Safety and efficacy of everolimus-eluting stent versus zotarolimus-eluting stent: A meta-analysis of randomized controlled clinical trials and observational studies

•Safety and efficacy of two drug-eluting stents ZES and EES were compared.•Both RCTs and observational studies were assessed collectively and separately.•In RCTs, EES and ZES showed comparable safety and efficacy.•In observational studies or pooled data, EES was safer and more efficacious.•The discrepancy between RCTs and observational studies were discussed.

BackgroundThe safety and efficacy of everolimus-eluting stent (EES) versus zotarolimus-eluting stent (ZES) are controversial both in randomized controlled clinical trials (RCTs) and observational studies. The aim of this study was to assess the safety and efficacy of EES versus ZES.MethodsPubmed, Embase, Cochrane database and www.clinicaltrials.gov updated to Mar 2014 with safety [major adverse cardiac events (MACE)], all-cause mortality, non-fatal myocardial infarction (MI), stent thrombosis (ST) and efficacy [target vessel revascularization (TVR), target lesion revascularization (TLR), target vessel failure (TVF), target lesion failure (TLF)] endpoints and follow-up of ≥ 12 months were identified.ResultsData from 11,778 patients in 8 RCTs and 34,850 patients in 26 observational studies were included. In RCT studies, no evidence indicating that EES was safer or more efficacious than ZES. In observational studies, EES associated with a significantly lower risk for MACE (RR: 0.56, 95% CI: 0.46-0.69), ST (RR: 0.59, 95% CI: 0.45-0.78), TVR (RR: 0.61, 95% CI: 0.47-0.79), TLR (RR: 0.57, 95% CI: 0.38-0.83) and TLF (RR: 0.69, 95% CI: 0.50-0.93). The pooled data of RCTs and observational studies showed that compared to ZES, EES associated with a significant lower risk for MACE (RR: 0.65, 95% CI: 0.54-0.78), ST (RR: 0.66, 95% CI: 0.52-0.83), TVR (RR: 0.72, 95% CI: 0.58-0.89), TLR (RR: 0.63, 95% CI: 0.49-0.82) and TLF (RR: 078, 95% CI: 0.62-1.00).ConclusionsIn RCTs, EES and ZES showed comparable safety and efficacy, while in observational studies or pooled data, EES was safer and more efficacious than ZES.