Two-year Clinical Outcomes Following Everolimus-eluting Stent Use for Off-label Versus On-label Indications: From the Korean Multicenter Drug-eluting Stent Registry

Abstract

Background: Everolimus-eluting stent (EES) implantations have a relatively low rate of major adverse cardiac event (MACE) and target lesion revascularization (TLR) in patients with off-label use. However, the clinical outcome in the Korean population regarding EES in patients with off-label use is not well known. Objects: The aim of the current analysis was to compare the clinical outcomes of on-label and off-label EES use over a 2-year follow-up period. Methods: Using patient-level data from a stentspecific, prospective, all-comer registry, we evaluated 987 patients (1,342 lesions) who received an EES (XIENCE VⓇ, Abbott Vascular, Santa Clara, CA, USA) implantation between February 2009 and April 2011. The primary outcome was assessed: 2-year MACE (a composite endpoint of death from any cause, spontaneous myocardial infarction (MI), and any repeat revascularization). The clinical outcomes in the on- and off-label groups were compared at 2 years. Results: The majority of patients (79.0%) were treated for ≥1 off-label indication. The median duration of the clinical follow-up in the overall population was 2.0 years (interquartile range 1.9–2.1). At 2-years after the EES implantation in the enrolled patients, MACE occurred in 71 (7.9%) patients, cardiac death in 12 (1.3%), MI in 4 (0.5%), target vessel revascularization (TVR) in 33 (3.8%), TLR in 22 (2.5%), and definite or probable stent thrombosis (ST) in 1 (0.1%). Offlabel EES implantations tend to increase the risk of 2-year MACE (4.7% vs. 8.8%, p = 0.063) without statistical significance. However, the rates of TLR were higher in the off-label EES implantations (0.0% vs. 3.2%, p = 0.013). In the multivariable analysis, renal failure, previous bypass surgery, previous cerebrovascular accident, and left main lesions were associated with 2-year MACE in patients with EES implantations. Conclusions: The incidence of 2-year MACE was 7.9%, which that might be acceptable in all-comer patients treated with EES implantations. Although the off-label use of EES was not statistically associated with an increased risk of MACE, the TLR rate was higher in the off-label group, suggesting that physicians need to pay attention to high risk patients with the use of EES implantations.