Very early neointimal coverage of new biodegradable polymer drug-eluting stent compared with durable polymer everolimus-eluting stent evaluated by optical frequency domain imaging.

Polymeric component is associated with the increased risk of delayed vessel healing and stent endothelialization. We aimed to clarify neointimal coverage within 1 month after implantation of the new-generation abluminal biodegradable polymer (BP) drug-eluting stent (DES) compared with the second-generation durable polymer (DP) everolimus-eluting stent (EES). Between November 2015 and October 2016, 32 BP-DES and 25 DP-EES were evaluated by optical frequency domain imaging (OFDI) within 1 month after the procedure. The average interval to follow-up OFDI was not significantly different between the groups (16.3 ± 7.7 days in BP-DES vs. 15.4 ± 7.4 days in DP-EES, P = 0.75). Neointimal coverage was significantly superior in BP-DES in both apposed and malapposed strut (apposed: 53.9% in BP-DES vs. 28.0% in DP-EES, P < 0.001; malapposed: 22.9% in BP-DES vs. 7.5% in DP-EES, P = 0.001). When the follow-up period was divided into < 2 and > 2 weeks, neointimal coverage was also significantly superior in BP-DES (< 2 weeks: 47.7% in BP-DES vs. 19.2% in DP-EES, P < 0.001; > 2 weeks: 60.1% in BP-DES vs. 37.4% in DP-EES, P = 0.001). The new-generation BP-DES showed excellent early neointimal coverage compared with the second-generation DP-EES in both apposed and malapposed struts.