Temporal Changes in Coronary Revascularization Procedures, Outcomes, and Costs in the Bare-Metal Stent and Drug-Eluting Stent Eras

Abstract

Although drug-eluting stents have been shown to be cost-effective compared with bare-metal stents for select clinical trial patients, whether these findings apply to the general population is unknown. We used data from the Medicare 5% Standard Analytic Files to compare the practice and outcomes of coronary revascularization (by either percutaneous coronary intervention or coronary artery bypass grafting) in the United States between 2001 (pre-drug-eluting stent era, n=14 362) and 2004 (post-drug-eluting stent era, n=16 374). Between 2001 and 2004, the rate of revascularization increased from 837 to 931 per 100 000, whereas the proportion of patients who underwent percutaneous coronary intervention as an initial revascularization procedure increased from 67.5% to 75.2% (P<0.001). Over a median follow-up period of 25.5 months, no significant changes in mortality were found between 2001 and 2004 (13.8% versus 13.3%, P=0.193). Significant decreases were seen, however, in the incidence of repeat revascularization (17.1% versus 16.0%, P=0.012) and myocardial infarction (10.6% versus 8.5%, P<0.001). Over this same time period, total cardiovascular care costs per revascularized patient decreased by $1680 (95% confidence interval $1164 to $2196, P<0.001) whereas total noncardiovascular costs increased by $2481 per patient (95% confidence interval $1844 to $3118, P<0.001). When the impact of overall procedural volumes was considered, aggregate cost to the Medicare program for cardiovascular services increased by $544 million over the 2-year follow-up period. Risk-adjusted results for both the clinical and economic outcomes showed similar trends. Among the Medicare population undergoing coronary revascularization, the introduction of drug-eluting stents was associated with increased use of initial percutaneous coronary intervention and reduced bypass surgery along with improved clinical outcomes over approximately 2 years of follow-up. Although total cardiovascular-related costs per revascularized patient decreased over this time period, total cost to the Medicare system still increased owing to greater overall use of revascularization procedures.