Long-Term Outcomes Following Drug-Eluting Stents Versus Bare Metal Stents for Primary Percutaneous Coronary Intervention: A real-World Analysis of 11,181 Patients from the British Columbia Cardiac Registry

Background: Drug eluting stents (DES) are associated with reduced risk of restenosis when compared with bare metal stents (BMS). Their use in ST-elevation myocardial infarction (STEMI) is debated, owing to concerns about stent thrombosis. There are limited real-world data comparing DES versus BMS in STEMI. We conducted an observational analysis in this setting and rigorously adjusted for treatment selection bias. Methods: We analyzed 11,181 consecutive patients with acute STEMI who received either DES or BMS during 2008-2014 in the British Columbia Cardiac Registry. We analyzed target vessel revascularization (TVR) and mortality at 2 years. Results: Multivariable- adjusted, propensity-matched and inverse probability-treatment weighted analyses found DES to be associated with early and late survival up to 2 years but not TVR. However, when adjusting for measured and unmeasured confounders, instrumental variable (IV) analyses demonstrated that DES use was associated with reduced TVR up to 2 years (Delta = -6.7%, 95% CI: -10.0%, -3.4%, P < 0.001). DES use was not associated with mortality at 1 year (Delta = -2.3%, 95% CI: -5.0%, 0.4%, P = 0.100) but associated with reduced mortality at 2 years (Delta = -5.4%, 95% CI: -8.3%, -2.5%, P < 0.001). Stratified IV analyses indicated that this long-term survival benefit was largely attributable to the second generation DES. Conclusions: In this study of patients with STEMI, when adjusting for measured and unmeasured factors, DES use was associated with reduced TVR and long-term survival beyond 1 year. This long-term survival was largely attributable to the second generation DES. These real-world data are reassuring and support the use of DES for STEMI. (C) 2016 Wiley Periodicals, Inc.