Highlights from the American College of Cardiology Annual Scientific Sessions 2003: March 28 to april 2, 2003

Study 

Published online June 10, 2003.Am Heart J 2003;146:19-26. Cost-effectiveness of sirolimus drug-eluting stents for the treatment of complex coronary stenoses: Results from the randomized SIRIUS trial

Presenter 

Dr David J. Cohen, Beth Israel Deaconess Medical Center and Harvard Clinical Research Institute, Boston, Mass

Background 

Clinical trials have demonstrated that sirolimus drug-eluting coronary artery stents (DES) dramatically reduce clinical and angiographic restenosis compared with conventional stents. Although current projections place the price of DES at approximately 2 to 3 times the price of a conventional stent, their use could result in cost savings if the need for repeat procedures is reduced. The aims of this study were 3-fold: 1) to compare the inhospital and long-term costs of percutaneous coronary intervention (PCI) using the DES with those of PCI using a conventional stent; 2) to examine the overall cost-effectiveness of the DES compared with conventional stenting in patients undergoing “real-world” PCI of coronary lesions; and 3) to examine the impact of clinical restenosis on the long-term costs of care for patients undergoing PCI in contemporary practice.

Medical resource utilization and costs were measured prospectively for 1100 patients randomized in the SIRIUS trial of sirolimus-eluting stents versus bare metal stents. The price of each sirolimus-eluting stent was estimated to be $3000 US. Index procedure costs, initial hospital costs, discharge-to-1-year costs, and total 1-year costs were compared. Acceptable US societal threshold costs per repeat revascularization avoided and per quality-adjusted life year (QALY) were estimated at <$10,000 and <$50,000, respectively. For the base case analysis, investigators assumed that patients in the conventional stent group would receive 1 month of antiplatelet therapy (clopidogrel) compared with 3 months in the DES group. Sensitivity analyses were conducted assuming 9 months of clopidogrel therapy for both groups.

Results 

Table I summarizes the costs for the DES compared with the conventional stent. The use of the DES resulted in a 62% reduction in restenosis compared with conventional stenting. Although the DES resulted in higher index procedure and initial hospital costs, total 1-year costs were not significantly different. This was due to cost savings with the DES during the discharge-to-1-year period. The cost-effectiveness ratio for DES compared with conventional stenting was ∼$1650 per repeat revascularization avoided or ∼$27,500 per QALY gained.

Table I. Summary of economic outcomes

		Sirolimus (n = 533)	Conventional (n = 525)	Δ	P
	Stents implanted	1.4	1.4	0	NS
	Costs ($)
	Index procedure	7252	4395	2856	<.001
	Initial hospital	11,345	8464	2880	<.001
	Discharge-to-1-year	5468	8040	2571	<.001
	Total 1-year	16,813	16,504	309	NS

NS, Not significant.

This study demonstrates that despite the higher up-front costs with the use of DES compared with conventional stents, the dramatic reduction in restenosis results in similar total 1-year costs and reasonable cost-effectiveness ratios.

Interpretation 

This eagerly-awaited analysis shows that DES is highly cost-effective in the population studied when compared with other accepted therapies, such as hemodialysis for end-stage renal disease ($50,000 per QALY gained) and tissue plasminogen activator for acute ST-elevation myocadial infarction ($32,678 per QALY gained). Further research is needed to determine if these results apply to patients with more complicated coronary artery disease such as saphenous-vein graft disease and multivessel disease.