ComparisOn of neointimal coVerage between zotaRolimus-eluting stent and everolimus-eluting stent using Optical Coherence Tomography (COVER OCT)

Background: Data on strut surface coverage of second-generation drug-eluting stents (DES) are limited. We investigated stent strut coverage of resolute zotarolimus-eluting stent (ZES-R) or everolimus-eluting stent (EES) at 9 months after implantation using optical coherence tomography (OCT). Methods: ComparisOn of neointimal coVerage betwEen zotaRolimus-eluting stent and everolimus-eluting stent using Optical Coherence Tomography (COVER OCT) is a prospective, randomized, multicenter trial comparing ZES-R to EES using OCT at 9 months after stent implantation. The primary end point was the rate of stent strut coverage at 9 months. Results: A total of 51 patients were randomized to receive either ZES-R (ZES-R group) or EES (EES group), and 47 stents (24 ZES-R and 23 EES) in 44 of 51 patients were evaluated by OCT both immediately after stent implantation and at 9 months. The neointimal thickness was not significantly different between the 2 groups at 9 months (ZES-R vs EES: 139 ± 58 vs 124 ± 42 μm, P =.31). The mean percentages of uncovered stent struts were 3.3% for ZES-R versus 3.4% for EES at 9 months (P =.51). The proportions of malapposed struts immediately after stent implantation (P =.89) and at 9-month follow-up (P =.34) were 0.8% and 0.7% for ZES-R versus 1.0% and 0.1% for EES, respectively. Thrombi were documented in 1 stent (1 [4.2%] in ZES-R vs 0 [0%] in EES). Conclusion: According to the sequential OCT evaluation, ZES-R and EES showed comparable neointimal thickness and the rate of uncovered stent strut at 9 months after stent implantation.