metal stents (BMS). METHODS Five-year follow-up OCT was performed in 30 patients with 33 stents (10 with 12 BES; 10 with 11 SES; 10 with 10 BMS). Quantitative parameters and qualitative characteristics of the neointima were evaluated. A total of 5178 struts (BES, n = 2056; SES, n = 1410; BMS, n = 1712) were analyzed. RESULTS Uncovered struts were found in 15 out of 2055 struts in the BES (weighted estimate 0.01%, 95% confidence intervals [CI]: 0.00-0.33%) and 54 out of 1410 struts in the SES (0.11%, 95% CI: 0.00-3.33%) (odds ratio [OR] 0.12, 95% CI: 0.01-1.95, p = 0.13). None of 1712 struts were uncovered in the BMS. Cross-sectional qualitative analysis of neointimal tissue showed that the frequency of lipid-laden neointima tended to be lower in the BES (2.26%, 95% CI: 0.38-12.3%) compared with the SES (9.90%, 95% CI: 4.37-20.9%; OR 0.21, 95% CI 0.03-1.16, p = 0.07), and was similar to the BMS (2.23%, 95% CI: 0.54-8.74%; OR 0.98, 95% CI 0.13-7.14, p = 0.98). CONCLUSIONS Biodegradable polymer BES shows a favorable coronary arterial response compared with SES, but different response with BMS at 5 years follow-up. The observed frequency of in-stent neoatherosclerosis within BES was similar to BMS and tended to be lower than SES.