Outcomes following coronary stenting in the era of bare-metal vs the era of drug-eluting stents

Context Although drug-eluting stents reduce restenosis rates relative to bare- metal stents, concerns have been raised that drug- eluting stents may also be associated with an increased risk of stent thrombosis. Our study focused on the effect of stent type on population- based interventional outcomes. Objective To compare outcomes of Medicare beneficiaries who underwent non-emergent coronary stenting before and after the availability of drug- eluting stents. Design, Setting, and Patients Observational study of 38 917 Medicare patients who underwent nonemergent coronary stenting from October 2002 through March 2003 when only bare- metal stents were available ( bare- metal stent era cohort) and 28 086 similar patients who underwent coronary stenting from September through December 2003, when 61.5% of patients received a drug- eluting stent and 38.5% received a bare- metal stent ( drug- eluting stent era cohort). Follow- up data were available through December 31, 2005. Main Outcome Measures Coronary revascularization ( percutaneous coronary intervention, coronary artery bypass surgery), ST- elevation myocardial infarction, survival through 2 years of follow- up. Results Relative to the bare- metal stent era, patients treated in the drug- eluting stent era had lower 2- year risks for repeat percutaneous coronary interventions ( 17.1% vs 20.0%, P <. 001) and coronary artery bypass surgery ( 2.7% vs 4.2%, P <. 01). The difference in need for repeat revascularization procedures between these 2 eras remained significant after risk adjustment ( hazard ratio, 0.82; 95% confidence interval, 0.79- 0.85). There was no difference in unadjusted mortality risks at 2 years ( 8.4% vs 8.4%, P=. 98), but a small decrease in ST- elevation myocardial infarction existed ( 2.4% vs 2.0%, P <. 001). The adjusted hazard of death or ST- elevation myocardial infarction at 2 years was similar ( hazard ratio, 0.96; 95% confidence interval, 0.92- 1.01). Conclusion The widespread adoption of drug- eluting stents into routine practice was associated with a decline in the need for repeat revascularization procedures and had similar 2- year risks for death or ST- elevation myocardial infarction to bare- metal stents.