Comparison of the major clinical outcomes for the use of endeavor^® and resolute integrity^® zotarolimus-eluting stents during a three-year follow-up

Background: Endeavor^®-zotarolimus-eluting stent (E-ZES) was the first ZES to be developed, and Resolute integrity^®-ZES (I-ZES) has been developed more recently. Comparative studies on long-term usage of these two ZESs have been rare. Objectives: The aim of this study was to compare the efficacy and safety of E-ZES and I-ZES during a long-term follow-up of patients who underwent percutaneous coronary intervention (PCI). Methods: A total of 767 patients who underwent PCI with E-ZES or I-ZES were eligible for this study. The primary endpoint was the occurrence of major adverse cardiac events (MACEs), defined as the composite of all-cause death, non-fatal myocardial infarction (MI), and any repeat revascularization. The secondary endpoint was stent thrombosis (ST). Results: After propensity score-matched (PSM) analysis, two PSM groups (193 pairs, n = 386, C-statistic = 0.824) were generated. During the 3-year follow-up period, the cumulative incidence of MACEs (hazard ratio [HR], 0.837; 95% confidence interval [CI], 0.464-1.508; p = 0.553) and ST (HR, 0.398; 95% CI, 0.077-2.052; p = 0.271) was similar for the E-ZES and I-ZES groups. Additionally, the cumulative incidences of all-cause death, cardiac death, non-fatal MI, and any repeat revascularization were not significantly different between the two groups. Conclusions: Although I-ZES utilizes a more advanced stent platform, stent design, and polymer system than E-ZES, both the ZESs showed comparable efficacy and safety during the 3-year follow-up period in this single-center, all-comers registry. However, further large-scaled, randomized, well-controlled trials with long-term follow-up are needed to verify these results.