Levosimendan is a novel intravenous drug that increases the calcium sensitivity of cardiac myofilaments, improves haemodynamic function and symptoms, and decreases relative mortality of patients with low-output heart failure. OBJECTIVE: To estimate the cost-effectiveness of treatment with levosimendan compared to dobutamine in patients with severe low-output heart failure. METHODS: The economic evaluation was based on a European clinical trial (LIDO), in which 203 patients with severe heart failure were randomised to 24h infusion with either levosimendan or dobutamine. Survival and resource utilisation data were collected for six months, and survival was extrapolated up to three years based on data from the CONSENSUS trial. Costs were based on drug usage and hospitalisation in the LIDO trial and the six-month follow-up. The price of levosimendan was arbitrarily set at € 668 (USD 600) per 5 ml vial, whereas the mean actual cost of dobutamine in the eight countries participating in the study was calculated (€ 13.70 per vial). The mean cost of a hospital day in the eight countries was used (basis 1998). RESULTS: The mean survival over six months was 157 (SD 51.5) days in the levosimendan group and 139 (SD 64.0) days in the dobutamine group (p < .01). When extrapolated up to three years, the gain in life expectancy was estimated at 0.35 years (discounted by 3%). Levosimendan increased the average cost per patient by € 1,154. The incremental cost per life year saved (LYS) was € 3,340. When accounting for a cost in added years of life, the incremental cost per LYS was higher, as expected. For example in Sweden, the cost per LYS increased from € 3,000 to € 20,800. CONCLUSIONS: The cost per LYS using levosimendan, both with and without accounting for costs in added years of life, compares favourably with other cost-effectiveness analyses in cardiology, e.g. USD 33,000/LYS for TPA treatment in the GUSTO trial.