Long-term clinical outcomes following drug-eluting and bare metal stenting in Massachusetts.

Background: Drug-eluting stents (DES) reduce the need for repeat revascularization, but their long term safety relative to bare metal stents (BMS) in general use remains uncertain. We sought to compare the clinical outcome of patients treated with DES vs. BMS. Methods and Results: All adults undergoing percutaneous coronary intervention (PCI) with stenting between April 1, 2003 and September 30, 2004 at non-US governmental hospitals in Massachusetts were identified from a mandatory state database. Patients were classified according to stent types used from the index admission. Clinical and procedural risk factors were collected prospectively. Risk-adjusted mortality, myocardial infarction, and revascularization rate differences (DES-BMS) were estimated through propensity score matching without replacement. 11556 patients were treated with DES and 6237 treated with BMS with unadjusted 2 year mortality of 7.0% and 12.6% respectively (p