OBJECTIVES: Sirolimus-eluting coronary stents (SES) are able to strikingly reduce instent restenoses as compared with conventional bare metal stents (BMS) and entered the European market in April 2002. We thus aimed at estimating SES expected economic impact on the national health-care system (NHS) in Italy. METHODS: A decision model was developed in Excel and four revascularization strategies were compared (PTCA, BMS, SES, CABG) in a population of patients with new stenoses in native coronary arteries. Four subgroups of lesions were studied, either single-vessel (small vessel, long lesion, Benestent-like lesion) or multivessel. Diabetics were separately analyzed. Incremental cost per revascularization avoided and cost per event-free year gained were calculated at a 1 and 5-year time frame and 3% discount rate was applied to both costs and efficacy. Input data were from the published trials: BARI, BENESTENT I&II, ARTS, RAVEL. A survey of 3298 patients in 3 cathlabs captured the real-life casemix and current practice and allowed to customize the model. Italian NHS charges were used to estimate the financial impact. RESULTS: In the first year after revascularization, as compared with BMS, SES averted 123-182 revascularizations in 1000 patients and gained 0.6-1.9 event-free months per patient; SES also saved €1036-€1800 per patient: a larger gain was achieved in those with multivessel disease and in the 5-year horizon, provided that the SES efficacy was constant over time. In diabetics the SES averted 15% more revascularizations and increased savings by 12%. In single vessel disease the breakeven point of SES efficacy was 72% and that of charge for stenting with SES was €7242 (17% higher than baseline). Overall forecasted savings to the NHS would be €38.927.652 per year, if SES replaced all the stents. CONCLUSIONS: SES is cost saving in a DRG-based reimbursement NHS, however, the uptake of SES can be supported through substantial update of charges while keeping a net economic gain.