Effectiveness and Safety of Drug-Eluting Stents in Ontario

Tu, Jack V.
Bowen, James
Chiu, Maria
Ko, Dennis T.
Austin, Peter C.
He, Yaohua
Hopkins, Robert
Tarride, Jean-Eric
Blackhouse, Gord
Lazzam, Charles
Cohen, Eric A.
Goeree, Ron.

From the Institute for Clinical Evaluative Sciences (J.V.T., M.C., D.T.K., P.C.A., Y.H.) and Sunnybrook Health Sciences Centre, University of Toronto (J.V.T., D.T.K., E.A.C.) - both in Toronto; McMaster University, St. Joseph's Healthcare, Hamilton, Ont. (J.B., R.H., J.-E.T., G.B., R.G.); and Trillium Health Sciences Centre, Mississauga, Ont. (C.L.) - all in Canada. Address reprint requests to Dr. Tu at the Institute for Clinical Evaluative Sciences, G106-2075 Bayview Ave., Toronto, ON M4N 3M5, Canada, or at [email protected].

New England Journal of Medicine 357(14):p 1393-1402, October 4, 2007. | DOI: 10.1056/NEJMoa071076

Background

The placement of drug-eluting stents decreases the frequency of repeat revascularization procedures in patients undergoing percutaneous coronary intervention (PCI) in randomized clinical trials. However, there is uncertainty about the effectiveness of drug-eluting stents, and increasing concern about their safety, in routine clinical practice.

Methods

From the Cardiac Care Network of Ontario's population-based clinical registry of all patients undergoing PCI in Ontario, Canada, we identified a well-balanced cohort of 3751 pairs of patients, matched on the basis of propensity score, who received either bare-metal stents alone or drug-eluting stents alone during an index PCI procedure between December 1, 2003, and March 31, 2005. The primary outcomes of the study were the rates of target-vessel revascularization, myocardial infarction, and death.

Results

The 2-year rate of target-vessel revascularization was significantly lower among patients who received drug-eluting stents than among those who received bare-metal stents (7.4% vs. 10.7%, P<0.001). Drug-eluting stents were associated with significant reductions in the rate of target-vessel revascularization among patients with two or three risk factors for restenosis (i.e., presence of diabetes, small vessels [<3 mm in diameter], and long lesions [greater/equal 20 mm]) but not among lower-risk patients. The 3-year mortality rate was significantly higher in the bare-metal-stent group than in the drug-eluting-stent group (7.8% vs. 5.5%, P<0.001), whereas the 2-year rate of myocardial infarction was similar in the two groups (5.2% and 5.7%, respectively; P=0.95).

Conclusions

Drug-eluting stents are effective in reducing the need for target-vessel revascularization in patients at highest risk for restenosis, without a significantly increased rate of death or myocardial infarction.

N Engl J Med 2007;357

1393-402.